Oligocene paleogeography of southern New Zealand: sedimentological/paleontological evidence for forested land, estuaries, rocky and sandy shores
Daphne E Lee, Department of Geology, University of Otago, PO Box 56, Dunedin, New Zealand
Jon K Lindqvist, Department of Geology, University of Otago, PO Box 56, Dunedin, New Zealand
Alan G Beu, GNS Science, PO Box 30 368, Lower Hutt, New Zealand
Dallas C Mildenhall, GNS Science, PO Box 30 368, Lower Hutt, New Zealand
Elizabeth M Kennedy, GNS Science, PO Box 30 368, Lower Hutt, New Zealand
Nick Mortimer, GNS Science, Private Bag 1930, Dunedin, New Zealand
P Jane Forsyth, GNS Science, Private Bag 1930, Dunedin, New Zealand
We provide evidence that indicates substantial forested islands existed in southern New Zealand during maximum marine transgression in the mid-late Oligocene. One large island (~140 km x 100 km) on Otago Schist basement had shorelines near Kokonga, Naseby, Queenstown on the margin of the subsiding Waiau Basin, and near Waikaia and Waikaka. A meandering river system drained south into the Pomahaka Embayment. The Pomahaka coastline was likely contiguous with the Catlins Block, a substantial 80 x 70 km region of uplifted Murihiku Terrane basement that probably extended south to Stewart Island. The western coastline of the Catlins Block formed a gently indented ridge and valley system that was onlapped during periods of higher sea level. Elsewhere on the East Southland platform, at Cosy Dell, a forested island with a river and estuary formed another rocky shore directly on Murihiku basement. Further south and west, the sea lapped on exposed basement rocks of Brook Street Terrane at Bluff and around the Longwood Range near Pourakino. On the west side of the Waiau graben, Oligocene rocky shorelines such as that at Mt Luxmore formed on the Fiordland margin. Collectively, these islands in southern New Zealand covered an area of at least 20,000 km2, about the same size as present day New Caledonia. Oligocene sea level was relatively stable, fluctuating about +30 m, allowing periodic connection of the basement terrane islands separated by shallow drowned valleys. These substantial subtropical islands provided a wide variety of habitats able to support a diverse biota.
24,000 cal. years of vegetation and climatic changes in a south-central chilean maar (39°S).
Ana M. Abarzúa, Instituto de Ciencias Ambientales y Evolutivas. Universidad Austral de Chile, Chile.
Marcelo Arévalo, Department of Geology, FBVI, University of Trier, Germany.
Helge W. Arz, Department of Marine Geology. Leibniz Institute for Baltic Sea Research Warnemünde (IOW), Germany.
Rolf Kilian, Department of Geology, FBVI, University of Trier, Germany.
Antonio Maldonado, Centro de Estudios Avanzado en Zonas Áridas, Universidad de La Serena, Chile.
Laguna Espejo and Laguna Reloj (39ºS/72º10´W; 320 m asl) have been described as maar-like monogenetic volcanic lakes both ~550 m in diameter and 35 m of water depth. Due to the low ratio between diameter and water depth, these maar-lakes provide ideal conditions for undisturbed and often anoxic sediment deposition and prservation. The lakes are situated at the west-side of the Last Glacial Maximun (LGM) moraine belt so they were not affected by the glacial advances, becoming an ideal long-lived and climate-sensitive lakes in south-central Chile. The 39ºS also represent a key position to test variations of the northern margin of the Southern Westerly Winds (SWW) during the last glacial-interglacial cycle.
Seismic profiles show several reflectors and a sediment thickness of more than 15 m depth in both lakes. Five gravity cores and two long piston cores have been retrieved from Laguna Espejo. Sedimentological (MS and LOI), geochemical (XRF-scanner), tephroestratigraphical, and palynological results reach back up to 24,200 cal yr BP, based on 10 AMS 14C dates. Laguna Espejo is the oldest terrestrial multi-proxy, high-resolution record at this latitude and its paleoclimatic contribution can be linked with the dynamics of the SWW and their multi-millennial variability along the Southern Hemisphere. Cold and very humid conditions prevailed during the LGM (24-19 ky BP), warmer and drier conditions characterized the early Holocene (11-6 ky BP), and more variable conditions were recorded during the late Holocene (last 6 ky BP).
A 40ky year record of frontal shifts linked to the westerly wind belt offshore southern Australia: implications for broad inter-oceanic connections
Patrick De Deckker, Australian National University
Matthias Moros, Baltic Sea Research Institute
Kerstin Perner, Baltic Sea Research Institute
Claudia Moros, Baltic Sea Research Institute
Eystein Jansen, University of Bergen
A high-resolution record of a deep-sea core from offshore Kangaroo Island has provided crucial information on the behaviour of oceanic currents such as the Leeuwin Current [LC] that originates in the Indo-Pacific Warm Pool and the central Indian Ocean gyre. The behaviour of the LC above the core site is directly linked to the westerly wind belt which, when close to southern Australia and the southern tip of South Africa, prevents the transport of warm tropical waters along southern Australia, and in parallel, the Aguhlas Leakage[AL] into the Atlantic Ocean is stopped. When the westerly wind belt is located further south in the Southern Hemisphere, the behaviour of the LC and AL are changed.
The use of the oxygen isotopic composition of 2 different species of planktic foraminifer found in the same samples in the core mentioned above also inform on water column stratification and, therefore, can imply the presence or absence of the westerly wind belt over the core site.
The chronology of the core is based on a high-resolution stable isotopic data and numerous 14C dates. In addition, we also have a high-resolution record of SST reconstructed from alkenones and the Mg/Ca of 3 species of planktic foraminifers.
For preliminary information, refer to De Deckker, P. , Moros, M., Perner, K. & Jansnen, E. (2012). Influence of the tropics and southern westerlies on glacial interhemispheric asymmetry. Nature Geoscience 5, 266-269.
A collective approach to identifying opportunities and solutions for improving wilding conifer management in New Zealand
Victoria Froude, Pacific Eco-Logic Ltd
Sherman Smith, Ministry of Primary Industries, New Zealand
A comprehensive report on the status of wilding conifers and their management was prepared in 2011. This and an accompanying report made a series of recommendations agreed to by the multi-stakeholder Wilding Conifer Management Group, which was involved throughout the report preparation processes. A key recommendation was that a non-statutory national wilding conifer management strategy be developed. The strategy development will be led by the Ministry for Primary Industries (in line with its biosecurity system leadership role) and will be a collective process actively involving stakeholders through a stakeholder forum
The status report identified a range of issues for the strategy to address. This presentation will discuss some of these issues and how the wilding conifer strategy could assist with their resolution:
• The ongoing and increasing range of spread from old or legacy plantings by public agencies and the private sector;
• Unintended consequences of different public policies on wilding conifer management (including potential changes in planting patterns);
• Inaccurate perceptions leading to inappropriately timed or inadequate actions.
• Constrained funding and using more consistent monitoring and reporting to make a better case for funding;
A funny thing happened on the way to the glacial: lake records of climate variability in Australia before and after the last glacial.
Jessica Reeves, University of Ballarat
OZ-INTIMATE members, various
Palaeoclimate time-slice reconstructions have generally focussed on the “big” events e.g. Last Glacial Maximum (21 ka) and mid-Holocene optimum (nominally 6 ka). Recent syntheses by the OZ-INTIMATE working group have identified some other, perhaps more intriguing climate events such as the early glacial, (~26-24 ka) and the deglacial (14-12 ka), both of which resonate with changes in the Antarctic and New Zealand palaeoclimate records. In Australia, these periods show increased variability in both temperature and effective precipitation and differing responses in the north and south of the continent.
We focus here on well-constrained lacustrine records from these periods to investigate the variability both within site and between regions, looking to extrapolate local influences from more broad-scale climatic drivers. We include here records from a transect along eastern Australia from Lake Carpentaria in the north to Lake Keilambete in the south. Multiple proxies are utilised including pollen, charcoal, dust, ostracods and carbonate geochemistry.
A high-resolution chronology of the Initial Burning Period following Polynesian arrival in New Zealand
David McWethy, Montana State University, USA
Janet Wilmshurst, Landcare Research, Lincoln, New Zealand
Matt McGlone, Landcare Research, Lincoln, New Zealand
Cathy Whitlock, Montana State University, USA
The arrival of humans in New Zealand 700-800 years ago was accompanied by widespread forest transitions linked to human-set fires. Palaeoecological data from wetland and lake-sediment cores suggest an Initial Burning Period (IBP) was responsible for conversion of forests to open grasslands and shrublands but estimates of the duration of this period vary from decades to centuries. We used a suite of 20 radiocarbon dated macrofossils from two South Island lakes near the western extent of forest clearance to better constrain the duration of the period of burning that transformed forests to open vegetation. Radiocarbon dates were obtained from consecutive layers of lake sediment spanning the IBP and were then used to develop high-resolution chronologies for the IBP. Deposition models using Oxcal software suggest the duration of the IBP that led to dynamic ecological change was as brief as several decades, and pollen analyses indicate vegetation response coincided with increased fires and was equally rapid. Our results further support the idea that rapid conversion of forests to open vegetation was a consequence of feedbacks that fundamentally altered landscape flammability in New Zealand forests. The arrival of humans in New Zealand offers a striking example of the rate at which small populations can alter fire regimes and vegetation structure through fire-vegetation feedbacks and illustrates how fuel-rich environments may quickly transition to new stable states.
A high-resolution record of fire and vegetation change from Bega Swamp, southeastern Australia.
Simon Haberle, Australian National University
Chris Turney, University of New South Wales
Nick Porch, Deakin University
Geoffrey Hope, Australian National University
Perceptions of fires in the Australian environment are often dominated by notions of their destructive powers that lead to deforestation and degradation of diverse and “pristine” habitats. These notions have been exacerbated over the last two decades by mega-fire events associated with a series of prolonged drought events in which vast areas of forest were lost and associated stored carbon was released into the atmosphere. While these events have clearly demonstrated the potential significance of forest fires for contributing to future climate change little is known about the long-term history of the interaction between fires, vegetation and climate change in our region. Records of ancient macroscopic charcoal show that fires have been an important factor in forest dynamics. Recent developments in statistical methods applied to microscopic charcoal analysis have greatly improved our capacity to reconstruct past fire frequencies (Higuera et al. 2009). Here we apply these techniques to a new high-resolution pollen and charcoal record from Bega Swamp to look at whether or not fire regimes have changed significantly over the last 15000 years and, if so, what are the drivers and consequences of these changes.
Higuera, P.E., et al. (2009) Vegetation mediated the impacts of postglacial climatic change on fire regimes in the south-central Brooks Range, Alaska. Ecological Monographs 79:201-219.
A new high-resolution record of South Island hydrology from Lake Ohau sediments, South Island, New Zealand
Richard Levy, GNS Science
Marcus Vandergoes, GNS Science
Gavin Dunbar, Victoria University of Wellington
Heidi Roop, Victoria University of Wellington
Phaedra Upton, GNS Science
Paul Stumpner, University of California-Davis
Bob Ditchburn, GNS Science
Gary Wilson, Otago University
Chris Moy, Otago University
Jamie Howarth, Otago University
Sean Fitzsimons, Otago University
Lake Ohau (44°10'S, 169°49'E) contains a ~100+ metre-thick laminated sedimentary sequence that likely spans the past 17,000 years and offers potential to examine hydrologic response to changes in the South Westerly Winds. Preliminary work on sediment trap samples and modern environmental data demonstrates that Lake Ohau sediments reflect seasonal variations in South Island hydrology. Annual changes in lake sedimentation include a dark coloured, mud-rich, biosilica-poor “winter layer” and thicker silt-rich spring-summer layers containing a diatom bloom event. This sequence records seasonal response to changes in lake inflow, which is typically lowest in winter and peaks during spring/summer. Maximum lake turbidity and associated peak silt-load also occurs during spring and coincides with high diatom productivity.
Short sediment cores (<6 m) from Lake Ohau exhibit downcore variation in colour intensity that highlight coherent mm- to cm-scale sedimentary couplets. A detailed chronology for the upper 0.6 m has been established by combining a well-defined 137Cs and 210Pb profile with a horizon recording a 1994-95 flood event. The resulting age model allows us to correlate sedimentary couplets with lake hydrological data, and shows that layers exhibit strong correspondence with lake flow. Preliminary spectral analysis of downcore colour intensity exhibits statistically significant variance centred at seven and eleven years, suggesting that Ohau records variability in South Island precipitation at ENSO-scale frequencies. These preliminary data indicate that recovery of a complete sedimentary sequence from Lake Ohau could provide an unprecedented opportunity to reconstruct South Island hydrology from the LGM to present at decadal to annual timescales.
A new pollen record from northwest Nelson, New Zealand.
Ignacio A. Jara, Victoria University of Wellington
Rewi Newnham, Victoria University of Wellington
Marcus Vandergoes, GNS Science
David Lowe, University of Waikato
Courtney Foster, University of Waikato
Patricio Moreno, Universidad de Chile
Brent Alloway, Victoria University of Wellington
Comparing paleo-environmental records from equivalent ecosystems across the Southern Hemisphere can provide wider insights in the fields of biogeography, paleoclimate and human-environment interactions. This is especially true for the few continental landmasses that extend south of 40°S and share important geographic and biotic properties, and yet hemispheric-scale perspectives are uncommon. Here we present a first attempt to compare postglacial climate changes determined from pollen-vegetation records between New Zealand and Southern Chile (~40°S). As a principal example from New Zealand, we present a new radiocarbon-dated pollen record from Adelaide Tarn, a small lake located in north-western Nelson, New Zealand (41°S).
The pollen record from Adelaide Tarn reveals a continuous vegetation history covering the last 14,000 years. We distinguish three main phases: (1) high abundance of Nothofagus fuscas-type (Fuscospora) and the herb families Asteraceae, and Poaceae between 14,000-13,000 cal yr BP; (2) low abundance of Fuscospora and successive increments of Podocarp trees between 13,000-6,000 cal yr BP; and (3) high abundance of Fuscospora and the aquatic Isoetes between 6,000 to the present.
These results support previous suggestions that north-western Nelson area could have been a late-glacial refugium for Nothofagus spp. A local early-Holocene thermal maximum appears to be reached between ~11,000-9,000 cal yr BP, followed by a progressive deterioration of climate suited to warm-termperate rainforest. Similar patterns are seen in southern Chile (40°S), suggesting a broad zonal synchronism in paleoclimate trends across the Southern Pacific. If so, this hemispheric-scale comparison can highlight the environmental and human-history differences between these two regions
A new view of hybridisation and speciation in the New Zealand Fuscospora beech species
Rob Smissen, Manaaki Whenua - Landcare Research
Peter B Heenan, Manaaki Whenua - Landcare Research
Sarah J Richardson, Manaaki Whenua - Landcare Research
The New Zealand species of Nothofagus subgenus Fuscospora are a closely related and inter-fertile group with overlapping distributions that have long been recognised to hybridise in nature. Although hybrid fertility has been demonstrated for some combinations, hybrids can be cryptic. In the absence of hard evidence, speculation about the extent of geneflow among the species has proliferated, along with a view that the taxa are arbitrary divisions of a coenospecies. The development of microsatellite markers for these trees has allowed, for the first time, rigorous tests of the frequency of hybridisation and the extent of gene-flow among the species and an independent test of taxonomic boundaries based on morphological characters. We find that reproductive isolation among the species is stronger than has been hypothesised and suggest that speciation has occurred via divergent natural selection in different environments (ecological speciation). The two varieties of N. solandri (N. solandri var. solandri and N. solandri var. cliffortioides) may represent this process in action. Alternative historical explanations of disjunctions in the distribution of beech species in New Zealand can now be tested where they imply different genetic consequences.
A preliminary investigation combining modern DNA and ancient DNA of the threatened Araucaria araucana (Pehuén) tree in central Argentina and Chile.
Kate Johnson, Queen's University Belfast
Araucaria araucana (the Pehuén or Monkey Puzzle tree) is a protected species in southern South America. The modern day distribution lies across central Argentina and Chile (ca. 37 - 42° S) but is fragmented, with isolated patches occurring up to 70 km from other A. araucana forests. Despite its significant cultural and economic significance, the species is currently under threat from human pressures, such as clearance, overgrazing and the introduction of exotic conifers.
A phylogenetic analysis of the modern day distribution was conducted on around 150 samples of fresh and herbarium needles, using multiple genetic markers. A palaeoecological study was carried out on a short sediment core from Laguna Villa Pehuenia, Neuquén, Argentina to establish the environmental history of the region. The results of this highlight that A. araucana has been present in the region throughout the last 3,000 years. Ancient DNA (aDNA) analysis of A. araucana pollen from this core will be extracted and analysed to investigate the potential of extracting aDNA from this species. The A. araucana species is an ideal species to use due to its low pollen dispersal distance and relatively large (~80 μm) pollen grains.
Combining palaeoecological data with modern genetics and aDNA provides the potential for a richer source of palaeoenvironmental data. Combining multi-proxy analysis of the spatial history of a species with modern genetics and temporal history from aDNA provides a richer understanding of the changes in species distribution through time.
A single dispersal out of Australia followed by remarkable global colonization by the bee genus Hylaeus (Colletidae)
Mark Stevens, South Australian Museum
Pelin Kayaalp, Flinders University of South Australia
Michael Schwarz, Flinders University of South Australia
Hylaeus is the only globally distributed genus in the bee family Colletidae, but generic diversity highest in Australia. We use Bayesian analyses to recover the phylogeny of this genus, based on species from Australia, Asia, Africa, Europe, Hawai’i, the New World and New Zealand. We find an Australian origin about 30 Mya. We also show there have only been two dispersal events out of Australia, both shortly after its crown age. One of these dispersals was into New Zealand with only a minor subsequent radiation, but the second dispersal resulted in a remarkable world-wide distribution. This second dispersal and radiation event, combined with very extensive early radiation of Hyleaus in Australia, poses a conundrum: what kinds of factors could simultaneously drive global dispersal, yet strongly constrain further successful migrations out of Australia when geographical barriers appear to be weak? We argue that for hylaeine bees movement into new niches and enemy-free spaces may have favoured initial dispersal events, but that subsequent dispersals were impeded by niche pre-emption.
A South American Perspective on Holocene Southern Hemisphere Westerly Wind Variability
Christopher Moy, Geology Dept., University of Otago
Robert Dunbar, Dept. of Environmental Earth System Science, Stanford University
Patricio Moreno, Instiotute for Ecology and Biodiversity, Universdiad de Chile
Thomas Guilderson, Institute of Marine Sciences, University of CA – Santa Cruz
The Southern Hemisphere westerly winds play a fundamental role in global climate by mediating air-sea gas exchange in the Southern Ocean through wind-induced upwelling of deep water. Despite global relevance, our understanding of Holocene westerly variability and its potential influence on the global carbon cycle is limited. Here, we reconstruct Holocene changes in the strength of the westerlies at a latitude where the winds play a fundamental role in the hydrographic processes responsible for deep water ventilation in the Southern Ocean. We utilize highly resolved and well-dated lacustrine geochemical sedimentary records from SW Patagonia and Tierra del Fuego to monitor changes in hydrology and lake dynamics associated with the overall strength of the Southern Hemisphere westerlies. Multiple proxies imply moderately strong westerlies during the Late Glacial/Holocene transition, followed by an overall reduction in wind intensity during the early Holocene between 9,000 and 6,000 cal yr BP, which is followed by a gradual increase in strength that culminates within the last 400 years of our records. The Holocene changes observed in these records are broadly synchronous with the timing of CO2 variations recorded in Antarctic ice cores; taken at face value, this covariance suggests a westerly influence on the carbon cycle. Our westerly wind variations also appear to be synchronous with shifts in Northern Hemisphere temperature and tropical climate at millennial and multi-millennial timescales, which suggests that the processes linking high latitude climate of both hemispheres during glacial terminations may also operate during the Holocene.
Above- and below-ground carbon storage in tall snow tussock grasslands, New Zealand
Luitgard Schwendenmann, The University of Auckland
Katharine JM Dickinson, University of Otago
Alan F Mark, University of Otago
Around 1.2 million ha of tall snow tussock (Chionochloa rigida) grasslands are remaining in New Zealand. Studies have highlighted the importance of this tussock for ecosystem services, especially water yield. Another ecosystem service that is of increasing interest is carbon storage within biomass and soil. The aim of this study was to quantify the above- and below-ground carbon storage of two snow tussock sites (Glendhu and Black Rock) in the Lammerlaw Range, south-central New Zealand. We used the point-centred quarter (PCQ) method to estimate density of tussocks, height, basal area, and number of tillers per tussock. Above-ground carbon storage (separated by live shoots, dead blades/sheaths, and litter) was estimated by harvesting a number of tillers per tussock (n = 11), collecting litter, drying the material and determining the carbon concentration of each tissue type using an elemental analyser. Soil samples were taken at 10 cm intervals to 30 cm depth and analysed for carbon. Carbon storage in above-ground biomass at Glendhu was 34 t C ha-1. Soil carbon concentration was high across the profile with up to 11% in 0-10 cm and 5% in 20-30 cm. Total soil carbon stored underneath tall snow tussock (0-30 cm depth) ranged between 100 and 150 t C ha-1.The magnitude of these soil carbon stocks is comparable to that stored under natural NZ forest and highlights the importance of this ecosystem as a potential carbon sink.
Adaptive foraging in a giant alpine insect, the Otago stone weta
Priscilla Wehi, Massey University
Maia Mistral, Universityof Otago
David Raubenheimer, Massey University
Mary Morgan-Richards, Massey University
A key step in building links between nutrition and communities is clarifying how nutritional challenges affect the expression of ecologically relevant traits. The Otago stone weta (Hemideina maori) is a large Orthoperan insect that inhabits subalpine and alpine regions of the South Island, New Zealand, and shows substantial size variation across geographic locations. Previous work has shown a greater degree of omnivory in these weta than in other species in the genus, and researchers have also hypothesised that weta might target lipid rich plants. Otago stone weta Hemideina maori were collected from six locations for a comparative study of adult size, diet, and vegetation. We used nutrient analysis on the contents of their crop and hindgut to examine evidence of variation among meals, and stable isotope analysis of femur muscle to determine long term variation in their diets. In addition, we sampled vegetation from four 15m transects at each capture site to quantify abundance of plant species. Isotope and nutrient analyses from the weta crops varied substantially with location, as did plant species abundance and adult weta size. We discuss our findings in relation to a nutrient limitation framework, and adaptive foraging in this alpine insect species.
Alpine ecosystems under global change
Christian Körner,, University of Basel, Switzerland
The alpine life zone is the only 'biome' found across the globe at all subpolar latitudes. By definition too cold for tree growth, it assembles similar plant functional types or life forms, hence is ideally suited for global comparisons. While life in the alpine is often considered constrained by stress and resource limitation, the reality is that most alpine species would disappear if these presumed constraints would be removed, thus questioning the usefulness of agronomic limitation concepts in an ecological and evolutionary context. Building upon this rationale, I will discuss the likely impacts of global change factors such as climatic warming, changing precipitation regimes, elevated atmospheric CO2 concentrations, enhanced nitrogen deposition and land use change on alpine plant communities. Of these, land use and soluble N deposition are likely the most influencial factors in many regions. Neither elevated CO2 itself, nor changes in precipitation are likely to have significant effects at high elevation, exept when drought induced fires come into play. Climate warming needs to be seen in a microclimate context, with topography exerting an overarching influence likely to mitigate overall effects on biodiversity, as it did in the geological past (alpine refugia). In fact, thanks to their topography driven habitat diversity, high mountain ecosystems and their biological richness are likely to be more robust against climatic change than most other types of ecosystems, and thus, will play an increasing role in nature conservation.
Ambers of Gondwanan origin – rare or unexplored windows into terrestrial paleoecosystems?
Alexander Schmidt, Georg-August-Universität Göttingen, Courant Research Centre Geobiology,
Preservation in amber is renowned for its microscopic fidelity, including cells and organelles. The discovery of amber inclusions is important for tracing the evolutionary history of lineages with otherwise poor fossil records through time, and also for elucidating the diversity of terrestrial paleoecosystems. Amber is found in hundreds of Old and New World localities; however, it does not occur equally in time and space. The fossil record of resins begins in the Carboniferous and has a first global occurrence in the Late Triassic. Most amber deposits have been discovered in Cretaceous to Miocene strata of the Northern Hemisphere. Hypotheses for massive resin production at intervals in the geological record include the advent of certain new conifers or wood-infesting insects, paleoclimatic changes, wildfires, or any combination of these. Until recently, Cretaceous Lebanese and Jordanian ambers were considered the only relevant fossiliferous resins of Gondwanan origin. However, discoveries within the past decade have revealed Triassic to Miocene ambers from many other places such as Argentina and Lesotho (Triassic), Brazil, Ethiopia and South Africa (Cretaceous), Australia and New Zealand (Cretaceous to Miocene) as well as from India (Eocene) and Peru (Miocene). None of these deposits matches the volume of Baltic or Dominican amber, so far, but even minute occurrences deserve attention. Recently, it has become obvious that amber of the Southern Hemisphere is neither rare nor unfossiliferous. These previously neglected amber outcrops, such as those from New Zealand, are providing an abundance of inclusions, from bacterial cells to arthropods.
AMPHIBIANS, STRESS AND DISEASE AT HIGH ELEVATION: IMPLICATIONS FOR UNDERSTANDING RESILIENCE TO CLIMATE CHANGE
Jean-Marc Hero, Environmental Futures Centre, School of Environment, Griffith University, Gold Coast campus, Qld 4222 Australia
Christina Kindermann, Environmental Futures Centre, School of Environment, Griffith University, Gold Coast campus, Qld 4222 Australia
Clara Graham, Environmental Futures Centre, School of Environment, Griffith University, Gold Coast campus, Qld 4222 Australia
Billy Ross, Environmental Futures Centre, School of Environment, Griffith University, Gold Coast campus, Qld 4222 Australia
Hamish McCallum, Environmental Futures Centre, School of Environment, Griffith University, Gold Coast campus, Qld 4222 Australia
Edward Narayan, Environmental Futures Centre, School of Environment, Griffith University, Gold Coast campus, Qld 4222 Australia
Globally, enigmatic amphibian population declines have been concentrated at high elevations, independent of latitude. Explanations have been linked to climate change and the pathogenic fungus Batrachochytrium dendrobatidis (Bd), however the links between these two factors are poorly understood. Climate change threatens amphibians restricted to mountain tops, as the cooler environmental conditions at high elevation are optimal for the growth and development of mountain-top endemic frog species, hence they are vulnerable to increasing temperatures. Cooler montane environments are also optimal for the growth of the pathogenic fungus Bd. Here we present the first physiological evidence suggesting 1) frogs with high intensity of Bd have higher baseline stress hormone levels, and 2) frog populations at higher elevation have increased stress levels (elevated baseline corticosterone levels in urine) compared to their lowland counterparts. Prevalence of Bd zoospores from frog skin swabs was quantified using a real-time quantitative PCR technique. Individual male frogs that were identified as positive for Bd infection had significantly higher baseline urinary corticosterone concentrations in comparison to Bd negative male frogs. Baseline urinary corticosterone concentrations were also significantly higher at high altitude sites (P<0.001). These results, suggest frogs at higher elevation are stressed and hence more susceptible to the impacts of Bd than their lowland counterparts. So which factor is responsible for the extinction of frogs at high elevation ? and, who came first - the stress or the disease ?
Antarctic meiofauna: a first step in understanding molecular operational taxonomic units (MOTUs) and biogeography of cryptic fauna
Mark Stevens, South Australian Museum
Alejandro Velasco Castrillon, University of Adelaide
Paul Czechowski, University of Adelaide
Byron Adams, Brigham Young University
Cyrille D’Haese, Museum National d'Histoire Naturelle
John Gibson, University of Tasmania
Sandra McInnes, British Antarctic Survey
Chester Sands, British Antarctic Survey
Recent studies have suggested that some resident Antarctic biota are of ancient origin and may have been isolated for millions of years. A major component of the Antarctic terrestrial meiofauna primarily consists of nematodes, tardigrades, rotifers and springtails. However, the latter is the only group examined using molecular markers but these groups are some of the few widespread Antarctic terrestrial animals that have the potential to be used as models for evolution and biogeography on the Antarctic continent. Of particular interest are the groups that possess an impressive array of biochemical abilities to withstand harsh environmental conditions and here we contrast the tardigrades and nematodes (that have an apparent greater dispersal capability) to springtails (with a lesser dispersal capability). We isolated individuals from geographically isolated soil samples from the remote nunataks in the Sør Rondane Mountains, Dronning Maud Land, Antarctica, and examine genetic variation among individuals to other Antarctic and sub-Antarctic regions using nuclear and mitochondrial DNA. These comparisons indicated long term survival and isolation over glacially dominated periods in ice free habitats in the Sør Rondane Mountains, and implies similar patterns across much of the terrestrial Antarctic continent.
Are Asteraceae 1.5 billion years old? A reply to Heads
Ulf Swenson, Swedish Museum of Natural History
Stephan Nylinder, Swedish Museum of Natural History
Steven Wagstaff, Allan Herbarium, Landcare Research
Divergence time estimates have become more widely used and add intriguing perspectives in understanding the distribution of the world's biota. Fossil age, island age, and ages of tectonic events can all be used to calibrate phylogenies. In a recent paper in Systematic Biology, Michael Heads raised critiques against the use of islands as maximum age and instead proposed that tectonic calibration supersedes fossil calibration. Among his examples is Abrotanella, a small Asteraceae genus distributed in the Southern Hemisphere. Heads has advocated that the genus was present in Gondwana before the break-up, and that during the history of the angiosperms, the present distribution resulted from continental rifting, fracturing, and accretion. In a reply to Heads, we tested his ideas by using BEAST, four different prior distributions, fossil versus tectonic calibration, and report 95% highest posterior density intervals (HPD). We demonstrate that fossil calibration, despite using a 38- or 47.5-myr-old fossil, reconcile with long-distance dispersal, establishment, and diversification. If Heads ideas of vicariance in Abrotanella are true, the age of Asteraceae must be 1.5 billion years, a time when the biosphere was nearly exclusively populated by microscopic marine organisms. We conclude that a priori tectonic calibration on sister relationships as if they represent alleged vicariance events is a bad idea.
Are ecological ghosts haunting New Zealand? Native plants respond to functional analogues of extinct megafauna
Andrew J Tanentzap, York University
William G Lee, Landcare Research, University of Auckland
Adrian Monks, Landcare Research
Ecological processes often maintain the biological communities with which they have a long evolutionary history, so these processes may remain imprinted in communities even after their sudden loss. Although interpreting the importance of ecological processes through paleoecological reconstructions is valuable, environmental histories are frequently debated and require contemporary tests in the field. Here, we test whether the shared history between New Zealand’s native plants and its extinct, avian megafanua remains expressed in the responses of native plants to browsing and grazing animals, and their effects on N cycling. Using vegetation surveys, we find that selection of woody plants in New Zealand forests and shrublands by introduced herbivores is largely explained by plant phylogeny, as expected where defences co-evolved with megafauna. Experimental simulations of fecal deposition and soil turnover by extinct megafauna further reveal that seedling regeneration in a temperate rainforest is stimulated by soil-available NO3- derived from hen manure, an avian source with distinct chemistry from mammalian feces. Although hen manure also increased soil P, concentrations also increased within plots treated with a commercial liquid fertilizer, which did not increase seedling densities; soil disturbance elicited no effect. Finally, we found that pre-treatment NO3- levels, which reflected longer-term N cycling, reduced non-native plant invasion. Our findings suggest that avian-derived N inputs promote native forest regeneration, raising the question of whether the functional role of extinct megaherbivores is absent in New Zealand. Modern surrogates for extinct, avian megafanua may help sustain and restore ecological processes, thereby supporting biodiversity conservation.
Are Sapotaceae supporting or rejecting the notion that New Caledonia is a very old Darwinian island?
Ulf Swenson, Swedish Museum of Natural History
Stephan Nylinder, Swedish Museum of Natural History
Jérôme Munzinger, IRD, UMR AMAP, Montpellier
New Caledonia is an isolated archipelago in the west of the Pacific Ocean considered of continental origin with a biota stemming back to Gondwana. However, geological evidence clearly indicate that New Caledonia was submerged during millions of years and returned subaerial around 37 Ma and first then available for re-colonization and terrestrial evolution. We have derived divergence time estimates of a monophyletic clade of Sapotaceae (Chrysophylloideae) by using BEAST, a sample of 167 terminals, and different modes of calibration to test which hypothesis can be reconciled with its distribution. This clade has a centre of distribution in New Caledonia, New Guinea, and Australia, but extends to French Polynesia in the east and to continental Southeast Asia in the northwest. Our fossil-calibrated estimates are conclusive in that no lineage of Sapotaceae reached New Caledonia before 37 Ma. Instead, the territory has been colonized nine times with splits from the nearest ancestor at 8 Ma for Pleioluma, 27 Ma for Pycnandra, and 31 Ma for Planchonella. Safe splits for each genus within New Caledonia are estimated to 5, 16, and 17 Ma, respectively. Planchonella baillonii is sister to all congeners, endemic to New Caledonia, and diverged from its sister some 40 Ma, but the analysis reject New Caledonia as the area of origin. We conclude that this species arrived there later in the history and became extinct in its area of origin. Colonization into the Pacific follows a sequential order with the youngest splits among the youngest oceanic islands.
Are the tussock grasslands of Mount Tongariro scared of heights, volcanic eruptions or both?
Matthew Aaron Krna, Massey University
Jill Rapson, Massey University
Surinder Saggar, Massey University; Landcare Research
Kevin Tate, Landcare Research
Hannah Buckley, Lincoln University
Aside from the recent fright caused by Mount Tongariro's 2012 eruption, these tussock grasses (Chionochloa rubra) may also be scared of heights. This alpine environment imposes a wide gradient of abiotic threats, and is also near an active volcanic centre. Eight plots spanning 700m in altitude (spaced at ≈100m elevations) were established in February 2010 to investigate in situ productivity of C. rubra. Litter decomposition was also investigated via a full reciprocal translocation experiment, as part of climate change investigations.
Higher altitude results in lower growth and reproduction of C. rubra, as well as higher dieback and resistance to decomposition. These findings are comparable with results for Chionochloa elsewhere in New Zealand and for species in other grassland systems. Soils at the higher altitude plots have lower nitrogen concentrations and higher carbon to nitrogen ratios (C:N), while recently dead (i.e. initial) leaf litter shows the reverse trend, perhaps due to differences in storage dynamics. Lower C:N generally suggests higher litter decomposability. However, results for decomposition after 1 year showed less decomposition of litter translocated both to and from higher elevations. This discrepancy in decomposability could be due to secondary metabolite composition of the litter, or is possibly a consequence of deposition of chemicals from nearby volcanic sources.
Altitude influences carbon and nutrient dynamics in these tussock grasslands. Climate change and ash deposition may also influence these cycles. Future research could investigate how the tussock grasslands are affected by Mount Tongariro’s recent eruption.
Assessing the impact of human settlement and historic hunting on the New Zealand sea lion, Phocarctos hookeri, using ancient DNA analyses
Catherine Collins, Univsersity of Otago
Michael Knapp, University of Otago
Bruce Robertson, University of Otago
Lisa Matisoo-Smith, University of Otago
Jon Waters, University of Otago
The impacts of human arrival in coastal New Zealand remain poorly understood. The New Zealand sea lion, Phocarctos hookeri, has a geographically restricted distribution compared to the prehistoric population prior to human arrival here. The modern breeding population is centred on the subantarctic Auckland Islands and Campbell Island, with a very small population having recolonised the Otago Peninsula over the last two decades. However, archaeological evidence indicates that NZ sea lions were previously distributed throughout coastal New Zealand. The extirpation of P. hookeri from most of mainland New Zealand apparently occurred soon after Māori settlement, with final mainland extirpation driven by the arrival of European sealers in 1769. I use ancient DNA (aDNA) analyses of archaeological and pre-human specimens, ranging in age from 600 years BP up to 5000 years BP, to develop our understanding of the impact that human settlement has had on New Zealand’s native coastal fauna. Comparisons of mitochondrial control region sequences of prehistoric versus modern populations indicate that the subantarctic lineage was previously absent from mainland New Zealand. These data suggest a pattern of anthropogenic mediated extinction-recolonisation mirroring that seen in Megadyptes penguins.
Baltic amber, extinction and the problem of “pseudo-Gondwanic” distributions
Daniel J. Bickel, . , Australian Museum, 6 College Street Sydney NSW 2010
In the absence of historical evidence, biogeographic interpretation must, of necessity, rely on recent distributions. Quite simply, for most organisms, fossil evidence is either fragmentary or non-existent. However with reliable fossil evidence, current distribution may not be what they seem to be. This talk with focus on Atlatlia (Diptera: Dolichopodidae), a tiny fly genus common on tree trunks, and particularly well-defined by several strong synapomorphies. The genus occurs in New Caledonia (3 spp.) and in a classical Australian Bassian distribution, disjunctly between southeastern (2 sp.) and southwestern Australia (1 sp.). Such a pattern normally would be regarded as supporting a Gondwanan origin for the genus. However, three unmistakable Atlatlia species are now known from the late Eocene- Oligocene Baltic amber, indicating this genus was once widespread, and extinction is responsible for its current “Pseudo-Gondwanic” distribution. Other examples of Pseudo-Gondwanic distributions are presented, as well as a brief review of the extraordinary fossil richness of Baltic amber. In conclusion, extinction must be regarded as important a process as vicariance and dispersal to explain current biogeographic distributions.
Basic research supporting wilding conifer management in NZ
Thomas Paul, Scion
Nick Ledgard, Scion
Ian Dickie, Landcare Research
Duane Peltzer, Landcare Research
Basic research on wilding conifers in NZ has been carried out since the 1980s, mainly by Scion and Landcare Research. Early research focussed on the life history of wildings, mainly seed production, dissemination and longevity of seed viability in soils, plus seedling survival and microsite preferences. In 2007, a Wilding Conifer Management Group was formed, mainly to oversee a govt-funded research programme looking at three topics; inventorying wilding-affected areas and assessing spread risk, control options and vegetation changes associated with wilding control. Inventory data proved to be difficult to collect and variable, and remains incomplete. Results from the earlier life history research were incorporated into spread risk decision support systems, plus the information has been developed into spatial models utilising Google Earth imagery. Different control techniques were found to lead to different vegetation outcomes, with some proving complimentary to enhancing a return to indigenous woody plant covers. Independently, Landcare Research has focused on ecosystem effects of invasion, and post-removal legacies. Despite the presence of many species of native ectomycorrhizal fungi, wilding conifers co-invade with a limited community of non-native fungi. At the ecosystem scale, the invasion of wilding conifers causes both positive and negative effects on ecosystem services, enhancing above-ground carbon sequestration but causing significant losses of diversity, particularly below ground. Wilding conifers also cause significant shifts in soil nutrient cycling. These results raise concerns about the below-ground legacies of wilding conifers and how these may influence post-removal ecosystem recovery.
Beyond Gondwana: How similar are the non-native floras of New Zealand and Chile?
Anibal Pauchard, Universidad de Concepcion - Institute of Ecology and Biodiversity
Aurora Gaxiola, Institute of Ecology and Biodiversity
Ian Dickie, Landcare Research
Peter Williams, Landcare Research
Duane Peltzer, Landcare Research
Ramiro Bustamante, Institute of Ecology and Biodiversity
Hazel Gatehouse, Lincoln University
Pablo Marquet, Institute of Ecology and Biodiversity
STERN-members, Southern Temperate Ecosystem Research Network
Whether regions with similar climatic may harbor similar non-native floras is an open question in invasion ecology. New Zealand and Chile share similar temperate climatic regions, but differ importantly in introduction effort, historic and current land use and native biota. We have tested whether the non-native floras of climatically similar areas of Chile and New Zealand converge or diverge in the last century and have identified the main factors that determine regional similarities and differences. We compared a list of 644 non-native species for Chile and 2246 for New Zealand, compiled from herbarium records and databases. We found that although more than 65% of the non-native species of Chile can be found in New Zealand, Chile has some unique non-native flora. New Zealand shows a much more diverse non-native flora reflecting a long and intensive history of introductions from a wide arrange of continents, while Chilean non-native flora is mostly European. Population and road density explain the concentration of non-native species in specific regions of New Zealand and Chile. Taxonomic similarities for regions within a country are much higher than between regions of both countries, even when only species shared between the two countries are analyzed. This strong differentiation is explained by completely different histories of introductions and land use. Indeed, total similarity between the non-native floras of Chile and New Zealand has decreased in the last decades, a pattern that may change with increasing globalization. AP funded by ICM P05-002 and CONICYT PFB-23.
Bio-Climatic Zonation in the Subantarctics and likely Consequences of Climate Change
Colin D Meurk, Landcare Research NZ Ltd
In 30 years since proposing a bio-climatic typology for NZ and its southern islands, consistent with well-established boreal systems, human-induced climate change has become an accepted reality, and Peter Wardle brought another reality to growth-form-defined zones in NZ compared to continental South America. The weaknesses in NZ zonation are genetic (small gene pool without continuous Palaearctic-like history); geological (recency); oceanic (accounting for >1.5°C discrepancy in tree line climate); and (depressed) summit caused. One northern hemisphere reference in subantarctic NZ is a lone sitka spruce on Campbell Island. It took nearly a century to attain the height of local Dracophyllum bushes (5m in sheltered gullies), but is now 8-9m tall. This suggests that, as per Wardle’s penalpine zone, and notwithstanding the oceanicity effect, NZ’s subantarctic scrub and tall tussock represents a southern ‘subalpine’ rather than ‘low alpine/arctic’ as such growth-forms would be characterised in northern continental environments.
A simple extrapolation of climate driven zonal shift is likely to propel some upland endemic species to extinction as woody vegetation ascends the hills (perhaps 300m); pest species expand; sea currents and up-wellings move away from island nesting sites, in turn affecting marine subsidies to terrestrial environments. From a vegetation perspective, there will need to be greater vigilance to prevent woody and herbaceous weeds getting onto these islands and exploiting warmer conditions. Suspects include Ulex, Cytisus, Betula, Salix and Calluna shrubs, tall grasses like Arrhenatherum, Schedonorus and Dactylis, and the leguminous Lotus.
Biogeographical history of Austrocedrus chilensis on the eastern Patagonian Andes
Virginia Iglesias, Montana State University
Cathy Whitlock, Montana State University
In the eastern Patagonian Andes, Austrocedrus chilensis is a dominant species at the lower treeline, reaching its eastern distribution in the foothills of the mountains, where open woodland gives way to steppe. During the Last Glacial Maximum, ice sheets covered the current habitat of Austrocedrus, except for possible areas at glacial margins and unglaciated interfluves. Palynological evidence suggests the presence of the species on both sides of the Cordillera, raising the question of which colonization route(s) the species followed to reach its present-day distribution in Argentina. Four scenarios are possible: 1) a southward migration from a northern refugium, where effective moisture would have been higher than in the steppe; 2) an eastward migration from Chilean or high-elevation refugia; 3) a westward migration from one or more refugia in the steppe; and 4) a combination of these. To test these hypotheses, we collected sediment cores from seven lakes along the forest-steppe ecotone and used high-resolution pollen and charcoal analyses to reconstruct the Holocene vegetation and fire history of the area. Our results indicate that the species was present in the Nahuel Huapi region as well as in the steppe at lat. 42°S as early as 10,000 cal years BP, supporting the existence of multiple glacial populations. The Holocene expansion of Austrocedrus was a response to the interplay between climate change and shifts in the fire regime, suggesting that the current distribution of the species results from present-day ecological factors as well as historical events.
Biogeography and Phylogeny of Cicada tribes Worldwide as a Model for the Spread of Cenozoic Biodiversity
Chris Simon, EEB UConn
Kathy Hill, EEB UConn
David Marshall, EEB UConn
Ben Price, EEB UConn
Chris Owen, EEB UCONN
Geert Goemans, EEB UConn
Martin Villet, Rhodes University, South Africa
Max Moulds, Australian Museum
Thomas Buckley, Landcare Research NZ
The biogeography of the family Cicadidae worldwide can be used as a model for the origin and transcontinental spread of Cenozoic insect biodiversity. Although the phylogeny of the family is not yet complete, preliminary conclusions include: 1) new tribal placements for many genera, with some changing subfamilies; 2) support for the new three-subfamiliy scheme of Moulds (2005); 3) support for and differences from other aspects of the morphological cladogram of Moulds (2005); and 4) new clues to the relationships of problematic African cicada taxa. We have also made excellent progress in creating phylogenetic trees for major tribes within subfamilies, and genera within the larger tribes. It appears that most differentiation is Cenozoic and that Centers of diversification for the various tribes seem to be concentrated in different continents (some northern hemisphere, some southern) with later invasion of other parts of the world from the various centers of origin.
Biogeography of Calceolaria L. (Calceolariaceae) - continuous diffusion patterns in the Andean mountain range
Stephan Nylinder, Swedish Museum of Natural History, Stockholm, Sweden
Ulf Swenson, Swedish Museum of Natural History, Stockholm, Sweden
Bernard E. Pfeil, Department of Biological and Environmental Sciences, Gothenburg University, Sweden
Christine Ehrhart, 3Department of Biology, Ludwig-Maximilian University, Munich, Germany
Alicia N. Sersíc, 4Instituto Multidisciplinario de Biología Vegetal, Universidad Nacional de Córdoba, Argentina
Andrea Cosacov, 4Instituto Multidisciplinario de Biología Vegetal, Universidad Nacional de Córdoba, Argentina
Pamela Puppo, 5Plant Evolution Group, University of Porto, Portugal
Philippe Lemey, 6Department of Microbiology and Immunology, Katholieke Universiteit Leuven, Belgium
Bengt Oxelman, Department of Biological and Environmental Sciences, Gothenburg University, Sweden
What came first: the chicken or the egg? It has been debated whether radiation of plants in the Andes preceded the uplift of the mountain range itself, or if ancestors to present day species dispersed onto and diversified on the emerging or already established mountains. Here we apply a time calibrated continuous diffusion model implemented in BEAST for geographic distributions in three dimensions (longitude, latitude, and altitude) to a plasmid phylogeny of Calceolaria. We infer that the genus originated at ~13 Ma in lowland areas (at approximately 500 m alt) of central Chile, at a time when the Andes were much lower than present day. The primary radiations took place in Chile and Argentina, and in the rising mountain range in Bolivia with subsequent leaps toward northern Peru. A second wave of radiation took two separate directions, one from northern to southern Peru and another further to the north across the Huancabamba deflection. The timing of the radiation closely follows the uplift of the Andes, showing patterns of establishment in areas after suitable habitats and altitudes have become available. Our analyses identify two main hotspots as important stepping-stones for subsequent colonization of the Andes, namely the southeastern region of the Altiplano in Bolivia, and south of the Huancabamba deflection in northern Peru. The latter area is one of the most species rich in the entire Andean mountain range and hosts a range of Calceolaria species, many of which are very narrow endemics.
Biogeography of the New Zealand grassland weevil genus Irenimus
Samuel Brown , Lincoln University
Karen Armstrong , Lincoln University
Rob Cruickshank , Lincoln University
Craig Phillips , AgResearch
Barbara Barratt , AgResearch
The weevil genus Irenimus is endemic to New Zealand, and is one of the most speciose weevil genera in the country with approximately 50 species. The genus finds its highest diversity in the southern half of the South Island, particularly in the grasslands of Central Otago. It is likely that a number of species will be found to be localized endemics, and are thus of conservation and biogeographical interest. As part of a wider study on the taxonomy and evolution of the genus, the distribution of Irenimus species was determined. Ecological preferences for each species were inferred by comparing the distribution of each species against the Land Environments of New Zealand database. The phylogenetic relatedness of species that exist in sympatry was also evaluated. Preliminary results relating to the biogeography of Irenimus species will be presented, and discussed in terms of the implications for the evolution of the genus, as well as broader statements regarding the history of the South Island.
Bioregionalisation and evolutionary origins of freshwater Antarctic diatoms
Wim Vyverman, Ghent University
Elie Verleyen, Ghent University
Dominic Hodgson, British Antarctic Survey
We investigated biogeographical patterns and variation in species richness of freshwater diatom communities in ice-free regions of Antarctica and islands from the Southern Ocean. Our analyses are based on survey of 395 freshwater lakes from twelve lake districts located between 70°S and 45°S. Microscopic analysis resulted in a taxonomically consistent database containing diatom species abundance and spatial and environmental data. Multivariate analyses revealed a strong bioregionalisation into continental Antarctic, Maritime Antarctic and sub-Antarctic diatom floras. Local and regional diversity and the incidence of endemism scale with latitude and geographic isolation. Compared with similar lake districts in the Northern Hemisphere, Antarctic diatom floras are strongly disharmonic and dominated by lineages with a predominantly terrestrial distribution. Furthermore, molecular phylogenies based on the plastid gene rbcL and the nuclear 28S rDNA (D1-D3 region) revealed that two cosmopolitan morphospecies (Pinnularia borealis and Hantzschia amphioxys) both consist of multiple lineages, each including a distinct Antarctic lineage. A molecular clock estimate suggests that the Antarctic P. borealis lineage diverged 7.8 (2-15) Ma ago. Despite not being psychrophilic, the Antarctic lineages of P. borealis and H. amphioxys have a lower optimal growth temperature and upper lethal temperature than lineages from more temperate regions. Together, this suggests that many presumed cosmopolitan Antarctic diatom species are in fact species complexes, possibly containing Antarctic endemics with low temperature preferences. Analyses of Late Quaternary lake sediment records suggest a long-term stability of local and regional diatom floras, thus providing opportunities for local adaptation and significant allopatric speciation.
Bird conservation in last place on Earth
Mick Clout, School of Biological Sciences University of Auckland
New Zealand was the last habitable landmass to be settled by humans and their cargo of invaders, leading to the eventual loss or decline of many endemic species and to significant ecosystem changes. Introduced mammals are now recognized as the main threat to NZ native birds, and there have been significant advances in understanding and mitigating their impacts. Bird conservation efforts in New Zealand now focus especially on managing invasive mammals, including their eradication from islands and control at mainland sites. Recovery programmes for threatened native birds include reintroduction to mammal-free sites and intensive management. This talk gives a personal perspective on bird conservation in New Zealand, focusing on the impacts of invasive mammals and illustrated by examples such as the recovery programme for kakapo (Strigops habroptilus).
Burning tussock grasslands: effects on Amphipoda
Janine Wing , Dept of Botany, University of Otago
Barbara Barratt, AgResearch, Invermay Research Centre
Fire was rare in the pre human history of New Zealand, increasing significantly with the arrival of humans and the establishment of agriculture. Burning indigenous tussock grassland has been used extensively as an agricultural management tool in New Zealand to stimulate young palatable regrowth for stock and increase the success of oversown pasture species. There has been little research into the effects of burning in New Zealand tussock grasslands; less still on the effects of fire on invertebrates. Both farmers and conservation managers have recently sought to increase their understanding. This project focuses on the effects of burning in tussock grasslands in Otago on Amphipoda (Talitridae: Crustacea). Amphipods are detritivores existing in the litter layer, shredding decaying vegetation and are key recyclers of nutrients and carbon in the ecosystem. Terrestrial amphipods are highly susceptible to changes in humidity relying on behavioural mechanisms to control water loss. Burning removes the litter from the habitat on which amphipods rely for food and shelter, making these taxa a valuable bioindicator to the changes caused by fire. The long term data set reveals amphipod abundance has still not recovered to pre-burn levels in inter-tussock samples eleven years post burning. Evidence of large yearly fluctuations in abundance is apparent in control plots. Sampling targeted at revealing differences at the microhabitat level was used to determine possible explanations for the lack of recovery of amphipods in burnt plots.
Can Sporormiella help resolve the sequence of events in late Quaternary ecosystem change?
Janet Wilmshurst, Landcare Research
Jamie Wood, Landcare Research
For almost three decades spores of the dung fungus Sporormiella have provided a palaeoecological tool for detecting herbivore extinction and introduction events in sedimentary records. On a millenial scale the proxy seems to be an excellent predictor of these events. However, its accuracy at higher temporal resolutions remains poorly understood, as the abundance of Sporormiella spores is known to be influenced by environmental conditions at some sites. This is a problem that may limit the ability of Sporormiella to be used in conjunction with other palaecoecological proxies (e.g. pollen and charcoal) to resolve the sequence of events in late Quaternary ecosystem change. We show how correlating Sporormiella with moisture-related proxies (e.g. Cyperaceae pollen) can test the likely affect of environmental influences on spore abundance at a study site. Discounting a correlation between Sporormiella and moisture proxies in the pre-extinction period increases the confidence and resolution with which the timing of an actual extinction event can be determined.
Can temperate insects take the heat? The risks of high temperature exposure to meat ants caused by climate change.
Nigel Andrew, University of New England
Robert A. Hart, University of New England
Myung-Pyo Jung, National Academy of Agricultural Science, South Korea
John S. Terblanche, Stellenbosch University, South Africa
1. Insects in temperate regions are predicted to be at low risk of climate change owing to high thermal safety margins (low optimal performance temperature relative to habitat maxima) and/or high warming tolerance (high thermal tolerance relative to habitat maxima) relative to more tropical species. However, these assumptions have been generally poorly examined and such forecasting typically fails to account for microclimatic variation and behavioural optimization of insects.
2. Here, using Iridomyrmex purpureus meat ants from Armidale, NSW, we show that ants regularly forage for short periods (minutes) at soil temperatures well above their upper thermal limits determined over slightly longer periods (hours) and do not show any signs of a classic thermal performance curve in voluntary locomotion across 10-55°C.
3. Generally close associations of ant activity and performance with microclimatic conditions, possibly to maximise foraging times, suggest I. purpureus display highly opportunistic thermal responses and readily adjust behaviour to cope with extremely high trail temperatures. Increasing frequency or duration of high temperatures is therefore likely to result in an immediate reduction in foraging efficiency.
4. These results for a key functional group suggest that (1) soil-dwelling temperate insects may be at higher risks of extinction with increased frequency or duration of high temperatures resulting from climate change than previously thought; and (2) that indices of climate change-related extinction are strongly influenced by the scale of climate metrics employed.
Celebrating Progress in the Conservation and Protection of Indigenous Temperate Grasslands
Bill Henwood, Temperate Grasslands Conservation Initiative, IUCN.
Indigenous temperate grasslands are the most altered, most endangered, and least protected biome in the world. Almost 50% have been converted to other land uses, most notably agriculture, urban development and plantation forestry. In some cases, such as the tall grass prairie in North America, the grasslands of south-east Australia and the steppes of eastern Europe, the levels of conversion approach 98%. However, only 4-5% of this biome has been protected, far less than any other biome. The Temperate Grasslands Conservation Initiative (TGCI) was created to address this deficiency and to seek the protection of 10% of the biome by 2014, the year of the next World Parks Congress.
At the inception of the TGCI in 1996, the level of protection was less than 1%, so considerable progress has been made over the past two decades. But much remains to be done. A global assessment of temperate grasslands has identified the remaining opportunities for large landscape scale conservation and protection initiatives as well as the potential in the more altered landscapes. This paper reviews the progress made, and the various strategies employed to conserve and protect indigenous grasslands, toward reaching the interim target of 10% and the new Aichi target seeking effective conservation of 17% of all biomes.
Changes at sub-Antarctic Marion Island: factual, anecdotal and fantastical Valdon Smith
Valdon Smith, Department of Botany and Zoology, Stellenbosch University, South Africa
Changes that have occurred in the Marion Island ecosystem are discussed, from a perspective gained from visits to the island over 40 years. Some are documented and quantified, others anecdotal and some possibly just in the mind of the beholder. Changes that are addressed include abiotic, biotic and ecosystem-level ones. Examples where the changes have had, and are still having, a significant influence on ecosystem functioning are presented. The ecological forcing variables that shape the island's terrestrial and freshwater habitats, and how their relative strengths have changed, are described, as are the natural and human-mediated threats to the island's biota and ecosystem.
Changes in both temperature and precipitation affect plants at various stages of their life cycle, in alpine grassland ecosystems of Western Norway.
Pascale Michel, Department of Biology, University of Bergen
Vigdis Vandvik, Department of Biology, University of Bergen
Olav Skarpaas, The Norwegian Institute for Nature Research
Kari Klanderud, University of Life Sciences
Changes in both temperature and precipitation are predicted by future climatic scenarios, and their
interactive effects remain poorly understood. Within a climatic grid, we investigate alpine plant
responses to climatic change on well-established grasslands in Norway. Our results so far showed
that alpine plant recruitment, growth, biomass, resource allocation, and species composition are
affected by changes both in temperature and precipitation and species-specific responses can alter
competitive interactions in the future, favouring lowland and generalist species under warmer and
wetter climate, as predicted for the study region. Seedling establishment in intact vegetation
decreased by approximately 27% due to increased competition; and in bare-ground gaps, increased
by 51%, suggesting that disturbance may interact with climate to determine species distributional
shifts in the future. Effects on resource allocation, was dependent on plant size and functional
group. Both temperature and precipitation increased basic allocation to reproduction, but larger
plants invested less in reproduction in wet environments, where productivity and competition may
be higher. Increased precipitation reduced allocation to roots, as water and nutrients become less
limiting, and increased temperature reduced allocation to leaves, possibly due to increased
photosynthetic rates. Community composition was less determined by the abiotic and more by
biotic environment as temperature increased. Our results suggest that change in both temperature
and precipitation is likely to affect alpine plants, with effects emerging at several life cycle stages
and through complex micro-scale mechanisms. This may help explain the inconsistent climate
responses in studies that focus on warming effects alone.
Changes in the westerly winds: An investigation of Holocene wind variability using sedimentary and water column records from Fiordland, New Zealand
Jessica Hinojosa, University of Otago
Chris Moy, University of Otago
Claudine Stirling, University of Otago
Gary Wilson, University of Otago
The strength and latitudinal position of the Southern Hemisphere westerly winds play a major role in regulating Southern Ocean CO2 flux: modeling studies predict that winds centered over the Antarctic Circumpolar Current lead to CO2 outgassing, while when winds shift north, atmospheric CO2 is entrained in downwelling intermediate waters. Resolving past westerly wind variability is crucial for evaluating how the winds influence the Southern Ocean CO2 sink, yet broadly distributed paleoclimate records and conflicting interpretations amongst existing records currently limit our ability to do so. We are developing high-resolution records of Holocene westerly wind variability from sediment cores collected in selected sub-basins in Fiordland, New Zealand. Fiordland intersects the northern reach of the modern wind field maximum and offers basins yielding high-resolution sediment records of climate, environmental, and hydrographic change.
Using data from four sites in Fiordland, we characterized the physical oceanography of the fjords, the extent of anoxia, and the relative input of marine and terrestrial sources. From this preliminary work, we propose to track Holocene changes in the westerlies using proxies for precipitation and circulation within the fjords, and to evaluate intermittent variations in anoxic conditions related to changes in wind strength and circulation. We will present a stratigraphic record of C and N isotopes and discuss implications for Holocene variations at the northern margin of the westerlies. We will also present water column geochemical data, and discuss how trace-metal proxies can be used to characterize the modern water column and reconstruct past redox conditions from sediment cores.
Changing attitudes: towards a more sustainable forest management
Isabel María Gamondes Moyano , University of Otago
Richard Morgan, University of Otago
Guillermo Martinez Pastur , CADIC-CONICET
Intensive use of temperate forests over the centuries has caused a significant transformation of the resource in many parts of the world, particularly in forest structure and functionality. In this context, Sustainable Forest Management (SFM) has emerged as a comprehensive alternative to address concerns regarding resource use, nature conservation and socio-economic aspects. However, the application of SFM practices worldwide remains inconsistent.
Early in 2007, the National Forest Agency in Argentina passed Law 26331, setting a framework for native forest management with the objective of improving their use and conservation status through economic incentives and institutional promotion. The Patagonian province of Tierra del Fuego began to implement this SFM approach in 2012. The objective of this research is to understand which factors influence the implementation of SFM in Tierra del Fuego, Argentina, and to assess the perceptions towards the recently implemented regulatory reforms. Data was obtained from semi-structured interviews with the main stakeholders in the island, as well as with parties at a national level. The preliminary conclusions show that the historical mismanagement of the resource, together with an unfavourable past relationship with the authorities, have promoted short-term perspectives on the use of the resource and resulted in behaviours inconsistent with SFM. However, the sequencing of measures (information, incentives, controls) appears to play a significant role in the success of the recent policy implementation.
Changing climates, monsoonal floods and freshwater crocodiles
Ruchira Somaweera, Biologic Environmental Survey
Richard Shine, University of Sydney
Jonathan Webb, University of Technology, Sydney
In seasonal tropical environments, the magnitude and timing of monsoonal rainfall vary among years, with strong effects on plants, animals and their physical environment. In recent years, several tropical areas in Australia have experienced extreme rainfall events, resulting in devastating floods.Because extreme weather events are predicted to occur more frequently and strongly in a changing climate, we need to understand the pathways by which flooding influences the biota. Does flooding imperil aquatic species like crocodilians, and if so, why? In this study we examined how hatchling Australian freshwater crocodiles (Crocodylus johnstoni) inhabiting an anthropogenically modified system (Lake Argyle in Kimberley region, Western Australia) were affected by a heavy flood. We examined the changes in the structure and abundance of the preferred habitat of crocodile hatchlings (floating vegetation mats) and the relationship between the reduction of these habitats and the recapture rates as well as growth rates of hatchlings. We show that apart from the direct effects of damaging nests, monsoonal flooding degrades habitat quality, with devastating impacts on crocodile recruitment.
Climate and vegetation change over the last 3000 years in southern Chile and New Zealand
Patricio I. Moreno, Instituto de Ecología y Biodiversidad and Departamento de Ciencias Ecológicas, Universidad de Chile
Matt McGlone, Landcare Research
Southern Chile and New Zealand have many features in common: geography (tall, north-south trending mountain chains), climate (temperate, oceanic, westerly-influenced) and vegetation (dense, evergreen forests; prominence of Nothofagus and southern conifers). Their common latitudinal position and exposure to simultaneous forcing by solar insolation, sea surface temperatures of the southern ocean, fluctuations in the strength of the southern westerly winds, ENSO and the Southern Annular Mode should lead to strong similarities in both vegetation and climate trajectories. The last 3000 years provide an opportunity for a detailed examination of how this has worked out in practice. In New Zealand, the last 3000 years have seen rising tree lines, spread of Nothofagus, increased fire, wetter conditions in the east and, in general, a more variable continental climate. The Little Ice Age (LIA) and Medieval Climate Anomaly (MCA) are both well-established events. Closed-canopy rainforests dominate the western sectors of southern Chile with varying degrees of openness, abundance of hygrophilous trees, and paleofires that suggest centennial-scale changes in moisture delivered by the westerlies. The spatial and temporal phasing of inferred moisture anomalies suggest changes of the westerlies related to their strength (weaker during the MCA) or position (southward-shifted during the LIA). Our data suggest an all-time (Holocene) precipitation maximum in SW Patagonia (51°S) during the LIA, followed by a 20th century decline concomitant with large-scale disturbance by European settlers and spread of exotic invasive herbs.
Climate Change and Fire Regimes in Australian Temperate Eucalypt Forests: What Might Climate Change Mean for Risk Mitigation?
Richard J Williams, CSIRO Ecosystem Sciences
Ross A Bradstock, University of Wollongong
Stuart Matthews, CSIRO Ecosystem Sciences
Owen Price, University of Wollongong
Andrew L Sullivan, CSIRO Ecosystem Sciences
Penny Watson, , University of Wollongong
David MJS Bowman, , University of Tasmania
Neal J Enright, , Murdoch University
Geoffrey J Cary, Australian National University
A Malcolm Gill, Australian National University
We modelled the effects of climate change on critical determinants of fire regimes (fuel mass and moisture; rate of spread; area burnt) in the forests of south-eastern Australia. Here, fire regimes appear sensitive to climate change, there are significant natural and commercial assets, and there is debate concerning the extent to which prescribed burning reduces risk posed by unplanned fire. Modelling using climate change projections showed an increased frequency of warm-dry years to 2100, a modest decline in fuel mass, substantial changes to seasonal patterns of fuel moisture, and a longer fire season. Climate change will present novel opportunities and constraints for using prescribed burning: In warm-dry years there will be fewer opportunities in autumn and spring, but more in winter. Mitigation of risk will depend on ‘leverage’ – the reduction in area burnt by unplanned fire per unit area of planned fire. In south-eastern Australian forests, reducing area burnt by unplanned fire by 1 unit requires 3-4 units of prescribed fire. Modelling indicates that under climate change scenarios, significant increases in the area treated with prescribed burning will be required to achieve the same level of risk reduction that is achieved with current levels of treatment. Thus risk reduction in these forests will be partial under achievable levels of prescribed burning; there will always be residual risk. Increased treatment levels will involve higher management costs, and potentially increased risks to biodiversity. A robust framework is needed to evaluate various benefits and costs of landscape fire management.
Climate change and the thermodynamic niche of reptiles
Michael Kearney, The University of Melbourne
An important challenge in the study of climatic limits and adaptation lies in connecting measurements of climatic tolerance to life history consequences, and to do this in the context of natural microclimatic gradients. An increasingly rich array of spatiotemporal data on global environmental data has developed over the past 30 years. However, it is difficult to connect such data directly to empirical measurements of climatic tolerance, especially in terrestrial environments, because organsimal temperature and water balance are nonlinear functions of air temperature and humidity. In this talk I will show how thermodynamically-grounded models of heat exchange and metabolism can be integrated to meet these challenges, using a reptilian case study. Specifically, I will show how a formal metabolic theory, Dynamic Energy Budget theory (developed by Kooijman), can be combined with the biophysical models constituting the Niche Mapper package (developed by Porter). This integrated model, which I am implementing as an R package (‘NicheMapR’) can then be driven by high resolution climate data to determine acute (stress) and chronic (life history) responses of species organisms to climatic change. Such a modelling framework provides unique opportunities for understanding the causes and consequences of different climatic adaptations at different spatial scales in the past, present and future.
Climate Change, Fire and Australia’s Alpine Grasslands: Resilience or Doom and Gloom?
Richard J Williams, CSIRO Ecosystem Sciences
James C Camac, University of Melbourne
Ary A Hoffmann, University of Melbourne
Ian M Mansergh, Department of Sustainability and Environment
Warwick A Papst, La Trobe University
Carl-Henrik Wahren, La Trobe University
Australia’s alpine landscapes have high conservation significance. Global warming threatens alpine ecosystems worldwide, and Australia’s alpine grasslands face the potential twin stressors of a warming, drying climate and altered fire regimes. Alternatively, because alpine grasslands have experienced gross environmental change over successive glacial cycles, they may be resilient to the effects of fire and climate change. We present data from long term monitoring, and a medium-term warming experiment to test these hypotheses. Landscape scale fire did not cause deleterious effects on plant diversity. In the climate change experiment, grass cover declined due to drought, but there was no decline in species diversity or transformational change in species composition due to warming. Severe drought in the early 21st century caused substantial mortality in snow grass tussocks, and a 25% reduction in grass cover. The effects of experimental warming and burning on diversity and composition in grasslands were all within the range of temporal and spatial variation measured at multiple reference sites since 1979. We conclude Australia’s alpine grasslands are highly resilient to fire, and may also be resilient to a 1-2 degree C increase in mean growing season temperature over the coming decade. Directions and rates of change due to climate change and fire are not currently within the domains of concern that may require management interventions. Scarce resources will be better-directed towards managing other potential deleterious effects of global change on the conservation values of Australia’s alpine grasslands, such as the spread of exotic plants and animals.
Climate change: messages for applying communications of the science.
Angela Wardell-Johnson, Sustainability Research Centre, University of the Sunshine Coast
Lisa Ernoul, Tour du Valat Research Centre, France
Christopher Evans, Curtin Business School, Curtin University
Christine Storer, Curtin Business School, Curtin University
Collaborative approaches that acknowledge the role of local people in the context of landscape management are now widely advocated in the conservation of biodiversity. Climate change is now a significant impact on biodiversity but remains contested and controversial. Much depends on the conservation of biodiversity in multi-functional rural landscapes that are home to a diverse range of people and interests. Messages on mitigation, adaptation and intervention depend on the context of socio-cultural implementation to be receptive. This research reports on key positions and potential pathways for more effective communications about climate change in multifunctional landscapes in the south west of Western Australia, The Camargue in France, and the Gediz Delta in Turkey. These pathways are defined by results of surveys into how people understand climate change, use sources of information on climate change and how they value biodiversity. Climate change science is problematic for a broad range of people, while biodiversity is highly valued. This research demonstrates the critical importance of understanding social context and the influence of communications in the application of changes to manage the impact of climate change.
Climate Variability and Altered Fire Regimes Reduce the Resilience of Mountain Forests of British Columbia, Canada
G.A. Greene, University of British Columbia, Vancouver, BC, Canada
L.D. Daniels, University of British Columbia, Vancouver, BC, Canada
E. Da Silva, University of Guelph, Guelph, Ontario, Canada
J.D. Cochrane, University of British Columbia, Vancouver, BC, Canada; Carleton University, Ottawa, Ontario, Canada
H. Marcoux, University of British Columbia, Vancouver, BC, Canada
J. Nesbitt, University of British Columbia, Vancouver, BC, Canada
Z. Gedalof, University of Guelph, Guelph, Ontario, Canada
S. Gergel, University of British Columbia, Vancouver, BC, Canada
M.J. Pisaric, Carleton University, Ottawa, Ontario, Canada
C.J. C.Mustaphi, Carleton University, Ottawa, Ontario, Canada
Understanding the relationships between wildfire and environmental change is a fundamental concern, particularly in forests near the wildland-urban interface where human lives and property are at risk. In this research, we compared fire history and forest dynamics in the East versus West Kootenay areas of southeastern British Columbia. In both areas, fire regimes varied significantly with steep elevational gradients. At high elevations, stand-replacing fires burned every 150-300 years according to our lake sediment, fire scar and forest age results. In the lower-elevation forests, low-severity fires burned and scarred trees once every 25 to 50 years, on average. Fires burned in late summer of drought years, often during the warm phase of the Pacific Decadal Oscillation, associated with warm, dry conditions in the Kootenay region. Despite the historic frequency of fires and recent periods of suitable climate, these forests last burned 56 to 159 years ago, evidence of the effects of fire exclusion and suppression during the 20th century. The lack of recent fires was reflected in the composition and density of low-elevation forests in both study areas. Understanding past climate variation helps us anticipate the potential effects of future climate change. Historically, fires were most likely to burn during single-year droughts in the warm, dry phase of the Pacific Decadal Oscillation. These results suggest that subtle changes in climate that increase drought may increase fire frequency. As well, fires in low-elevation forests may shift towards higher-severity given current forest composition and densities that are perpetuated by fire suppression.
Climatic niche conservatism in Nothofagus genus
Luis Felipe Hinojosa, Universidad de Chile & Instituto de Ecología y Biodiversidad
Fernanda Pérez, Pontificia Universidad Católica de Chile & Instituto de Eocología y Biodiversidad
Aurora Gaxiola, Instituto de Ecología y Biodiversidad
Francisca Campano, Universidad de Chile & Instituto de Ecología y Biodiversidad
Sarah Richardson, Landcare Research
Phylogenetical signal leaf morphology and other leaf traits has been detected in several studies, however, in most of cases signal has been low. Evolutionary models, such as stabilizing selection can lead to lo phylogenetic signal. This means that on a single optimum pulls all species back towards a central point, erasing the signal of their prior history, and thus reduce phylogenetic signal. Whether leaf traits are subjected to stabilizing selection or not is today an open question that remains unexplored. Comparing modern and fossil leaves from a specific group may shed light on this question. Nothofagus has been regarded as a key group in southern biogeography it has been a dominant tree in rainforest communities through a long period of time and modern counterparts can be found for some of these fossil communities. Furthermore, Nothofagus species have tracked major shifts in climate and vegetation through the last 80 million years. Therefore, Nothofagus provides an excellent group to test whether leaf traits have been subject to stabilizing selection. In this work, we show a climate reconstruction using the profile niche occupancy obtained from modern locality records of 27 living species along their all modern range distribution, to ask if climate tolerance in Nothofagus evidence (or not) niche conservatism along their phylogeny.
Finally we compare our reconstructions with morphology data in order to give insights about the (possible) mismatch between modern and past climate occupancy in this Gondwanic taxa.
Fondecyt 1120215, IEB PO5-002, PFB- 23
Communicating to public audiences about climate impacts on wildfire, tree mortality, and bark beetle outbreaks in the U.S. Rocky Mountains
Professor Thomas Veblen, Ph.D., Geology Dept., Univ. of Colorado at Boulder
Drawing on personal experince commnciaitng his research to the public, this presentation will discuss the challenges, successes, and failures of communicating climate impacts on wildfires and bark beetles to non-specialist audiences. The research and communciation experiences are centered primarily in the Western United States.
Compensation in pollination systems in New Zealand: bats, rats and bumblebees
David Pattemore, Plant and Food Research
The loss or decline of many endemic vertebrate species (birds, bats and lizards) across large areas of the main islands of New Zealand has led to significant changes in the flower visiting fauna of a wide range of native plants. The loss of these pollinators has been associated with increased pollen limitation, but also presents an opportunity for other flower visiting species to utilise the floral resources and pollinate the flower. This process of compensation could help to maintain pollination as a critical ecosystem function in the face of species extinctions. I will present evidence that novel birds and rats now play an important role in pollination in New Zealand, and discuss why insects – both native and exotic – may be limited in their ability to compensate using the example of bumblebees. This concept of compensation has important implications not just for plant conservation but also for pollination of crop species.
Concordant geographic patterns of climate/morphology/ genotype for Embothrium coccineum, revealed by Multivariate Anisotropic Autocorrelation Analysis
Smouse PE, Rutgers University
Campagne P, Rutgers University
Souto C, Universidad Nacional del Comahue, AR
We examined geographic patterns of climatic, morphological and genetic affinity among 34 populations of Embothrium coccineum, which occupies a 20-degree latitudinal gradient, and spans the crest of the Andes. We developed multivariate anisotropic autocorrelation (MAAC) methods and used them to characterize and compare patterns of morphologic, genetic and climatic divergence among localities. Autocorrelation pattern can be described by an ellipse of eccentricity e=sqrt[(V1 - V2)/V1], where V1 and V2 are the portions of variance accounted for by major and minor geographic axes. V1 + V2 = VT is the total climatic/morphologic/genotypic variation among localities. MAAC analysis shows that e(clim) = 0.40, e(morph) = 0.39, and
e(geno) = 0.42. The major axes run along the Andes, and the minor axes across the cordillera. Climatic and morphologic affinity decreases more rapidly along the major axes than along
the minor axes. Genetic autocorrelation shows the same trends, but the affinity decay patterns are more subtle. Resolving whether morphological and/or genetic patterns represent adaptive radiation or reproductive isolation over this vast geographic range will require experimental work, and the resolution may differ for the two, but it is obvious from our results that both morphology and genotype have major axes of
variation that run latitudinally along the Andes, with secondary longitudinal axes across them.
Consequences of climate change on herpetofauna: limits to ecological inference based on physiological data
Carlos A. Navas, Universidade de São Paulo
Understanding the mechanisms and processes affecting biodiversity patterns is a main current topic in biology. Within this context, anuran amphibians have become a global example of changed biodiversity because patterns of extinctions and declines are unambiguous and ubiquitous. The causes of these declines are multidimensional, and climate change is one among several putative factors, acting either directly or in synergism with other variables. The path to elucidate this complex network of interactions has received contributions from physiological ecology, mainly as a discipline favoring inference about species responses based on individual capacities for adjustment. However, inferring ecology from physiology requires care from at least four points of view: 1) behavior may buffer exposure to environmental conditions, thus affecting the expectation of species-climate equilibrium; 2) The scale at which climatic data-bases are available and the scales at which climate matters for individual animals are still very different; 3) Physiological constraints involve more than acute tolerances, and adjustments may have ecological and energetic costs at longer time-frames; 4) Ecological inference based on tolerances to physical variables requires considering field and experimental rates of change. This is so because experiments exposing individual animals to a given rate and scope of physical change constrain physiological adjustment to the processes that are possible at that temporal course. In this talk I illustrate these four issues offering when possible examples from amphibians and reptiles from different South American biomes.
Conservation planning in a changing landscape – New Zealand’s indigenous grasslands
Emily Weeks, Landcare Research
S. Walker, Landcare Research
J. Overton, Landcare Research
To be effective, conservation planning needs to better anticipate the rates and patterns of dynamic threats to biodiversity, such as rapidly use trends. This is a pressing need in temperate grasslands internationally,
and New Zealand’s indigenous grasslands are a good example. Although the area of formally protected temperate grasslands in New Zealand has increased in recent decades, low to mid-altitude systems continue to be poorly protected and land use intensification has accelerated in recent years. Poor understanding and prediction of
the drivers and patterns of change has made it difficult to assess the relative vulnerability of areas of remaining indigenous grassland habitat, and identify those in most immediate need of protection. Here we use quantitative spatial models to assess and predict the vulnerability of New Zealand’s remaining indigenous grassland habitat to land use intensification in for the first time. Our models are based on our new mapping and measurement of past and current land use in relation to patterns of climate, topography, soils, and proximity to infrastructure (i.e. roads) or existing development. Overall, areas most vulnerable to land-use intensification are located at moderate to high elevations with low slopes that have previously been classified as more suitable for low productivity extensive grazing, but we also found important regional variations. We show that the significance of the remaining biodiversity of the most vulnerable grasslands is recognized by other New Zealand conservation planning tools, but they have not been targeted for conservation in recent land reforms.
Conservation, growth, and demography of Azorella compacta in Parque Nacional Lauca, Chile
Catherine Kleier, Regis University
Will Stenzel, State of Colorado Attorney General Office
Llareta (Azorella compacta: Apiaceae), a giant tropical alpine cushion plant, grows in the alpine desert, puna (altiplano), of Parque Nacional Lauca, Chile. Mining and degazettement of this park threatens llareta habitat. Additionally, its range and distribution, particularly at its highest altitudes (5,250m) and germination rates remain poorly understood. We measured all llareta within 30 different 100 meter transects around the park and determined growth rate using previously marked plants. Llareta is only harvested in the dry season; thus, we saw no active harvesting, though there was some evidence of previous harvesting. We reevaluated 9 plants that were permanently tagged in 1999 to determine llareta growth rate to be 1.1 mm per year, but if calculated for surface area (length x width), it is 26.44 cm2 per year. We measured 406 plants, and on average, 100 meter transects contained about 13 ± 3 plants. Sizes of plants ranged from 1 cm2 up to 515,025 cm2 for a plant 545 x 945 cm. We found no correlation with llareta abundance and elevation via simple linear regression (F = 2.240, p = 0.136), though mean area of all plants in the transect did increase with elevation (F = 9.582, p =0.002). Young size classes (< 20 cm diam.) were most abundant and older size classes were evenly distributed. Our work indicates that conservation efforts with llareta are working.
Continent-wide changes of plant species richness and a thermophilisation of alpine vegetation: recent GLORIA results
Michael Gottfried, University of Vienna
Harald Pauli, Austrian Academy of Sciences
Christian Klettner, Austrian Academy of Sciences
Sonya Laimer, University of Vienna
Georg Grabherr, Austrian Academy of Sciences
High mountain plants and vegetation are excellent indicators of climate change impacts due to two reasons: their distribution patterns within a mountain system are sharply determined by temperature and precipitation, and the world’s high mountains are hotspots of biodiversity and endemism, due to their nature as islands within mainlands. GLORIA – “The Global Observation Research Initiative in Alpine Environments” is dedicated to monitor climate change effects on mountain biota and has a worldwide coverage of currently 81 active study sites, with 31 more in planning. Recent analyses of a European continental-scale dataset unveiled the following effects after a seven years’ period: Species have moved upslope on average. While these shifts lead to increased species richness of summit floras in boreal-temperate mountain regions, the opposite happened in Mediterranean mountain regions. This may be explained by decreasing water availability in the European south falling below critical thresholds. Secondly, warm-adapted species increased in presence and cover to the cost of more cold-adapted ones. This thermophilisation effect is significant on the European scale and its magnitude, varying between mountain systems, is related to regional patterns of climate warming.
Contracting Tasmanian montane grasslands within forests matrix is consistent with cessation of Aboriginal fire management
David Bowman, University of Tasmania
Sam Wood, University of Tasmania
Dominic Neyland, Gregor Sanders
Gregor Sanders, University of Melbourne
Lynda Prior, Gregor Sanders
The persistence of treeless grasslands and sedgelands within a matrix of eucalypt and rainforest vegetation in the montane plateaus of northern Tasmania has long puzzled ecologists. We provide a new historical perspective of the dynamics of the vegetation mosaics of Surrey Hills and Paradise Plains in northwest and northeast Tasmania respectively, and used vegetation surveys and soil sampling to explore the role of vegetation and soils on these dynamics. Sequences of historical maps (1832 and 1903) and aerial photography showed that many treeless patches have persisted in the landscape since European settlement and that forests have rapidly expanded into the treeless patches since the early 1950s. Stand structure and floristic data described an expanding forest dominated by Leptospermum which is consistent with vegetation succession models for the region. Given that existing vegetation boundaries in northern Tasmania do not coincide with soil nutrient gradients, we suggest that treeless vegetation was maintained by Aboriginal landscape burning and that the recent contraction of treeless vegetation is related to the breakdown of these fire regimes following European settlement. The observed rates of forest expansion could result in a substantial loss of these grasslands if sustained through this century and therefore our work supports the continuation of prescribed burning to maintain this high conservation value ecosystem.
Contrasting patterns of soil N and P limitation in early stages of glacial chronosequences in Chile and New Zealand
Cecilia Perez, Institute of Ecology and Biodiversity
Juan Carlos Aravena, Quaternary Studies Center
Wladimir Silva, Institute of Ecology and Biodiversity
Aurora Gaxiola, Institute of Ecology and Biodiversity
Juan Armesto, Institute of Ecology and Biodiversity
Roger Parfitt, Landcare Research
During the progressive phase of ecosystem development increments in productivity and species richness and concomitant increases in soil carbon, nitrogen and organic phosphorus occur. Reductions in total P by weathering and losses from apatite increase soil P- limitations, whereas increases in soil N reduce N-limitation with time, as well as N-fixation rates. However, soil geology and biogeography could modify the strength or direction of these predictions as species could use soil substrates and available nutrients differently. Considering geological and biogeographical differences in glacial chronosequences between Chile and NZ, we contrasted patterns of ecosystem development and nutrient limitation in early stages of soil chronosequences. Results show a power increase in species basal area and saturation in species richness. Although soil N-content increased, C:N values also increased in soil and leaves along stages of the chronosequence. In contrast, soil total P was low and values remained similar along early stages of the chronosequence; soil C:P and N:P increased, however N:P in leaves remained relatively stable with values generally above 12.5, thus suggesting constant P limitation almost irrespective of soil age in this chronosequence. Another contrasting result was that N fixation, in the symbiotic autotrophic green layer of the forest floor, decreased, whereas heterotrophic N-fixation increased. We conclude that sites with P-poor substrates, N and P co-limit plant growth in early stages of chronosequences, however, nutrient use efficient species and the presence of N-fixers allow higher plant biomass and tree basal area than expected from previous studies.
Contrasting spatial and temporal partitioning of humid forest landscapes in Chile and New Zealand
Aurora Gaxiola, Institute of Ecology and Biodiversity & Pontificia Universidad Católica, Chile
Christopher H. Lusk, The University of Waikato, NZ
Peter J. Bellingham, Landcare Research, Lincoln, NZ
Chile and New Zealand can be seen as parallel experiments in temperate forest dynamics; the two regions share many plant clades and a strong influence of recent seismic and volcanic activity, but differ in historical biogeography, geomorphology and soil conditions. Here we compare the ecological roles of Nothofagus and conifers in temperate forests in the two countries. In Chile, the genus Nothofagus is present in nearly all humid forest types, typically forming pioneer stands after coarse-scale disturbance. Nothofagus spp. can persist as ~stable canopy dominants in cool-temperate forest, often coexisting with conifers. In Chilean warm-temperate forests, on the other hand, where shade-tolerant broadleaved trees are abundant, there is usually little recruitment of Nothofagus in old stands, and conifers are scarce except on poorly-drained or shallow soils. In New Zealand, landscape partitioning between Nothofagus and other tree species tends to be spatial rather than temporal. Nothofagus is scarce in New Zealand warm-temperate forests, largely confined to infertile ridges, and rarely pioneering on productive sites the way it does in Chile. As in Chile, Nothofagus typically dominates New Zealand cool-temperate forests, often in persistent mixtures with conifers. Conifers are more widespread and more abundant in New Zealand forests than in Chile, possibly reflecting differences in soil fertility. However, strongly discontinuous age-structures of many conifer species suggest a degree of dependence on infrequent large disturbance events; the precise mechanisms involved remain poorly-understood. Spatial and temporal partitioning of landscapes between conifers, Nothofagus and other broadleaved species thus differ significantly between the two countries.
Contributions to biodiversity within a catchment: The importance of interdrainage connectivity
Cecilia Carrea, University of Tasmania, Hobart, Australia.
Leigh Valentine Anderson, University of Otago, Dunedin, New Zealand.
Dave Craw, University of Otago, Dunedin, New Zealand.
Jonathan M. Waters, University of Otago, Dunedin, New Zealand.
Christopher P. Burridge, University of Tasmania, Hobart, Australia.
Freshwater biodiversity within a catchment is measured in terms of the number and distribution of species. These can be influenced via in situ speciation, movement of lineages within the catchment, or colonization by novel lineages from adjacent catchments following changes in the drainage geometry or during episodic tributary connections. While intercatchment movement is being increasingly reported by genetic studies of obligate freshwater taxa, their frequency and hence likely contribution to catchment biodiversity are largely unknown. In New Zealand, members of the Galaxias vulgaris complex of obligate freshwater fishes exhibit a biogeographic division between the Clutha and Southland region drainages. However, as a product of well-documented river capture events, the fish fauna of two Clutha tributaries have genetic affinities with Southland catchments, which has increased the biodiversity of the Clutha and influenced the distribution of species within it. In this study, we used a phylogeographic approach to identify the genetic affinities of a population of ‘roundhead’ galaxiids found in the lower Clutha system. All samples were genetically attributable to G. gollumoides, and reflect a third independent Clutha colonisation by this otherwise Southland species, rather than movement within Clutha by the lineages that colonised previously. Divergence time estimates implicate headwater connections across low divides between catchments, rather than possible glacially-induced coastal connections. Our results highlight that interdrainage connectivity provides opportunity to increase not only the diversity of species within a catchment, but also the number of lineages within species and the locations they occupy within the catchment.
Cutting up the high country: the social construction of tenure review and ecological sustainability
Jean McFarlane, Lincoln University
Ken Hughey, Lincoln University
Roy Montgomery, Lincoln University
Tenure review of the Crown pastoral leases and licences, in the South Island’s high country tussock grasslands, primarily involves a division of land between production and conservation with freehold and Crown ownership respectively. The Crown Pastoral Land Act 1998 legislates for tenure review and explicitly incorporates ecosystem ecology in the primary guiding objective for this process. Section 24(a)(i) directs that tenure review is ‘to promote the management of reviewable land in a way that is ecologically sustainable’. The implementation of 24(a)(i) was investigated using an interdisciplinary qualitative research approach underpinned by social construction theory. Ecological sustainability is an environmental bottom line approach and the explicit link to ‘management’ was interpreted as providing for ecosystem management, which mandates scientific monitoring of ecosystem function in association with adaptive management of land use and incorporates open consultation with stakeholders and transparency of process and information. Despite the high country tussock grasslands having been socially constructed in declensionist ecological terms from the beginning of European pastoralism, and the congruence of these concepts for the on-going management of these lands, section 24(a)(i) has only been implemented in a most superficial way. It was found that by socially constructing three stakeholders as ‘official’, Land Information New Zealand restricted effective input to themselves, the runholders and the Department of Conservation, and limited the input of the other stakeholders, i.e., the ENGOs, Fish and Game, Ngai Tahu and science.
Deceptive uniformity and the WWD connection: Phylogeographic diversity among intertidal bed-forming mussels in South America (Brachidontes, Mytilidae)
Trovant B, Centro Nacional Patagónico (CONICET)
Orensanz JM, Centro Nacional Patagónico (CONICET)
Basso NG, Centro Nacional Patagónico (CONICET)
Ruzzante DE, Department of Biology, Dalhousie University
Small mussels (Brachidontes s.l.) dominate the physiognomy of mid-intertidal communities along the temperate coasts of South America. Nominal species are difficult to discriminate due to high phenotypic variability. Variation at mitochondrial and nuclear genes (COI, 28S, ITS1) reveal that five species occur in the region: B. darwinianus, B. ‘solisianus’, B. rodriguezii, B. granulatus and ‘B’. purpuratus. Two warm-temperate species found in Uruguay and Brazil (B. darwinianus, estuarine, B. ‘solisianus’, marine) are phylogenetically related to the ‘B. exustus complex’ from the Caribbean providing an example of an antitropical distribution for the clade. Brachidontes rodriguezii, a warm-temperate species (S Brazil to N Argentina), is related to local fossil forms from the Late Miocene, indicating local roots in an ancient warm-temperate biota. The southernmost species, ‘Brachidontes’ (=Perumytilus) purpuratus, the only one in the genus occurring in cold-temperate waters is closely related to ‘B’. (=Austromytilus) rostratus from Australia and species of Mytilisepta (currently in Septiferinae). ‘Brachidontes’ purpuratus is the only species in the genus spreading over two warm and cold temperate regions. Preliminary evidence indicates that it may consist of at least two genetically distinct, phenotypically cryptic forms. Low genetic differentiation in the SW Atlantic and absence of fossils beyond the late Pleistocene suggest a post-LGM expansion originating in populations from the SE Pacific. Despite their apparent uniformity, Brachidontes (s.l.) dominated communities from South America are assembled with components of heterogeneous origins.
Demography of Myrcianthes coquimbensis: a critically endangered shrub of the Atacama Desert
Andrea P. Loayza, Universidad de La Serena, Instituto de Ecología y Biodiversidad de Chile
Danny E. Carvajal, Universidad de La Serena, Instituto de Ecología y Biodiversidad de Chile
Patricio García-Guzmán, Universidad de La Serena, Instituto de Ecología y Biodiversidad de Chile
Francisco A. Squeo, Universidad de La Serena, Instituto de Ecología y Biodiversidad de Chile
Demographic modeling is a powerful tool to study plant population dynamics because it allows researchers and managers to determine whether rare populations are declining, increasing or stable, as well as the evaluation of the relative contributions of the demographic processes occurring in different life cycle stages. Here, we used matrix population models to examine the demography of Myrcianthes coquimbensis, an endemic and threatened shrub of the Atacama Desert of Northern Chile. To study population dynamics, fecundity, growth, and survival were estimated by following the fate of approximately 1200 plants marked across its distribution range. Additionally, we conducted seed predation and germination field experiments to assess recruitment probabilities. We constructed two annual stage-based matrices and a mean transition matrix to examine demographic trends, and conducted prospective time-invariant analyses to calculate population growth rate and elasticities. Overall, M. coquimbensis showed a slightly decreasing population growth rate. Once established, there is little adult mortality, however, recruitment rates are extremely low as between 70 and 100% of the seeds are depredated. Moreover, there is little to no seedling emergence, and very low probabilities of survival once a seedling emerges. Prospective analyses showed that reproductive adults contribute most to population growth. These results indicate that the most promising management strategy to conserve this species is to give special care to reproductive adults.
Detailed Climatic, Fire and Vegetation Variability during the last 18,000 years at Lago Lepué (42° S-72° W), Isla Grande de Chiloé, Chile
Oscar H. Pesce G., Dept. de Ciencias Ecológicas e Instituto de Ecología y Biodiversidad, Universidad de Chile
Patricio I. Moreno, Dept. de Ciencias Ecológicas e Instituto de Ecología y Biodiversidad, Universidad de Chile
Detailed pollen and charcoal records from Lago Lepué, a small-closed basin lake located in Isla Grande de Chiloé, show major changes in vegetation and paleofires over the last 18,000 years. Currently, this lake is located in an area influenced by the southern westerly winds (SWW), determining the presence of temperate rainforests dependent on rainfall carried by these winds. At multi-millennial timescales we distinguish: (1) between 11.7-17.5 ka (ka=1000 years before present) dominance of North Patagonian rainforests under colder and wetter conditions than present day, (2) between 7.8-11.7 ka, a decline in North Patagonian rainforest taxa and dominance of Valdivian rainforest taxa under warmer and drier conditions than present, (3) a change in the opposite direction between 2.5-7.8 ka, and (4) high variability in vegetation and climate regimes since 2.5 ka. We detect peaks of fire activity between 8.5-12 and 1-2.4 ka, which were contemporaneous with conspicuous increases in Weinmannia trichosperma, a tree species favored by disturbance. Lake level changes are evidenced by variations in the aquatic plant Isoetes: increase in percentage of this plant involving lake level decrease and vice versa. The occurrence of paleo-fires happens synchronously with times of low humidity, low lake level and high temperature. Our results strongly suggest changes in the SWW at millennial and submillenial timescales involving abrupt variation in climate causing rapid and sharp changes in vegetation ensemble and in fire occurrence.
Determining the drivers of plant rarity: a mechanistic approach
Debra M. Wotton, Landcare Research
Richard P. Duncan, Lincoln University
William G. Lee, Landcare Research
Ian A. Dickie, Landcare Research
Globally, many plant species have small, declining populations that are threatened with extinction and will require management if they are to persist. More than a third of New Zealand’s vascular plant species are considered rare. The mechanisms that influence the abundance and distribution of plant populations are poorly understood and to date have mostly been derived from comparative approaches. Our research aims to understand the underlying causes of rarity in native New Zealand plant species using a mechanistic approach.
We tested three hypotheses: that, relative to common species, the recruitment of rare plant species is (1) primarily limited by seed availability due to seed production or dispersal constraints, (2) constrained primarily by the availability of ‘safe sites’ suitable for seedling establishment, and (3) that rare species suffer from stronger negative soil-feedbacks beneath parent plants than away, relative to common species, and consequently are more dependent on seed dispersal. We conducted field and glasshouse experiments using six pairs of co-occurring rare and common congeneric plant species at four sites in Canterbury and Otago, South Island. We will present research findings and discuss the implications for conservation management of rare and threatened plants.
Developing management strategies using an expert workshop approach for Tasmanian lowland native grasslands under climate change
Louise Gilfedder, Department of Primary Industries, Parks, Water & Environment
Tasmanian Institute of Agriculture, Hobart, Tasmania, Australia., Kerry Bridle
Natural England, London, United Kingdom, Nicholas Macgregor
Tasmania holds some of Australia’s most iconic and valued ecosystems and landscapes, and has an outstanding record of Protected Area establishment with 44% of public land in reserves and 1% of private land under conservation easement or agreements. However some ecosystems such as temperate indigenous grasslands exist mainly on private land, adding complexity to planning future conservation and adaptation options. Tasmanian agricultural enterprises are well placed to take advantage of increased temperatures, with government support in the form of irrigation development creating water surety. The resulting programme of agricultural intensification will potentially place additional pressure on natural resources and important grassland values. To identify options for allowing nature conservation to adapt to a changing climate, we held a structured expert workshop bringing together Tasmanian climate change researchers and policy makers working in the conservation management of terrestrial and freshwater systems. The workshop explored climate impacts of greatest conservation concern, the challenges of setting conservation goals in a changing climate, possible management actions required and knowledge gaps. The barriers and opportunities affecting implementation of adaptation in three administrative regions, and the necessary policies that might be required, were then discussed. This enabled us to identify similarities and differences in the approach to adaptation that might need to be taken in different ecosystems and regions. We discuss our findings with particular reference to identifying specific adaptation guidelines for the conservation and sustainable management of the nationally threatened lowland temperate grasslands.
Did megafaunal extinction or climate change cause increase in erosion post-40 ka BP in Tasmania? - The evidence from studies in the forest estate
McIntosh P D, Forest Practices Authority, Hobart
There is strong evidence that the Tasmanian megafauna became extinct at about 40 ka BP, at the same time as the oldest dated human habitation in the state. Evidence from Australian mainland sites indicates that ecological change followed megafaunal extinction rather than preceding it. The erosion record in Tasmania shows a large increase in the number of fluvial, colluvial and aeolian deposits after 40 ka BP, and especially after 35 ka BP. Two possible reasons to account for these observations are: (1) climate became more droughty and possibly more windy after 40 ka BP; or (2) extinction of the megafauna caused shrublands to flourish and fires were more intense after 40 ka BP, inducing massive erosion.
The semiarid zone in Tasmania certainly had much greater extent in the Last Glacial, and included areas that now have ‘wet’ eucalypt forest and rainforest; evidence from several sites indicates landscape instability and weak vegetation cover down to present-day sea level; and wind speeds were high enough to move 600 mm diameter Pecten valves in aeolian sands dated 30 ka BP south of Hobart.
The lack of a definitive Last Glacial pollen record from eastern Tasmania (likely to be more sensitive to environmental change than wetter sites in the west) makes it difficult to judge which hypothesis best explains the data. Obtaining a deep core and pollen record from Last Glacial peaty deposits in eastern Tasmania should be a priority for sorting out influences on the Last Glacial ecology of the state.
Discovering the New Zealand amber forest biota
Uwe Kaulfuss, Department of Geology, University of Otago, New Zealand
Daphne E. Lee, Department of Geology, University of Otago, New Zealand
Jennifer M. Bannister, Department of Botany, University of Otago, New Zealand
Vincent Perrichot, Géosciences & Observatoire des Sciences de l’Univers de Rennes, Université Rennes, France
Alexander R. Schmidt, Courant Research Centre Geobiology, Georg–August–Universität Göttingen, Germany
Amber is nearly ubiquitous in lignites from Otago and Southland and elsewhere throughout New Zealand; however, until recently no paleontological work has been conducted on amber–preserved fossils. Until now, no animal inclusions and only a few floral remains have been recognised. In an ongoing study, we have examined amber from several Cretaceous to Miocene sites in southern New Zealand. At sites such as Newvale and Cosy Dell (Oligocene), and Roxburgh and Idaburn (Miocene), amber occurs in situ as discrete blocks, millimetre–sized drops, sometimes closely associated with wood, presumably of the resin producing trees, or as tiny resin plugs on leaf macrofossils such as Halocarpus. Reworked amber is present in non–carbonaceous shallow marine and estuarine sediments at several Cenozoic sites in southern New Zealand. Our preliminary study has revealed a range of well–preserved fungi, plant and animal inclusions including (1), pieces of araucariacean wood, (2), fungal remains such as two-celled ascospores, numerous septate conidia, mycelia of sooty moulds (Capnodioales) as well as ascomycete fruiting bodies which possess exceptionally long setae on their surface, (3), numerous sheathed prokaryotic filaments, (4), arachnids such as mites, a possible tick and two spiders, and (5), insects including dipterans, spring tails (Collembola), an ant and lepidopterous wing scales. These finds represent groups with an otherwise poor fossil record in the Southern Hemisphere and, for the first time, attest to the quality of New Zealand amber inclusions and their potential for reconstructing terrestrial forest and forest–floor ecosystems in the Cretaceous and Cenozoic.
Dispersal and the comparative spatial ecology of four large-seeded species in the Jarrah forests of southwestern Australia
Andrew P. Nield , Murdoch University
George L. W. Perry , University of Auckland
Neal J. Enright , Murdoch University
Philip G Ladd, Murdoch University
There is growing interest by ecologists in the application of spatial statistics to look at 'why space matters', in an effort to link spatial point patterns to complex processes. The spatial arrangement of plants can reveal a great deal about important biotic and abiotic influences on plant demography. Dispersal is a key agent driving spatial point patterns at multiple scales, with disperser decline likely to have significant negative demographic consequences for those species with highly specific dispersal mutualisms. In the southwestern Australian Jarrah (Eucalyptus marginata) forests the sole extant disperser of large-seeded species, the emu (Dromaius novaehollandiae), is in decline. We examined the effect of the loss of this primary dispersal agent on the spatial ecology of four large-seeded species with different seeder/resprouter life histories within contrasting impacted vs. in tact sites (low/high emu abundance). We applied increasingly complex spatial models to the data and assessed departure of our observed pattern data from complete spatial randomness (CSR - homogenous Poisson process), inhomogeneous Poisson processes, and homogeneous and heterogeneous Cluster models. Traditional summary spatial statistics were also applied. At sites with low emu abundance, seeder species were particularly susceptible to aggregation at small spatial scales, though this effect was not uniform. Spatial aggregation will likely lead to negative demographic consequences as species struggle amongst conspecifics.
Dispersal syndromes in the temperate forests of Chile and New Zealand: importance of current climate and past constraints
Fiona Thomson, Landcare Research
Fernanda Pérez, Instituto de Ecología y Biodiversidad; P. Universidad Católica de Chile
Felipe Hinojosa, Instituot de Ecología y Biodiversidad; Universidad de Chile
Fleshy-fruited plant species are common in tropical forests, with the proportion of fleshy-fruited species often increasing with increasing rainfall and temperature. In the temperate forests of New Zealand and Chile the proportions of fleshy fruited species are relatively high. For Chile this pattern is thought to be a historical legacy of a past tropical climate, this also may be the case for New Zealand. To test whether temperature or rainfall are influencing fleshy-fruited species we examined the proportion of fleshy-fruited species, we look decreases with latitude and increases with rainfall and temperature in both Chile and NZ. We also examine the role that phylogeny plays on the proportion of fleshy-fruited species in both countries. Finally, we explore the temporal variation in the frequency of fleshy fruited species, comparing paleofloras from the neogene and paleogene to the present day flora.
Divergence of island biotas when they were not always islands
Chris Burridge, University of Tasmania
Danielle Nankervis, University of Tasmania
Lindi Olivier, University of Adelaide
Jessica Wadley, University of Adelaide
Bill Brown, DPIPWE, Tasmania
Jeremy Austin, University of Adelaide
Continental shelf islands are islands that possessed terrestrial connections to other landmasses via exposed continental shelf during low sea stands. These islands often contain lineages that are related but distinct from those on the adjacent mainland, and their divergence is usually assumed to reflect isolation initiated by the post LGM marine transgression. However, a range of alternate divergence scenarios exists. Divergence may have been initiated by an earlier marine transgression and was retained through subsequent glacial periods of terrestrial connection, or may have been dissociated from sea level changes, involving marine dispersal. Here we test these alternate scenarios for a species that exhibits morphologically distinguishable lineages between Tasmania and the Australian mainland, but also has marine dispersal potential—the wedge-tailed eagle Aquila audax. Genetic variation was surveyed at 20 microsatellite loci and in mitochondrial DNA, from 148 Tasmanian and 48 mainland individuals. The populations differed significantly in allele frequencies, and gene flow subsequent to the initiation of their divergence was rejected. While this is consistent with marine transgression initiating lineage divergence, estimates of age of this divergence substantially post-dated the most recent marine transgression, rejecting this mechanism. Instead, the data are consistent with a small number of mainland individuals colonising Tasmania by marine dispersal, and subsequent isolation. This study highlights that divergence of continental shelf island biotas from those of the adjacent mainland do not necessarily follow the paradigm of initiation by marine transgression, and have bearing on the conservation status applied to putatively ‘long-isolated’ lineages on such islands.
Diversification of halictine bees in the south western Pacific: insights into a recent radiation
Scott VC Groom, Flinders University
Mark I Stevens, South Australian Museum
Michael P Schwarz, Flinders University
Although bees form a key pollinator suite for flowering plants, very few studies have examined the evolutionary radiation of non-domesticated bees over human time-scales. This is surprising given the importance of bees for crop pollination and the effect of humans in transforming ecosystems via agriculture. In the south western Pacific (SWP), where the recorded bee fauna appears depauperate, their importance as pollinators is not clear. Here we explore the radiation of halictine bees in the neighbouring archipelagos of Vanuatu and Fiji using mtDNA COI sequence data. Both island groups exhibit similar topologies with several ‘deep’ clades whose divergences are close to the crown node, along with highly derived ‘broom’ clades of very high haplotype diversity. Analyses of haplotype lineage accumulation show a steep increase in selectively neutral COI haplotypes corresponding to the emergence of these ‘broom’ clades. We explore three possible scenarios for this dramatic increase: (i) a key change in adaptedness to the environment, (ii) a large-scale extinction event, or (iii) a dramatic increase in suitable habitats leading to rapid population expansion. We argue that Homalictus first colonized the Vanuatu archipelago in the middle Pleistocene, and the rapid accumulation of haplotypes in the hyper-diverse clades occurred in the Holocene, prior to human presence in Melanesia. Our results indicate that bees have not been important pollinators of SWP angiosperm ecosystems until very recent times. Post-Pleistocene climate change and anthropogenic impacts are likely to have greatly transformed pollinator suites from when those ecosystems were first being assembled.
Diversity ‘down under’: molecular phylogenetics and biogeography of the ancient subterranean Australian Parabathynellidae (Syncarida, Crustacea)
Kym Abrams, Australian Centre for Evolutionary Biology and Biodiversity, School of Earth and Environmental Science, The University of Adelaide, SA 5005
Michelle Guzik, Australian Centre for Evolutionary Biology and Biodiversity, School of Earth and Environmental Science, The University of Adelaide, SA 5005
Steve Cooper, Evolutionary Biology Unit, South Australian Museum, North Terrace, Adelaide, SA 5000
Bill Humphreys, Western Australian Museum, 49 Kew Street, Welshpool, WA 6106
Rachael King, South Australian Museum, North Terrace, Adelaide, SA 5000
J-L.Cho , National Institute of Biological Resources Korea, Incheon, 404-170, Korea
Andy Austin, Australian Centre for Evolutionary Biology and Biodiversity, School of Earth and Environmental Science, The University of Adelaide, SA 5005
The putatively ancient subterranean crustacean family Parabathynellidae has been poorly studied, in part because of the problem of obtaining material from difficult to access subterranean aquatic habitats in which they live. Further, the systematics of the group has been complicated by their generally simplified morphology and isolated descriptions of new taxa in the absence of any phylogenetic framework. Here, we use a comprehensive molecular systematics study of Australian Parabathynellidae based on COI and 18S sequence data, to explore their phylogenetic relationships, diversity, some aspects of character evolution, and their biogeographic history within Australia. Our results suggest that genera are largely monophyletic and revealed numerous unknown taxa. They also provide evidence for high levels of endemism in Australia, in addition to uncovering ancient connections among clearly disparate geographic locations. The tendency towards short-range endemism has rendered parabathynellids vulnerable to perturbations of groundwater, which has significant implications for their management. The conservation value of parabathynellids is a high priority not only because of their uniqueness, but also because of their role in biofiltration and as bioindicators of groundwater quality. Our results also emphasize the conservation importance of groundwater habitats.
Do high-elevation populations of the Wellington tree weta (Hemideina crassidens) show metabolic cold adaptation?
Mariana Bulgarella, Massey University
Mary Morgan-Richards, Massey University
Steve A. Trewick, Massey University
Many species are distributed along elevation gradients, with populations living at the upper and lower altitudinal extremes experiencing quite different environmental conditions with respect to local climate. Temperature strongly affects organismal life, impacting on the distribution and abundance of species. Metabolic cold adaptation (MCA) is the phenomenon by which species or populations from high-altitude and latitude show elevated metabolic rates at low temperatures equivalent to those of species from warmer environments at much higher temperatures. These elevated rates are thought to allow animals to meet the increased ATP costs of growth and development necessary for completion of life cycles in the shorter growing season found in cold environments. The MCA hypothesis is controversial but it has been reported to occur at the intraspecific level in several ectotherms. The objective of this study is to compare standard metabolic rates (SMR) and Q10 (the quotient by which the rate of a process increases when the temperature increases by 10°C) among high- and low-elevation populations of the Wellington tree weta (Hemideina crassidens) after acclimation to two different temperatures. We predict that high-elevation populations of tree weta will have higher SMR at lower temperatures to allow for better activity. Preliminary analysis suggests no effect of population or acclimation on SMR and low thermal sensitivity of metabolic rates as determined by low Q10 values. High-elevation tree weta might deal with cold temperatures by reducing sensitivity of the metabolic rate-temperature curve or by some other mechanism.
Does palynology give us any clues to the possible inundation of Zealandia in the Late Oligocene?
D.C. Mildenhall, GNS Science, P.O. Box 30368, Lower Hutt, New Zealand
M.J. Isaac, GNS Science, P.O. Box 30368, Lower Hutt, New Zealand
E.M. Kennedy, GNS Science, P.O. Box 30368, Lower Hutt, New Zealand
D.E. Lee, Department of Geology, University of Otago, PO Box 56, Dunedin, New Zealand
T. Allan, CSIRO Earth Science and Resource Engineering, 11 Julius Avenue, North Ryde, NSW 2113, Australia
Whether or not the continent of Zealandia was inundated in Oligocene time is important for the interpretation of the history of New Zealand’s biota. Fossil pollen grains preserve a record of ancient vegetation. Twenty localities where rocks were deposited close to the suggested time of inundation were selected for palynology studies. Well preserved diverse pollen and spores were recovered in most samples.
The palynofloras represent regional subtropical lowland coastal forest and local swamp and coastal lagoon margin vegetation. Diversity is at least three times that of the modern day, even excluding from consideration the large numbers of undescribed taxa. There are at least eight different gymnosperm pollen types alone, some of which probably represent several individual species.
The palynological results have cast some doubt on the validity and applicability of the previously recognised pollen-based biostratigraphic zones. If the zones are valid then it seems unlikely they can be used to adequately test the inundation hypothesis, because of the comparatively long time period represented by any single zone. A lot can happen in a million years.
The common intercalation of Oligocene–Early Miocene pollen-rich terrestrial sediments and shelly shallow marine facies offers a new approach, for strontium isotope dates on carbonate shells can be used to help establish an absolute age scale for the pollen zones, and to determine the timing of maximum submergence.
Can palynology disprove Oligocene inundation? Probably not – but it does provide support for the view that a stable, well vegetated land mass prevailed.
Does the Messenger Kill the Message: How Climate Change and Scientists Come Across on Television News
Professor Lloyd Spencer Davis, Ph.D., Centre for Science Communication, University of Otago
This presentation will include preliminary findings from research conducted by the University of Otago's Centre for Science Communication as well as a consideration of storytelling as a vehicle for scientists to communicate their science. Professor Davis is the holder of the Stuart Chair in Science Communication as well as the Director of the Centre for Science Communication
at the Unviersity of Otago.
Does winter matter in the mild? Changing winters and Southern Hemisphere insects
Brent J. Sinclair, University of Western Ontario
Temperature is a key determinant of insect performance and distribution, and winter, when insects usually do not breed or feed, can have a strong influence on the success and sustainability of populations. Northern temperate winters can have a huge influence on biology, but the milder climates in the Southern Hemisphere temperate and sub-Antarctic regions might be thought to have less of an influence. I will first compare the nature of winter on each side of the equator, and identify the commonalities and differences. I will survey what is known about the physiological and ecological responses of southern hemisphere insects to winter. Climate change may affect the mean and variance of winter temperatures, as well extreme events and snow cover, and I will discuss the ways in which these sorts of changes can have a profound impact on insect biology.
Ecosystem carbon and grazing reduction on New Zealand montane tussock grasslands
Larry Burrows, Landcare Research
Duane Peltzer, Landcare Research
Ian Lynn, Landcare Research
Richard Clayton, Landcare Research
Ecosystem C sources and sinks in grazed montane tussock grassland systems are of interest due to their effect on national carbon budgets and mitigation potential. There is very little quantitative information on ecosystem C stocks and fluxes in relation to land-use in New Zealand montane tussock grasslands. We describe and quantify the interactions of high country grazing, ecosystem C stocks and sequestration, and estimate the changes in ecosystem C that results from removal of sheep for periods of >3 decades. Plant biomass C and litter C both increased marginally following grazing retirement but we did not detect a change in soil C, or a total ecosystem C change due to the high proportion of the total C in soil. Most variation in ecosystem C and C pools is caused by differences among sites rather than by grazing management. The results support the view that low-intensity grazing of these systems does not affect ecosystem C, unlike intensively managed lowland agricultural lands.
Effect of climate on Australian alpine vegetation using the GLORIA monitoring protocol
Catherine Pickering, Environmental Futures Centre, Griffith University
Ken Green, New South Wales National Parks and Wildlife Service
Susanna Venn, Environmental Futures Centre, Griffith University
Alpine ecosystems are particularly vulnerable to climate change, with reduced snow and warmer climate already resulting in changes in plant composition. Australia is part of the Global Observation Research Initiative in Alpine Environments (GLORIA) network which uses a standardized protocol to monitor changes in plant composition in >110 mountain regions. In the Snowy Mountains in Australia, five alpine summits (1,813 m to 2,114 m) were selected as GLORIA sites. The cover and composition of all vascular plants (years 2004 and 2011) soil temperatures (continuously) and soil nutrients (2004) were assessed at the four cardinal compass bearings on each summit. There was an altitudinal gradient in species richness across summits with shrubs dominating the lowest altitude summit and herbs and graminoids dominating higher summits. Climate variables including the duration of the growing season, thaw date and minimum and maximum soil temperatures explained around 43% of the variation in plant composition in 2004. By 2011, species richness had increased by 6, with 80 taxa recorded in total. However, species turnover was moderate, and not related to altitude, nor variation in climate conditions. When plant functional traits and measures of functional diversity were assessed, the higher altitude summits were dominated by species with higher specific leaf area ratios and large leaves, while lower attitude summits had taller species with higher leaf dry matter content. These findings, in addition to future surveys, will elucidate community assembly processes operating across the gradient of summits in this high-conservation flora.
Effects of landscape alteration on Hymenoptera trophic guilds at several scales of fragmentation in the Chaco forests of Cordoba, Argentina
Mariana Musicante, Universidad Nacional de Chilecito - Instituto Multidisciplinario de Biología Vegetal – CIEC
Marcos Monasterolo, Universidad Nacional de Córdoba - Centro de Investigaciones Entomológicas de Córdoba (CIEC)
Adriana Salvo y Leonardo Galetto, Instituto Multidisciplinario de Biología Vegetal - CONICET
Winter deciduous dry tropical monsoon forests of the Chaco region are being destroyed at an accelerated pace, mainly due to the expansion of soya (200,000 ha/year). This study examines the impact of fragmentation of Chaco Serrano forests in the province of Córdoba, Argentina, on Hymenoptera trophic guilds in 9 forest fragments ranging in size from 0.5 to 10,500 hectares. Four sampling methods were used to detect the occurrence of a great number of species: observations on flowering plants, trap nests, pan traps and sweep nets. Parasitoids presented the highest species richness, while pollinators had the highest abundance, predators occupied an intermediate position, and cleptoparasites had the lowest numbers of species and individuals. Guild species richness varied according to fragment size, site features,distance to other fragments, and matrix (composition and heterogeneity). Although some species are lost with fragmentation, small fragments can maintain high species richness as long as the surrounding matrix provides heterogeneity with adequate food and nesting sites. Conversely, small fragments provide the surrounding matrix (typically soya cultivation and or areas of secondary regrowth) with services inversely proportional to their distance. Thus, even small fragments are essential to maintaining hymenopteran biodiversity and ecosystem services for both cultivated and native plants.
Empirical measures for successful restoration of seabird island ecosystems after invasive mammal eradications
James C. Russell, The University of Auckland
David Towns, Department of Conservation
Chris Jones, Landcare Research
Phil Lyver, Landcare Research
David Wardle, Swedish University of Agricultural Sciences
Christa Mulder, University of Alaska Fairbanks
Peter Bellingham, Landcare Research
Invasive mammalian predators change the way island ecosystems function. On uninvaded islands, ecosystems are often subsidised by marine nutrients imported through seabird activity, which leads to an abundance of litter invertebrates. On invaded islands, seabird effects are greatly reduced, ecosystems have diminished marine subsidy, and there are important new direct and indirect effects on litter invertebrates. If seabirds are able to recolonise when invasive species are removed, traits typical of the subsidised ecosystems should in theory recover. However, the time taken for this recovery, and ways of measuring the associated ecosystem responses, are unknown. We describe measures of ecosystem recovery on Korapuki Island off the coast of north-eastern New Zealand 25 years after the removal of invasive rats and rabbits. Two approaches are outlined. The first approach tests hypotheses about the form of recovery likely for soil chemistry and litter invertebrates based on previous comparisons between islands invaded by seabird predators and those never invaded. The second approach involves the use of quadratic discriminant function analysis (QDFA) to test convergence between Korapuki and uninvaded islands. We found that the relationship between the abundance of selected litter invertebrates and seabird activity was consistent with advanced ecosystem recovery on Korapuki Island. Furthermore, QDFA also indicated that most measures of ecosystem function on Korapuki Island were consistent with uninvaded islands. We conclude that after less than three decades, most sites on Korapuki Island again demonstrate traits typical of seabird driven ecosystems.
Environmental filters in an alpine environment: a test of plant functional traits for understanding mechanisms of change
Susanna Venn, La Trobe University
Alan Mark, Otago University
Annika Korsten, Otago University
John Morgan, La Trobe University
In plant community assembly theory, environmental filters are the abiotic conditions and resources that exclude species with unviable physiological limitations (defined by their functional traits) from entering or persisting in a community. Measures of functional trait diversity can be used to determine community responses to current and altered environmental filters. In alpine areas, snowmelt is a strong environmental filter. The Old Man Range snowfence, erected in 1959 in alpine tundra, Central Otago, provides an opportunity to test the effect of a changed environmental filter (snowmelt) on local species/trait (re)distribution.
The snowfence profoundly affected the lee side environment, creating a snowdrift and significantly reducing wind speeds. While change in species composition over time has been well documented, the mechanisms that underpin vegetation change are unclear. Functional traits such as leaf dry-matter content, leaf nitrogen and specific leaf area have all been proposed as important indicators of plant responses to environmental filters, and may be key in understanding the processes that have allowed certain plants to establish, increase, persist or decline at the snowfence site.
We randomly sampled vegetation from three snowmelt zones in the lee of the fence and related leaf traits with species abundance. We then used an index of functional diversity to determine the influence of each trait on vegetation composition within each snowmelt zone. We saw clear differences in species distribution in relation to the snowmelt zones, and demonstrate how plant functional traits can provide a mechanistic understanding of the ways plants respond to altered environmental filters.
ENVIRONMENTAL VARIABILITY AND RESOURCE USE OF AN ANDEAN LAKE INFERRED USING FOSSIL DIATOMS
María Laura Carrevedo Goytía, Department of Ecology, Pontificia Universidad Católica de Chile, Institute of Ecology and Biodiversity (IEB)
Claudio Latorre, Department of Ecology, Pontificia Universidad Católica de Chile. Institute of Ecology and Biodiversity (IEB)-Santiago, Chile. Laboratorio Internacional de Cambio Global (LINCGLOBAL), PUC-CSIC.
Ana Luisa Herrera, Department of Ecology, Pontificia Universidad Católica de Chile
Matías Frugone, Laboratorio Internacional de Cambio Global (LINCGLOBAL), PUC-CSIC. Instituto Pirenaico de Ecología –CSIC Zaragoza, España.
Héctor Orellana, Department of Ecology, Pontificia Universidad Católica de Chile
Blas Valero-Garcés, Laboratorio Internacional de Cambio Global (LINCGLOBAL), PUC-CSIC. 4Instituto Pirenaico de Ecología –CSIC Zaragoza, España.
Laguna del Maule is a volcanic lake (36°S-70°N, 2160m) in the Cordillera de Los Andes, 250 km S of Santiago de Chile, area: 45 km² and maximum depth of 50 m. Salmonids and myriophylum macrophytes are abundant and it has sectors for trekking, mountaineering and off road. In 2011 and 2012 (pioneer surveys) six cores were obtained with a gravity corer (4, 43, 50 and 31m depth), Pb210/Cs137 studies were carried out. Cores were opened, photographed and described sedimentologically. Core LEM11LEMAL-1G-1A (54cm long) showed two volcanic tephras and was volumetrically subsampled every 5cm, aliquots were taken for diatomic analysis, processed according to standard methods, permanent slides were mounted and observed under an optical microscope. We use diatoms as bioproxies to infer past environmental conditions because they are highly sensitive to changes on rate and nutrients supplies and are powerful tools to quantify eutrophication. The first 5cm of the core were studied, understanding that the surface sediments represent an integrated sample from the lake diatoms, both spatially and temporally. 38 genera were identified belonging to Bacillariophyceae and presence/absence analysis of diatoms associations showed high species richness: 70spp and let infer mesotrophic water conditions, because of the presence of Asterionella Formosa and Fragilaria crotonensis (planktonic) to eutrophic: Aulacoseira granulata and Stephanodiscus sp. (planktonic). These results are indicative of strong natural eutrophication events (high levels of phosphorus and nitrogen) in recent times as a result from prolific of spawning salmonids and deep water anoxia with subsequent release of phosphorus from sediments.
Eocene and Oligocene paleogeography between Australia, New Caledonia, and New Zealand
Rupert SUTHERLAND, GNS Science
Francois BACHE, GNS Science
Julien COLLOT, Service Géologique de Nouvelle-Calédonie
Vaughan STAGPOOLE, GNS Science
Pierrick ROUILLARD, Agence de Développement Economique de la Nouvelle-Calédonie
Takehiko HASHIMOTO, Geoscience Australia
Ron HACKNEY, Geoscience Australia
Karen HIGGINS, Geoscience Australia
Nadège ROLLET, Geoscience Australia
The Tasman Frontier region covers c. 3,000,000 sq km of seabed between Australia, New Caledonia and New Zealand. We have compiled and interpreted c. 100,000 line km of existing seismic reflection data. Using seismic stratigraphy tied to Deep Sea Drilling Project (DSDP) wells, we identify a tectonic and stratigraphic event that we refer to as the “Tectonic Event of the Cenozoic Tasman Area” (TECTA). This Middle Eocene to Late Oligocene event involved regional uplift followed by 1–2 km of tectonic subsidence of topographic highs, and >2 km of tectonic subsidence in the New Caledonia Trough. Strata below the TECTA reflector (or seismic unit in some places) are locally folded or reverse faulted. We present seismic-stratigraphic evidence that numerous islands were transiently created by uplift on the Lord Howe Rise during the TECTA event. The precise timing of uplift is poorly constrained. The most simple hypothesis is that uplift was broadly synchronous and sustained for several millions of years. It is a reasonable alternate hypothesis that a wave of uplift propagated from north to south. We suggest that the underlying cause of the TECTA event was initiation of subduction that has since evolved into the Tonga-Kermadec system.
Eocene-Miocene islands of the Zealandia archipelago: evidence from sandstones and limestones
Nick Mortimer, GNS Science
Today the continent of Zealandia is c. 93% submerged. Because New Zealand lacks unambiguous evidence of non-marine strata across the 23-26 Ma (latest Oligocene-earliest Miocene) interval, there has been debate as to whether Zealandia was totally submerged at this time or if there were emergent islands. The mineralogical and geochemical compositions of 21 Eocene, Oligocene and Miocene marine and non-marine sandstones from the Waiau, Te Anau, Murchison and Taranaki basins have specific matches with local basement sources and show little change during this time interval. The sandstones are thus interpreted as immature first-cycle clastic deposits shed directly from land; they are not well mixed and reworked marine shelf deposits as might be expected if there had been total drowning of Zealandia. A compilation of 1300 carbonate analyses of New Zealand Oligocene limestones shows that they have a non-carbonate component that is substantially higher than modern day isolated shelf limestones such as the Bahamas and Maldives. Where petrographic data are available this component is shown to comprise mainly angular grains of land-derived quartz and feldspar. While Zealandia probably was >95% submerged from 23-26 Ma, this study indicates the presence of local island landmasses (sediment sources) that persisted across the Eocene-Miocene interval.
Estimating carbon stocks in Australia’s forests to reduce carbon dioxide emissions and retain biodiversity
Grant Wardell-Johnson, Curtin Institute for Biodiversity & Climate, Curtin University
About half of the world’s forests have been cleared and emissions from clearing of vegetation and soil degradation, contributes the second largest net source of CO2-e to the atmosphere. Avoiding and reducing land carbon emissions is an integral part of a comprehensive approach to climate change. We outline an approach to estimating carbon stocks in forest ecosystems that allows assessment of avoided emissions of CO2-e. We also present an ecological and carbon accounting prognoses under climate change for two old-growth, temperate forests (tall open-forests of south-western Australia and Tasmania). Under climate change the warmer, dryer climate in both areas will decrease carbon stocks directly; and indirectly through changes towards dryer forest types and through positive feedback. Near 2100, climate change is likely to decrease soil organic carbon significantly (i.e. by ~30% for south-western Australia and at least 2% for Tasmania). The emissions from the next 20 years of scheduled logging of old-growth tall open-forests in Tasmania, and conversion to harvesting cycles, would conservatively reach 66 (± 33) Mt-CO2-e. Similar emissions will arise from soil organic carbon in the rainforests of Tasmania due to climate change. Careful management of old-growth forests is required to reduce carbon emissions and changes in biodiversity. This will entail adopting new approaches to conserve old-growth characteristics in forest stands. Providing an alternative to native forest logging and deforestation represents a cost effective approach to reduce greenhouse gas emissions. Management of plantation forestry on long-cleared land, and well-targeted prescribed burning will supplement effective carbon management.
Estimating dispersal transfer costs of the brushtail possum using least-cost modelling
Thomas Etherington, Centre for Biodiversity and Biosecurity, School of Environment, The University of Auckland
The brushtail possum is an endangered species in its endemic Australia and a notorious invasive species within New Zealand. Management of the species in both countries needs to consider dispersal, however many dispersal models base the transfer component of dispersal between geographic locations upon a kernel that is purely a function of distance. This approach ignores any landscape barriers to dispersal that impose transfer costs through factors such as energetic expenditure, behavioural aversion, or mortality risk. We estimated the transfer costs associated with brushtail possum dispersal by quantifying the transfer costs associated with landscape barriers, and by describing the likely transfer costs accumulated by dispersing brushtail possums. Assuming that landscape connectedness between pairs of locations can be represented by the genetic relatedness in possums at those locations, a landscape genetics approach based upon least-cost modelling was used to create a geographic information system cost-surface for the North Island of New Zealand that quantified the transfer costs associated with various landscape barriers. Least-cost paths between the start and end points of dispersal movements from radio-collared brushtail possums from several studies were then used to define a dispersal kernel in terms of accumulated-cost units. By using the cost-surface in combination with the accumulated-cost dispersal kernel, existing dispersal models could be refined to include transfer costs as part of the dispersal process in order to better represent dispersal for management of brushtail possums.
Evidence of a massive shift from C4 to C3 plants and biomass burning AFTER the megafaunal extinction in SE Australia from a deep-sea core record
Patrick De Deckker, Australian National University
Raquel Lopes dos Santos [1st author but not presenter], NIOZ, The Netherlands
Stefan Schouten, NIOZ, The Netherlands
John Magee, Australian National University
A 135,000 year record of environmental change recovered from a deep-sea core offshore the mouth of the River Murray that drains the vast Murray Darling Basin of southeastern Australia provides information of the broad vegetation pattern with respect to the distribution of C3 and C4 plants. Progressive shifts are found throughout the record, but a significant shift is noticeable only after the megafaunal extinction that occurred after the arrival of humans in Australia. This coincided also with evidence of biomass burning. Once the burning ceased, vegetation did recover, but never to the same level as before.
Discussion will address the issue of what caused the massive vegetation shift and the biomass burning in line with sea-surface temperatures obtained from alkenones extracted from the core, and hydrological changes registered in the Willandra Lakes area that lies inside the Murray Darling Basin.
The sediment core benefits from a sound chronological framework based on a stable isotopic record of planktic foraminifers, numerous C14 and several OSL dates.
Evolution of climate niche, functional traits, and freezing resistance in Myrceugenia
Fernanda Pérez, P Universidad Católica de Chile. Instituto de Ecología y Biodiversidad
Luis Felipe Hinojosa, Universidad de Chile. Instituto de Ecología y Biodiversidad
Francisca Campano, Instituto de Ecología y Biodiversidad
Carmen Gloria Ossa, Universidad de Chile
Understanding whether plant species retain ancestral ecological characteristics over evolutionary time scales has become a mayor question in evolutionary biology. In the last years a crescent number of comparative studies have shown that often related plant species tends to grow in similar climate environments, bringing the generalized idea that climate niches and ecological tolerance are conserved within plant lineages. This hypothesis is difficult to reconcile with the equally common finding that many plant species can adapt to local climatic condition. In this work, we quantified the climatic niche of chilean species of the genus Myrceugenia (Myrtaceae), an endemic genus of southern South America. We also measured leaf traits that are generally considered adaptations for cold and frost resistance, including leaf area, leaf mass area, stomata density, and C/N ratio. In addition, we measured foliar freezing resistance in field conditions. Then, we estimated phylogenetic signal on climate niche, leaf traits and freezing resistance using a previously published molecular phylogeny of the genus. Finally, we performed independent contrast analyses between environmental and functional variables. We found that, in general, climate niche is more phylogenetically conserved than leaf traits and freezing resistance. We also found a strong correlation between freezing resistance and leaf mass area. These results show that climatic niche conservatism not necessarily reflect conservation of ecological tolerances.
Evolutionary Assembly of Floras and Vegetation in Saline Landscapes: Southern Hemisphere (Dis)Connections
Ladislav Mucina, Curtin Institute for Biodiversity & Climate, Dept of Environment & Agriculture, Curtin University, GPO Box U1987, Perth WA 6845, Australia
Saline flora and vegetation, usually accompanying the arid biomes or saline coastal habitats, are a result of intriguing evolutionary assembly processes. The paper reviews current status of knowledge of patterns and processes in evolution of plant lineages as well as evolutionary assembly of the saline floras and vegetation in three large geographic arenas – sub-Saharan Africa, Australia and South America at various spatial scales spanning (sub)continents, landscapes, and habitats supporting local halophytic vegetation complexes. Origins and nature of saline habitats in terms of landscape-geological and geomorphologic processes including plate and regional tectonics, marine transgressions and regressions, and changes of course of palaeo-riverine systems. Using data on molecular phylogenies and phylogeography of major halophytic lineages (especially of the family Chenopodiaceae/Amaranthaceae) which typically dominate the saline floras of both continents, I shall attempt to demonstrate how major evolutionary large-scale assembly processes (including migrations and in-situ radiations) might have contributed to generating of diversity patterns along large-scale climatic and small-scale hydro-geologic gradients. Perspectives on the further enquiries into evolutionary assembly of the Southern Hemisphere saline vegetation will be outlined.
Exaptation explains interspecific variation in the flammability of the New Zealand flora
Norman Mason, Landcare Research
Foliar morphological traits linked to plant resource use strategies are key to interspecific variation in flammability. Consequently, adaptations of foliar traits to selective pressures other than fire could drive variation in flammability. The New Zealand flora has evolved without frequent fires and thus provides an excellent opportunity to test whether variation in flammability may be driven by exaptation rather than adaptation to fire. We measured leaf thickness, area and perimeter, dry matter content and flammability of dry leaves for 100 indigenous woody and herbaceous species common in forest and scrubland vegetation of New Zealand. We used phylogenetically independent contrasts (PICs) to test whether relationships between morphology and flammability traits were independent of phylogeny. All significant correlations indicated that flammability increased with increasing ratio of foliar surface area to volume and decreasing tissue density. Almost all of these correlations remained significant in PICs. Our results show that variation in flammability within the New Zealand flora is largely due to variation in traits linked to resource use strategy. These findings emphasize the need for caution when invoking fire as the primary selective force that drives PICs between flammability and other traits.
Fire & resprouting: an evolutionary perspective from Chilean plants
Susana Paula, Universidad Austral de Chile
José Gabriel Segarra-Moragues, Centro de Investigaciones sobre Desertificación-CSIC, Spain
Juli G. Pausas, Centro de Investigaciones sobre Desertificación-CSIC, Spain
Wildfires are a widespread phenomenon in the Earth system and are highly implicated in the global ecosystem functioning. Fire has played a relevant role in shaping plant community structure and landscape in many ecosystems. However, the role of fire in shaping plant traits has been questioned on the basis of the existence of plants equipped with fire-persistence traits in regions without a long fire history, as the sclerophylous vegetation of the Mediterranean-type region of Chile. However, fires may have be frequents during previous geological periods, or species may have been originated in fire-prone areas outside of the current distribution. Here we present preliminary results of the analysis of the evolutionary history of fire-persistence plant traits in native plants of central Chile. Certain traits are older than current Mediterranean conditions. The complex assemblage of biogeographic elements in the Chilean flora contributes to explain the variability in those traits.
Fire, invasion and ragamuffin ecosystems
George Perry, University of Auckland, New Zealand
John Ogden, Great Barrier Island Charitable Trust, New Zealand
Neal Enright, Murdoch University, Australia
Matt McGlone, Landcare Research, New Zealand
Janet Wilmshurst, Landcare Research, New Zealand
Many southern forests are characterised by a humpbacked, rather than increasing, relationship between flammability and vegetation age. Because the early successional stage is vulnerable to fire, if ignitions occur a short interval fire cycle may eventuate, carrying with it a positive feedback in which 'fire begets fire'. The massive transformation of New Zealand's forest landscapes at the time of Māori settlement may have been driven by such feedbacks following the introduction of fire to previously ignition-limited ecosystems. Although the humpbacked relationship is inherent in New Zealand's forests, human actions have stretched this curve. Processes that slow succession (e.g., loss of soils, dispersal failure) mean that longer is spent in more flammable successional stages, stretching the curve on the time axis. Ragamuffin ecosystems comprising early successional native species, such as Leptospermum and Kunzea, alongside pyrophillic exotic species such as Pinus and Hakea are much more flammable than uninvaded communities – the presence of these species stretches the curve on the flammability axis. Whether such ragamuffin communities are quasi-stable or whether they will inevitably move towards either high flammability exotic-dominated communities or lower flammability native forest is unclear. Using a spatial simulation model, grounded in empirical data collected from early successional communities on Great Barrier Island northern NZ, we explore the implications of this rescaling of the flammability-age curve and the ability for the ragamuffin ecosystems widespread in northern NZ to persist in the long-term.
Firescape ecology; how topography determines the distribution of fire and rainforest in the southwest of the Tasmanian Wilderness World Heritage Area.
Sam Wood, University of Tasmania
Sam Wood, University of Tasmania
David Bowman, University of Tasmania
Brett Murphy, University of Tasmania
In the Wilderness World Heritage Area of southwest Tasmania, fire-sensitive rainforests exist as ‘islands’ within a matrix of flammable vegetation communities. Whilst it has long been assumed that the spatial distribution of these rainforests is related to topographic fire refugia, the relationships between fire spread, topography and vegetation has not been tested. We used geospatial statistics to (1) identify the topographic determinants of rainforest distribution on nutrient poor substrates, and (b) identify the vegetation and topographic variables that are important in controlling the spatial pattern of a series of very large fires (>40,000 ha) that were mapped using Landsat Thematic Mapper satellite imagery. We found that rainforest was more likely to be found in valleys and on steep south-facing slopes. Fires typically burned within highly flammable treeless moorlands and stopped on boundaries with less flammable vegetation types such as wet sclerophyll forest and rainforest. Controlling for the effect of vegetation, fires were more likely to burn on flats, ridges and steep north-facing slopes, and least likely to burn in valleys and on steep south-facing slopes. These results suggest an antagonism between fire and rainforest, in which rainforest preferentially occupies parts of the landscape where fire is least likely to burn (i.e. topographic fire refugia).
Floral links between ancient Patagonia and the Northern Hemisphere
Maria A. Gandolfo, Department of Plant Biology, Cornell University
Elizabeth J. Hermsen, Environmental and Plant Biology Department, Ohio University
The study of Cretaceous and Paleogene floras of Patagonia, Argentina, plays a key roll for the interpretation and comprehension of the radiation and dominance of the angiosperms in the Southern Hemisphere, and is fundamental for understanding the development of the extant austral vegetation, especially direction and flow of migration routes and dispersal events. Since the early 1900’s, paleobotanical studies have emphasized taxa that supported the lost connection between South America and Australasia via Antarctica (the Southern Hemisphere Connection) through taxa such as Podocarpaceae, Araucariaceae, Nothofagaceae and Proteaceae. New collections from and studies on Cretaceous and Paleogene paleofloras of Patagonia suggest the appearance of a stronger link with ancient and modern Northern Hemisphere floras than previously expected. In this contribution, we will introduce new findings on the “Northern Hemisphere” components of the Campanian-Maastrichtian La Colonia Formation, the Paleogene Baibian beds and the early Eocene Laguna del Hunco locality. We will discuss taxa that previously were only known to have a Northern Hemisphere macrofossil record until discovered as macrofossils in Patagonia, such as Juglandaceae, Regnellidium, and Potamogetonaceae. While some of these taxa might have been expected to occur in Patagonia given their current cosmopolitan or South American distributions, others are unexpected. The occurrence of these taxa within Patagonian Cretaceous and Paleogene sediments that were only previously known from the Northern Hemisphere fossil record expands their ancient distribution and supports a stronger link between the two hemispheres.
Foliar Physiognomy and Palaeoclimate on a Global Stage: Bringing New Zealand into Line.
Robert A. Spicer, Centre for Earth, Planetary, Space and Astronomical Research, The Open University, Milton Keynes, MK7 6AA, UK and Key State Laboratory for Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, P.R. China
Jian Yang, Key State Laboratory for Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, P.R. China
Teresa. E.V. Spicer, Key State Laboratory for Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, P.R. China
Elizabeth M. Kennedy, GNS Science /Te Pu Ao, PO Box 30 368, Lower Hutt 5040, New Zealand
Nan C. Arens, Department of Geoscience, Hobart and William Smith Colleges, Geneva, NY 14456, USA
David C. Steart, Department of Palaeontology, Natural History Museum, Cromwell Road, London, SW7 5BD, UK
Frédéric M. B. Jacques, Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, Yunnan, P.R. China
Tao Su, Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, Yunnan, P.R. China
Gaurav Srivastava, Birbal Sahni Institute of Palaeobotany, 53 University Road, Lucknow-226007, India
Rakesh Mehrotra, Birbal Sahni Institute of Palaeobotany, 53 University Road, Lucknow-226007, India
Paul J. Valdes, School of Geographical Sciences, University of Bristol, University Road, Bristol, BS8 1SS, UK
The relationship between the proportion of woody dicot taxa bearing toothed leaves and mean annual temperature forms the long-used leaf margin analysis palaeoclimate proxy, but this univariate method displays high regional dependency. Biogeographic history and endemism are the likely cause and this is clearly demonstrated in New Zealand. However, a new compilation of field-collected foliar physiognomic data from 394 globally-distributed vegetation sites shows that when multiple leaf characters are included New Zealand vegetation sites conform to global norms across a range of climate variables. For this new dataset sampling, numerical leaf descriptions and analyses were conducted using standardized protocols (http://clamp.ibcas.ac.cn). Calibration was against worldwide gridded (0.16° lat/long) climate data recorded over a common 30-year interval. Strong correlations between leaf form and temperature-related variables show that plants display a universal relationship with climate independent of biogeographic history. That regional variations seen in univariate analyses disappear when several leaf characters are scored implies numerous compensatory roles for leaf architectural features. However, the relationship between individual leaf characters and climate variables is not globally uniform: in monsoon climates leaves show markedly different physiognomic adaptations to those in more maritime and equable precipitation regimes. This degrades the predictive capability of the multivariate proxy when, as in its present form, predictions are based on regression models between observed climate and vector scores indicative of general trends. To overcome this we have developed a new approach that models climate surfaces in multidimensional physiognomic space. This improves greatly the predictive capability of the proxy.
Forest disturbance shapes interactions between lianas-trees and epiphytic ferns
Ainhoa Magrach, James Cook University
Javier Rodriguez Perez, Universidad de Oviedo
Mason Campbell, James Cook University
William F. Laurance, James Cook University
Tropical forests host an important part of the diversity of lianas and epiphytic ferns. Despite much has been studied on how the fragmentation of these forests leads to changes in their diversity and composition, we lack information on how forest disturbance affects the spatial pattern of distribution of many of the organisms that inhabit these particularly diverse ecosystems. I mapped the distribution of different guilds of lianas, trees and two genus of epiphytic ferns (Asplenium and Platycerium) in plots located at increasing distances from the nearest forest edge and in different-sized remnant fragments of rainforest in the Atherton tablelands, Far North Queensland, Australia. I used spatial point-pattern analysis to better understand the role of forest disturbance on the shaping of the distribution of these organisms as well as the interactions that occur between them. To this end, I used specific point-process models to analyse the impact of habitat suitability (in relation to forest disturbance) as well as the size of trees and the presence of other lianas and epiphytic ferns. I will show some preliminary results on the importance of forest disturbance and how it leads to cascading changes in the distribution of particular species.
Forests of southern Chile and New Zealand: how are similarities and differences in structure reflected in ecosystem functioning?
Juan Armesto, Departamento de Ecologia, Pontifica Universidad Catolica de Chile, Santiago
Matt McGlone, Landcare Research, Lincoln, New Zealand
The long, narrow, mountain-bordered landmasses of southern Chile and the New Zealand archipelago have many climatic and topographic similarities, and biogeographical connections extend back to Gondwana. It is no surprise then that their forests are often thought of as sharing a southern temperate forest syndrome. The presence in both regions of trees of Nothofagaceae, Winteraceae, Proteaceae, Elaeocarpaceae, Podocarpaceae and Araucariaceae, the dominance by complex conifer-angiosperm, liana and vine-rich forests in the lowlands, and conifer-Nothofagus communities in the uplands, makes for close resemblances. However, there are some striking differences as well. New Zealand forests have a much greater number of tree species; woody species have a high percentage of gender dimorphism; deciduous species are never prominent, and tree ferns are conspicuous in lowland understoreys. Chile, while having approximately the same number of woody genera has about one third the number of tree species, gender dimorphism is low; deciduous trees play a prominent role in mediterranean–temperate climates and at timberline; and tree ferns are absent but native bamboos important. Climate, geography, geology, and history have clearly all played a role in producing these striking similarities and important differences. Here we discuss how these factors have shaped the patterns of southern forests, and explore the issue of whether structural similarities and differences between forests in Chile and New Zealand affect ecosystem function.
Fossil- and biogeographic evidence for the role of dispersal in the assembly of the Cenozoic Australian rainforest flora
Kale Sniderman, University of Melbourne
Greg Jordan, University of Tasmania
The Australian rainforest flora is currently interpreted as essentially a Gondwanan relict. We examine this entrenched concept, using an analytical, whole-of-flora approach integrated with the fossil record. We identify disjunctions between woody Australian rainforest taxa and their relatives on other land masses, and evaluate the proportion of disjunct clades represented in the Australian fossil record. To minimize the effects of biases in this record, we compare late Oligocene–early Miocene, Pliocene, and Quaternary Australian pollen records interpreted as rainforest. Using within-species disjunctions as a proxy, we assessed the role of recent immigration from Asia into Australia. To assess the role of source–sink dynamics, we performed comparative analyses of disjunctions in major rain forest categories representing a north–south/climatic gradient. Our results indicate that microthermal rain forests are largely Gondwanan relicts, but there is progressively greater, and more recent contributions from Asia/ Malesia into more northern, and more lowland tropical rainforests. This variation reflects a strong gradient in geographic and ecological proximity between these forests and source floras in Asia/Malesia, and is consistent with a source–sink size model of immigration driven by late Cenozoic contractions and expansions of Australian rainforest. Rates of recent immigration from Asia/Malesia are high in northern forests, and outweigh rates of recent emigration approximately nine-fold. The late Quaternary fossil record has many more rain forest angiosperms than Oligocene–Miocene and Pliocene floras, consistent with extensive late Cenozoic immigration.
Fossils and forests: a botanical tour of New Caledonia
Raymond J. Carpenter, University of Adelaide
Jennifer Read, Monash University
The New Caledonian flora is discussed, with a focus on some of its more extraordinary elements, and with respect to the Southern Hemisphere fossil record and some ecological insights from long-term (some >20 years) permanent vegetation plots. Most extant conifer genera and several angiosperm lineages are represented at fossil sites remote from the island. Of note are numerous conifers in the Tasmanian Paleogene, including Acmopyle and Libocedrus. There is also fossil evidence that the endemic angiosperms Beauprea and Strasburgeria were much more widespread in the past. Mesic, humid, frost-free climates are likely to have supported the persistence of such taxa in New Caledonia. Recent and ongoing research shows that the establishment of forest canopy monodominance of Nothofagus at some sites parallels that for better known temperate Nothofagus species: it generally reflects episodic, large-scale disturbance events. Some of the other endemic forest trees that occur on the plots also exhibit unusual and fascinating ecological traits. For instance, Cerberiopsis candelabra (Apocynaceae) is monocarpic, and Myodocarpus (Apiales) has winged propagules, and these traits do not occur in their respective sister taxa. The evolutionary drivers of these novel traits are probably related to features of the New Caledonian environment, such as the combination of nutrient-deficient soils, high incidence of cyclonic winds and strong topographical diversity.
Frugivory and seed dispersal in Chile and New Zealand: contemporary processes and network structure
Juan L. Celis-Diez, Institute of Ecology and Biodiversity and P. Universidad Católica de Chile, Santiago, Chile
Rocio Jaña, School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
Tarryn E. Wyman, School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
Archie Macfarlane, School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
Dave Kelly, School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
Temperate forests in Chile and New Zealand have similar biogeography observed in similar vegetational units and biotic interactions. Plant-bird interactions are a common feature in ecosystems in both countries, however, in New Zealand introduced mammalian predators have drastically reduced bird species diversity and abundance. As an example, 77% of the original seed-dispersing fauna (10 out of 13 species) are now extinct globally or functionally (populations too small to contribute significantly to seed dispersal). However, a recently-arrived native bird (Zosterops lateralis, Zosteropidae) and three introduced European species (two Turdidae and one Sturnidae) are now widespread and abundant in New Zealand, and dispersing seeds of native and exotic plants. In contrast, in Chilean temperate forests, there have been no extinctions and introductions, and the disperser assemblages still resemble those existing before the Spanish colonization. Our aim in this symposium is to explore the differences and similarities between the Chilean and New Zealand frugivore-plant interaction networks as a consequence of human colonization and land use change. To do this, we will construct qualitative frugivore-plant interaction networks based on published records and field data. We expect to find more similarities between present frugivore-plant interaction networks in both countries, mainly due to the current exotic bird species dispersing seeds in New Zealand temperate forests.
Fuel treatment effectiveness in the United States: assessing site- and landscape-level effects of fuels treatments on wildland fires
Cochrane, Mark A, South Dakota State University
Christopher J. Moran, South Dakota State University
Michael C. Wimberly, South Dakota State University
M.A. Finney, USDA Forest Service
J. Eidenshink, US Geological Survey Center for Earth Resources Observation and Science
Z. Zhu, US Geological Survey
Understanding the influences of forest management practices on wildfire severity and spread are critical in fire-prone ecosystems of the United States. Human land use practices, altered climates, and shifting forest and fire management policies have increased the frequency of large wildfires several-fold. Mitigation of potential fire behavior and fire severity have increasingly been attempted through pre-fire alteration of wildland fuels using mechanical treatments and prescribed fires. Despite annual treatment of more than million hectares of land, comparative quantitative assessments of the effectiveness of existing fuel treatments at reducing the size or severity of actual wildfires or how they might alter the risk of burning across landscapes are currently lacking. Newly available geospatial datasets characterizing vegetation, fuels, topography, and burn severity offer new opportunities for studying fuel treatment effectiveness at regional to national scales. We utilized the Monitoring Trends in Burn Severity (MTBS) fire perimeters in combination with LANDFIRE datasets and ancillary information on weather during wildfires and fuels treatments to create multiple FARSITE simulations of 87 historical wildfires to estimate spatial probabilities of burning as a function of the extant fuels treatments across the wildland fire-affected landscape. Fuels treatments effectively redistribute fire risk on the landscape by changing surface fire spread rates and reducing the likelihood of crowning behavior. Trade offs are created between formation of large areas with low probability of increased burning and smaller, well-defined regions with reduced fire risk.
GIANT EUCALYPT FORESTS – A GLOBALLY UNIQUE FIRE-ADAPTED RAIN FOREST?
Tng YPD, Unknown
Williamson GJ, Unknown
Jordan GJ, Unknown
Bowman DMJS, Unknown
Tree species exceeding 70m in height are rare globally. Giant gymnosperms are concentrated
near the Pacific coast of the USA while the tallest angiosperms are eucalypts (Eucalyptus spp.) in
southern and eastern Australia. Giant eucalypts co-occur with rain forest trees in eastern Australia
creating unique vegetation communities comprising fire-dependent trees above fire-intolerant
rain forest. However, giant eucalypts can also tower over shrubby understoreys (e.g. in Western
Australia). The local abundance of giant eucalypts is controlled by interactions between fire
activity and landscape setting. Giant eucalypts have features that increase flammability (e.g. oil-
rich foliage and open crowns) relative to other rain forest trees but it is debatable if these features
are adaptations. Probable drivers of eucalypt gigantism are intense intra-specific competition
following severe fires, and inter-specific competition amongst adult trees. However, we suggest that
this was made possible by a general capacity of eucalypts for “hyper-emergence”. We argue that
because giant eucalypts occur in rain forest climates and share traits with rain forest pioneers they
should be regarded as long-lived rain forest pioneers, albeit with a particular dependence on fire
for regeneration. These unique ecosystems are of high conservation value, following substantial
clearing and logging over 150 years.
GLORIA in New Zealand: Progress with monitoring at two sites.
Alan F. Mark, Department of Botany, University of Otago, Dunedin, New Zealand.
Janine Wing, Department of Botany, University of Otago
Katharine J.M. Dickinson, Department of Botany, University of Otago.
GLORIA is a world-wide standardised, low-impact, alpine observation network, to monitor long-term changes in plant diversity and temperature, initiated by the University of Vienna Mountain Research Institute in 2000. It now has 42 “Target Regions” worldwide. Two were set up in contrasting environments, on conservation land in southern New Zealand. A perhumid Fiordland site was established Nov. 2001 on a 3-aspect well-defined summit (no W-aspect present but an additional crest site was established) at 1420 m on Mt Burns (1650 m), near the lower limit of several high-alpine species. Two sites were established on the Pisa Range in sub-continental Central Otago in early 2004, on a low summit on the crest, in high-alpine cushionfield at 1885 m, and on a steeper summit in degraded Chionochloa macra tussockland at 1647 m. Standardised procedures were used for both vegetation and soil temperature measurements. Air temperature was measured on all three crests. Vertical digital images of quadrats were also recorded. Loggers were serviced annually and temperature data analysed for monthly extreme and mean maxima and minima as well as true mean values. Results of vegetation resampling on Mt Burns after one decade are unclear due to ‘noise’ associated perhaps with observer effects (only one of 14 persons (AFM) involved in both samplings): weather, terrain and equipment were not factors. Predictably sensitive high-alpine species gave no better results, while temperature values are also inconclusive. Recent analyses of 60 summit sites throughout Europe indicate that a continental-scale is more indicative than individual mountains.
Grazing and environment interactions in the forest-steppe complex of Southern Patagonia
Grant Wardell-Johnson, Curtin Institute for Biodiversity and Climate, School of Science, Curtin University, Bentley, WA 6845, Australia
Pablo L. Peri, Universidad Nacional de la Patagonia Austral (UNPA), Consejo Nacional de Investigaciones Cientificas y Técnicas (CONICET)
Ladislav Mucina, Curtin Institute for Biodiversity and Climate, School of Science, Curtin University, Bentley, WA 6845, Australia
Romina G. Lasagno , INTA EEA-Santa Cruz, cc 332 (9400), Río Gallegos, Santa Cruz, Argentina
Grazing impacts have been particularly profound in high latitude environments such as in southern Patagonia. However, differential effects of grazing on different environments and on phylogenetic patterns remains unclear. We carried out a floristic (141 site x 275 species matrix using 1000 m2 quadrats) and environmental assessment (16 edaphic, 16 climate variables) based on four levels of grazing (undisturbed vegetation, low, medium and high stocking rate) across the environmental variation in southern Patagonia, Argentina. We sought to determine the influence of edaphic and climatic environment on the overall floristic pattern, and whether there was a differential influence of grazing across the three main vegetation types assessed (forest, shrubland, grassland). We found that grazing does not appear to have a controlling effect at the landscape level (all vegetation types, including wetlands considered), but it does show influence at the lower scales (distinction between woody and non-woody vegetation; partly also within the forests). Phylogenetic composition (i.e. total phylogenetic branch length) was considerably altered by grazing. Thus a possible regime shift is suggested in areas previously considered less affected by grazing – the forests and shrublands in particular. Thus the total evolutionary potential of these environments is likely to be impacted by grazing, with significant implications for climate change adaptation.
He kitenga no te moana, He kitenga no te whenua Views from the land and the sea
Michael Walker, School of Biological Sciences, University of Auckland
The entry of the Austronesians into the western Pacific led to development of oceanic navigation systems that permitted discovery and colonisation of Madagascar in the Indian Ocean, the habitable islands of the tropical Pacific and temperate New Zealand, and contact with indigenous societies in South America. This presentation explores responses to: (1) the ocean in culture formation in eastern Polynesia; (2) the absence of written languages; and (3) the construction of knowledge of their world by the eastern Polynesians, including Maori in New Zealand. The ocean clearly linked rather than separated Polynesian societies that voyaged extensively and held widespread knowledge of the distributions of islands in the tropical Pacific. Despite not having a written language, the Polynesians applied a systematic understanding of their world in ways that supported flourishing societies. The challenge and the opportunity for New Zealand as a society lie in the differences in culture, history and language between Māori and Non-Māori and the lessons for global society that may arise from societies who have lived within their ecological means for long periods.
Hidden beneath the surface: exploring the evolution and systematics of Nedsia, a subterranean amphipod genus from the Pilbara region of West Australia
Fagan-Jeffries E. , Australian Centre for Evolutionary Biology and Biodiversity, School of Earth and Environmental Science, The University of Adelaide
R. King , Australian Centre for Evolutionary Biology and Biodiversity, School of Earth and Environmental Science, The University of Adelaide;Evolutionary Biology Unit, South Australian Museum
A. Austin , Australian Centre for Evolutionary Biology and Biodiversity, School of Earth and Environmental Science, The University of Adelaide
The subterranean fauna of Western Australia is proving to have an exceeding large amount of hidden and previously unknown diversity. Beneath the surface of the Pilbara are numerous overlayed alluvial and carbonate calcrete aquifers containing stygofauna dominated by crustaceans such as amphipods. The genus Nedsia is a poorly known group belonging to the Melitidae, a family in which almost all other subterranean genera apart from Nedsia are currently monotypic. This study assembled and utilised the specimens and information from extensive sampling conducted by various environmental consultancy companies and researchers over the last decade. Morphological examinations and molecular data from multiple genes were used to confirm the monophyly of Nedsia, to investigate the relationships with other known genera of Melitidae, and to explore species boundaries within Nedsia. A surprisingly large amount of genetic diversity within the genus was revealed, with some clades possessing unique morphological characters whilst others are possibly morphologically cryptic. Some clades appear to be highly endemic and confined to one drainage basin. These results emphasize the conservation importance of these unique habitats beneath the surface of Western Australia.
High-resolution Holocene records from 2 adjacent crater lakes in western Victoria: new information for comparison across the southern hemisphere
Patrick De Deckker, Australian National University
Christos Gouramanis, Earth Observatory of Singapore, Nanyang Technological University
Daniel Wilkins, Australain Antarctic Division
Matthias Moros, Baltic Sea Research Institute
Kerstin Perner, Baltic Sea Research Institute
Claudia Moros, Baltic Sea Research Institute
The classic Holocene record of the crater Lake Keilambete has been revisited in great detail and is paralleled with the record of another crater lake located nearby. The new records document more lake level fluctuations than previously known and are backed by substantial chronological framework based on numerous 14C ad OSL dates. Some of the level fluctuations were quite rapid and extensive. Another finding is that the last 600 years saw lake levels progressively dropping.
These lacustrine records are compared against a high-resolution marine record obtained from offshore southern Australia. Detailed SST were also reconstructed from this core and are compared against the lake level changes. It also has been possible to determine the extent of the water column stratification at the deep-sea core site with implication for the westerly wind belt offshore Australia, and by correlation with rainfall inland
Holocene environmental change in sub tropical eastern Australia. Evidence from geochemical and biological proxies.
Dr Kathryn Taffs, Southern Cross University
Sarah Hembrow, Southern Cross University
Dr Pia Atahan, Australian Nuclear Science and Technology
Dr Jeff Parr, Southern Cross University
Climate change is impacting global surface water resources, increasing the need for a deep understanding of the interaction between climate and aquatic biological diversity. Yet, little information exists concerning freshwater resources as a result of inadequate environmental monitoring programs and availability of suitable sites. Lake McKenzie, Fraser Island (Australia), was used to investigate the interactions between climate influences and aquatic ecosystems. This study utilises a combination of proxies including biological (diatom), geochemical and chronological techniques to investigate long term aquatic changes within this perched dune lake. A combination of 210Pb and AMS 14C dates show the retrieved sediment to represent a history of ca. 37,000 cal. yBP. A sediment hiatus was observed between ca. 18,000 and 13,000 cal. yBP, suggesting a period of dry conditions at the site. The diatom record shows little variability over the period of record, with benthic, freshwater acidic tolerant species dominating. Relative abundance of planktonic species and geochemical results indicate a period of increased water depth and lake productivity in the early Holocene but a gradual decrease in effective precipitation throughout the Holocene. Results from this study support earlier work conducted on Fraser Island using pollen reconstructions but also demonstrate that aquatic biological diversity has been relatively consistent throughout the Holocene and late Pleistocene with only minor cyclical fluctuations evident.
Holocene fire regimes and vegetation change from the seasonally Dry Tropics of north-eastern Australia
Patrick Moss, The University of Queensland
Lydia Mackenzie, The University of Queensland
Sean Ulm, James Cook University
Michael Bird, James Cook University
Craig Sloss, Queensland University of Technology
Christopher Wurster, James Cook University
James Shulmeister, The University of Queensland
Lynley Wallis, The University of Queensland
Recent research from two sites within the seasonally Dry Tropics of north-eastern Australia have provided new information on Holocene fire regimes and associated vegetation change within this region. The first site, Mirdidingki Swamp located on Bentinck Island in the southern Gulf of Carpentaria, provides evidence of a significant alteration in fire regimes following human abandonment of this island during the mid to late 20th century and the subsequent return of people in the late 1980s. This record can be used to assess the relative role of human and natural climate fire regimes during a period that has good historical documentation of human habitation, along with direct ethnographic evidence of how indigenous people utilized burning. The second site, Kinrara, situated within 100 km of the well-studied Atherton Tableland region provides an almost complete Holocene (i.e. last 10,000 years) record of landscape change for the Dry Tropics on north-eastern Australia. Alterations in carbonized particle and vegetation representation (i.e. sclerophyll forest, grassland, salt-marsh and aquatic taxa) appear to reflect climatic alterations, possibly associated with changes in the Australian monsoon linked to climatic variability associated with the El Niño Southern Oscillation (ENSO) phenomena.
How connected are the sub-Antarctic islands?
Peter Convey, British Antarctic Survey
The sub-Antarctic islands are an often overlooked series of islands and archipelagos. They share features such as extreme geographical isolation and chronically cool environmental conditions. There are also important differences, most obviously in their age and geological origins, and their historical and current levels of glaciation. Their locations, within the latitudes of the circumpolar westerly winds and close to the oceanic Antarctic Polar Front and Circumpolar Current, provides both oceanic and atmospheric connectivity. Their terrestrial biotas are exceptional globally, with an almost complete absence of native terrestrial vertebrates and invertebrate-dominated ecosystems. A range of biodiversity patterns are present amongst the native biota, from single island endemics, through species restricted to particular oceanic provinces and showing affinity with the nearest larger landmasses, to more circum-Antarctic distributions – with wind dispersal being strongly implicated in the dispersal of the latter. There are also tantalising suggestions that the biota may include relictual components signalling earlier dispersal from a more southern Antarctic sources. Few studies have yet applied modern molecular phylogeographic approaches to the sub-Antarctic biota, but there is evidence both for early colonisation by contemporary species as opportunity became available, including on multi-million year pre-Pleistocene timescales and, particularly towards the Scotia arc, of colonisation occurring counter to the prevailing winds and currents. These patterns are today being compromised by human activity, through transfer of non-native species into the region, this far outweighing natural colonisation events, and the potential for intra-regional tranfer of native biota between previously isolated areas.
How exotic species integrate into pollination networks
Daniel B. Stouffer, University of Canterbury
Jordi Bascompte, Estación Biológica de Doñana (EBD-CSIC)
There is increasing worldwide concern about the impact of introductions of exotic species on ecological communities. In this talk, we quantify how exotic species integrate into pollination networks---the network of mutually-beneficial interactions within a community of flowering plants and their animal pollinators---as well as the expected long-term consequences of this integration. To do so, we use a database of empirical pollination networks, covering distinct communities found across the globe, and systematically compare the properties of exotic plant species to their native counterparts. We find that, in terms of species-specific properties, exotic species are virtually indistinguishable from native species. For example, they neither tend to have fewer or more interactions than native species nor do they tend to be more or less phylogenetically related to those species already present.
Though the species themselves are not dissimilar, we do observe statistically-significant differences between the species with whom exotic species preferentially interact and those with whom they don't. Intriguingly, and in contrast to earlier studies, the exotic species found across the different communities exhibit a stronger tendency to interact with specialist or moderately-specialist pollinators than they do with generalists. Additionally, exotic species tend to interact with pollinators whose intrinsic dynamics are most likely to lead to their extinction. Overall, our results indicate that a successful introduction into a pollination network depends more strongly on the composition of the invaded community than in the characteristics of the invading species.
How will New Zealand frogs fare in the face of climate change?
Phil Bishop, Department of Zoology, University of Otago
Amphibians in New Zealand are currently represented by 4 endemic and 3 introduced species of frogs. All the endemic species and two of the introduced species are listed by the IUCN as Threatened. The endemic frogs are reliant on either small, stable, perennial first order streams for their aquatic larvae or sufficient humidity to allow terrestrial breeding and juvenile recruitment. They occur mainly in native forests from about 350 m to 800 m above sea level. The threatened introduced species prefer flooded grasslands and agricultural ponds at low levels and their microhabitat distribution does not often overlap with the endemic species. As the introduced species originated in Australia, it is possible that they may actually benefit from short-term climate change in New Zealand. The endemic leiopelmatid species are well adapted to the cool temperate climate of New Zealand and are likely to be severely adversely affected. It is possible that given the 2080 climate change predictions, the area of suitable habitat for endemic frogs may actually increase, but given their low dispersal ability and their already fragmented populations, it is likely that climate change will contribute to their decline unless active conservation management in the form of translocations is implemented.
Additionally, in the face of climate change New Zealand may become suitable as an ‘amphibian ark’, with the absence of endemic frogs on the South Island making it suitable for assisted colonisation of threatened species such as the Corroboree frog (Pseudophryne corroboree) from other countries.
Human-caused and climate-driven thresholds in past fire activity: insights from paleoecological studies in temperate forests
Cathy Whitlock, Montana State University
Simon Haberle, Australian National University
Dave McWethy, Montana State University
Virginia Iglesias, Montana State University
Laurie Stahle, Montana State University
Fire is a catalyst of ecosystem change worldwide, but the extent to which humans versus climate create fire regimes is a topic of considerable debate. Disagreement centers on the importance of prehistoric peoples in shaping vegetation through deliberate burning versus the role of climate variability in creating fire weather and flammable vegetation. In some regions, the signature of anthropogenic burning is clear: for example, 40% of New Zealand’s forests were lost through fires soon after human arrival, whereas climate played relatively little role. In other regions (e.g., western U.S., Patagonia), prehistoric people boosted ignitions or amplified the effects of naturally-caused fires through fuel manipulations, even though climate change appears to be the dominant force in altering fire regimes. In Tasmania’s wet forests, the forest-moorland mosaic is ascribed to human-set fires, but its persistence through time is also controlled by edaphic conditions and climate change. In southern Patagonia, effective moisture variations determined the east-west position of the forest-steppe border, but anthropogenic burning likely contributed to the ecotonal character. To advance understanding on this topic, a more-nuanced approach is required. For example, identifying the climate signal in fire-history reconstructions can disclose residual nonclimatic controls. Consideration of the flammability of different post-fire seral stages can identify thresholds where additional fire will render a new stable state. Finally, simple correlations of fire use with human population size/density need to be replaced by models that consider different fire needs required for particular resource utilization.
Identifying refugia in a warming, drying global biodiversity hotspot
Grant Wardell-Johnson, Curtin Institute for Biodiversity and Climate, School of Science, Curtin University, Kent St, Bentley, Western Australia, Australia
Kimberly Van Niel, School of Earth and Geographical Sciences, The University of Western Australia, Crawley, Western Australia, Australia
Colin Yates, Science Division, Department of Environment and Conservation, Locked Bag 104, Bentley Delivery Centre, Western Australia, Australia
Antonius G. T. Schut, Department of Spatial Sciences, Curtin University Kent St, Bentley, Western Australia, Australia
Margaret Byrne, Science Division, Department of Environment and Conservation, Locked Bag 104, Bentley Delivery Centre, Western Australia, Australia
Gunnar Keppel, School of Natural and Built Environments, University of South Australia, GPO Box 2471, Adelaide, SA, Australia
Stephen Hopper, Royal Botanic Gardens Kew, Richmond, Surrey, UK, 7School of Plant Biology, The University of Western Australia, Crawley, Western Australia, Australia
Ladislav Mucina, Curtin Institute for Biodiversity and Climate, School of Science, Curtin University, Kent St, Bentley, Western Australia, Australia
Steven Franklin, Trent University, Peterborough, Ontario, Canada
Refugia are habitats where species can contract to, persist in and expand from as the regional climate changes. Therefore they have potential for facilitating the regional persistence of biodiversity under anthropogenic climate change, and are critically important in climate change adaptation management. The identification of refugia is problematic in drying landscapes of subdued topography; exemplified by the South-western Australian global biodiversity hotspot. In the landscapes of this region, refugia must provide protection against three increasing environmental stressors: reduced moisture availability, increasing fire severity and more frequent extreme temperature events. We review spatially explicit evidence for refugia in the region, based on the distribution of environmental (e. g. water, temperature, fire) and biological processes (species traits, phylo and phytogeography). High resolution spatial data, phylogeography, ecophysiology and community data provides an integrated, transdisciplinary framework for the identification and management of refugia in the region. Current environmental and biotic signals such as high habitat heterogeneity, increased vegetation height and vigour, and populations outside their predominant range are good indicators for areas serving as refugia. Historical signals from the ecological and evolutionary dynamics of plant communities (i.e. species traits), and from phylogeographic patterns also separate refugia from the surrounding matrix. Particular riparian habitats, granite outcrop systems, high rainfall forest ecosystems and the few mountain ranges of limited extent provide a wide range of habitats with specific refugial characteristics. Experimental hypothesis testing is now needed to materially advance the understanding developed from our correlative and observational findings.
Identifying transitional biotic turnover zones and their association with climate, topography and lithology
Giovanni Di Virgilio, University of New South Wales
Shawn Laffan, University of New South Wales
Malte Ebach, University of New South Wales
Groups of co-occurring species have long been identified according to the biogeographic boundaries or ‘breaks’ that delineate them (e.g. the Wallace Line) and the transition zones between these breaks. However, distributions are frequently depicted as thematic species range maps and phylogeographical boundaries and breaks as solid, uniform lines. This does not reflect the reality that breaks, transitions and ecoregion boundaries are often gradational. Moreover, the scope of many studies is at continental to global extent, at coarse analysis resolution, and the physical drivers of breaks may be poorly understood. Using moving window analyses of anisotropic species turnover in native Australian flora and fauna, biogeographic breaks and transitions can be identified and mapped at local to regional extents and depicted in detailed maps of 2.5 km resolution. Further, by studying environmental turnover in locations of break and transition zones, we can infer the relative contribution of different physical factors to driving break formation. I present the biotic and environmental breaks and transitions our approach has identified in a topographically complex area of 17,000 km2 in south-eastern Australia, and consider the generality of this approach for other regions and scales, and its applicability to fields such as conservation management.
Improving the Accuracy and Consistency of Taxonomic Identifications in Climate Change Studies
Norman MacLeod, The Natural History Museum
David Steart, The Natural History Museum
Accurate and consistent identifications of taxonomic species are a critical aspect of climate studies, not only in terms of documenting the effect of climate change on organismal populations, but also in support of studies that seek to infer Cenozoic climate history. At present the consensus among the geoscience community is that palaeontologists who are considered experts in the taxonomy of an organismal group can be relied upon to supply species identifications that are 100% accurate 100% of the time. This assumption is difficult to substantiate and flies in the face of all the (admittedly small number of) empirical studies that address this issue. Results from a suite of investigations into the levels of accuracy, consistency, and speed of current technological and algorithmic approaches to this problem (e.g, multivariate analysis of form factors, geometric morphometric analysis of landmark configurations and /or outlines, approaches that combine machine learning with computer vision) undertaken over the last five years indicate that virtually any quantitative procedure delivers results that are (1) more accurate, (2) more consistent, and (3) achieved with greater speed than single or collective groups of human expert(s). In particular, such approaches can be used to improve transfer-function and/or modern analogue-based sea-surface temperature estimates of a variety of climate factors derived from leaf physiography analyses. Sustained engagement with, and improvement of automated identification systems represents the only large-scale option for delivering high-quality taxonomic identifications and developing, research-level taxonomic expertise for many fossil groups.
Incorporating geographic ranges into measures of species and phylogenetic turnover
Shawn W. Laffan, UNSW
Dan F. Rosauer, ANU
Brent D. Mishler, UC Berkeley
Joseph T Miller, CSIRO Plant Industry
Nunzio Knerr, CSIRO Plant Industry
Carlos E. González-Orozco, CSIRO Plant Industry
Andrew Thornhill, CSIRO Plant Industry
Measures of turnover are used to estimate the rate of change of species, or phylogenetic, composition between sets of sites. These are important for our understanding of the spatial distribution of biodiversity across geographic and environmental gradients, and are of particular importance for the identification of geographic breaks and transition zones for collections of organisms. A key aspect of existing turnover metrics is that they assign an equal weight to all taxa used in the calculations. However, when searching for geographic breaks it is possible that wide ranging taxa that span a break or transition zone will dominate the results, lessening the measured turnover and making the identification of such breaks more difficult. We have developed a set of range-weighted turnover measures for both species and phylogenetic turnover, implemented within the Biodiverse software (http://purl.org/biodiverse). These measures weight the relative contribution of each taxon, or branch in a phylogenetic tree, by the proportion of their geographic ranges that are found in the sites for which the turnover is calculated. In this way the measures result in higher turnover scores when those taxa that are different between sites have narrow ranges, and lower turnover when those taxa that are different are wide ranging. We demonstrate the turnover measures using a continental extent data set of Acacias in Australia, including a 520 species phylogeny. The measures described have potential to be used as drop-in replacements for standard measures in analyses such as agglomerative clustering, moving window analyses, and Generalized Dissimilarity Modelling.
Indicators of biodiversity status in temperate grasslands: Integrating multiscale measures for environmental accounting and product certification
Stephan Halloy, The Nature Conservancy and Universidad Nacional de Chilecito
Gustavo Iglesias, The Nature Conservancy
Mercedes Ibáñez, The Nature Conservancy
Donald Bran, Intituto Nacional de Tecnología Agropecuarias
Juan Gaitán, Intituto Nacional de Tecnología Agropecuarias
Jerry Touval, The Nature Conservancy
Tim Boucher, The Nature Conservancy
Understanding the conservation value of managed grasslands is one of the great challenges for conservation under sustainable management. Companies wanting to demonstrate good management for biodiversity in the supply chains for their products require replicable, transparent and economic methods to validate their claims to customers. Most approaches to managing for biodiversity sustainability have used by default the same tools as management for productive landscapes, i.e. soil condition, biomass and net primary productivity. The assumption that these features relate to biodiversity is often unwarranted, and independent indicators of biodiversity are needed. The Patagonia sustainable grazing project is exploring measures from the ground to remote sensing; from water to soil; from microbes to plants; aiming eventually for simple indicators which can be used in labeling for products that incorporate conservation values. Among the initial indicators tested, plant and insect abundance distribution curves distance to the lognormal (∆L) have demonstrated sensitivity to grazing management and (for plants) a possibility to relate ground measures to remote sensing coefficient of variation of NDVI measures. High seasonal, interannual and spatial variability require a capability to distinguish signal from noise in these analyses (including phenomena like the 2011 Puyehue volcanic ashfall). Moving climate niches can now be incorporated into management recommendations and planning for biodiversity movements and corridors.
Inferring biogeographic pathways in Centipeda (Asteraceae) by means of geographic diffusion in a species tree environment.
Stephan Nylinder, Swedish Swedish Museum of Natural History, Stockholm, Sweden
Bodil Cronholm, Swedish Swedish Museum of Natural History, Stockholm, Sweden
Peter J. de Lange, Department of Conservation, Auckland, New Zealand
Neville Walsh, Natural Herbarium of Victoria, Victoria, Australia
Philippe Lemey, Department of Microbiology and Immunology, Katholieke Universitet Leuven, Belgium
Bernard Pfeil, Department of Biological and Environmental Sciences, Gothenburg University, Sweden
Arne A. Anderberg, Swedish Swedish Museum of Natural History, Stockholm, Sweden
Ancestral area analyses of species have recently taken a leap forward in the development of allowing simultaneous estimation of node heights (molecular dating) and internal node locations while integrating over the uncertainty of the topology. Such models are now present in the software BEAST, allowing geography to be diffused on a genealogy as a multi-dimensional continuous trait. However, BEAST also allows for estimation of a species tree based on multi-species multi-locus data. Here, for the first time, we infer a species tree based on marginal gene trees using both nucleotide and binary data, while simultaneously diffusing geographic locations for internal nodes and root location. We compare two separate approaches to estimate ancestral geographic distributions of species. One is by time slicing the species tree based on diffusion on gene trees from individual information on specimen sampling locations. The other infers node locations directly on the species tree using approximated species probability distributions. By applying mentioned approaches to the phylogeny of the small genus Centipeda we can present a detailed hypothesis on the species diffusion pattern of the group in Australasia in real time and space.
Informing sustainable land management in the Andes by mapping and ground-truthing biome shifts with climate change
Stephan Halloy, The Nature Conservancy
Mercedes Ibáñez, The Nature Conservancy
Erica Simek, The Nature Conservancy
Kirk Klausmeyer, The Nature Conservancy
Karina Yager, NASA, Goddard Space Flight Center
Juan José Rodríguez, The Nature Conservancy
Fernando Ghersi, The Nature Conservancy
Gustavo Iglesias, The Nature Conservancy
Paulo Petry, The Nature Conservancy
Evan Girvetz, The Nature Conservancy
Anton Seimon, Wildlife Conservation Society
Climate in the form of temperature and precipitation largely determines the global distribution of major biome types. In conjunction with models that predict climate change this can be used to anticipate major biome shifts that are likely to impact conservation sites and productive activities. The central Andes are expected to experience some of the fastest changing climate in all of Latin America. Climate envelopes are calculated using the seasonal development of temperature and precipitation, much more informative than annual means alone. We compare shifts projected from General Circulation Models with A2 emission scenarios to past trends in the same areas as a coherence check. Global Research Initiative in Alpine Environments (GLORIA) monitoring sites provide ground-checking at 10 sites in this region. Monthly water balance indices were calculated for present and future, corresponding closely to biome distributions. Because of increases in temperature, and thus evapotranspiration, most sites are predicted to have decreasing water balances. We provide information on potential climate envelope displacement in a manner that is directly useful for decision makers and planning of corridors and migrations as species change and adapt on heterogeneous landscapes. We also propose methods to anchor such projections from global, large scale models, to specific historical datasets to show that, on a case by case basis, there is potential to provide practical advice as to historical vs. projected trends.
Insights from the St Bathans Fauna on the Early Miocene land and freshwater animals of Zealandia
Trevor H. Worthy, University of Adelaide
University of Adelaide, J.P. Worthy
University of New South Wales, M. Archer
University of New South Wales, S.J. Hand
Canterbury Museum, R.P. Scofield
Museum of New Zealand Te Papa Tongarewa, B.A. Marshall
4Museum of New Zealand Te Papa Tongarewa, A.J.D. Tennyson
University of Queensland, S. Salisbury
The St Bathans Fauna derives from the lacustrine Early Miocene Bannockburn Formation in outcrops around St Bathans, Central Otago. Its diverse fauna includes: MOLLUSCA - 11 terrestrial & freshwater species, 6 families; TELEOSTS – 15 species, 6 families, with 3 (Galaxiidae 6 spp., Eleotridae 4 spp., Retropinnidae 2 spp.) the principle fish inhabitants of palaeolake Manuherikia; AMPHIBIA – Leiopelma (2 spp.) & a neobatrachian frog; REPTILIA – a crocodilian, a ?meiolaniid turtle, a sphenodontid, and 2 skinks & 2 geckos; AVES – minimally 39 spp. (dinornithiforms, kiwi, diving petrel, waterfowl, raptors, herons, Aptornis, rails, waders, pigeons, parrots, owlet-nightjars, swiftlets, and passerines); MAMMALIA – 5 bats (Mystacinidae 2 spp., fam. nov. 1 sp., a vespertilionid, 1 indeterminate sp.), and a terrestrial form (order & family indeterminate).
The St Bathans Fauna offers overwhelming evidence refuting total drowning of Zealandia during the Oligo-Miocene. (1) High endemicity at all taxon levels with no species and few genera (e.g., the birds Palaelodus, Aegotheles, Collocalia) shared with Australia. Notably, there are no shared anseriform genera despite equivalent-aged lacustrine faunas dominated by waterfowl in Australia. (2) It has all of the iconic ‘old endemics’ of New Zealand long assumed of vicariant origin (e.g. sphenodontids, leiopelmatids, dinornithiforms, apterygids, acanthisittids), implying no such animals dispersed to NZ in the subsequent 16+ Ma. (3) Extinction, especially of major high level taxa e.g. crocodilians, turtles, swiftlets, palaeolodids, and several mammals, in combination with dispersal of new lineages, has been a significant faunal modifier subsequently.
Insights into historical and contemporary differentiation in New Caledonian Araucaria
Pete Hollingsworth, Royal Botanic Garden Edinburgh
The New Caledonian flora is characterised by high levels of endemism, and a particularly high diversity of endemic conifer species. Using a combination of GIS and distributional analyses, transcriptome sequencing, complete plastid genome sequencing, and comparative population genetic studies across all 13 species in the genus Araucaria in New Caledonia, we have assessed (a) the timing of the New Caledonian radiation, in the context of fossil record of the Araucariaceae, (b) the phylogenetic relationships among New Caledonian species in relation to their ecology, (c) the extent and spatial distribution of the ‘environmental space’ occupied by each species, and (d) the spatial scales and landscape context in which populations become isolated. We have used these multiple lines of evidence to increase our understanding of the evolution of this remarkable radiation, and also to refine our understanding of potential responses to habitat degradation and environmental change.
Insights into the ecology and biogeography of Amborella trichopoda: intraspecific genetic differentiation in New Caledonia
Jérôme Munzinger, Institut de Recherche pour le Développement
Valérie Poncet, Institut de Recherche pour le Développement
François Munoz, Université Montpellier II
Yohan Pillon, University of Hawai’i
Céline Gomez, Institut de Recherche pour le Développement
Marie Couderc, Institut de Recherche pour le Développement
Christine Tranchant-Dubreuil, Institut de Recherche pour le Développement
Serge Hamon, Institut de Recherche pour le Développement
Alexandre de Kochko, Institut de Recherche pour le Développement
Amborella trichopoda is endemic to New Caledonia and is the sole living member of a lineage that may be over 200 Million years old, long before the re-emergence of the present archipelago. Amborella has been deeply studied, however, there is no survey on the intraspecific genetic variation. Thus, we studied Amborella genetic (18 populations) and ecological variation throughout its natural distribution, using 10 microsatellite loci. Adjacent populations from the same locality but at different altitude appeared genetically similar. On the opposite, we found significant differentiation between any pair of locations, and four main well-differentiated, geographically distinct genetic groups were inferred using the Bayesian clustering algorithm in Structure software. To assess and understand the spatial distribution of genetic diversity in relation with habitat suitability, we modeled the ecological niche of Amborella using Maxent. The model based on climatic and environmental conditions fitted well the distribution of the species, except in the northern part. The southern Nakada genetic group appears quite different. For the other groups, we found the cumulated habitat distances to be correlated with geographic distances, so that there was no barrier in suitable habitat that could explain the genetic differentiation of the groups. This suggests other biogeographic constraints, while the genetic differentiation within each group clearly follows the isolation by distance model. Thus, genetic diversity was highly structured both between sites and between genetic groups. This pattern indicates a genetic signature of long period events, which might be associated with a species with long-lived and locally dispersed individuals.
Interannual fire-climate teleconnections across the southern temperate latitudes.
Andres Holz, University of Tasmania
James Risbey, CSIRO Marine and Atmospheric Research, Tasmania, Australia
Thomas T. Veblen, University of Colorado, USA
Sam Wood, University of Tasmania
David Bowman, University of Tasmania
Understanding how patterns of wildfire activity are shaped by atmospheric conditions conducive to burning is a high research priority in the context of global environmental change. Although climate variations are often understood (and modeled) as random fluctuations about a constant or gradually changing mean state, wildfire activity responds to interannual drought (or antecedent high humidity in xeric ecosystems). In this paper, we relate interannual variability in large-scale climate drivers to annual area burned (AAB) using documentary fire records from Tasmania, South Africa, southern South America, and New Zealand. We identify large regions with common temporal variability in annual area burned, relate this variability to local interannual climate variability and in turn to modes of the major tropical and extra-tropical climate drivers of the southern hemisphere (i.e. El Niño Southern Oscillation (ENSO), the Southern Annular Mode (SAM), and Indian Ocean Diapole (IOD)). Our findings reveal the relative importance (i.e. proportions of area burned in each region) that are associated with coincident drought vs. antecedent wet conditions, implying mechanisms that enhance fire activity fuel desiccation and fine-fuel build-up, respectively. These results inform both long-term studies of paleo-fire and climate variability as well as short-term (satellite-era) spatial fire analyses of climate-fire relationship.
Invasive conifers in South America: Moving from assessment to management.
Anibal Pauchard, Universidad de Concepcion - Institute of Ecology and Biodiversity
Martín Nuñez, Lab. Ecotono, Inibioma, Conicet
Rafael D. Zenni, Department of Ecology and Evolutionary Biology, The University of Tennessee.
Non-native conifers have been widely planted as forestry species in South America and some are invading, causing ecological and social impacts. We review the state of conifer invasions in South America, and highlight initial management efforts to control this threat. In Chile, temperate and mediterranean ecosystems are being invaded by non-native conifers (e.g., Pinus radiata, Pinus contorta, and Pseudotsuga mensiezii). Some invasions occur in highly sensitive systems such as Araucaria araucana forests. In response to new recommendations from certification programs such as the FSC, companies are now initiating control efforts in conjunction with research for the restoration of invaded areas. The Chilean Forest Service is also controlling conifers in public protected areas. In the Patagonia of Argentina, Pinus contorta invades open areas (savannas, shrubland and steppe) and Pseudotsuga mensiezii invades Nothofagus and Autrocedrus forests. In grassland of the pampa’s region, Pinus halepensis is encroaching into the native vegetation. There is very limited control of the invasions outside of national parks, and most forestry companies do not manage for invasions. In Brazil, many conifer species are planted for forestry and horticulture. Among the species spreading outside plantations Pinus taeda and Pinus elliottii are the most notable, although Pinus glabra and Pinus patula spread into natural habitats. Pines invade grasslands, savannas, degraded habitats, and secondary Araucaria moist forests. Some States have started management programs in protected areas and forestry companies are also controlling the spread of pines. AP funded by Fondecyt 1100792, ICM P05-002 and CONICYT PFB-23.
Kiwi Curare: Miocene Menispermaceae in New Zealand
John G Conran, University of Adelaide
Daphne E Lee, Department of Geology, University of Otago
Jennifer M Bannister, Department of Botany, University of Otago
The pantropical plant family Menispermaceae (Moonseeds) are well represented in the fossil record of many countries, often as distinctive, ornately-sculptured endocarps. Here we report the presence in the earliest Miocene Foulden Maar deposit of endocarps assignable to the extant south-east Asian, Australian and Pacific genus Hypserpa. The fossil endocarps are compared to living Menispermaceae, as well as with leaf impressions from the site and dispersed cuticles reported previously from the Miocene of New Zealand and represent the first macrofossils of the family assignable to genus. The biogeographic and paleoecological implications of the presence of a tropical to subtropical vine in the early Miocene of southern New Zealand are discussed.
Land ahoy! An Oligocene shoreline on Otago Schist and implications for the total submergence of Zealandia
James Scott, Department of Geology, University of Otago
Ewan Fordyce, Department of Geology, University of Otago
Daphne Lee, Department of Geology, University of Otago
Late Oligocene (Duntroonian/Waitakian) impure limestone at Kokonga (Central Otago, New Zealand) is a shallow water rocky shore facies that, in contrast to previous assumptions, unequivocally demonstrates that a marine shoreline was present in the Otago Schist near the time of maximum Cenozoic sea-level transgression across Zealandia. Although the adjacent land may have been subsequently inundated by the Pacific Ocean/Tasman Sea in the Late Oligocene-Early Miocene, the Otago Schist island would have provided a haven for endemic flora and fauna. The limestone contains shallow water indicators such as coralline algae, echinoderms, bryozoans, corals, and a foraminiferal assemblage composed almost entirely of shallow benthic species including warm-water Amphistegina. Angular and poorly sorted schist clasts within the limestone, often adjacent to unbroken fossils and algal mats, indicate that deposition occurred as the sea lapped up against an eroding schist coastline. Confirmation of an Oligocene shoreline in Central Otago suggests that caution must be applied to the theory that Zealandia was totally submerged and planed flat in the Oligocene and then re-colonised by completely new fauna and flora in the Early Miocene.
Last Glacial and Holocene westerly wind changes on sub-Antarctic Macquarie Island
Krystyna M. Saunders, Institute of Geography and Oeschger Centre for Climate Change Research, University of Bern
Dominic A. Hodgson, British Antarctic Survey
Martin Grosjean, Institute of Geography and Oeschger Centre for Climate Change Research, University of Bern
The mid- to high-latitudes of the Southern Hemisphere are dominated by the westerly winds. These are important because changes in their strength determine precipitation and temperature regimes. However, little is known about their past strength, or spatial and temporal variability. Sub-Antarctic islands are the only landmasses between Antarctica, South America, Africa and Australia where terrestrial climate and ecosystem records are available, making them crucial locations for linking southern mid- and high-latitude regions. However, few long-term climate and ecosystem records exist. This project aims to address these gaps by utilising lake sediment cores from Macquarie Island (54°30’S, 159°57’E) to reconstruct changes in wind strength and identify ecosystem shifts over time. A marked west-east gradient in salinity exists across the island as saline ions are delivered by wind-derived sea spray. A diatom-salinity model was established and applied to a sediment core dated using 210Pb and 14C. This was used to infer past lake water salinity and consequently, wind strength (i.e. higher salinity implies stronger winds). The base of the core was ca. 27,000 cal. years old. Windier conditions prevailed from ca. 27,000-19,000 cal. years BP, before abruptly decreasing at the end of the Last Glacial period. The winds were generally less strong during the Holocene apart from ca. 6000 cal. years BP. Comparisons to other studies in the sub-Antarctic region and mid- and high-latitudes of the Southern Hemisphere are made to investigate broader-scale changes in wind strength and ecological responses to changing climatic conditions.
Last Glacial Cycle Environments in northern New Zealand: rapid climate events recorded in Pukaki maar lake, Auckland City
Paul Augustinus, School of Environment, The University of Auckland, Auckland 1142, New Zealand
Donna D'Costa, Auckland University of Technology, Auckland, New Zealand
Anna Sandiford, The Forensic Group Ltd, PO Box 17-317 Greenlane, Auckland 1546, New Zealand
Phil Shane, School of Environment, The University of Auckland, Auckland 1142, New Zealand
Janet Wilmshurst, Landcare Research, Lincoln, New Zealand
High-resolution ice core paleoclimate records from Antarctica demonstrate that numerous rapid climate fluctuations during the last glacial cycle (LGC). The EPICA Dronning Maud Land (EDML) oxygen isotope record displays brief warm episodes of ca. 2.5 ka duration during the last glacial cycle termed Antarctic Isotope Maxima (AIMs) that immediately preceded the Dansgaard-Oeschger events in the NGRIP record and are coeval with Heinrich Events. Marine cores from the southwest Pacific and Southern Ocean show evidence for some of these rapid southern polar warming events, although the well-dated high-resolution Southern Hemisphere terrestrial paleoclimate records spanning the LGC with which to ascertain their possible terrestrial mid-latitude manifestation are scarce. Here we present high-resolution geochemical and pollen records from Pukaki maar lake sediments from northern New Zealand underpinned by tephrochronology and AMS 14C dating that indicate that many of the AIM events observed in the Pukaki multi-proxy paleonvironmental record correlate with those preserved in the EDML paleoclimate record. This suggests that there was a closely coupled atmosphere-ocean circulation system in the Southern Hemisphere during the AIM warm events of the last glacial cycle that exerted its influence as least as far as the southwest Pacific mid-latitudes. Pollen-inferred mean annual temperatures in northern New Zealand increased by as much as 6° C during the AIM warm events, and together, the multi-proxy dataset from the terrestial and marine records provide important clues towards the nature of their high latitude Southern Hemisphere polar drivers.
Late Cretaceous to early Paleogene Biotas from an Austral Polar Greenhouse: new discoveries from the Chatham Islands and South-eastern Australia
Jeffrey Stilwell, Monash University
Chris Mays, Monash University
David Cantrill, Royal Botanic Gardens and National Herbarium of Victoria
Daniel Bickel, Australian Museum
Ann Quinney, Monash University
Julia Clarke, University of Texas-Austin
Paul Nascimbene, American Museum of Natural History
Chris Consoli, Geoscience Australia
Chris Hollis, GNS Science
Marine and terrestrial successions on the Chatham Islands—the only emergent rocks along the Chatham Rise—provide an important window into the geology and paleontology of eastern Zealandia. Recent fieldwork in the terrestrial to paralic Tupuangi Formation and marine Takatika Grit have resulted in significant new collections of Late Cretaceous to earliest Paleogene macro- and microfossils of plants and animals, including: diverse assemblages of gymnosperms, ferns and angiosperms and associated in-situ trees, abundant cones, fruiting bodies and seeds, leaf compressions, spores and pollen; the first record of insects (rare coleopterans); avian and non-avian dinosaurs; marine reptiles; fish; sponges; and Mollusca (bivalves, gastropods and cephalopods). The Chathams are emerging as an integral site for understanding the evolution of Zealandian biotas.
The May 2011 major discovery of the oldest fossiliferous amber deposit from Australia, and all of Southern Gondwana, provides a unique opportunity to study the only recorded terrestrial biotas of this age on the continent. The resin is present in petroleum cores in the Otway Basin from ~2.5 km depth, spanning some 250 m of section. Although in the early stages of investigation, the newly recorded fossils dated as late Turonian (~90 Ma) in age will be extracted virtually in 3D, employing Synchrotron and the X-ray ultramicroscope imaging techniques, to capture the finest of morphologic details from this major find. These biotas will be the first identified Mesozoic terrestrial organisms of this age living in habitats in and close to the resin-producing forests in a south polar ‘super-greenhouse’ setting.
Late Holocene fire history and the impact on vegetation in northern Tasmania
Hahjung Chin, Australian National University
Simon Haberle, Australian National University
Catastrophic disturbance events such as fires have had strong influence on the development and maintenance of mosaic landscape in Tasmania. The mechanism in which fires interact with other variables, for instance, vegetation, soil conditions and climate, has therefore been a research focus for years. Yet case studies involving local vegetation responses to fire events outside well-studied southwestern Tasmania are relatively infrequent. Reconstructing post-fire dynamics on palaeoenvironments in this region is therefore key to expanding our understanding of processes in which this mosaic landscape has originated. We present two records exhibiting fire and vegetation history of late Holocene in northern Tasmania. One is from Lake Wilks situated at 1060 m altitude, surrounded by Eucalyptus-dominated forest to the east and Athrotaxis-dominated woodland to the west. The other is from a small pool located on the slope of upper Mersey Valley at 270 m altitude, where mosaic of lowland sclerophyll forest and treeless heathland dominate the landscape. Through the analysis of pollen and charcoal particles from these sediment records, the impact of fire on vegetation in two different settings is examined and compared. Also, the ecosystem state shifts as well as the stability and resilience of these mosaic landscapes are discussed in light of the results obtained from this study.
Late Quaternary refugia, extinctions and extra-terrestrial impacts: lessons from the Atacama
Claudio Latorre, Dept. Ecología, Pontificia Universidad Católica de Chile; Institute of Ecology & Biodiversity, Santiago, Chile
The Atacama is a vast, rocky, hyperarid desert nestled between the Andes to the east and the Pacific Ocean to the west. Despite an extended history of hyperaridity (since the Mio-Pliocene), global climate fluctuations during the late Quaternary have been well-documented in the Atacama, both within and on the margins of the hyperarid core (where annual rainfall <10 mm). Major pluvial events occurred during the late Pleistocene (aka the Central Andean Pluvial Event, CAPE 17.5-10 ka) as well as during the Holocene (7.6-6.6 ka and 1.5-0.8 ka). These had major impacts on the distribution of the flora, fauna and consequences even for the peopling of this region of the world. During the CAPE, increased rainfall (up to five times greater than today) provoked downslope migrations and invasions into the hyperarid core, increased fluvial discharge, and elevated groundwater tables which in turn created riparian corridors and wetlands that facilitated dispersal across regions of the hyperarid core. Conversely, as pluvial events abruptly ended, wetter species became spatially restricted, in some cases to highly endemic regions on the Altiplano or to local oases/perennial rivers. These “pluvial relicts” can be found where plants have managed to subsist under favorable microclimates. Paleoecological evidence reveals that some species, however, did not survive the Holocene and are now locally extinct. Given the abundance of paleowetlands, we tested for evidence of an extraterrestrial impact proposed to have occurred at the end of the Pleistocene (12.9 ka) but the abundance of markers found requires an alternative explanation.
Leaf fossils and palynofloras reveal a subtropical Early Eocene South Canterbury, New Zealand
Elizabeth M. Kennedy, GNS Science
J. Ian Raine, GNS Science
Erica M. Crouch, GNS Science
Hugh E.G. Morgans, GNS Science
Denise K. Kulhanek, GNS Science
Broken River Formation coal measures crop out in Otaio River near Timaru, South Canterbury. Palynology, leaf morphology-based paleoclimate analysis (CLAMP and Leaf Margin Analysis – LMA), carbon isotopes, sedimentology, foraminifera and nannofossil analysis have been employed to characterize the exposures. A shell bed ~70 m above the base of the Formation marks the end of terrestrial/estuarine deposition and development of a fully marine setting.
Miospores and dinoflagellate cysts indicate that the coal measures are earliest Eocene (New Zealand PM3b/MH1 miospore zones, Waipawan to early Mangaorapan). Mesothermal pollen elements include Spinizonocolpites prominatus (Nypa), Malvacipollis subtilis and Cupaneidites species. Sparse dinoflagellate cysts and sand-filled burrows in leaf-bearing carbonaceous mudstones indicate probable estuarine deposition - the dinoflagellate cyst Apectodinium suggests that the leaves were deposited during one of the Apectodinium acmes that occurred during, and soon after, the PETM.
The predominantly angiosperm leaf assemblage also includes a few podocarp, fern and probable araucarian leaves. Morphological analysis of broadleaved angiosperms has yielded mean annual temperature estimates of 20.01 ± 2.36°C (CLAMP - Physg3brcAZ calibration; ± 2 stdev.), 21.64 ± 3.39°C (LMA – south east Asia calibration; ± Sampling Error) and 15.97 ± 2.99°C (LMA - Australian calibration; ± Sampling Error). Other estimates from CLAMP indicate mild winter temperatures (CMMT range: 7.25 – 14.77°C, 2 stdev.), warm summer temperatures (WMMT range: 25.45 – 31.77°C, 2 stdev.) and a long growing season. A humid subtropical climate similar to that of modern coastal Yakushima, Japan existed in Early Eocene South Canterbury.
Lipid-based paleotemperature reconstructions for the late Quaternary in southern New Zealand, part 1: development of methodology
Klaus-G. Zink, GNS Science, Lower Hutt, New Zealand
Marcus Vandergoes, GNS Science, Lower Hutt, New Zealand; Climate Change Institute, University of Maine, Orono, USA
Rewi Newnham, School of Geography, Environment and Earth Sciences, Victoria University of Wellington, Wellington, New Zealand
Thorsten Bauersachs, Institute of Geoscience, University of Kiel, Germany
Lorenz Schwark, Institute of Geoscience, University of Kiel, Germany, firstname.lastname@example.org; WA-OIGC, Curtin University, Perth, Australia
Terrestrial bacteria and archaea reflect environmental growth conditions, in particular temperature, by modification of their cell membrane lipids. The lipid-temperature relationships currently have been used to reconstruct paleotemperature from lake sediments and soils.
We investigated 30 lakes in the South Island of New Zealand, located at different altitudes comprising a range of mean annual air temperature (MAAT) from 1.5–13°C. Bacterial (branched Glycerol-Dialkyl-Glycerol-Tetraethers – brGDGTs) and archaeal lipids (isoprenoidal Glycerol-Dialkyl-Glycerol-Tetraethers – isoGDGTs) occur in the lake sediments, waters and catchments soils. Temperature calibrations via ratios (MBT and CBT) derived from brGDGT distributions are improved from a previous study. We address the potential origin of the brGDGT-synthesizing bacteria, with respect to different communities residing in soil and lake habitats.
Separate brGDGT distributions for lakes and soils require deconvoluting the relative proportions of allochthonous/autochtonous brGDGTs in lake sediments. MBT values of sediments are lower than those of corresponding soils, giving a better correlation with MAAT. Concentrations of isoGDGT are significantly lower than brGDGTs but still reflected systematic variations with temperature.
Remote loggers installed in and around several lakes provide a detailed annual record of local temperature which, at exposed lakes, significantly deviates from a predicted general temperature model. The observed higher lake water temperatures correspond with higher MBT values, demonstrating the need for precise local calibration and verification of molecular paleothermometers.
We conclude that GDGTs in contemporary NZ lake sediments reflect predominantly an autochthonous bacterial and archaeal input suitable for reconstructing paleotemperatures in limnic records.
Lipid-based paleotemperature reconstructions for the late Quaternary in southern New Zealand, part 2: preliminary applications
Marcus Vandergoes, GNS Science, Lower Hutt, New Zealand
Klaus-G. Zink, GNS Science, Lower Hutt, New Zealand
Rewi Newnham, School of Geography, Environment and Earth Sciences, Victoria University of Wellington, Wellington, New Zealand
Janet Wilmshurst, Landcare Research, Lincoln, New Zealand
Ann Dieffenbacher-Krall, Climate Change Institute, University of Maine, Orono, USA
Lorenz Schwark, Institute of Geoscience, University of Kiel, Germany
Recently developed New Zealand climate reconstruction models, based on biological indicators including pollen and insect remains preserved in lake sediment have contributed significantly to the range of techniques available to provide quantitative reconstructions of past climate. These records are essential for defining the temporal and spatial magnitudes of paleoclimate variability in the Southern Hemisphere.
Lipid biomarkers from bacteria (branched isoalkyl Glycerol Dialkyl Glycerol Tetraethers: GDGTs) offer a new promising method for determining precise paleotemperature reconstructions in freshwater systems including adjacent soil environments. The application of bacterial lipid indices such as MBT (methylation ratio of branched tetraethers) and CBT (cyclisation ratio of branched tetraethers) has proven reliable for estimating air temperature from terrestrial environments. Our preliminary research using MBT and CBT ratios has provided robust estimates of temperature in modern and paleo New Zealand lakes (Zink et al., 2010) that are independently corroborated by modern temperature values and established reconstruction techniques (chironomid analysis).
We present progress on applying a newly developed lipid-based temperature inference model to two climatically sensitive sites in southern New Zealand for the Last Glacial Maximum and Late glacial time periods. We discuss the resulting paleotemperature reconstructions in light of assessing the relationship between lipid, chironomid and pollen proxies and deriving combined multi-proxy temperature reconstructions for past environmental change.
Little bits and pieces: “A sub-‐alpine lacustrine plant macrofossil record from south-‐central Tasmania”
GISELLE A. ASTORGA, School of Plant Science, University of Tasmania
GREGORY J. JORDAN, School of Plant Science, University of Tasmania
TIMOTHY J. BRODRIBB, School of Plant Science, University of Tasmania
Plant macrofossils in lake sediments are being increasingly used to refine our
understanding of past vegetation history, ecological processes and related climate
conditions in late Quaternary paleoreconstructions. Macrofossils are often preserved
alongside fossil pollen providing additional information on the local paleovegetation.
In particular, macrofossil studies may identify species not represented in the pollen
record and contribute to understanding the provenance of wind-dispersed pollen
types. Consequently, plant macrofossils have the potential to record extinctions of
species or ecotypes, and provide environmental evidence not provided by fossil
We are studying a core extracted from Lake Dobson, Mt. Field National Park, in
south-central Tasmania. The core is rich in phytodebris and provides a continuous
sedimentary sequence extending back ~16,000 years BP. Plant material from this core
is being used to deduce the evolution of vegetation in this key midlatitude temperate
area. This information is needed to understand the timing, direction and frequency of
climatic oscillations that occurred during an important period of environmental
change: the transition from the end of the last glaciation into the Holocene and
subsequently to present day conditions. Additionally, no macrofossil studies have
examined this time period in Australia.
In this study we address the following questions: (1) does the macrofossil record
provide concordant evidence with our current understanding of postglacial vegetation
evolution in south-central Tasmania, in particular the timing and direction of
ecological responses of vegetation to climate change, and (2) is there evidence for
renewed cooling events having occurred after the onset of the deglaciation?
Living on the Edge: the Distribution and Phylogenetics of Nematodes in Victoria Land, Antarctica
David A. Wharton, Department of Zoology, University of Otago
Mélianie R. Raymond, Department of Zoology, University of Otago
Craig J. Marshall, Department of Biochemistry, University of Otago
Nematodes living in the rare ice-free terrestrial habitats of continental Antarctica inhabit one of the most extreme environments on earth. Their low species diversity and the abiotic stresses that limit their growth mean that they may be especially sensitive to climate change. We have studied the distribution of nematodes along the Victoria Land coast, as part of Antarctica New Zealand’s Latitudinal Gradient Project (LGP). In this paper we report the analysis of data from the first two LGP sites; Cape Hallett and Gondwana Station and some preliminary analysis from Granite Harbour and Darwin Glacier.
Soil geochemistry, especially salinity, has a strong impact on nematode distributions. The distinct distribution patterns of the four species found indicate different niches. Panagrolaimus davidi is the only nematode that can survive within penguin rookeries, where salinity is high but bacterial food plentiful. Scottnema lindsayae was found across the greatest range of habitats, including the driest sites and largest salinity range. Plectus murrayi was found in the wettest sites, with high organic content and low salinity. Eudorylaimus sp. was found at low densities and with other nematodes. This indicates a dependence on prey availability, an example of a biotic interaction structuring even these simplest communities.
Phylogenetic analysis generally confirmed morphological identifications. A culture stain of P. davidi isolated from Antarctica some years ago has, however, been shown to be a different species to the field strain of P. davidi.
Loss of 60 million years of dragonfly evolution narrowly averted by controlling invasive alien trees
Michael J Samways, Stellenbosch University, South Africa
This current mass extinction crisis risks a quarter of all insect species, including dragonflies. Their charisma means they are iconic, and can represent many other components of biodiversity as well as receiving enthusiastic support from the public. With many freshwater systems being threatened, one tenth of dragonfly species are also threatened, especially narrow-range specialists. Yet dragonflies can remarkably positively responsive to restored conditions. Considering all these threats and responses of dragonflies, we are able to instigate conservation strategies at the landscape scale, with an overlay of specific species conservation. Here, I explore the value of this approach. While it is important firstly to conserve natural areas the aim then is to restore conditions around these core areas, as dragonflies, even rare endemic species, tend to be ready colonists of suitable habitat conditions. In South Africa, rare endemic species can recover remarkably well once the key threat of invasive alien trees (which shade out their habitat) are removed. Recent DNA work has shown that some of these rare endemics diverged ±60 million years ago. Yet, in the geological blink of an eyelid, they have been pushed to the brink of extinction by alien invasive trees in particular. When these large-scale approaches are taken, dragonflies act as surrogates for other biodiversity, emphasizing how dragonflies can be mainstreamed into global conservation strategies.
Lost at sea? The biology of kelp rafting in the southern hemisphere
Martin Thiel, Universidad Catolica del Norte, Coquimbo, Chile
Molecular studies increasingly confirm biogeographic connections within the West Wind Drift (WWD). However, rafts must cross vast areas of open ocean and journeys are estimated to last between months and years. Our understanding of the rafting process is hampered by the little we know about the biology of floating kelps and the factors determining their survival at sea. At the sea surface, kelp rafts are exposed to solar radiation, winds and waves, the surrounding water mass (temperature and nutrients), and a ragtag crowd of stowaways (grazers and epibionts). How does this affect the survival of kelps and travellers during these long-distance journeys? Experimental studies indicate that floating kelps (giant kelp Macrocystis and bull kelp Durvillaea) can acclimate to the abiotic conditions prevailing in the WWD. I argue that the oceanographic conditions in the southern ocean prevent the risk of nutrient limitation for floating kelps. Accordingly, present data suggest that kelp growth exceeds consumption at commonly observed grazer densities. Epibionts (stalked barnacles and bryozoans) abundantly settle on giant kelp possibly suppressing its survival at the sea surface, while bull kelp appears to be less susceptible to epibiont colonization. Velocities of kelp rafts in the WWD have not been measured, but recent observations from the Chilean coast suggest that floating kelps occasionally travel much faster than previously assumed. In summary, available evidence indicates that kelp rafting still occurs at present conditions, but how changing climate affects these journeys can only be determined by in situ observations. Funding: FONDECYT 1100749.
Macroinvertebrate diversity in two adjacent catchments of the Chilean Patagonia: the role of local and regional environmental factors
Anna Astorga, Massey University & University of Oulu
Russell Death, Massey University
Josh Markham, Massey University
Marcelo Sanhueza, Centro de Investigación de Ecosistemas de la Patagonia
Pablo Marquet, P.Universidad Católica de Chile & IEB
Timo Muotka, University of Oulu
Chilean Patagonia comprises one of the most complex hydrological systems of South America and is an interesting region for examining the role that local environmental and regional factors play in regulating freshwater diversity. These systems were strongly modified by glacial activity of the Quaternary and more recently, 1930’s and 1940’s, by extensive fires. We studied taxonomic and functional macroinvertebrate diversity in two catchments in the Chilean Patagonia and the main local and landscape environmental variables related to diversity. Macroinvertebrate community similarity in both catchments was clearly influenced by the west-east precipitation gradient, but also productivity, forest types and recent land use history seem to play an important role differentiating the communities of these two neighboring catchments.
Managers’ attitudes and needs relative to future research assistance for wilding conifer management'
Keith Briden, Department of Conservation
Clayson Howell, Department of Conservation
The New Zealand Department of Conservation (DOC) has played a significant role in the development, execution and implementation of operational research into all aspects of wilding conifer management in New Zealand. In this paper we review 10 years of operational research. Past research has included; the development of new control methods, spread models, ecosystem services, fire, and succession ecology. Research results, along with proactive public awareness, have resulted in increased public and political support, which has resulted in more funding for control work. After several decades of increasing wilding conifer infestations, New Zealand is at a stage where we may be close to getting on top of wilding conifer spread. We are now able to address new incursions at an early stage and are able to make progress on some, but not all, of the large existing infestations. But, there remains much to do. We also present DOC’s views on research directions for the next 10 years. In particular we look forward to further refinement of techniques, greater understanding of long term costs and benefits of intervention, and refinement of prevention strategies. Obtaining greater community support and involvement will be a key direction of DOC. Better integration of science and public awareness will be required.
Marine subsidies to Subantarctic Terrestrial Environments
Colin D Meurk, Landcare Research NZ Ltd
Alexander J F Fergus, Fifty Degrees South Trust
Martin N Foggo, Rotorua
Mark Crompton, Hokitika
The importance of marine birds and mammals to insular terrestrial nutrient cycles has been well documented in warm-temperate NZ. Unexpected consequences of rebuilding this connection through mammalian pest control include reduced local plant species diversity due to increased bird disturbance and guano deposition and interference with burrowing prions by release of no-longer grazed boxthorn. We are testing these relationships on subantarctic Campbell Island, denizen of vast colonies of penguins, albatrosses, petrels, seals and sea-lions. Many of the inputs of marine-derived nutrients are applied in concentrated areas near the coast – on cliffs or in harbour wallows. However, some solitary nesting albatrosses are widely dispersed across upland grasslands and therefore one might expect a more generalised contribution to terrestrial nutrient pools. This to some extent compensates for the exponential decay of aerosol-derived soil nutrients away from exposed coasts shown in earlier work. The consequences of climate-driven changes to marine circulation and proximity of nutrient upwelling and fish stocks to seabird nesting islands, and over-fishing in southern oceans are likely to be drastic to the viability of marine birds and mammals and hence on terrestrial nutrient cycling and ecosystem dynamics.
Matching and mixing among the amphitropical floras of the Americas
Pablo C. Guerrero, Instituto de Ecologia y Biodiversidad
Laura Cussen, Stanford University
Gustavo Bizama, Instituto de Ecologia y Biodiversidad
Ramiro O. Bustamante, Instituto de Ecologia y Biodiversidad; Departamento de Ciencias Ecologicas, Universidad de Chile
Mary T.K. Arroyo, Instituto de Ecologia y Biodiversidad; Departamento de Ciencias Ecologicas, Universidad de Chile
Taxa with amphitropical distributions centered on western North America, and southern South America with similar climates, but absent at tropical latitudes, have long attracted the attention of plant biogeographers. Such disjunctions may occur within species or within lineages and can be considered in the context of niche conservatism whereby taxa colonize and spread into new areas (settler populations) having similar environmental characteristics as in the original distribution area (original populations). Here, we explore the extent to which four amphitropical herbaceous species (Sanicula graveolens, S. crassicaulis, Fragaria chiloensis and Hoffmannseggia glauca) and a subclade of Krameria have maintained their climatic niche after putative long-range dispersal between western North America and southern South America and vice-versa. Phylogenetic evidence indicates colonization from north to south in the case of S. graveolens, S. crassicaulis and F. chiloensis and from south to north in the case of H. glauca and Krameria. Detailed analyses of climatic variables show significant differences in climatic space occupied in the native and colonized areas. For species colonizing from north to south, although climatic niches are generally smaller in South America, expansion into new climatic space has occurred. For species colonizing from north to south, climatic niches in North America are larger and tend to incorporate significant climatic space not represented in South America. Results indicate that considerable niche expansion can occur following historical introduction involving a limited number of propagules.
Financed by: ICM P005-02 and PFB-23, Chile.
Measuring progress towards ecological restoration goals that seek environmental naturalness
Victoria Froude, Pacific Eco-Logic
Chris Richmond, Pacific Eco-Logic
The main New Zealand protected area and development control statutes contain implicit policy goals relating to protecting environmental naturalness or natural character. Effective implementation of and reporting on these goals has been hindered in a number of cases by a lack of methodology for measuring the various components of natural character, especially for coastal environments (both terrestrial & aquatic).
Methodology for measuring levels of natural character, and therefore monitoring progress towards environmental naturalness goals, has been developed and applied through district-scale mapping in several coastal regions. This methodology measures key parameters (specific to different coastal environment types) that contribute to natural character. These parameters are combined into subindices addressing primarily ecological naturalness, hydrological and geomorphological naturalness and freedom from human structures. These subindices are integrated through a natural character index which can be used to report overall state and changes in natural character.
Implemented appropriately, the methodology is sensitive to detecting relatively small changes in naturalness over time. As such it has potential for measuring progress towards environmental naturalness restoration goals. The concept of "present-potential natural state" in the methodology contributes to a framework for measuring and comparing progress in very different environment types. This concept also addresses the interplay between natural disturbance regimes and human-mediated impacts (including alien species).
Medieval megadroughts, how wide-spread were they? Evidence from the southern hemisphere extra-tropics.
Michael-Shawn Fletcher, The Australian National University; Institute of Ecology and Biodiversity, Chile.
Patricio I Moreno, University of Chile, Chile
Brent B Wolfe , Wilfrid Laurier University, Canada
Evidence is mounting that the medieval period (AD 900-1350) was characterised by significant global hydro-climatic variability, manifest as multi-decadal ‘megadroughts’ that have been variously linked to the El Niño-Southern Oscillation (ENSO) and/or the North Atlantic Oscillation (NAO). To date, most evidence for these megadroughts comes from tree-ring data and intensive dating of submerged tree-stumps at sites located in North America. Comparatively little to no evidence comes from the southern latitudes, especially Australia, and a question-mark hovers over how wide-spread these megadroughts were and to what degree the southern latitudes ‘felt’ the apparently global medieval hydro-climatic variability. A further point of conjecture is over which phase of ENSO prevailed through the medieval period, with marine based records pointing toward a persistent La Niña-like state and terrestrial based evidence suggesting an overall dominance of El Niño events. The southern extra-tropics lie within the ENSO climate domain and are a critical testing ground for whether these megadroughts were global events and for gaining an insight in to the potential climatic drivers through this period. In this lecture, I will present stable isotope, sedimentary charcoal and palaeoecological data I have gathered from the extra-tropics of Australia (Tasmania) and southern South America (Chile) that feed directly in to the debate over this contentious issue.
Mediterranean treelines: the hidden role of seasonal drought on the sink activity of trees
Frida Piper, Centro de Investigación en Ecosistemas de la Patagonia, Coyhaique, Chile. Instituto de Ecología y Biodiversidad, Universidad de Chile, Santiago de Chile.
Alex Fajardo, Centro de Investigación en Ecosistemas de la Patagonia, Coyhaique, Chile
Lohengrin Cavieres, Departamento de Botánica, Universidad de Concepción, Concepción, Chile. Instituto de Ecología y Biodiversidad, Universidad de Chile, Santiago de Chile.
Globally, alpine treelines are associated with a mean growing season isotherm of around 6.8 °C. The most plausible functional explanation given so far to account for this pattern is that carbon (C) demands by sink activity (meristems) are reduced proportionally more than C gains along the decreasing temperature gradient (elevation); this explanation has been coined as the growth limitation hypothesis (GLH). In strong support for the GLH, elevational increases in mobile carbon pools have been found for different treeline species across the world. Treelines in Mediterranean-type habitats, however, are a notorious exception, occurring at season isotherms higher than 6.8 °C; thus these treelines are found at lower elevations than expected. As an example, Nothofagus pumilio, which forms the treeline along the southern Andes, showed strong support for the GLH at temperate latitudes but weak support at Mediterranean locations. We propose here that in Mediterranean treelines seasonal drought may mediate in 1) lowering treeline elevation, and 2) thus reduced support for the GLH. Similar to low temperature, drought generally provokes more drastic reductions in growth than in carbon gain, leading to increments in mobile carbon. The combined effects of low temperature and drought in Mediterranean treelines likely imply stronger growth limitations than those caused by low temperatures alone. Also, as drought intensity often decreases with elevation, any trend in mobile carbon driven by low temperature effects might be blurred by drought effects. We present an approach to test the co-limitation by temperature and drought on tree growth at Mediterranean treelines.
Megaflora extinction in the Southern Hemisphere: Holocene fossil records from Polynesia
Matthew Prebble, The Australian National University, Canberra, Australia
Jean-Yves Meyer, Delegation de la Recherche de Tahiti, French Polynesia
Janet Wilmshurst, Manaaki Whenua, Landcare research, Lincoln, New Zealand
Nicholas Porch, Deakin University, Melbourne, Australia
From Late Quaternary pollen and macrofossil records from the Gondwanan continental landmasses, unlike mammals and birds, very few plant extinctions have been recognised since human colonisation. Fossil diverse palaeoecological archives from the high and remote islands of the Polynesian Triangle show a completely different story and provide the most compelling evidence for how numerous plant extinctions arise. From ten islands, local extinctions or extirpations of widespread taxa are abundant and biased towards ten families, mainly comprised of mesic forest trees. Endemic species extinctions are rare, but these may eventually be described from the large number of unidentified fossil types present. Forest clearance, agricultural expansion, fire, rat predation and weed invasion have all be implicated in these Holocene extinctions but other anthropogenic stressors have yet to be elucidated. High-resolution multiple fossil proxy records including diverse fossil invertebrate assemblages can now provide intriguing insights into many poorly understood ecological processes including the decline in pollinators and the invasion of herbivores. We examine species-specific responses of a number of plants which demonstrate different ecological drivers of extinction by highlighting the spatial and temporal variability of extirpation across different islands. We attempt to define the current state of extinction debt in Polynesia and conclude that island structure and the timing of invasive species introduction has a large bearing on where and when plants go extinct.
Mi-1 deglaciation characterised by abrupt short-term cooling events
Bethany Fox, Department of Geology, University of Otago,
Gary Wilson, Department of Geology, University of Otago, Department of Marine Science
Daphne Lee, Department of Geology, University of Otago,
It has long been known that a number of abrupt, short-lived (~1 ka) cooling events have interrupted the general warming trend since the Last Glacial Maximum. However, little is known about the existence or otherwise of similar events during the geological past. A laminated lacustrine diatomite from the South Island of New Zealand provides a very high-resolution climate record of the mid-latitudes of the Southern Hemisphere during the earliest Miocene and the deglaciation phase of the Mi-1 event. The diatomite consists of two major laminated facies, dark and light, punctuated by diatomaceous turbidites and slumps. Light laminated diatomite is characterised by high reflectance and low magnetic susceptibility, density, and organic carbon content. It is interpreted to represent warm, humid conditions with high lake levels and high diatom productivity. Dark laminated diatomite is characterised by low reflectance and high magnetic susceptibility, density, and organic carbon content. It is interpreted to represent cooler, drier periods with low lake levels and low diatom productivity. Four intervals of dark laminated diatomite are identified. Two are short-lived (~1 ka) with abrupt onsets. Two are longer (~5 ka) with more gradual onsets. By analogy with Holocene events, these cooler periods may be related to rapid changes in the cryosphere and ocean circulation. Such sudden reversals in a trend of longer-term warming may be characteristic of climate behaviour during long-term warming and deglaciation of polar ice-caps.
Micro-moths reveal ancient New-Zealand-New Caledonia links.
George Gibbs, School of Biological Sciences, Victoria University
A recent study of fig-wasp mutualism which reviewed 48 investigations into the origins and age of the New Caledonian biota, concluded that support for vicariant origins of any New Caledonian taxa is lacking. Studies which purport to show the presence of Gondwanan groups on the island are rejected on the grounds of circularity of reasoning. Although the geological interpretation implies the modern island of New Caledonia has been submerged between the Cretaceous and Late Eocene, emerging about 37 Ma – a date corroborated by the majority of fauna and flora phylogenetic studies – there are still some case studies that support a much earlier origin. Should they all be rejected because they do not conform with the majority view? A recent phylogenetic analysis of jaw-moths (Lepidoptera: Micropterigidae), the stem group of moths and butterflies, will be discussed. It draws attention to the now largely submerged continent of Zealandia by revealing the history of a lineage of cryptic, humid forest invertebrates restricted to this crustal block. However, despite the steady accumulation of case studies involving the remarkable New Caledonian biota, a plausible history of its biodiversity remains elusive. Are we nearly there, or do we still have a long way to go?
Microbial carbonates and shelly fauna of a Miocene Lake Manuherikia, Central Otago, New Zealand
Jon K. Lindqvist, Geology Department, University of Otago
Daphne Lee, Geology Department, University of Otago
Skeletal and microbial carbonates form a small part of the largely siliciclastic Manuherikia Group lacustrine succession exposed in the upper Manuherikia Valley, 120 km northwest of Dunedin. A low-diversity shelly fauna of unionid bivalves, gastropods and ostracods is preserved. Microbial carbonates comprise stromatolites, oncoids, ooid sands, and palustrine marl beds. Stromatolitic beds are found above transgressive surfaces. They include a pavement of linked low-relief columns, and discrete cushions. Bulbous heads formed by encrusting remanent silicified conglomerate (silcrete) clasts up to boulder size that locally littered an uplifted and onlapped schist lakeshore. Small upright mushroom-like forms encrusted ooid sand shoals. Kidney-shaped oncoids, and thinly-coated rock, bone and shell clasts were rolled about during growth. Growth surfaces of stromatolites and oncoids are nodular to smooth. Strongly developed internal laminae are composed of dark-light micritic couplets. Calcified cyanobacterial filaments and tufts attest to a microbial origin, and carbonate precipitation during photosynthesis of algal-bacterial films. Stromatolites growing on the margins of Lakes Thetis and Clifton (Western Australia), Walker Lake (Nevada) and Lake Tanganyika are compared with Manuherikia examples. These lakes are saturated with respect to calcite, with salinities of 10% to >100% seawater-equivalent. Concentrations of salinity-intolerant hyridellid bivalves in stratigraphic proximity to the New Zealand stromatolite beds indicate that lake water chemistry in the upper Manuherikia depocentre may have fluctuated between fresh and brackish in response to changes in river inflow, outflow, and evaporation.
MIOCENE MYSTACINIDS (CHIROPTERA: NOCTILIONOIDEA) INDICATE A LONG HISTORY OF ENDEMIC BATS ON INSULAR NEW ZEALAND
Suzanne J. Hand, University of New South Wales
University of Adelaide, Trevor H. Worthy
University of New South Wales, Michael Archer
University of Adelaide, Jennifer P. Worthy
Museum of New Zealand Te Papa Tongarewa, Alan J.D. Tennyson
Canterbury Museum, R. Paul Scofield
The bat family Mystacinidae is the only living mammalian family endemic to New Zealand. Its sole surviving member is the peculiar walking bat Mystacina tuberculata. A second New Zealand Mystacina species (M. robusta) is thought to have gone extinct circa 1967. The family’s distribution included Australia in at least the Oligo-Miocene. Mystacinidae belongs to the Gondwanan bat superfamily Noctilionoidea, extant species of which are otherwise known from central and South America, and Madagascar. New Zealand’s first pre-Pleistocene mystacinid fossils have been recovered from Early Miocene sediments of the Manuherikia Group near St Bathans, Central Otago. The St Bathans Fauna includes many birds, fish, lizards, frogs, a tuatara, crocodile and turtle, as well as fragments of a mouse-sized, non-volant archaic mammal. The St Bathans mystacinid fossils consist of isolated teeth and postcranial fragments which appear to represent two new species of similar size and functional morphology (dental and wing) to Quaternary mystacinids. These distinctive fossils demonstrate that mystacinids have been in New Zealand for at least 19-16 Ma which adds to the ever-growing list of iconic endemic vertebrate lineages present in Zealandia by the Early Miocene including leiopelmatid frogs, sphenodontids, acanthisittid wrens, adzebills, moas and kiwis.
Miocene terrestrial climate from floral proxies of Otago, New Zealand
Tammo Reichgelt, Department of Geology, University of Otago
Wyn A. Jones, Department of Botany, University of Otago
David T. Jones, Department of Botany, University of Otago
Elizabeth M. Kennedy, GNS Science
Dallas C. Mildenhall, GNS Science
Daphne E. Lee, Department of Geology, University of Otago
Physiognomic characteristics and nearest living relative climatic envelopes were analyzed for three floral assemblages to reconstruct terrestrial climatic variables for the Miocene of Otago. The assemblages analyzed were the Foulden Maar flora (~23Ma; earliest Miocene) and the Double Hill flora and Kaikorai Leaf Beds, both from within the Dunedin Volcanic Group (13-10Ma; late Middle Miocene).
Mean annual temperature estimates from Foulden Maar (~19⁰C) and Double Hill (~18⁰C) differed little, whereas the Kaikorai Leaf Beds yielded lower temperatures (~14.5⁰C), all conforming to a subtropical to warm temperate climate, compared to a cold-temperate 11⁰C of modern day Dunedin. This conforms with oceanic proxies for Antarctic Front development during the Miocene (Nelson and Cooke, 2001). The coldest month temperatures for Foulden Maar and Double Hill were very mild (~15⁰C), but were apparently quite low (~7⁰C) for Kaikorai. It is possible that climatic deterioration had already set in during deposition of the Kaikorai Leaf Beds, whereas Double Hill was deposited during the Miocene climatic optimum.
Precipitation rates in Otago throughout the Miocene were comparable to those of modern day subtropical islands that are strongly influenced by oceanic climate (~1500-2000mm); much higher than modern day Dunedin (~800mm). However, CLAMP analysis suggests seasonal precipitation differences of ~500-600mm for Miocene New Zealand, a feature expected in a continental monsoon-driven climate. It is possible that monsoonal systems were of higher importance in Miocene New Zealand, but the oceanic climate would still account for a steady annual moisture supply.
Mixing models and molecules for southern African amphibians: lessons from the last glacial maximum and into the future
John Measey, Nelson Mandela Metropolitan University
Clemens Schreiner, Zoologisches Forschungsmuseum Alexander Koenig
Dennis Rödder, Zoologisches Forschungsmuseum Alexander Koenig
Southern Africa has two distinct assemblages of amphibians which correspond to areas of summer and winter rainfall. Frogs in these regions are hypothesised to have greatly altered their range in response to Pleistocene climatic fluctuations; colder climates having increased the range of Cape frogs, while warmer climes are thought to have favoured the expansion of the tropical assemblage. Further, these changes in climate are thought to have brought about the distinctive Cape amphibian fauna. We test this hypothesis using Species Distribution Models based on presence data for 20 representative anuran taxa endemic in these faunal centres. We then use paleoclimatic models for 21 Kya to reconstruct hypothetical historical distributions. Our results suggest a relatively static fauna which agrees with existing phylogeographic studies of a subset of Cape frogs. In addition, we project our representative taxa into available future climate scenarios and assess whether current conservation strategies should change.
Molecular phylogeny and morphology of the Platyarthridae (Crustacea: Isopoda) with a focus on the Australian fauna
Mohammad Javidkar , Australian Centre for Evolutionary Biology and Biodiversity and School of Earth and Environmental Sciences, The University of Adelaide
Steven J. B. Cooper , Evolutionary Biology Unit (and Australian Centre for Evolutionary Biology and Biodiversity), South Australian Museum,
Stefano Taiti , Instituto per lo Studio delgi Ecosistemi, Consiglio Nazionale delle Ricerche
Rachael A. King , South Australian Museum
William F. Humphreys , Western Australian Museum
Andrew D. Austin , Australian Centre for Evolutionary Biology and Biodiversity and School of Earth and Environmental Sciences, The University of Adelaide
The family Platyarthridae with nine recognised genera has a worldwide geographic distribution. Although the genera share some common characters (i.e. modified scale-setae on dorsal part, two-jointed second antenna flagellum, absence of pleopodal lungs and inability to roll up), the monophyly of these genera is doubtful as the characters seem inadequate to characterize a phylogenetically solid group. In order to test the monophyly of Platyarthridae, representatives of the main genera were analysed using molecular and morphological approaches including data from a Scanning Electron Microscopy (SEM) study. The ingroup examined comprises Trichorhina spp., Niambia spp. (Australia, South America, Africa), T. anophthalma, Platyarthrus spp. (Europe), and species of non platyarthrid families including Armadillidae, Philosciidae, Stenoniscidae and Porcelliondae from Australia. Bayesian phylogenetic analysis of the group using two nuclear (SSU rRNA (~700bp), LSU rRNA (~900bp)) and one mitochondrial gene (Cytochrome C Oxidase I (~750bp)) strongly showed the Platyarthridae was not monophyletic but the group most likely comprises multiple families. The morphological analyses using SEM on different body parts including antennae, cephalothorax, and scale-setae support the molecular results suggesting the presence of three distinct families. The molecular findings also revealed that the occurrence of an undescribed species of Niambia in Australia is potentially by recent introduction from Africa. Further data and analyses are required to determine whether South American and Australian groups diverged following Gondwanan separation.
New insights into lost plant-animal linkages: palaeoecological evidence for past pollinators, seed dispersers, seed predators, and herbivores in NZ
Janet Wilmshurst, Landcare Research
Jamie Wood, Landcare Research
Techniques for extracting and dating information from fossils and sediment records have undergone a rapid transformation. New molecular, isotopic, and analytical methodologies are increasingly being used alongside traditional palaeoecological techniques to provide more detailed and dynamic reconstructions of past ecosystems. In this presentation I show how we have applied a combination of fossil and ancient DNA analyses to less commonly examined types of deposits such as coprolites (fossilised dung), nest deposits, cave sediments and buried flood deposits. Analyses of these ‘snap-shot’ archives provide direct evidence for former plant and animal interactions in New Zealand’s pre-human past. Included are examples of extinct or rare birds (e.g., moa and kakapo) and those of introduced mammals (e.g., pacific rat) and examining their roles as former herbivores, seed dispersalists, pollinators, or seed predators and how they may have influenced ecosystem function. I then consider these relationships in the context of trying to understand to what extent introduced mammals have replaced the function of extinct taxa; can palaeoecology help answer if they are surrogates or swindling imposters?
New lessons learned from old-field restoration in south-western Australia
Rachel Standish, The University of Western Australia
Michael P. Perring, The University of Western Australia
Richard J. Hobbs, The University of Western Australia
David Freudenberger, Greening Australia
Lauren Hallett, The University of Western Australia
Justin Jonson, Threshold Environmental
Kristin B. Hulvey, The University of Western Australia
Lori Lach, The University of Western Australia
Large-scale ecological restoration is an important component of humanity’s response to environmental change and land degradation. This effort is especially critical in south-western Australia where rapid clearing of vegetation for agriculture has resulted in widespread problems including soil acidity and secondary salinity. The emerging carbon market has the potential to drive ecological restoration in the region, particularly if additional ecosystem services such as biological diversity are valued along with carbon. In this talk, I will describe two projects that aim to understand how best to achieve these multiple outcomes through the restoration of diverse species assemblages to old-fields. The first project is part of Greening Australia’s visionary Gondwana Link venture whose ultimate aim is to join the woodlands of the semi-arid interior to the coastal scrub at the mouth of the Margaret River. I describe how science has meshed with practice at one of the restoration sites, Peniup Farm, to inform large-scale ecological restoration in the region. The second project, at Ridgefield Farm, aims to assess the trade-offs among the provision of multiple ecosystem services, also with carbon as a driver. I describe the initial results of this experiment including the contribution of ‘novel components’ (i.e., weeds) to service provision. I summarise the practical and scientific lessons we have learnt and how these might assist the restoration of degraded old-fields elsewhere in the southern hemisphere. I conclude with a philosophical perspective on restoring degraded landscapes in times of environmental change.
New Zealand High Country Land Reform
Ann Brower, Lincoln University
Until 1992, land on the eastern slopes of New Zealand’s South Island was owned by the Crown and leased for pastoral sheep grazing. This land in Crown pastoral leases comprised 20% of the South Island, or 10% of NZ’s landmass. Since 1992, the pastoral leaseholders have been able to enter negotiations with the Crown to split the leased land – land below 1000m is privatised, whilst land with conservation values (usually above 1000m) shifts into public conservation land.
The papers I will present use the theories of rents, bargaining, administrative politics, and public choice to examine financial outcomes from New Zealand land reform. Results are inconsistent with payments arising from a bargain in which both the Crown and lessee advocate to their full potential, and are instead consistent with the Crown backing down to lessees’ desires for a generous deal. This back‐down stems either from "bureaucratic coping," or from the addition of a bureaucratic middleman between the Crown principal and its negotiator subagent, exacerbating the principal‐agent problem.
New Zealand Peatland archives and the southern westerlies
Rewi Newnham, Victoria University of Wellington, NZ
Dan Charman, University of Exeter, UK
Matt Amesbury, University of Exeter, UK
Zoe Hazell, English Heritage, UK
Maarten Blaauw, Queens University of Belfast, UK
David Lowe, University of Waikato, NZ
Peatlands have more potential for determining past changes in precipitation than most other archives. In New Zealand (NZ), we are still scratching at the surface of this potential, despite a pressing need for more reliable information about past precipitation. This demand stems in part from growing interest in the history of the southern westerlies because here, and elsewhere across the southern temperate latitudes, past patterns of precipitation can provide strong insight into past atmospheric circulation.
This paper will discuss the application of two peatland proxies with potential for reconstructing paleoprecipitation in NZ. We present peat humification and macro-charcoal records from ombrogenous peat bogs in the Waikato region for the mid-to-late Holocene, a timeframe encompassing major postulated changes in the westerly winds and ENSO. Reconstructed palaeomoisture levels in the bogs fluctuate strongly at decadal-to-centennial scales throughout, but also shift towards wetter conditions overall from c.5-4 ka BP, with drier summers in the late Holocene, consistent with stronger westerly circulation.
We also discuss a new project aimed at developing a paleomoisture proxy based on stable isotope (δ18O, δ D and δ13C) composition of vascular peatland plants. We hypothesise that stable isotopes in the peat forming parts of the restiad rush Empodisma reflect spatial variation in the isotopic composition of precipitation during the growing season. We are testing this hypothesis by monitoring the annual cycle of isotopic content of rainfall at a Waikato peatland and by sampling near-surface restiad peat cellulose and bog water across a latitudinal transect of sites in NZ.
New Zealand treelines in the Southern Hemisphere context: An overview of patterns and processes
Brad Case, Lincoln University
Alpine treelines are conspicuous features of mountain systems worldwide and have interested ecologists for decades. This is largely because treelines provide an ideal natural setting for examining the interplay among tree physiological function, population dynamics, and abiotic variability across multiple spatial and temporal scales. In this talk, I provide an overview of some of the interesting features of New Zealand’s treelines, placed in the general context of Southern Hemisphere treelines, as well as other treelines globally. Treelines in New Zealand display an enormous degree of variability across the country and I examine past and recent research regarding the possible causes, particularly with respect to variability in the abiotic environment. I will present the results of my own nation-wide analysis of Nothofagus treeline patterns, based on an integration GIS-based datasets, novel spatial analysis methods, and atmospheric modelling. I will show how these patterns vary across multiple spatial scales, and to what extent they are influenced by the complex, overlapping influences of climate, geology, topography, and disturbance. Finally, the implications of this body of research for our understanding of how these treelines might respond to future climates will be discussed.
New Zealand Wilding Conifer Management Group - how successful?
Nick Ledgard, Retired Scion scientist
Thomas Paul, Scion, Rotorua
The NZ (initially South Island) Wilding Conifer Management Group was formed in 2006 to bring together stakeholders affected by wilding conifers. Over a year was needed to assemble the group, secure funding, and get agreement amongst members to a legal and binding Memorandum of Understanding. The Group currently has 15 members representing national Government departments and agencies, local territorial authorities, major forest companies, conservation groups and farmers. Its initial function was to oversee a 4-year Government-funded research programme focussing on inventorying wilding-affected areas, assessing spread risk, improving control options, and determining the impacts of control on vegetation successions. Research outputs have been presented in reports, published papers and a Newsletter, all of which are available on the Group’s website (www.wildingconifers.org.nz). Improving the awareness of wilding issues by local authorities, land owners/managers and the public has been a major objective, and to this end numerous media articles, public presentations and field workshops have been delivered, mainly in the South Island. One outcome has been the formation of local community groups which have wilding control as their major aim. Over the last 2 years, the Group has contributed to the preparation of a national wilding status report and endorsed the report’s recommendations. The Group has been successful in bringing together all those affected by wilding conifers, and as a result is likely to comprise the stakeholder forum needed for the preparation of a national wilding strategy.
Nothofagus betuloides tree-ring growth patterns and climate variability in postglacial landscapes of Santa Ines Island, southern Chile.
Juan-Carlos Aravena, Centro de Estudios del Cuaternario Fuego-Patagonia y Antártica (CEQUA) Conicyt Regional R07K1002, Punta Arenas, Chile.
Carla Henríquez-Velásquez, Centro de Estudios del Cuaternario Fuego-Patagonia y Antártica (CEQUA) Conicyt Regional R07K1002, Punta Arenas, Chile.
Rodrigo Pérez, Centro de Estudios del Cuaternario Fuego-Patagonia y Antártica (CEQUA) Conicyt Regional R07K1002, Punta Arenas, Chile.
Temperate Nothofagus spp forests from southern South America cover a wide latitudinal distribution range (35º to 56ºS). The current structure and composition of these forests in their southernmost area were highly determined by landscape changes due to Pleistocene glacial cycles. N. betuloides is the southernmost tree species in the world and one of the less used in dendroclimatic studies. Recent results however, show that this species has high sensitivity to climatic variations, mainly air temperature, and to global atmospheric circulation patterns, such as the Southern Annular Mode (SAM).
We sampled four new sites, Ale0, Ale2, Bea0 and Bea1 in Santa Ines Island (53°45’S, 72°37’W), all of them associated with old moraines near to Alejandro and Beatriz glaciers, and corresponding to late successional stages. We developed tree-ring width chronologies from each site following the standard dendrochronological procedures. The resulting chronology lengths range between 150 and more than 300 years. The sites Ale0, Ale2 and Bea0 showed a clear growth decrease for the last 50 years. This decreasing tree growth has also been found in chronologies developed in Navarino Island (54º58’S, 67°41’W), where a significant correlation between N. betuloides growth and SAM circulation pattern was demonstrated. Our results confirm these relationships and allowed us to investigate their spatial patterns through a network of N. betuloides tree-ring chronologies.
Acknowledgements: Fondecyt projects 1080320 and 1090135.
One conifer’s wall is another one's highway
Greg Jordan, University of Tasmania
Tim Brodribb, University of Tasmania
The conifers are perhaps the most striking example of a major group of plants showing a north-south divide. The distinction is mostly at the family level, indicating that it is somehow related to events in the Mesozoic. Podocarpaceae and Araucariaceae are essentially southern, Pinaceae, Taxaceae, Cephalotaxaceae and Sciadoptyaceae are essentially northern, and Cupressaceae are split into major southern and northern clades, plus some a suite of ancient lineages restricted to one or the other region. Although these groups have Gondwanan or Laurasian fossil records (according to their current distributions), there are reasons to believe that ecological determinism and evolutionary niche conservatism are important in explaining the north-south divide.
In this talk we investigate the climatic distributions of the northern and southern conifers. We show that the northern and southern conifers occupy strikingly different environmental spaces, even in the regions where the groups overlap. We also show that patterns of species richness and phylogenetic richness show differences that seem best explained by conservation of ancestral ecologies in most groups. Overall, ecological determinism seems to be a major player in differentiating these groups, and this determinism has deep historical roots. This concept questions the dichotomy between vicariance and ecological determinism in controlling distributions of organisms.
Operational research supporting wilding conifer management in New Zealand
Peter Raal, Department of Conservation, Otago Conservancy, PO Box 5244, Dunedin, New Zealand
Stefan Gous, SCION, Private Bag 3020, Rotorua, New Zealand
Control of wilding conifers in New Zealand is based on two activities, namely physical and chemical control methods.
Although effective, physical control can only be used where trees are accessible. Also, these methods are labour intensive.
If they work, chemical control methods are more cost effective and less labour intensive than physical control methods. For dense infestations or situations where trees are inaccessible chemical control is the only solution.
Numerous herbicide application trial studies on many different species of wilding conifers are being conducted throughout New Zealand. The methodologies include boring holes into the stem and injecting herbicide, cutting the trees down and poisoning the stump with herbicide, ground-based basal bark application of herbicide in oil, aerial spot spraying of herbicide in oil and boom spraying. These trials are being conducted as a collaborative venture between Scion and the Department of Conservation.
The ground-based bore-and-fill (very large trees), cut stump (where aesthetics of dead standing trees is an issue) and basal bark methodologies (smaller trees) and the aerial spot treatment method are designed to control sparse, isolated and/or scattered wilding conifers. These wildings are a major concern, as they increase the point of invasion once they seed. These methodologies provide a mechanism whereby these trees can be relatively quickly and cost-effectively controlled before they seed. The boom spraying trials are designed to control dense infestations of wilding conifers.
The preliminary results of all of these experiments and implications for the future management of wilding conifer infestation will be discussed.
Orbital pacing of New Zealand hydroclimate during the Early Miocene: Biomarker and compound-specific isotope records from the Foulden Maar diatomite
William J. D’Andrea, Lamont-Doherty Earth Observatory, Palisades, New York
Sara Donatich, 2Barnard College of Columbia University, New York, New York
Bethany Fox, Department of Geology, University of Otago
Daphne E. Lee, Department of Geology, University of Otago
During the Early Miocene, atmospheric CO2 levels were similar to today yet global temperatures were warmer and large, stable polar ice sheets had not yet developed. Examining the climate dynamics of Early Miocene Earth requires quantitative paleoclimate records from terrestrial archives. Foulden Maar (45.5 °S, 170.2 °E) is an annually resolved maar lake deposit on South Island, New Zealand dating from the Oligocene/Miocene boundary. Anoxia in the basin fostered the preservation of a ~100m thick, annually laminated diatomite (the base of which has been dated to 23 ± 0.2 Ma using 40Ar/39Ar dating), and allowed for superb preservation of organic materials, including leaves, flowers, fish skeletons and insects. Here we examine the biomarker record and the hydrogen isotope composition (D) of leaf waxes (n-alkanoic acids) preserved in Foulden Maar sediments over a ~100,000 year interval of the early Miocene. Leaf wax D reflects D of past environmental water and therefore allows hydroclimatic reconstruction at the site. Our record reveals large variations (up to 40 ‰) in leaf wax D at obliquity and precession timescales and affords quantitative estimates of orbitally forced hydrologic changes during the Early Miocene. Sedimentary terpenoids reflect the composition of paleovegetation at the site and represent an independent proxy to complement pollen analyses throughout the diatomite. Additional biomarker-based analyses (including 13C of leaf waxes) are currently underway, and up-to-date results will be presented.
Origins and evolution of plant diversity on the southern lands: new insights from large phylogenies
Richard Winkworth, UMR 6553 ECOBIO, CNRS – Université de Rennes 1
Françoise Hennion, UMR 6553 ECOBIO, CNRS – Université de Rennes 1
Steve Wagstaff, Landcare Research
Understanding the origins of contemporary plant biodiversity poses many challenges but also provides important insights into the potential responses of plant lineages and communities to future environmental change. In this context the southern floras represent a unique series of natural replicates within which to examine the evolutionary and ecological processes that are responsible for contemporary patterns. Molecular phylogenetic analyses for individual lineages have provided important insights into the origins and evolution of southern plant diversity. However, it is now possible to assemble and analyze sequence datasets with very broad taxonomic coverage. Such trees are providing new insights. This paper will present results from recent work that makes use of these approaches. This includes studies that examine the role of Antarctica in shaping the links between the southern floras and work that focuses on placing the sub-Antarctic island floras within a wider southern context. We present the key results and discuss their implications in terms of understanding the formation of current diversity patterns and the impacts of future environmental change.
Origins of restiad wetlands in New Zealand
Steven J. Wagstaff, Landcare Research
Beverley R. Clarkson, Landcare Research
Theoretical predictions suggest extinction plays an important role in the assembly of island floras. Competition for scarce resources excludes most new immigrants, and successful colonists are more likely to become established in a biome that resembled their origin. We investigated phylogenetic relationships among the five currently recognised species of Restionaceae in New Zealand and show that they are nested in three distinct Australian lineages. While microfossil evidence suggests Restionaceae were present in New Zealand during the Oligocene, the molecular-based estimates suggest Empodisma and Sporadanthus are recent colonists arriving in New Zealand during the late Pliocene. Apodasmia similis may be a more recent immigrant diverging during the Pleistocene. Floristic turnover is well documented in the New Zealand palaeoflora and may be an explanation for the disparity between fossil ages and molecular-based estimates. The extant species are geographically isolated or occupy distinct ecological niches. Though it also grows in freshwater marshes, A. similis is tolerant to saline conditions and is common in coastal marshes throughout New Zealand. On the Chatham Islands, A. similis dominates early-successional freshwater stages, but is replaced by Sporadanthus traversii in ombrotrophic bogs. Empodisma minus is widely distributed in Australia and New Zealand inhabiting freshwater bogs and fens in lowland areas, but ranges into the alpine. In raised bogs north of 38° S latitude in New Zealand, E. minus is replaced by the newly described species E. robustum. Empodisma robustum and Sporadanthus ferrugineus coexist, but exploit different root zones in bog environments and avoid competition through stratification.
Palaeoclimate and human occupation in arid South Australia
Philip Hughes, HEH Pty Ltd and the Australian National University
Marjorie Sullivan, HEH Pty Ltd and the Australian National University
A very large archaeological mitigation and research program in the stony and sandridge desert near Olympic Dam in arid south Australia has involved the recording of more than 16,000 open archaeological sites and the excavation of ~150 of those sites. Although most of the stone artefacts relate to mid-late Holocene occupation, deeper occupation layers have been identified in a few sites. Palaeoclimatic evidence, particularly from extensively expanded (megaplaya) Lakes Eyre and Frome and ostracod evidence from Lake Frome and the Murray River mouth, indicate there were wetter periods at about 19-17 ka and at around 13-14 ka, as well as during the early and mid Holocene. OSL dates which bracket stone artefact layers in sand dunes provide a record of dune surface stability, and ages for occupation layers that match the palaeoclimatic records, indicating that people moved into this desert area during prolonged wet periods but abandoned it during drier phases. It is likely the rainfall that affected the Olympic Dam desert and Lake Frome was from the south.
Paleochemotaxonomic investigation of Tertiary fossil resins from southern New Zealand by gas chromatography - mass spectrometry: preliminary results
N.G. Powell, Forensic & Industrial Science Ltd, PO Box 20103, Glen Eden, Auckland 0641, New Zealand
D.E. Lee, Department of Geology, University of Otago
U. Kaulfuss, Department of Geology, University of Otago
Amber and other fossil resins are widely distributed in the geological record. The chemistry of such materials can be investigated by instrumental analysis for comparative purposes and to shed light on their botanical origins. Fossil resin material is known from several southern New Zealand paralic and non marine units, including the Oligocene Pomahaka and Chatton formations, the late Oligocene–early Miocene Gore Lignite Measures, and the Miocene Manuherikia Group. We have investigated material from five Oligocene and Miocene localities in Otago and Southland by gas chromatography–mass spectrometry (GC MS). Most resins investigated have undergone minor diagenetic change, with several labile and volatile compounds preserved. Preliminary analytical investigation shows abietic acid and dehydroabietic acid are present in the specimens investigated, which together with other aspects of their chemistry suggests an Araucariacean origin. Extant Araucariacean genera (Wollemia, Araucaria and Agathis) are prodigious resin producers but their resins differ only slightly in their chemistry. Current paleochemotaxonomic methodology does not allow fossil resins to be linked to a particular genus and is hence of limited taxonomic utility. We are exploring possible analytical routes that might improve the specificity of paleochemotaxonomic methods for fossil resins. We are investigating the chemistry of modern Araucariacean resins by GC MS with a view to identifying stabile taxon specific biomarker compounds in Wollemia, Agathis and Araucaria. Elucidation of synthetic routes responsible for generating geoterpenoids in fossil resins from corresponding bioterpenoid precursors might enable us to ascertain taxonomic affinities of the resin-producing plants in the New Zealand fossil record.
Paleoclimate and paleoecology of the Early Miocene Foulden Maar, Central Otago
Tammo Reichgelt, Department of Geology, University of Otago
Jennifer M. Bannister, Department of Botany, University of Otago
John G. Conran, Deparment of Environmental Sciences, University of Adelaide
Elizabeth M. Kennedy, GNS Science
Dallas C. Mildenhall, GNS Science
Daphne E. Lee, Department of Geology, University of Otago
Well preserved micro- and macrofossils from the earliest Miocene Foulden Maar, Otago, New Zealand provide several proxies for reconstructing local and regional climate and ecology. Different methods were used to reconstruct paleoclimate, such as CLAMP analysis, the Bioclimatic Envelope Approach and Podocarp Leaf Size climate relations. These paleoclimatic proxies suggested relatively warm mean annual temperatures of 19-21⁰C and annual precipitation rates of 1500-2000mm. CLAMP analysis also suggested relatively large seasonal precipitation variation, which could be the effect of a greater monsoonal influence from the tropics. This climate is comparable to that of modern subtropical to warm temperate climatic settings such as at Lord Howe Island, Norfolk Island and southeastern Queensland.
Combined micro- and macrofloristic characteristics were used to reconstruct the local ecosystems. Modern representatives were investigated as to their dominant growth habit, level of canopy and their preferred ecological niche. A dense subtropical rainforest grew adjacent to the maar. There were probably three levels of canopy with Lauraceae dominating the top canopy and vines, such as Ripogonum, growing into the canopy. Ferns occurred as minor understorey contributors as well as epiphytes. The niche of the maar edge was probably filled by taxa requiring forest openings such as Euphorbiaceae, Celastraceae and Myrtaceae. Proteaceae and Podocarpaceae probably dominated the well-drained hillsides surrounding the maar and dominant Nothofagus pollen suggests the presence of hinterland beech forests.
Phylogenetic Trees and Tree Violets: Making sense of the Melicytus alpinus species complex
David A Orlovich, University of Otago
David J Lyttle, University of Otago
Paul L Guy, University of Otago
The shrubby species Melicytus alpinus is perhaps the most widespread of the eleven species of Melicytus that have been described from New Zealand. It is found in the North and South Islands and grows from sea level to altitudes of about 1700 metres. In view of its geographic and altitudinal distribution it is not surprising that there is considerable variation present within this complex species.
Genetic analysis of the nuclear ribosomal internal transcribed spacer (ITS) region, the chloroplast trnL–F intergenic spacer and endogenous pararetoviral reverse transcriptase fragment (EPRV RT) sequences of collections of small-leaved Melicytus species from East Otago indicates that there is considerable diversity present. Three distinct taxa were identified. One of these corresponds to Melicytus flexuosus. The remaining two most closely resemble Melicytus crassifolius and Melicytus alpinus respectively. Some collections originally identified as Melicytus flexuosus appear to be hybrids between this species and Melicytus alpinus sens. lat.
Phylogeny of Calceolaria L. (Calceolariaceae) - genes vs. morphology
Stephan Nylinder, Swedish Museum of Natural History, Stockholm, Sweden
Ulf Swenson, Swedish Museum of Natural History, Stockholm, Sweden
Bernard E. Pfeil, Department of Biological and Environmental Sciences, Gothenburg University, Sweden
Christine Ehrhart, Department of Biology, Ludwig-Maximilian University, Munich, Germany
Alicia N. Sersíc, 4Instituto Multidisciplinario de Biología Vegetal (IMBIV), Córdoba, Argentina
Andrea Cosacov, 4Instituto Multidisciplinario de Biología Vegetal (IMBIV), Córdoba, Argentina
Pamela Puppo, 5Plant Evolution Group, University of Porto, Portugal
Bengt Oxelman, Department of Biological and Environmental Sciences, Gothenburg University, Sweden
Calceolaria is a large plant genus of some 300 species almost exclusively restricted to the Andean mountain range in South America. Conspicuous yellow flowers with saccate upper and lower lips make them easily distinguishable, easy to spot and thus widely collected in all Andean countries. Revisions made by several taxonomists have yielded different infrageneric classifications, but the phylogenetic relationships are still largely unresolved, and the few available studies have indicated wide discrepancies between genetic data and morphology. We present here the first well-supported, large-scale molecular phylogeny of the genus based on 133 sampled species, three plasmids (atpB-rbcL spacer, trnL-F, and rps16) and one nuclear marker (ITS), analyzed with Bayesian inference in BEAST. The plasmid tree is well-supported while the nuclear tree is partly recovered with good support, but analyses of the two datasets recover incongruent topologies, none corresponding well with the previous infrageneric classifications. Some important life strategies are still tracked: (1) adaptation to low precipitation habitats by evolution of a more lower rosulate or cauline life form, and (2) the monophyly of widespread weedy annuals (sect. Calceolaria). We will also present a peculiar case of incongruence between plasmid and nuclear data for the morphologically very homogenous section Perfoliatae.
Pinus contorta as a model species for global research on invasive trees: insights from Patagonia.
Anibal Pauchard, Universidad de Concepcion - Institute of Ecology and Biodiversity
Martin Nuñez, Lab. Ecotono, Inibioma, Conicet
Barbara Langdon, Bioforest S.A.
Pinus contorta is one of the most invasive tree species in in temperate ecosystems. It has been reported invasive in Sweden, New Zealand, the US (outside its native range), Chile and Argentina. In this paper, we used our experience in Patagonia to highlight the opportunities for global research on P. contorta that could shed light into its basic ecology as well as to understand and manage tree invasions. We have studied Pinus contorta using observational and experimental approaches at multiple scales in Patagonia. We have found that Pinus contorta in open temperate environments invades all substrates from bare ground to cushion plants. It can reach higher elevations than the native Nothofagus treeline and expand into steppe environments previously treeless, therefore its potential impact on native ecosystems is notably high. The role of native and non-native fungi and other soil biota may be keys to succeed in these very harsh environments. Patagonia serves as a very interesting study area because, unlike other sites such as New Zealand, P. contorta has just recently became invasive and most of the invasions are constrained to areas closer to the initial plantations. Information from other areas where the invasion is already well established can be used to understand and prevent the spread of the invasion. Recently, a global network of scientists has been implemented to study the species globally and address relevant questions about the biology and ecological consequences of P. contorta invasion. AP funded by Fondecyt 1100792, ICM P05-002 and CONICYT PFB-23.
Plant breeding systems and pollinator availability in alpine ecosystems along the latitudinal gradient in the southern South American Andes
Mary T. K. Arroyo, Instituto de Ecología y Biodiversidad (IEB), Facultad de Ciencias, Universidad de Chile, Santiago, Chile
Ana María Humaña, Instituto de Ecología y Biodiversidad (IEB), Facultad de Ciencias, Universidad de Chile, Santiago, Chile
How plant species adapt to extreme conditions for pollination is a central question in alpine ecology. The autonomous selfing hypothesis posits that cold and variable weather conditions will select for self-compatibility and selfing in high elevation ecosystems. Two large experimental plant breeding system data sets for latitudes 33° S (central Chile) and 50° S (Patagonia) are now available for alpine plant species in the South American Andes. Here, in conjunction with flower visitation rate data, we examine latitudinal tendencies in plant breeding systems. Considering the dominant perennial herb life-form, both latitudes show a wide range of breeding systems, there being contingents of self-incompatible and partially self-compatible species habitually serviced by biotic pollinators, in addition to strongly autogamous species. Although there is a tendency toward more SC at 50° S, the frequencies of SC and SI species in the warm and sunny central Chilean alpine and the cold and windy Patagonian alpine are not significantly different despite wide community-level differences in flower visitation rates at the two latitudes. Earlier work suggested that prolonged flower longevity may compensate for low pollination rates, but it has never been clear whether the latter has been selected for under such circumstances. Experiments on Oxalis compacta in the central Chilean Andes reveal that potential flower longevity in natural populations is closely conditioned by ambient temperatures as it affects rate of flower development, there being no evidence of selection on flower longevity.
Research financed by Fondecyt Grant 1085013 and IEB grants ICM P005-002 and PFB-23, Chile
Polyploid evolution in New Zealand’s alpine buttercups – insights from high-throughput sequencing and fine-scale climate measurements.
Matthias Becker, Massey University Manawatu
Richard J. Carter, University of Zurich
Nicole Gruenheit, University of Manchester
Oliver Deusch, Waltham Centre for Pet Nutrition
Carlos A. Lehnebach, Te Papa
Patrisha A. McLenachan, Massey University Manawatu
David Havell, DOC Auckland Conservancy
Olga Kardailsky, Otago University
Claudia Voelckel, Massey University Manawatu
Peter J. Lockhart, Massey University Manawatu
Polyploidisation events are known to precede ancient and recent plant radiation. Allopolyploid species in particular often exhibit enhanced dispersal and/or novel physiological characteristics. We have examined the relationship of the New Zealand endemic tetraploid Ranunculus nivicola with respect to its diploid parents: R. insignis and R. verticillatus. While these parent species have expanded the range of their Pliocene-Pleistocene species radiation into the New Zealand North Island, only R. nivicola is found on Mt Taranaki. The complete chloroplast genomes of all three species were sequenced and molecular markers were developed from these sequences to study the colonisation pattern of North Island species. Niche modelling was used to predict suitable habitat in the North Island and microhabitat differences were also recorded using data loggers at six different sites. These data were evaluated to find environmental parameters most relevant for explaining species’ distributions. After determining the importance of water deprivation, a drought stress experiment was conducted and gas exchange measured to examine physiological characteristics that differed between R. nivicola and R. insignis. HiSeq and Mi-Seq analyses of transcriptomes have now also been undertaken to identify and help characterize genes and alleles potentially important in facilitating North Island range expansion into drier and higher altitude habitat. Here we report on our findings.
Post-fire successional trajectories of temperate rainforests: Synthesizing empirical knowledge into models for predicting forest dynamics.
Alvaro G. Gutierrez, ETH Zurich
Jan Bannister, University of Freiburg
Andres Holz, University of Tasmania
Harald Bugmann, ETH Zurich
Che Elkin, ETH Zurich
Primary forests play an important role for the mitigation of climate change by storing carbon. However, changes in fire regimes may indirectly influence the capacity of forests to store carbon by altering forest regeneration and successional pathways. To what extent changes in fire regimes imperil the capacity of primary forests to storing carbon is relevant for the development of effective management and restoration strategies. Directly addressing these questions requires long term data on interactions between fire regimes and forest succession. However, forest dynamics models, particularly those based on interactions among individual trees and their environment, provide an alternative to explore these dynamic feedbacks. This is especially important in areas where long-term monitoring datasets will not be available in the coming decades. In this talk we focus on recent advances in forest dynamic modeling in southern Chile that reflect the current knowledge on tree physiology, tree species demography and disturbance history of temperate rainforests. Stand dynamic models applied in this region predict a variety of carbon storage trajectories along the succession. Changes in natural disturbance regime can result in a strong change in forest composition and carbon storage. Using a forest dynamics model operating at the landscape scale we analyze the underlying ecological mechanisms controlling post-fire successional trajectories, and test for the presence of thresholds and tipping points with regard to fire regimes that may fundamentally alter post-fire carbon storage trajectories. We will discuss research needs to improve the understanding of these dynamical processes operating at multiple spatial scales in forests.
Post-fire vegetation dynamics and feedbacks on fire susceptibility along a 150-year chronosequence in Nothofagus forests of New Zealand
Alan J. Tepley, University of Colorado at Boulder, USA
Thomas T. Veblen, University of Colorado at Boulder, USA
George L.W. Perry, University of Auckland, NZ
Māori colonization of New Zealand in the 13th century brought an ignition source into an infrequently burned landscape, facilitating the loss of nearly one-half of the forests that previously covered 85% of the landscape. Because native tree species are poorly adapted to survive fire or recolonize burned areas, many formerly forested areas persist as grasslands and shrublands. To characterize fire effects on Nothofagus forests and to better understand trajectories of post-fire vegetation development, fuel loading, and microclimate/fuel moisture,, we sampled a chronosequence of 15 paired burned/unburned stands ranging from 30 to 150 years since fire in the northern part of the South Island. Microclimate data were recorded over ten weeks in four pairs of stands. Burned stands were dominated by mānuka (Leptospermum scoparium) or kānuka (Kunzea ericoides) trees and had abundant, continuous fuel. Their microclimate was warmer and drier than adjacent, unburned forests, and the differences remained strong up to 150 years since fire. Only two burned sites had beech seedlings at a density > 400 seedlings/ha. Beech exhibited rapid post-fire regeneration, however, in two stands burned in the mid-18th century and up to 150 m from the margins of unburned forests. The persistence of dense fuel and a warm, dry microclimate > 100 years following fire generates a positive feedback that helps explain the rapid, extensive transformation from forest to shrublands following initial burning, but the finding of rapid forest recovery in some cases suggests repeated fires and/or livestock grazing may have been needed to complete this transformation.
Predicting distribution and habitat selection for an invasive species, the common brushtail possum (Trichosurus vulpecula), in an urban environment
Amy Adams, University of Otago
Prof. Katharine Dickinson, University of Otago
Dr. Bruce Robertson, University of Otago
Dr. Yolanda van Heezik, University of Otago
Effective management programmes for invasive species require an understanding of the species’ distribution, habitat and resource requirements at a local scale. The common brushtail possum (Trichosurus vulpecula) is one of New Zealand’s most destructive and damaging invasive pest species. Traditionally, control of possums has been focussed on rural and forest habitats, but evidence suggests that they may also be common in urban areas where they may be having negative impacts on native biodiversity. This study used site occupancy and resource selection methodologies to determine the distribution patterns and habitat selection of common brushtail possums within an urban environment. Data were collected via the use of WaxTags distributed throughout five distinguishable urban habitat types as well as from GPS collars fitted to twenty four possums programmed to collect positional fixes at 15 minute intervals. Possums had the highest occupancy in their natural habitat type (forest fragments) but were also present across a large proportion of residential habitat, with occupancy decreasing as housing density increased and green cover decreased. Modelling also showed that possums select urban habitats associated with high proportions of vegetation including residential areas. Data from this study show how brushtail possums can occupy and use a large area of the urban environment. Therefore, control measures aimed at possums within an urban environment will fail if they are restricted to the possum’s traditional habitat (forest fragments) without regard to surrounding residential areas which can support possums and thus provides a potential source for reinvasion.
Prerequisites and drivers for radiations in the Cape flora
Hans Peter Linder, University of Zurich
Renske Onstein, University of Zurich
Southern Africa includes almost half of all African Angiosperm species, and there have been radiations in several ecosystems, but especially the Cape flora and the semi-arid winter-rainfall region. Some of these radiations date to the Palaeogene, but most can be dated to the Neogene, or more particularly to the Miocene. Here we focus on the radiations in the Cape flora. We first ask what the attributes are of the clades that have radiated in this region. A detailed analysis of the sister-groups of several clades that radiated in the Cape revealed that small leaves, a low specific leaf area, and an evergreen habit are characteristic, and that the transition to these traits preceded the radiation in these clades. The syndrome could be associated with persistence in a pyrophytic environment, and could also reflect adaptations to cope with low soil nutrient availability and seasonal drought. However, these putative adaptations give no indication of the drivers of diversificaiton in the Cape radiations. Numerous drivers have been proposed, we review these. In a detailed analysis of the African Restionaceae we explore whether geographical isolation (allopatry) can be separated from ecological differentiation as a driver of speciation. This separated non-adaptive from adaptive models. For this we use a detailed phylogeny and species-level ecological information.
Progressive warming over the last 450,000 years offshore Tasmania of relevance to the alpine flora on the island
Patrick De Deckker, Australian National University
Timothy Barrows, Universith of Exeter
Sander van der Kaars, Monash University
Deep-sea gravity core Fr1/94-GC3 recovered on the East Tasman Plateau has a continuous record of sedimentation spanning the last 450,000 years, although its record displays a slow sedimentation rate. Multidisciplinary studies were applied to this core which include: stable isotopes of planktic and benthic foraminifers, coccoliths and benthic foraminifer assemblages, planktic foraminifer assemblages which were used to estimate sea-surface temperature [SST], alkenones SST reconstructions, percentage of aeolian quartz grains and pollen.
The findings indicate a progressive warming of the last 4 glacial periods which coincide with a diminution of the alpine pollen taxa during the same periods.
Equally, the warming trend is seen in most of the record at the sea surface.
Such a progressive warming has been recognized at 3 other locations, one in the western Pacific Ocean offshore the Great Barrier Reef, and 2 others in the Indian Ocean, thus suggesting a general trend in the Southern Hemisphere that bears significant implications for the conservation of alpine environments.
Project Kaka; Understanding the efficacy of 3 yearly pre-fed aerial 1080 applications for large scale forest restoration
James Griffiths, Department of Conservation
Wendy Ruscoe, Landcare Research
Mandy Barron, Landcare Research
Dave Carlton, Department of Conservation
Philippa Crisp, Greater Wellington Regional Council
In 2009 the Department of Conservation, in collaboration with Landcare Research and Greater Wellington Regional Council, implemented Project Kaka; a large scale forest restoration research programme in the Tararua Forest Park, Lower North Island, NZ. The research programme aims to determine the efficacy of three yearly pre-fed aerial 1080 applications for large scale forest restoration. Native plant and animal communities and target pests - possums, rats and stoats, are intensively sampled in one non-treatment area and two treatment areas. Sampling began in 2009 and will continue for at least 10 years, through multiple 1080 applications.
Early results indicate that treatment produces some positive ecological outcomes. Possum and rat relative abundance was reduced to low levels in both treatments for two bird breeding seasons following the application of 1080, and counts of some vulnerable bird species increased in treated areas. The research programme is only in its third year so these are preliminary inferences. However, these and other results indicate the sampling regime is sensitive to changes in the composition of plant and animal communities and will produce valuable information on the efficacy of 3 yearly pre-fed aerial 1080 applications for large scale forest restoration.
Projected Tasman Sea warming and extremes in the 21st century
Eric C. J. Oliver, Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
Neil J. Holbrook, Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
The western Tasman Sea is warming at almost four times the global average rate. Observational and modelling studies suggest that the increased sea surface temperature (SST), and reduced nutrient supply, is largely due to a spin-up of the South Pacific Gyre, and intensification of the East Australian Current (EAC) over recent decades. The extending EAC does not represent a simple change in the mean flow, but rather complex pulse and eddy changes, and is likely to affect higher order statistics such as the frequency of warming or cooling events. Extreme temperature events in particular can have catastrophic impacts on fragile coastal ecosystems. We investigate how the ocean climate in the Tasman Sea is projected to change during the 21st century. Here, we discuss results from a high-resolution (~10 km) ocean circulation model, forced by output from a large-scale climate model simulation, for the Tasman Sea region through the 2060s. Model biases are taken into account by evaluating the model representation of SST through the 1990s against satellite remote sensed AVHRR observations. Bias corrections are thus applied to the simulated 2060s period. We present the projected future ocean climate in terms of changes in the mean SST, SST variability, and occurrence of extreme temperature events. By mapping ocean climate changes and extremes, we identified specific regions where the change in climate is expected to be particularly strong. Finally, we discuss the ocean dynamic mechanisms that underpin these high-resolution simulations in light of climate change.
Quantification of wildling establishment from Australian Eucalyptus globulus plantations
Matthew Larcombe, School of Plant Sciences, University of Tasmania, Hobart, Australia
Joaquim S. Silva, 2Centre for Applied Ecology, Technical University of Lisbon, Portugal
René Vaillancourt, School of Plant Sciences, University of Tasmania, Hobart, Australia
Brad Potts, School of Plant Sciences, University of Tasmania, Hobart, Australia
In 2004 there were over 2.3 million hectares of E. globulus plantations growing worldwide, and this number has almost certainly increased. In Australia the E. globulus estate stands at 538,000 hectares. Although it is reported as invasive in five major geographic regions of the world, quantification of E. globulus spread is rare. We use a two-scaled survey technique to assess the level of, and factors associated with, wildling establishment from Australian E. globulus plantations. We surveyed 269 transects (290 km) along plantation edges across all main growing regions, and used density triggered paired plots (positive versus negative) to assess fine-scale factors influencing establishment. We recorded 4939 wildlings (17/km), 98 % of which occurred within 10m of the plantation edge (maximum dispersal distance 175m). There was significant variation in the rate of establishment between regions ranging from 1.2 to 39.6 wildlings/km. Generalized linear models showed that the probability of wildling presence also increased significantly with plantation age, and that wildling abundance was associated with burnt transects, and sites that received regular, relatively high rainfall and had lower mean annual temperatures. The only factor found to be influencing wildling presence at the fine-scale level (paired plot analysis) was the reproductive output of the plantation. The current level of E. globulus establishment in Australia is low in comparison to other well-known invasive forestry trees (e.g. Pinus sp.). However, given the relatively young age of the estate, localised establishment, and possible future changes in plantation management, monitoring is warranted.
Radiations and community assembly: adaptations and historical contingency
Willam Lee, Landcare Research; University of Auckland
Peter Heenan, Landcare Research
Andrew Tanentzap, Landcare Research
In New Zealand plant radiations are important because they frequently contribute much of the biodiversity. For example, amongst vascular plants, angiosperm genera with more than ten species make up over half of the flora. In general this diversification has been greatest in non-forested habitats across altitudinal zones. We examine evidence for adaptive and non-adaptive radiations in the indigenous flora using a combination of phylogenetic, correlative and experimental approaches. We also investigate the role of historical contingency and priority effects in structuring the composition and dominance hierarchy exhibited by plant radiations in select bioclimatic zones. The aim is to show how diversification mechanisms in island radiations can contribute to understanding the key processes determining large-scale patterns of biodiversity elsewhere.
Range shifts and adaptation to local conditions in parapatric insects
Mary Morgan-Richards, Massey University
Mariana Bulgarella, Massey University
Niki Minards, Massey University
Steve A. Trewick, Massey University
The consequence of past climate change can be used to infer possible biological responses to current rapid global warming. Evidence of changes in species’ distributions are common in phylogeographic studies world wide and can be understood in terms of both environmental limitations and species interactions. We infer past population history of a pair of parapatric tree weta species (Hemideina spp) where competitive exclusion interactions are thought to control their distributions, and the climate is likely to be responsible for determining the winner of these interactions. We also look for evidence of local adaptation by comparing growth rates under controlled conditions of individuals that have originated from high and low altitude locations. Although measures of genetic diversity support past changes in species’ distributions predicted from their current parapatric range, we have also detected convergent evolution of local adaptation in growth rates. Although ‘evolve’ versus ‘move’ are frequently regarded as mutually exclusive alternative responses to climate change, we should perhaps accommodate both into our models. In these two insect species, both range shifts and local adaptation seem likely to result from current climate warming.
Re-assessing growing season definitions in oceanic and continental treeline climates
Ellen Cieraad, Landcare Research
Matt McGlone, Landcare Research
A global study has showed treelines converge on a growing season root zone mean temperature of 6.7°C. However, some oceanic Southern Hemisphere treelines, including those from New Zealand, appeared to be exceptions, with ‘anomalously warm’ mean growing season temperatures of over 9°C documented. We have now established the seasonal temperature regime at 20 New Zealand treeline sites across a 13° latitudinal and 1520 m altitudinal range. Soil temperatures measured at a subset of these treelines show they are not anomalously warm compared to treelines globally. However, a growing season definition based on a mean soil temperature threshold gave inconsistent results in oceanic climates with long, variable growing seasons.
Our study shows that daily minimum, rather than daily mean, soil or air temperatures provide a better characterisation of treeline. If the growing season was defined by the crossing of a 2°C daily minimum threshold, mean minimum growing season air temperatures provided a highly consistent tree isotherm across the wide climatic range of treelines in New Zealand. Growing degree days were highly variable between treelines, but the number of days with minimum temperatures above 5°C converged on 90 days per annum. We suggest these thresholds relate to fundamental limits to tree growth, such as photosynthesis and wood formation, which manifest at a daily minimum temperature between 2 and 5°C. We show that this approach applies well to temperate treelines in other regions worldwide.
Rebuilding pollination networks: are trajectories for recovery predictable and does it matter?
Caroline L. Gross, University of New England
Laura B. Vary , University of New England
Can we restore pollination networks? The community dynamics of plants and their pollinators in intact ecosystems is key knowledge for the restoration of degraded communities that are missing plant and pollinator components. Using a comparative approach involving six sites, of either intact or two levels of degraded woodlands for an endangered ecological community (EEC) in eastern Australia, we are identifying irreplaceable pollination services for this EEC and their hub species that provide or facilitate the majority of pollination services. Using fruit to flower ratios and pollinator network analyses we show that hub plant species common to all habitat types generally maintain their fecundity in degraded habitats. In some cases this is associated with a switch in floral visitor type although feral honeybees were a consistent component in each habitat type. Hub species such as the shrub Hibbertia linearis (Dilleniaceae) were found to provide non floral resources for hub insect species. The Satin-Green Forester (Pollanisus viridipulverulenta), a diurnal moth of the Zygaenidae, is a major floral visitor to plants in the degraded habitats and is supported by the presence of its larval food-plant, Hibbertia linearis, although it does not utilise the flowers of this species. This indicates that to cater for important non-hymenopteran insects we may need to expand the use of floral networks.
Reconstructing the recovery of Subantarctic Campbell Island
Alexander Fergus, 50 Degrees South Trust
Colin Meurk, Landcare Research
Two centuries ago Europeans made landfall on Campbell Island, initialising rapid ecological change in a Subantarctic marine-regulated landscape. Sealing, fire, pastoralism, whaling, and the inadvertent introduction of rats severely impacted the island’s biota; devastating marine mammal, terrestrial bird and invertebrate populations; and cropping unique macro-forb vegetation types to low turfs. Toward the end of the twentieth century all mammalian introductions had been eradicated from the island, leaving a suite of exotic plants, and the historical imprint of ecological change. Landscape change has been documented in an ongoing photographic record dating from 1888. Permanent quantitative vegetation monitoring began in 1970 and has continued regularly; sporadic monitoring of seabirds and sea mammals has been conducted; and monitoring of invertebrate populations was recently initiated. From these sources I report on the state of the island, the extent of the recovery, and the limitations of reconstructing the recovery process in the Subantarctic from an incomplete record or without baseline data. The accuracy of extrapolating trends across different monitoring techniques and the role of monitoring driving management in this system are discussed.
Recovery of alpine vegetation on the Eastern Central Plateau, Tasmania: results from 20 years of monitoring and future potential under climate change.
Kerry Bridle, Tasmanian Institute of Agriculture
Jamie Kirkpatrick, University of Tasmania
The Eastern Central Plateau, Tasmania has been severely impacted in the past by stock grazing and landscape scale fires. While the Central Plateau is the largest extent of alpine vegetation in Australia, it also is known for having the largest areas of sheet erosion due to fire (wild and anthropogenic) and grazing from livestock and wild herbivores (including rabbits). Livestock have been excluded from public land on the Central Plateau since 1989. Rabbits and native herbivores, namely wallabies and wombats, provide much of the grazing pressure. A series of grazing exclosures were erected at four degraded sites in 1991. Two exclosures at each site excluded all vertebrate herbivores and two excluded wallabies but allowed access to rabbits. Two controls allowing access to all herbivores, were also surveyed. These exclosures have been monitored every five years since 1991.
Scientists from the Climate Futures for Tasmania project have provided downscaled projected climate data for 10 x 10 km grid cells. The Eastern Central Plateau is projected to be the most severely impacted region in the state, experiencing greater increases in temperature and greater decreases in rainfall under climate change projections. This presentation will discuss the natural recovery of vegetation in the exclosures with reference to past events and forward climate projections.
Recreation Ecology Research in the dry Andes: Aconcagua Provincial Park
Agustina Barros , School of Environment, Griffith University, Australia
Catherine Pickering, School of Environment, Griffith University, Australia
The Andes is the highest and longest mountain range in the Southern Hemisphere. It has high biodiversity and is a primary water source for South America. The dry Central Andes (31°-35°S) has few inhabitants due to elevation, harsh weather and limited road access, although peaks over 6000m attract mountaineers who use pack animals for transport. Recreation is a main source of disturbance, including the highest peak, Mt Aconcagua (6962 m), receiving over 30,000 day visitors and 7,000 mountaineers and pack animals each summer. Vegetation and associated biodiversity in Aconcagua is often restricted to valley floors, where tourism use is concentrated. To start addressing the deficit in recreation ecology research in the region we assessed the impacts of: 1) trampling, 2) grazing by pack animals and 3) fragmentation from trails on vegetation in Aconcagua. The relative impact of trampling by hikers and pack animals was assessed using an experimental protocol. Pack animals did more damage than hikers per pass, although the alpine meadow was comparatively resistant to both disturbance types due to the dominance of the sedge Carex gayana. When grazing by pack animals was excluded for a growing season, high altitude meadows rapidly recovered biomass. The intensively used main valley contained 12 km of informal trails that fragmented vegetation into smaller patches with low vegetation cover and high weeds occurrence. Concentrating use and restricting pack animals grazing will reduce tourism impacts in this Park. These results are useful for managers of Aconcagua and other parks in the dry Andes.
Redefining Bucculatricidae: a sister group with a southern distribution largely associated with Eucalyptus vis-à-vis Bucculatrix (Lepidoptera)
Marianne Horak, CSIRO Ecosystem Sciences, Canberra, Australia
M. F. Day, CSIRO Ecosystem Sciences, Canberra, Australia
C. Barlow, CSIRO Plant Industry, Canberra, Australia
E. D. Edwards, CSIRO Ecosystem Sciences, Canberra, Australia
Y. N. Su, CSIRO Ecosystem Sciences, Canberra, Australia
S. L. Cameron, Queensland University of Technology, Brisbane
Elucidation of the life history of the iconic but enigmatic scribbly moths of the genus Ogmograptis Meyrick, mining in the bark of certain smooth-barked Eucalyptus species, resulted in the recognition of two speciose Australian genera of the Bucculatricidae. They greatly expand this small family, until now consisting of only the very large world-wide Bucculatrix Zeller and the monotypic South African Leucoedemia Scoble & Scholtz. Study of immatures revealed three synapomorphies for the family: a longitudinally ribbed cocoon and a larva with modified tarsal setae and an internal skeleton in the last abdominal segment. Adult morphology provides unique synapomorphies linking the Australian Ogmograptis and Tritymba Meyrick with the South African Leucoedemia. The clade comprising these three southern genera, rich in plesiomorphic characters, is the sister group to the highly derived Bucculatrix, a phylogeny supported by DNA data. The unique and complex life history of both Ogmograptis and Tritymba, with larvae mining in the cork and vascular cambial layers respectively of Eucalyptus and concluding with obligate feeding of the last instar on callus tissue produced within the mine, suggests a unique plant-insect interaction. Such a close link between host and herbivore points to a long common history of the two genera on Eucalyptus. A Gondwanan origin has been indicated for Eucalyptus and for the Anacardiaceae, the host family of Leucoedemia, further emphasizing the southern source of this bucculatricid clade.
Regional-scale analysis of spatial fire occurrence in western Patagonia: Vegetation type, humans and feedbacks
Juan Paritsis, INIBIOMA-Comahue-CONICET
Andrés Holz, School of Plant Science-UTAS
Thomas Veblen, University of Colorado
Thomas Kitzberger, INIBIOMA-Comahue-CONICET
Although there is a growing recognition of the important role played by humans as drivers of wildfire activity globally, regional variations in the effects of humans on wildfire remain poorly understood. We evaluated the effects of biophysical and anthropogenic variables on fire activity at regional scales in western Patagonia, where most ignitions are due to humans. We used Landsat images to map fire perimeters in four extensive regions in western Patagonia from 43 to 53°S, and we modeled fire activity across space for each of these regions which differ in land use as well as biophysically. In the field, we characterized post-fire fuel structure and we recorded microclimatic parameters relevant to fire (i.e. temperature and relative humidity) in two key widespread vegetation types –shrublands and Nothofagus pumilio forests. Our results show a significant and consistent association of differential probability of fire occurrence for particular vegetation types. We also found that human variables (i.e. proximity to roads and towns) had contrasting effects on fire activity depending on the region evaluated. While fire-prone shrublands regenerate to a similar fuel condition after burning, the relatively fire resistant N. pumilio forests tend to transform into more flammable shrublands after fire. This study highlights the complexity of fire responses to anthropogenic variables depending on predominant land-use and configuration of infrastructure, such as road and/or town density. Furthermore, our results suggest the presence of positive feedbacks among vegetation type, land use and fire, which may be driving these ecosystems into alternative states.
Replenishing bee forage deficits due to removal of environmental weeds in New Zealand
Linda Newstrom-Lloyd, Landcare Research
Finn Scheele, Landcare Research
Marco Gonzalez, AsureQuality
Ian Raine, GNS Science
Karyne Rogers, GNS Science
Xun Li, GNS Science
Gaye Rattray, Landcare Research
Tony Roper, AsureQuality
Native and exotic bees both serve as important pollinators in natural and agricultural ecosystems in New Zealand. In agriculture, the most important pollinator for crops and pastures is by far honey bees (Apis mellifera) because colonies can be moved and managed in great numbers. Threats to honey bee colonies are worsening in the same manner as overseas for three reasons: diseases and pests (e.g. varroa); misuse of toxic pesticides; and removal of bee forage plants. The increasing loss of bee forage is a longstanding conflict of interest between beekeepers and conservationists. Many traditional bee forage plants such as gorse, broom, and willow are being eliminated or controlled because they are environmental weeds. However, the conservation of any pollinator relies on preservation of sufficient food supply, a factor often overlooked in restoration, conservation and farming programmes. The lost forage plants have not been replaced to the increasing detriment of bee pollinator services for agriculture. The Trees for Bees NZ project is working to replenish the bee’s nutritional losses at two critical times: spring population build-up and autumn preparation for overwintering. An evaluation of protein in pollen, the primary nutrient for bee reproduction and growth, has shown that several native plants have high-protein pollen although eco-sourcing is an issue. Many exotic species also have high-protein pollen but need to be evaluated for weed potential. A database of candidate replacement plant species and four demonstration farms are being developed.
Resinicolous Mycocaliciales - new findings from Southern Hemisphere forests and European amber
Jouko Rikkinen, University of Helsinki
Resins and other plant exudates effectively repel parasitic fungi. However some fungi grow exclusively on resin substrates. Many of these are hyphomycetous ascomycetes, but also several species in the Mycocaliciales (Ascomycota) produce stalked ascocarps on hardened resin or resin impregnated wood. Most of these fungi live on a single plant species or genus, mainly on conifers in boreal and temperate forests of the Northern Hemisphere. However recent findings have indicated that may additional taxa live on exudates of subtropical and tropical angiosperms, and that Southern Hemisphere forests may also be rich in species. Interestingly, the recently described Chaenothecopsis quintralis has only been collected on dung of the marsupial Dromiciops gliroides which is the primary seed disperser of Tristerix corymbosus in the temperate forest of southern South America. The fungus probably exploits viscin mucilage covering the seeds and effectively disperses together with its host plant. Additional species from the Southern Hemisphere include Chaenothecopsis schefflerae from Schefflera digitata in New Zealand and an undescribed Chaenothecopisis species from Agathis ovata in New Caledonia. Well preserved fossils in European Eocene and Oligocene ambers show that the ecology and morphology of some resinicolous mycocalicioids has remained remarkably constant for tens of millions of years. One fossil fungus had produced branched and proliferating fruiting bodies similar to those of several extant species. This shared morphology may represent a morphological adaptation to life near active resin flows: the proliferating ascomata can effectively rejuvenate if they are in the danger of being completely overrun by fresh exudate.
Resistance/resilience to changing climate and fire regime varies between plant functional trait groups
Neal Enright, Murdoch University
Joe Fontaine, Murdoch University
Byron Lamont, Curtin University
Ben Miller, Western Australia Botanic Garden and Parks Authority
Vanessa Westcott, Melbourne University
Disturbance frequency, such as the interval of time between successive fires, is widely recognised as an important driver of vegetation structure and composition. Of particular interest is the effect of shortened fire intervals and their interactive effects with changing climate on plant communities. Concern regarding short-interval fires (aka reburns) is widespread but studies are often limited to a single example. Using a series of experimental fires (N=33) over four years, we studied the effects of shortened fire intervals ranging in time from 3-24 years in high diversity Mediterranean shrublands of Western Australia. Plots were measured immediately before and 2-3 yrs after fire where all species were identified and counted. Species were classified into two plant functional types based on fire-related traits of post-fire regeneration (sprouting vs. non-sprouting) and seed storage (canopy, soil) and analysed with respect to their pre to post fire change. Fire interval was a strong predictor of post-fire changes in abundance with non-sprouting, canopy-stored seed species being the most sensitive to short-interval fires and resprouting, soil-smoke stored species being the least sensitive. Winter rainfall also influenced post-fire persistence with a strong interaction with fire interval. Neutral responses of most plant functional types (i.e. persistence through fire of species) were achieved by approximately 9-11 years following fire, depending on plant functional type and winter rainfall. Application of prescribed fire at shorter intervals is likely to result in reduction of certain plant functional types on the landscape.
Response of alpine vegetation to altered snow regimes in Otago, New Zealand.
Janice Lord, Botany Department, University of Otago, Dunedin
Katharine Dickinson, Botany Department, University of Otago
Stephan Halloy, The Nature Conservancy, Southern Andes Conservation Programme
Allison Knight, Botany Department, University of Otago
Tanja Maegli, Botany Department, University of Otago
Alan Mark, Botany Department, University of Otago
Climate change models currently predict increased westerly winds and consequently reduced precipitation and snow cover in alpine areas east of the Alps in southern New Zealand. A reduction in snow cover would expose plants that are currently protected by snow in winter and spring to greater extremes of temperature and increased risk of frost damage. We used a reciprocal transplant experiment of intact turfs of alpine vegetation to investigate how shifts along a snow cover gradient affected growth, survival and community composition. Replicated 60cm x 60cm x 15cm turfs were transplanted in 2003 between four habitat types on the Rock & Pillar Range, Otago, New Zealand: late-melting snow bed and early-melting snow bed in gullies, herbfield on upper slopes and exposed cushionfield on the summit plateau. Measurements of leaf production over three years in indicator Celmisia species showed that snowbank Celmisia haastii suffered reduced growth when transplanted to the cushionfield. However, survival was more affected by species-specific herbivory than increased exposure directly. Shifts in vegetation composition in turfs have been slow, with changes due more to gradual loss of original species and marginal invasion by the surrounding vegetation. Colonisation of transplanted turfs by dispersed propagules has been rare, with the alpine lichen Thamnolia vermicularis being the only species to rapidly invade turfs following transplantation.
Room to expand - past shifts in southern hemisphere climate space and possible consequences for current biodiversity patterns
Ralf Ohlemüller, Department of Geography, University of Otago
H. Peter Linder, Institute of Systematic Botany, University of Zurich
Climate sets the baseline conditions for life on Earth. The current distribution of species and ecosystems at large spatial scales is shaped by the spatial and temporal shifts in the distribution of climatic conditions. These multidimensional climatic conditions (the climate space) of a region can shrink or expand in response to global climate change. The speed and the velocity at which climate space has shifted in the past can help to explain current biodiversity patterns; models of future shifts allow us to quantify and map which climate niches are likely to be at risk from projected future climate change. In addition, past spatiotemporal dynamics of climate space of a taxon will have affected the degree and speed with which speciation and diversification has occurred.
Here, we introduce the concept of shifting climate space and investigate the role of past shifts in climate space in explaining species richness patterns in southern hemisphere danthonioid grasses. We quantify past shifts (Last Glacial Maximum [LGM], ca. 21k ya) in danthonioid climate space for South America, Southern Africa, Australia and New Zealand. Depending on the model of past climate reconstruction used, Southern Africa and New Zealand experienced the largest expansion or smallest reduction in danthonioid climate space during transitions from colder (LGM) to warmer (current) periods. In contrast, danthonioid climate space in South America shrinks substantially during these transitions, whereas in Southern Africa, it is consistently available. We illustrate the relevance of these results for current patterns of danthonioid biodiversity in the southern hemisphere.
Season of prescribed fire is important for reproductive success in a species with fire stimulated reproduction.
Philip Ladd, Murdoch University
Andrew Nield, Murdoch University
Neal Enright, Murdoch University
Podocarpus drouynianus a dioecious reprouting shrub of the jarrah forests of south western Australia, exhibits obligate fire-stimulated flowering. P. drouynianus regenerates rapidly from its lignotuber following fire and produces sporophylls in the one - two years following fire but almost none thereafter. Prescribed burning is commonly utilised throughout south western Australia to manage fuel loads for the protection of lives and property. The majority of prescribed burning activities are undertaken during the spring. Land management agencies attempt to mimic 'natural' fire regimes to assist biodiversity conservation. However fire season is not often explicitly considered in the pyrodiversity paradigm in which prescribed burning decisions are made. This may lead to potentially negative demographic consequences for those species whose life histories are not atuned to current fire season. This study examined the relationship between fire season (autumn/spring), reproductive output and demography for P. drouynianus,, a species of key commercial and biodiversity value. Post-fire seed production and seed weight was significantly higher in autumn-burnt females 12 months following fire in comparison to individuals burnt the preceding spring. Potential seed viability was also significantly higher for autumn-burnt plants. Population-level effects may also have negative impacts on P. drouynianus demography, with females within a small population burnt in autumn producing very few seeds 12 months following fire. The reproductive output of P. drouynianus is significantly affected by fire season and should be considered as part of improving prescribed burning for biodiversity conservation.
Seedfall monitoring: measuring plant-frugivore interactions with seed traps
Jenny J. Ladley , University of Canterbury
Dave Kelly , University of Canterbury
Elaine F. Wright , Department of Conservation
Peter J. Bellingham , Landcare Research
Seedfall varies greatly among years (mast seeding), which can have widespread community effects from pulsed inputs of resources. In New Zealand, seedfall monitoring began in the 1950s but has been patchy in both geographic and taxonomic spread. A recent intiative has since 2004 created a systematic network of seedfall monitoring sites covering seven sites and 24 tree species, many of them not previously studied for seedfall variability. Here we present some early results.
The longest-established site, Pelorus Bridge, now has 12 years of data on six fleshy-fruited species, all important food for native frugivorous birds. These data confirm early reports that, in the Podocarpaceae small-seeded species had high inter-annual variability (Dacrydium cupressinum, Dacrycarpus dacrydioides) but the larger-seeded Prumnopitys ferruginea had low variability, while Beilschmiedia tawa (Lauraceae) was intermediate. Despite previous work showing significant wide-scale synchrony among masting species in New Zealand, seed crops for different species in Pelorus Bridge were largely uncorrelated across years, increasing the reliability of fruit resources as a whole.
Seeds fall into traps either with flesh intact if they have not been dispersed, or clean if they have passed through a frugivore. The percentage of clean seeds gives a measure of dispersal service to plants by birds throughout New Zealand. Data from 163 species-site-year combinations showed very high % clean seeds for Hedycarya arborea (Monimiaceae), D. dacrydioides, and Podocarpus totara, but low % clean for Elaeocarpus dentatus (Elaeocarpaceae). There was no strong relationship between fruit size and percent clean.
Seeds on acid: does litter chemistry of Agathis australis (New Zealand Kauri) influence vegetation composition?
Sarah Wyse, School of Biological Sciences The University of Auckland
Bruce Burns, UNKNOWN
Agathis australis exerts a substantial influence on soil properties and nutrient cycling, and mature specimens form an acidic organic soil layer up to 2m deep. A distinctive suite of plant taxa also usually accompanies such specimens. The phytotoxicity of plant parts and exudates effects species distributions surrounding many plants, and the presence of such phytotoxic compounds is particularly prevalent amongst conifer species. To investigate the phytotoxic potential of kauri leaf litter, I extracted water-soluble compounds from fresh litter, and conducted bioassays of seed germination and seedling growth in these extracts. To determine whether an observed phytotoxic effect of kauri litter extracts could potentially produce the vegetation patterns associated with kauri, I then conducted these same bioassays in organic soil taken from beneath mature kauri, along with pH neutralised kauri organic soil. The results revealed the presence of phytotoxic chemicals within kauri litter that, with the exception of kauri seed, inhibited the germination of all species tested. The germination and growth of species not found alongside kauri were significantly inhibited in the organic soil, yet not in the neutralised organic soil. In contrast, there was no effect of the organic soil on the germination and growth of kauri-associated species. These results suggest that phytotoxic chemicals within kauri litter are not present in sufficient concentrations in the organic soil to have a biological effect, however the acidity of this soil may play a role in structuring the composition of plant communities associated with kauri.
Sex in the south: Pollination biology of subantarctic megaherbs
Janice Lord, Botany Department, University of Otago
Lorna Little, Botany Department, University of Otago
Vickey Tomlinson, Botany Department, University of Otago
Lynne Huggins, Southland Conservancy, Department of Conservation
The striking size and colour of subantarctic flowers are a puzzle, as potential pollinating insects are scarce and related mainland New Zealand plants often have white flowers. Given the spectacular nature of the subantarctic flora it is surprising how little is known about pollination and reproduction. We examined the pollination biology of eight endemic plant species on subantarctic Campbell Island, by bagging and hand-pollinating flowers and observing flower visitors during December 2010. Of the six hermaphroditic species, Pleurophyllum criniferum and Damnamenia vernicosa were capable of autonomous selfing, and Veronica benthamii was self-compatible. P. hookeri appeared to be self-incompatible. Stilbocarpa polaris, previously described as polygamodioecious, was found to be a strictly dichogamous hermaphrodite in which selfing would only rarely occur. Small flies were abundant flower visitors, particularly near sea level where they were particularly common on S. polaris and male Bulbinella rossii inflorescences. The wingless endemic fly C. filipennis and flightless endemic moths were observed visiting flowers of B. rossii, V. benthamii and P. hookeri at higher altitudes. No daytime flower visitors were observed on dioecious Anisotome latifolia but at night-time the inflorescences of Bulbinella, Anisotome and Veronica are were visited by large numbers of adult and juvenile wetas. Individual wetas captured on female Anisotome and Bulbinella inflorescences carried pollen on their bodies, so are potentially capable of pollinating these dioecious species. Our study shows that subantarctic plants may be more reliant on insect visitors than previously thought and the subantarctic weta may be a key pollinator of some species.
Signatures of hybridization in defense-related genes as a feature of the Pachycladon radiation in New Zealand’s Southern Alps
Claudia Voelckel, Massey University Manawatu
Matthias Becker, Massey University Manawatu
Nicole Gruenheit, The University of Manchester
Oliver Deusch, Waltham Centre for Pet Nutrition
Mike Steel, University of Canterbury
Peter Heenan, Landcare Research Lincoln
Patricia McLenachan, Massey University Manawatu
Olga Kardailsky, University of Otago
Peter Lockhart, Massey University Manawatu
Selection by herbivores and pathogens has been suggested to have been a driver of diversification in the recent radiation of Pachycladon, a genus of ten species native to New Zealand’s Southern Alps. This had been inferred from transcriptomics studies which unravelled remarkable differences in defence gene expression across Pachycladon accessions. To investigate the evolution of these defence genes, we sequenced three genes that have key roles in glucosinolate hydrolysis and that have been implicated in adaptive phenotypes in the model plant Arabidopsis thaliana. We focused on P. enysii and P. fastigiatum which were previously predicted to have survived the last glacial cycles in different types of refugia. Allelic diversity in the three defence loci ESP, ESM1 and MVP1 was compared with haplotype diversity in chloroplast-wide SNP markers. The latter were developed from Pachycladon chloroplast genomes assembled from next-generation sequencing reads. Chloroplast SNP analysis revealed extensive hybridization between P. enysii and P. fastigiatum in their Southern range. Moreover, when applying a test that distinguishes lineage sorting from hybridization, signatures of hybridization were confirmed for all three defense loci. In ESM1 and MVP1, we also found alleles which have arisen by recombination of P. fastigiatum and P. enysii alleles. This recombination most likely led to the restoration of functional alleles in P. enysii. We interpret our findings in the light of theories that attribute a great role for hybridization in the acquisition of adaptive traits and make suggestions for conservations of species that are part of an adaptive radiation.
Simulated climate-sensitive interactions between vegetation dynamics and wildfire in an agent-based model of land-use change
Gabriel I. Yospin, Montana State University
Scott D. Bridgham, University of Oregon
John P. Bolte, Oregon State University
Alan Ager, USDA Forest Service
Timothy Sheehan, Conservation Biology Institute
Bart R. Johnson, University of Oregon
We developed a new climate-sensitive vegetation state-and-transition model (CV-STM) to simulate the changes in vegetation associated with changing climate, human land-use and wildfire. Rates of vegetation change in a stand biometric model, FVS, parameterize the transition probabilities in CV-STM. CV-STM then uses biogeographic and biogeochemical projections from a dynamic global vegetation model (DGVM) to adjust and constrain its transition probabilities. CV-STM can run in a GIS environment, in conjunction with a mechanistic model of fire spread and effects, and an agent-based model of land-use change. As a component in this coupled, spatially-explicit modeling, CV-STM provides information on the species composition and structural stage of stands of trees, at a spatial resolution as fine as 0.5 ha. Simulations in a 1,000 km2 study area showed changes in successional trajectories under alternative climate and wildfire scenarios. Climate and wildfire scenarios showed strong interactions. Changes in CV-STM were generally slower than in the DGVM, due to key model constraints. For example, subtropical tree species were less abundant at the end of simulations in CV-STM than in the DGVM, because stand-replacing disturbances were necessary to kill long-lived trees and allow new or sub-dominant species to become dominant. Our results indicate that DGVMs may be overestimating the rates of vegetation change, especially in the absence of stand-replacing disturbances. Modeling tools such as CV-STM that simulate interactions and feedbacks between climate, vegetation and land-use change are critical for developing effective plans that will help society adapt to rapidly changing climate.
Simulating disturbance, climate, vegetation, and human interactions and feedbacks on western US landscapes using landscape modeling
Bob Keane, USDA Forest Service Rocky Mountain Research Station
Rachel Loehman, USDA Forest Service Rocky Mountain Research Station
Lisa Holsinger, USDA Forest Service Rocky Mountain Research Station
Jason Clark, USDA Forest Service Rocky Mountain Research Station
Changes in climate and human activities have caused important shifts in disturbance and vegetation dynamics, and most of these shifts have resulted as a consequence of unanticipated feedbacks and interactions. Understanding and forecasting possible changes in landscapes of the western US will require that important feedbacks, interactions, and connections between ecosystem processes be addressed. We used the mechanistic ecosystem dynamics model FireBGCv2 to simulate effects of present and future climates and land management on disturbance and vegetation dynamics on several landscapes in the western United States. We present simulated landscape responses to changes in climate and land management as a result of the complex interactions of disturbance and vegetation with climate and humans. The predicted response of wildlife habitat, fire occurrence and severity, landscape vegetation composition, carbon pools, human development are simulated from complex interactions with fire regime, mountain pine beetle outbreaks, blister rust infections, grazing regimes, and land management policies of fire exclusion for western US landscapes in Glacier National Park, west central Montana, Yellowstone National Park, and central Oregon. Simulation results indicate that interactions among climate changes and disturbance processes impact vegetation species conversions and amplify fire dynamics.
Solving problems in the identification of living and fossil leaves: how cuticles can help
Jennifer M Bannister, Department of Botany, University of Otago, PO Box 56, Dunedin NZ
John G Conran, ACEBB, School of Earth and Environmental Sciences, The University of Adelaide, SA 5005 Australia
Daphne E Lee, Department of Geology, University of Otago, PO Box 56, Dunedin NZ
Various methods can be used to isolate cuticles from the rest of the leaf. Extant leaf cuticles can usually be prepared using warm hydrogen peroxide, but isolating cuticles from fossil leaves depends on the type of fossilisation and different methods may be needed. Cuticles need staining and mounting on slides for microscopic examination and photography, or mounting directly onto stubs for SEM observation. Cuticular features useful for identification include stomatal arrangement and size, hairs (trichomes; often not preserved on fossil leaves), trichome bases, glands, size and thickness of epidermal cell walls (seen as a pattern on the cuticle) and epidermal surface ornamentation. Examples where cuticles proved useful include: determining the identification of an herbarium specimen of Litsea reticulata to be incorrect; identifying sterile Cordyline specimens from cuticular ornamentation; and distinguishing species of Winteraceae from leaves only.
Many fossil cuticles from forest trees and lianes growing round Foulden Maar and in a swamp forest at Newvale have been identified using cuticular characters and, where possible, leaf features, particularly venation. At Foulden Maar large numbers of leaves (c. 45% of the total) can be identified as Lauraceae because of their distinctive stomatal arrangement. Using cuticular features, about 120 of the best preserved leaves were sorted by cluster analysis, adding leaf features where available, with 10 species of Lauraceae recognised. However, reliance on leaf features alone can be misleading when identifying fossil leaves, for example several different groups have similar leaf features to Mallotus/Macaranga leaves.
Southern hemisphere forests shedding light on reasons for amber accumulations.
Leyla J. Seyfullah, Georg-August-Universität Göttingen
Christina Beimforde, Georg-August-Universität Göttingen
Vincent Perrichot, Université Rennes 1
Jouko Rikkinen, University of Helsinki
Alexander R. Schmidt, Georg-August-Universität Göttingen
Amber can be described as occurring in ‘bursts’ during earth history, particularly in the Late Triassic, the Early and mid Cretaceous and the Eocene to Miocene, with many large deposits found worldwide. The causes of these unusual deposits are unclear and there are several theories surrounding these extensive outpourings of fossil resin. There are two key biological questions surrounding amber: which plants produced the resin; and why did they produce such quantities? Numerous chemical studies show that amber, particularly the older fossil resins, was predominantly produced by coniferous trees, with much smaller quantities being produced by angiosperms, although the parent plants of some ambers are still unknown. In this study we start to address the question of why some conifers in their natural environment produce large quantities of resin today and whether this aids understanding of amber production. We focus on two genera of the highly resinous Araucariaceae family: Agathis Salisbury and Araucaria Jussieu, since their resins appear to have chemical similarities to fossil resins found from numerous different localities and geological ages. We tested several different hypotheses of resin production reasons in the natural environment. In New Zealand both extant and in situ subfossil Agathis australis (D. Don) Loudon was investigated, to test whether disease and disaster hypotheses of large resin secretion could be supported. In New Caledonia, hypotheses tested included resin production in response to insect damage (Araucaria humboldtensis Buchh), mechanical damage (Agathis ovata Moore ex Vieill. Warb., Araucaria columnaris (J.R. Forst.) Hooker) and fire (Araucaria columnaris).
Southern Hemisphere Large Scale Circulation: sensitivity to glacial versus extreme warm conditions.
Maisa Rojas, Department of Geophysics, Univ. of Chile
The effect of glacial climate versus high CO2 world boundary condition on the strength and latitudinal position of the Southern Hemisphere Westerly winds (SHW) is investigated. To this aim the existing Last Glacial Maximum (LGM) simulation from the PMIP2 and PMIP3 experiments, as well as the abrupt4xCO2 simulation from CMIP5 are used. There is a clear and strong response of the SHW to 4xCO2, that includes intensified and poleward shifted winds in all simulations. This is coherent with recent observations and projections to 21th century increase in atmospheric CO2 concentration from various climate change scenarios. However, for the glacial climate, the response is much more limited and less unambiguous. 6 of the 8 LGM simulations show a decrease in the winds with a non-significant small equatorward shift in the position of the maximum near surface winds. The large-scale circulation, diagnosed by the mean meridional circulation shows a coherent contraction of the tropical circulation, but at mid to high latitudes it is the simulation of sea-ice extent that determines the change of SHW to glacial boundary conditions. This suggests that constraining LGM sea-ice extent around Antarctica might help to elucidate this long-standing debate on how the SHW changed during the LGM.
Southern scales of gene flow and colonization by kelp-rafting
Raisa Nikula, University of Otago, Allan Wilson Centre for Molecular Ecology and Evolution
Hamish G. Spencer, University of Otago, Allan Wilson Centre for Molecular Ecology and Evolution
Jonathan M. Waters, University of Otago, Allan Wilson Centre for Molecular Ecology and Evolution
We have conducted an array of molecular marker studies to assess the levels of genetic connectivity among populations of bull-kelp epifauna in the Southern Hemisphere over different geographic scales. On a circumpolar scale, peracarid crustaceans tightly associated with Durvillaea antarctica, and lacking autonomous means of dispersal, show patterns of mitochondrial DNA diversity that indicate fairly recent long-distance colonisation by kelp-rafting across thousands of kilometres of open ocean. Among New Zealand subantarctic islands, which have been isolated by ocean gaps for millions of years, several species of kelp-associated molluscs and an amphipod display genetic patterns that indicate regular, on-going gene flow across ocean gaps of hundreds of kilometres. On a more local scale, our comparisons of population-genetic connectivity in mollusc species pairs that have preference for either intertidal rock surfaces or bull-kelp holdfast cavities suggest that kelp-rafting by adults enhances coastal gene flow even in species with a pelagic larval phase. Rafting is clearly a potent dispersal mechanism driving gene flow in kelp-associated invertebrate species in the Southern Hemisphere, where robust and strongly buoyant seaweeds dominate the rocky intertidal and powerful current systems are in operation, efficiently transporting rafts over long distances. But does rafting-mediated dispersal make a similar mark on the distribution and levels of marine biodiversity in both the Southern and Northern Hemispheres? To answer this question, we review genetic studies of marine invertebrates associated with buoyant substrates from the Northern Hemisphere, and compare their geographic and temporal scales of gene flow with those in the Southern Hemisphere.
Species tree phylogeny and character evolution in the genus Centipeda (Asteraceae)
Stephan Nylinder, Swedish Museum of Natural History, Stockholm, Sweden
Bodil Cronholm, Swedish Museum of Natural History, Stockholm, Sweden
Peter J. de Lange, Department of Conservation, Auckland, New Zealand
Neville Walsh, National Herbarium of Victoria, Victoria, Australia
Arne A. Anderberg, Swedish Museum of Natural History, Stockholm, Sweden
Interpretation of phylogenetic relationships based on morphology can prove difficult when key features are reduced and sometimes difficult to distinguish. The small genus Centipeda (Asteraceae, Athroismeae) seems to have undergone extensive reductions in flower characters and growth habit during the process of radiation and adaption to its present habitual preferences. A recent taxonomic revision now recognises 10 species with 2 subspecies, with a centre of diversity in Australia. However, character evolution remains unclear along with presumed relationships between individual species. In this study we use extensive sampling of individuals from all recognised species, and infer a species tree phylogeny by using BEAST based on three chloroplast genes (ndhF, trnH and trnLF) and two nuclear regions (ETS and ITS). The analysis indicates a well-supported phylogeny largely conforming to previous assumptions on species groupings that were based on key morphological characters, while at the same time resolving inter-species relationships. Two important evolutionary pathways are distinguished - a shift from woody habit to weedy, and from perennial growth to more annual habits.
Stable isotope dendroclimatology in New Zealand: lessons learned from kauri (Agathis australis) and cedar (Libocedrus bidwillii).
Tom Brookman, Department of Geological Sciences, University of Canterbury, Christchurch, New Zealand
Travis Horton, Department of Geological Sciences, University of Canterbury, Christchurch, New Zealand
Joshua Blackstock, Department of Geological Sciences, University of Canterbury, Christchurch, New Zealand
Jonathan Palmer, Gondwana Tree-Ring Laboratory, Little River, Canterbury, New Zealand
Andrew Lorrey, National Institute of Water and Atmospheric Research Ltd. 41 Market Place, Viaduct Precinct, Auckland, New Zealand
Stable isotopes of carbon and oxygen (δ13C, δ18O) in tree-rings have been shown to provide records of past climate variability. Here we present a 30-year (1981-2010) record of sub-seasonal to annual timescale stable isotopic changes from the southernmost stand of kauri, growing near Dunedin, New Zealand. Produced using novel dual element stable isotope (δ13C, δ18O) low temperature pyrolysis, which greatly reduces analytical time and cost, the record offers insight into the advantages (and pitfalls) of stable isotope dendroclimatology compared with traditional dendroclimatological methods.
We provide replicated measurements of isotopic variability from sub-seasonal to decadal timescales within single trees and between trees within a stand. We also compare kauri isotope data with preliminary data from a nearby stand of cedar, approaching the natural southern limit of that species, to assess inter-species variability in the context of regional climate reconstruction.
We document inter-annual changes of up to 4‰ in δ13C and 7‰ in δ18O. High resolution intra-annual analyses show large, co-varying seasonal patterns for δ13C and δ18O, up to 5 and 8‰ respectively for kauri. The co-variation suggests common climatic and/or physiological drivers and numerous candidates such as temperature, sunshine hours and relative humidity show moderate correlations with δ13C and δ18O. The ability to reconstruct these environmental variables would complement and improve on the current ring-width dendroclimatic archive.
Starting from Scratch: a wish-list for wildlife in the city
Yolanda van Heezik, University of Otago
The structure of cities tends to reflect a historical succession of responses to human needs, with any benefits for wildlife populations being incidental. It is only very recently that the biodiversity existing in urban areas has been acknowledged as having an important role to play in providing ecosystem services, supporting populations of rare species, or enhancing human well-being. However, attempts to improve biodiversity values are constrained by the current reality of urban environments focussed on the infrastructural requirements of the human inhabitants. A major disaster, such as an earthquake, can provide opportunities to start afresh, to create a city better designed to support wildlife. This presentation will discuss features of landscape design at broad (e.g. fragment size, connectivity, matrix structure) and fine (e.g. specimen trees, gardens, roads) scales that have been shown to influence the diversity and structure of urban wildlife communities. The restoration of ecological function requires an integration of both top-down and bottom-up decisions and actions to enable not only the creation of appropriate living spaces for wild creatures, but long-term ongoing active management to protect native species from urban-based invasive pests and predators.
Stictocladius across the southern hemisphere
Matt Krosch, Queensland University of Technology
Peter Cranston, Australian National University
Recognition of the austral midges (Diptera: Chironomidae) as biogeographically significant goes back over half a century. Suggestions that many of these taxa were 'gondwanan' were based originally on similarity, and subsequentl via cladistic analyses. More recent molecular evidence shows some relationships and ages consistent with vicariance dating by gondwanan fragmentation. Others appear younger, especially concerning New Zealand, that preclude vicariance and suggest instead austral dispersal. Having reviewed the morphological taxonomy of the running water genus Stictocladius, we have now undertaken molecular-based analyses to test these relationships, and to allow us to hypothesise the processes that give the current geographic distributions on New Zealand, Australia and the Americas. None of the component clades is monophyletic on a single land mass, and thus we infer more complex relationships than simple gondwanan vicariance of a widespread ancestor.
Stressed and disturbed: experimental eco-restoration in Wairio Wetland, Lake Wairarapa
Stephen Hartley, Victoria University of Wellington
Bridget Johnson, University of Western Australia
Aprille Gillon, Victoria University of Wellington
When water flows from the land to the sea it can redistribute large amounts of sediment and nutrients. For Lake Wairarapa, southern North Island, these processes, coupled with changing land-use practices, have resulted in the lake attaining a “super-trophic” nutrient status. Interest in restoring the surrounding wetland ecosystems has been growing, both for water purification services as well as wider biodiversity values. At Wairio wetlands, this includes a vision to restore 110ha of rough grazing to a mosaic of ephemeral wetland vegetation, including kahikatea “swamp forest”.
To help improve the success and efficiency of the tree-planting restoration efforts, we conducted a field-scale multi-factorial experiment of the most common management techniques used to manipulate a plant’s experience of competition, disturbance and stress. The growth and survival of c.2000 planted trees (including kahikatea, cabbage tree, totora and bush daisy) were monitored for one year. Relatively dry conditions resulted in the best survival for all species, including kahikatea which was the most tolerant of prolonged inundation. Scraping of topsoil was beneficial in dry sites, but had a negative or neutral effect in wetter sites as it encouraged local pooling of water. When attempting to recreate a swamp forest, the more stressful the environment (i.e., the more water-logged the soil) the less need there is to reduce competition from grasses through mechanical or chemical means. Determining the optimum level and mode of intervention required under different environmental conditions has the potential to substantially reduce the labour costs of many eco-restoration schemes.
Subterranean connections: the ultimate phylogeographic tool for Gondwanan biogeography?
William F Humphreys, Western Australian Museum, Collections and Research Centre, Locked Bag 49, Welshpool DC, Western Australia 6986, Australia; and School of Animal Biology, University of Western Australia, Nedlands, Western Australia, Australia; School of Earth and Environm
Ivana Karanovic , Hanyang University, Department of Life Science, Colleague of Natural Sciences, 222 Wanshimni-ro, Seongdong-gu, Seoul 133-791, Korea; University of Tasmania, Institute for Marine and Antarctic Studies, Private Bag 129, Hobart, TAS 7001, Australia
Tomislav Karanovic, Hanyang University, Department of Life Science, Colleague of Natural Sciences, 222 Wanshimni-ro, Seongdong-gu, Seoul 133-791, Korea;
Obligate groundwater animal lineages (stygobionts) have been little explored as phylogeographic tools to understand Southern Connections. This, despite evidence of their persistence in situ through geological eras in terranes subjected to massive geological and climatic changes. Further, stygobiont lineages may persist following contact with other terranes, whereas the epigean fauna may be displaced by the contact fauna. Members of some crustacean groups are obligate subterranean dwellers throughout their life-cycle and many are restricted to freshwater. Most contain species congeneric with those on other Gondwanan terranes, although few of these lineages have yet been tested using molecular phylogeographic analysis. This paper is a primer to facilitate and encourage the necessary intercontinental collaboration to explore this potential. Some higher taxa are especially useful in this regard owing to their high prevalence, broad occurrence, and occasional high numbers in easily sampled groundwaters that have interconnected voids of adequate size for tiny animals (ca 0.3-5 mm) found in many types of matrix. They suffer from small size and consequent poor taxonomic knowledge (one fast improving) and sparse molecular data. Other lineages are unsuitable owing to relatively recent (Tertiary) colonisation of groundwater (e.g., Dytiscidae and Haloniscus: Oniscidea) and still wide representation amongst epigean faunas, or poor diversity on species level, which precludes spatial analysis (Spelaeogriphacea). The paper will outline distributions of some lineages that are considered Gondwanan based on morphological criteria, particularly amongst the Bathynellacea, Ostracoda, Copepoda and Isopoda and discuss comparable analyses from anchialine systems where Tethyan distributions are being tested.
Takahë and the Murchison Mountains, species recovery to ecosystem restoration
James T. Reardon, Department of Conservation
Takahë are a classical species recovery story with over half a century of conservation effort. Rediscovered in 1948, census figures from the 1980s suggested less than 150 takahë remained, these figures spurring research beyond habitat use and reproductive biology, to competitor and predator influences on takahë population biology. Consequently the past 40 years describes the ever broadening implications of managing native fauna in the presence of introduced mammals. From early deer control and captive-breeding efforts to 50,000ha of stoat control and off-shore island management of a takahë meta-population, the attempts to manage takahë in the Murchison Mountains provide a serial lessons in the challenges of managing stochastic processes for species recovery. As efforts have grown in success so they become increasingly engaged in the management of ecosystem-wide drivers of productivity and predation, and grasp the thorny issues of ex-situ management and genetic security, with exciting results.
Rediscovery of takahë stimulated the government of the day to establish the first rare birds advisory committee, which drove early research. More than 60 years later the Murchison Mountains becomes a national priority site for ecosystem management where our focus is shifting to how to apply landscape-wide control of ecosystem drivers such as rodents, whilst monitoring biodiversity responses in a manner unthinkable 60 years prior. With these tools the future of takahë in the Murchison Mountains should be assured, together with a secure and abundant diversity of species not seen on the mainland of the South Island for hundreds of years.
The current conservation status and management of New Zealand’s indigenous grasslands.
Alan F. MARK, Department of Botany, University of Otago, Dunedin, New Zealand.
Kelvin Lloyd, Wildlands Consultants, Dunedin, New Zealand.
Four major New Zealand tussock grassland ecosystems are recognised and four geographic grassland regions in relation to predominant land use. As in most countries, protection increases with altitude. Lower altitude short tussock grasslands are least protected and still undergoing intensive development. Tall red tussock grassland in montane habitats has also been strongly reduced since European settlement in the 1840s and has relatively poor protection. In contrast, montane-subalpine tall snow tussock grasslands are more extensive and have reasonably good protection levels, while alpine snow tussock grasslands are reasonably secure. Degradation of the mostly Government-owned South Island high-country leasehold rangelands is currently being addressed through land tenure review. This involves lease renegotiation to free-hold more productive, usually lower-altitude areas while relinquishing for conservation the more vulnerable usually upper altitude less modified areas. Opportunities to address the serious under-representation of lower altitude grasslands are thus being foreclosed through free-holding and consequent often intensive development. By contrast, important ecosystem services, particularly water production, of upland ex-rangeland are being secured, along with their indigenous biodiversity, landscape, recreational and ecotourism values. Ten conservation tussockland parks, totaling >581,000ha, and other conservation areas have been created to date through this process. Protected grasslands should be secure, yet some ex-rangelands are actively threatened by wilding conifer infestation from old and currently planted nearby stands and coal mining now threatens some unique tussock-wetlands in North Westland. Unprotected short tussocklands on dry, inland basin floors are rapidly being lost to agricultural intensification including irrigation.
The early Holocene westerly wind minimum in New Zealand
Matt McGlone, Landcare Research, Lincoln, New Zealand
The core of the southern westerly winds lies just south of New Zealand over Campbell Island, but a strong westerly influence extends throughout the whole archipelago. Evidence from a number of disparate sources now suggests that between 13 000 and 9000 years ago the core of the westerlies moved some 3-5° southwards to sit over the Antarctic Circumpolar Current. Weakening of the westerly wind field over subantarctic and mainland New Zealand at this time had profound environmental consequences. What have hitherto been regarded as paradoxical aspects of the early Holocene environment, such as low tree lines but frost-free lowlands, ultimately relate to this reduced westerly wind flow situation which has no modern analogue.
The effect of climate and environmental change on the megafaunal moa of New Zealand in the absence of humans
Nicolas J. Rawlence, University of Waikato
Jessica L. Metcalf, University of Colorado
Jamie R. Wood, Landcare Research
Trevor H. Worthy, University of Adelaide
Jeremy J. Austin, University of Adelaide
Alan Cooper , University of Adelaide
New Zealand offers a unique opportunity to investigate the response of extinct megafaunal ecosystems
to major changes in climate and habitat prior to human settlement. Prior to this point (late 13th Century
AD) New Zealand contained a diverse avian megafauna dominated by nine species of large flightless ratite moa (Dinornithiformes). We used ancient DNA approaches to generate mitochondrial DNA sequence data from 39 crested moa (Pachyornis australis) and 145 heavy-footed moa (Pachyornis elephantopus) specimens. In combination with radiocarbon dating and dietary isotope analysis we examined
the effects of Late Pleistocene and Holocene climate and environmental change on the phylogeography, palaeodemographics, and eventual extinction of Pachyornis. We show that Pachyornis changed altitudinal, longitudinal and latitudinal ranges through the Late Quaternary in response to
alterations in the distribution of suitable habitat. However, we found no evidence for large-scale change in population sizes during the past 40,000 radiocarbon years BP (approximately 44,000 calendar years BP), or significant changes in d13C and d15N isotope signatures over this time period. The results suggest that crested moa tracked habitat through time with little consequence to population size. For the more
broadly distributed heavy-footed moa, changes in climate and habitat distribution may have promoted phylogeographic structuring. Overall this study suggests that the likelihood of megafaunal extinction in New Zealand was greatly reduced in the absence of humans.
The fragility of montane C4 grasslands in South Africa
Nick Zaloumis, Botany Department, University of Cape Town
William Bond, Botany Department, University of Cape Town
Grasslands are often viewed as secondary vegetation derived from felling of forests and therefore suitable targets for afforestation. However the montane grasslands of southern Africa are now thought to be ancient, and much more extensive in the last glacial. They are very rich in perennial forb species, many of which have large underground storage organs and seldom recruit from seed. We studied the diversity of pristine grasslands and compared them with restored grasslands after different forms of disturbance, including afforestation and ploughing. Natural succession in restored grasslands failed to restore the diversity of forbs, with very poor recovery even decades after removal of plantation forests. Thus primary grasslands appear to be at least as fragile as primary forests and may take decades to centuries to recover from major disturbance. We explored various methods of restoration to promote the restoration process and discuss results thus far.
The high elevation treeline as a bioclimatic reference
Christian Körner, University of Basel, Switzerland
Upright trees cannot grow beyond a certain elevation and the associated low temperature, globally, provided water shortage is not prohibitive. This bioclimatic threshold for the life form 'tree' separates the alpine belt from the montane belt and represents a most important reference line for any other bioclimatic stratification of biota. Given its tight association with a seasonal mean temperature, this boundary can be modeled and thus, serve as a reference, even in cases where trees are absent because of local disturbance regimes or human land use. In this introductory note, I will briefly present the evidence for the temperature related high elevation tree limit and its physical and biological causes. Statistics will be offered for the global mountain land area and its thermal subunits, based on a treeline model and topographic ruggedness. These data can help positioning biogeographic data in a mountain climatology context. References: Körner C et al. (2011) Alpine Botany 121:73-78; Körner C (2012) Alpine treelines. Springer, Basel
The historical imprint of climatic niche evolution on present day coexistence in New Zealand Coprosma (Rubiaceae)
Kristen Nolting, Michigan State University
Niche theory postulates that species coexist if they differ in one or more axes of niche space. An extension of this hypothesis suggests that species diversification may be the result of adaptation to a range of values along a given niche axis. We use an integrative approach combining environmental niche models with phylogenetic data to investigate the evolution of climatic niches within a radiating plant genus that has undergone astounding ecological diversification. Coprosma (Rubiaceae) contains ~120 species occurring throughout the Pacific with ~55 New Zealand endemics. Species vary tremendously in form and habitat preference, but the degree to which species differ in traits associated with their climatic niche and the relative diversification of these traits through time remains unclear. We hypothesize that radiation into different environments, associated with the evolution of different environmental tolerances, is one of the mechanisms that led to the diversification of this clade. Using twenty-one biologically informative climatic and environmental variables as input in a GIS-based habitat model we quantify niche overlap among species. Additionally, we use disparity plots to evaluate the evolution of climatic niche through time in the genus. Our results show that many variables exhibited less than expected disparity towards the base of the tree followed by recent periods of considerable divergence, and that closely related species differ in several axes of climatic niche.
The impact of Quaternary climate change on the distribution of diversity in Podocarpus elatus (Podocarpaceae)
Rohan Mellick, The Royal Botanic Garden Sydney
A changing climate has caused species to shift in range from ancestral to present-day distributions. The corresponding changes in genetic diversity and structure are known to follow climatic patterns. Linking past intraspecific divergence patterns to well-defined environmental realms of tolerance (e.g. mesic habitats) will allow the forecasting of future threats from likely anthropogenic-induced climate change.
This research aims to determine the level of genetic diversity and structure within naturally occurring populations of Podocarpus elatus, and establish if this is more strongly influenced by historic or contemporary drivers; via (1) environmental niche modelling of the past-current-future distributional dynamics, (2) the observed fossil record and (3) molecular observation and inference.
Using coalescent-based models we estimated population demographic parameters and divergence times between the current genetic disjunctions in the species. The environmental niche models suggest differential range shift will continue into the future (i.e. expansion in the north and contraction in the south), with a southern range shift also occurring in both regions. The isolation-with-migration analysis infers the origin of the Clarence River Corridor, dividing the population groups, to be prior to the last glacial maximum (LGM). A later divergence in the south (19 Ka) is indicative of slow consistent habitat contractions in the south since the LGM (21 Ka).
The future application of molecular and ecological niche modelling techniques could guide the integration of the natural and artificial landscape with the aim of allowing unimpeded range shift in response to rapid climate change.
The impact of temporal environmental instability on the distribution of rainforest diversity
Maurizio Rossetto , National Herbarium of NSW, The Royal Botanic Gardens and Domain Trust
Australian rainforests contain considerable levels of biodiversity despite representing only a small proportion of the continental land-mass. Species distribution and assemblage is dependent on a range of scenarios including environmental filtering that removes the trait combinations that are not capable of sustaining a population, and dispersal limitation where taxa may be absent because they have not yet been able to colonize a site. An important challenge for understanding differences in species survival is to reconstruct temporal changes in population dynamics across diverse co-distributed taxa.
We combine molecular, environmental and functional information to identify the factors that influence the distribution and assemblage of woody species in Australian rainforests. I will present data on community phylogenetic structure across the whole continent that identifies centres of diversity and floristic boundaries. Phylogenetic evenness is more evident in long-term stable habitats (refugia) while clustering is more evident in highly disturbed areas where recolonisation has occurred more recently.
The differential impact of temporal environmental heterogeneity is also notable at the population level. A range of population-based molecular studies (that include traditional markers, coalescent-based analyses, and Next Generation Sequencing approaches) show how historical dynamics and dispersal potential impact on the distribution of individuals and connectivity among populations. Environmental niche modeling of habitat suitability during current and last glacial maximum climatic conditions help us put these patterns within a context of cyclical disturbances.
The islands of Zealandia: some thoughts on discrepancies between the maps of today and maps of the past for explaining modern biota.
George Gibbs, School of Biological Sciences, Victoria University
Although terrestrial life clearly survived on the crustal block of Zealandia throughout its 80 Ma history, there is virtually nothing known of the extent and whereabouts of land and sea, since it separated from eastern Gondwana. Our crucial questions are focussed on the biota of the present islands of New Zealand and New Caledonia and to a much lesser extent the islands of Lord Howe, Chathams, and Subantarctics. The tools available for this investigation are the fossil record, the inventory of phylogenetic case studies that is steadily growing in number and quality, and the prevailing geological interpretations of the entire region. A major limitation is the restriction of our sphere of biological investigation to the 10% of emergent land available today. We look to geological science to reveal relevant hypotheses concerning the remainder of Zealandia. It is time to move on from the inundation debate and to methodically document what we know about the history of land on Zealandia between 80 Ma and the present. A variety of plant and animal studies will be reviewed and discussed that can possibly shed light on this riddle of the SW Pacific. ‘The maps of today hold the records, the maps of the past rationally account for them’, but are we ready to start drawing any maps yet?
The Kelvin wave driven coastal upwelling off Angola
Mare, Institute of Marine Research, Bergen Norway
Bjorn Serigstad, Institute of Marine Research
Although adjacent to the World Ocean’s major wind-driven coastal upwelling system of the Benguela, the Angolan coastal waters owe their productivity to a very different physical mechanism. Stemming from 20 years of concurrent oceanographic and satellite observations, here we present the evidence that the Angolan upwelling is driven by a chain of physical processes initiated by the coastally trapped upwelling Kelvin waves. These seasonal waves, which originate at the equator and propagate down the coasts of Angola in May and December, cause the thermocline to rise. Owing to the shallow thermocline, nutrient-rich South Atlantic Central Water intrudes into the near-shore areas, where it is entrained into the upper layer by means of processes occurring within the water column, such as the breaking of internal solitary and surf-beat waves. The above chains of the mechanism makes the Angolan system quite unique among other fish-rich upwelling systems of the southern hemisphere; as the primary productivity peaks here during the calmest periods, when the upwelling favorable wind forcing is virtually absent.
The Next Generation of New Zealand Floras
Ilse Breitwieser, Allan Herbarium, Landcare Research
Aaron Wilton, Allan Herbarium, Landcare Research
Peter Heenan, Allan Herbarium, Landcare Research
Our goal is to provide a dynamic and continually updated electronically-based Flora for New Zealand. This next generation Flora of New Zealand is aimed at a wide range of users. We are extending the concept of a Flora to include its delivery via a variety of tailored products from books to delivery of different profiles via the internet to smartphone apps. This requires a different, new approach to Flora development. We are developing an information system that allows integration of data from a range of sources. Central to achieving this is the development of processes that allow the capture and analysis of granular, highly linked data to ensure that data used to create the Flora are up-to-date. We have to deal with a number of technical challenges such as efficient processes to capture data linked to specimens, and the development of processes to analyse these data. Also, there are new social and legal challenges such as changing working practices by scientists and the recognition of authorship and copyright. We will present our experiences in developing this new electronic Flora of New Zealand, our planning processes, some of the difficulties we encountered, how work processes of our taxonomists have changed, the lessons we learned, what we have achieved so far, and some of our plans.
The origins and triggers of teleost radiations in the Southern Hemisphere
Michael Matschiner, University of Canterbury, New Zealand
Julia M I Barth, University of Otago, New Zealand
Zuzana Musilova, University of Basel, Switzerland
Walter Salzburger, University of Basel, Switzerland
With over 26,000 living taxa, teleost fishes represent nearly half of the extant vertebrate diversity, including a number of explosive radiations. Some of the most fascinating of these rapidly diversifying groups are found in the Southern Hemisphere. Possibly the fastest radiations take place in the East African Great Lakes, where cichlid fishes have diversified into nearly 2,000 species. Despite numerous phylogenetic investigations, key questions concerning these radiations have yet to be answered. It remains unclear which parts of the cichlid phylogeny are truly exceptional in terms of diversification, and whether specific traits, such as their pharyngeal jaw apparatus, colouration, or breeding behaviour are linked to elevated speciation rates. In another Southern Hemisphere radiation, fishes of the suborder Notothenioidei have diversified into over 130 species on the Antarctic shelves, and evolved a number of exceptional adaptations to the polar environment. Among these adaptations, antifreeze glycoproteins have been proposed as putative key innovation that not only allowed the survival of notothenioid fishes in the ice-cold waters of Antarctica, but also promoted their diversification into unoccupied niches. We here present a new dated phylogeny based on over 1,100 teleost species, over 35,000 bp, and more than 50 fossil calibration points. Bayesian divergence age prior distributions were defined using new models that take into account lineage preservation rate, rock outcrop bias, and fossil age uncertainty. The new time-calibration allows insights into the triggers behind teleost radiations, and highlights the role of oceanic dispersal in the history of freshwater teleost fishes.
The potential of fossils preserved in amber for calibrating the molecular clock: An estimation of the Phanerozoic history of the Ascomycota
Christina Beimforde, Courant Research Centre Geobiology, University of Goettingen
Kathrin Feldberg, Courant Research Centre Geobiology, University of Goettingen,
Hanna Tuovila, Department of Biosciences, University of Helsinki
Jouko Rikkinen, Department of Biosciences, University of Helsinki
Matthias Gube, Institute of Microbiology Friedrich-Schiller-University Jena
Leyla J. Seyfullah, Research Centre Geobiology, University of Goettingen
Heinrich Dörfelt, Institute of Microbiology Friedrich-Schiller-University Jena
Joachim Reitner, Research Centre Geobiology, University of Goettingen
Alexander R. Schmidt, Research Centre Geobiology, University of Goettingen
The phylum Ascomycota is by far the largest group in the fungal kingdom. Ecologically important mutualistic associations such as mycorrhizae have evolved in this group, and are regarded as key innovations that supported the evolution of land plants. While several lines of evidence indicate that fungi are a very ancient group of organisms, few attempts have been made to date the origin and evolution of fungal lineages by using molecular clock models. This is primarily due to the lack of satisfactory fossil calibration data for the Ascomycota. In this study we assembled a data set of four genes (18SrDNA, 28SrDNA, RPB1 and RPB2) from a total of 150 taxa representing all main groups of the Ascomycota. We used a Bayesian approach to estimate divergence times and utilised 11 amber fossils (Aptian to Oligocene in age) to calibrate most of the major lineages in the Pezizomycota (Anziaceae, Caliciaceae, Coniocybaceae, Parmeliaceae and Ramalinaceae for Lecanoromycetes; Laboulbeniaceae for Laboulbeniomycetes; Metacapnodiaceae and Pleosporaceae for Dothideomycetes and Mycocaliciaceae, Trichocomaceae and Venturiaceae for Eurotiomycetes). This is the first study to combine molecular data with all available determinable fossil ascomycetes in order to produce a chronogram with multiple calibration points throughout the Phanerozoic. This demonstrates the great potential of fossils preserved in amber for calibrating molecular clocks.
The resilience of New Zealand pollination systems to changes in the fauna: persistence, replacement, and losses of interactions
Alastair W. Robertson, Massey University
Sandra H. Anderson, University of Auckland
Jenny J. Ladley, University of Canterbury
David E. Pattemore, Plant and Food
Dave Kelly, University of Canterbury
The bird and other vertebrate fauna of the main islands of New Zealand have suffered unusually high rates of recent extinctions and serious declines. As a result, our bird-pollinated plants show some of the highest rates of pollen limitation recorded to the point where regeneration is now also being limited. Fortunately, some offshore islands retain much more intact faunas and offer a glimpse of pre-human pollination conditions. Island-mainland comparisons have highlighted the differences in the network of flower visitors found on these plants and indicate that a qualitative shift of animal species has left some plants without effective pollinators as key species have been lost and not adequately replaced. A guild of shrubs and small trees with moderate nectar rewards have been particularly affected as the nectar needs of the remaining animals are now easily met by a few taller, nectar-rich tree species. Similar shifts appear to have occurred in the seed dispersers and together these changes in ecosystem service threaten to change forest composition unless these mutualisms are properly restored.
The Rhetoric of Engagement: Climate Science and a Word-Weary Public
Professor Dennis Aig, Ph.D., Montana State University
This discussion will focus on why scientists succeed and fail in communicating climate change findings to non-specialist audiences. The Information Age has flooded the public consciousness with so many terms and concepts that useful knowledge often becomes lost in the deluge. Drawing on both U.S. National Science Foundation research studies and journalistic sources, the presentation will define problems in communicating climate change research results and offer some possible solutions.
The role of community groups in wilding management
Andrew Macalister, R&D Environmental
Briana Pringle, Queenstown Lakes District Council
Community groups have an important role to play in the control of wilding conifers in New Zealand. Approximately five large community-led wilding programmes are active in New Zealand, typically working under a charitable trust or incorporated society structure, with governance models that involve a broad range of interest groups, including community and landowner representatives, iwi, Councils and Crown agencies. An unspecified number of smaller community projects are also active, working under a wide range of models. Community groups have proven effective in managing wilding conifer infestations that occur across multiple land tenures and in areas that are valued to the wider community. They generally have clear operational programmes, and are able to access funding and sponsorships that may not be accessible to Council and Crown agencies. Community programmes can lead to greater buy-in from landowners and local agencies, are well-placed to mobilise volunteers, and can be more cost-efficient. Most large community groups are not self-sufficient, and rely on seed funding and/or in-kind support from Council and Crown agencies, the efforts of a passionate leader and the work of unpaid volunteers. Challenges for community groups includes ensuring continuity of funding, especially for maintenance control, and accessing adequate technical and governance support.
The role of diaspore evolution in the transoceanic disjunctions and the invasion into Asia of Roupaleae (Proteaceae).
Sarah Fayed, Plant Sciences University of Tasmania
Tribe Roupaleae (~176 spp., 12 genera, Proteaceae) is distributed across Australia, New Guinea, Asia, New Caledonia, New Zealand and South and Central America. The most recent age estimate for Roupaleae is ~63Ma, and during this time the landmasses in its contemporary distribution have undergone significant tectonic movement, marine submergence and aerial orogensis. Current molecular phylogenetic inferences for Roupaleae show the relationships between genera are not well supported, and this is not improved in morphological studies. Previously this group has been unsuitable for testing biogeographic hypotheses. We rectify this by strengthening the inferences of temporal, phylogenetic, and geological constraints on the tribe, and then test whether diaspore evolution is uncorrelated with biogeographic disjunctions. We do this by i) revising the phylogenetic estimates with new taxa and six DNA fragments some of which are new to Proteaceae studies; ii) constraining this estimate with four fossil calibration points; iii) reviewing the current tectonic evolution theory of the region; iv) using this information to age disjunctions and categorize them as either vicariant or dispersal events; iv) and finally by assembling a morphological data set for diaspores, to assign diaspores to a dispersal syndromes, and test whether diaspore syndrome is uncorrelated vicariant and dispersal events.
The role of Local Government in managing Wilding Conifers and supporting related research in New Zealand
Richard Bowman, Environment Southland
Local Government agencies, including Regional Councils and District Councils, are responsible for the sustainable management of natural resources under the Resource Management Act 1991 in the areas they administer. They may also manage the impacts of harmful organisms by approving pest management strategies under the Biosecurity Act 1993. The legislation provides a rationale and tools to manage wilding conifer spread but does not require this activity to undertaken.
Despite the fact that many local Government agencies face similar wilding conifer issues and have the same regulatory tools a wide variety of responses have been adopted across New Zealand. The lack of coordination between Local Government and other agencies arises from a number of geographic, political, social and cultural factors. This diversity creates problems for management across landscapes because wilding conifers have no respect for political or administrative land boundaries.
This paper examines the current application of some regulatory tools by Local Government agencies to manage wilding conifer spread. It also considers the benefits that would accrue from better national co-ordination of the policy and operational management for wilding conifer management. The importance of research and development to enable more effective and efficient management of wilding conifers and the role of Local Government in this activity is also discussed.
The Southern Ocean as a barrier to north-south dispersal: lessons from biological range shifts with past climate change in the Southern Hemisphere
Ceridwen Fraser, Australian National University
There is naturally a growing interest in how future climate change will affect the distributions and survival of organisms. Understanding how past climate change has affected organisms can give us insights into the capacity of various species to shift their distributional ranges in response to ongoing, anthropogenically-accelerated global warming. Using genetic techniques, many studies are now assessing patterns of postglacial range changes (e.g., postglacial recolonisation of areas affected by glacial ice or sea ice during the last Ice Age) that have occurred for many species since the Last Glacial Maximum, approximately 18-20 thousand years ago. Intiguingly, emerging data suggest that general patterns of postglacial range changes in the Southern Hemisphere have been considerably different to those observed for the Northern Hemisphere biota, apparently as a result of geographical differences in the high latitudes of the hemispheres. In this talk, I will summarise the patterns of postglacial range changes observed for taxa in the high latitudes of the Southern Hemisphere, highlight differences between these and patterns noted for the Northern Hemisphere biota, and discuss new research directions that could improve our understanding of how Pleistocene glacial-interglacial cycles have affected Southern Hemisphere organisms. I will also outline the inferred role of the Southern Ocean in preventing north-south dispersal of many organisms, and discuss how strong ocean currents such as the West Wind Drift / Antarctic Circumpolar Current have nonetheless allowed some taxa to achieve broad-scale postglacial recolonisation of southern landmasses via trans-oceanic dispersal.
The Southern Ocean – responding to past and present change.
Lionel Carter, Antarctic Research Institute, Victoria University
The Southern Ocean occupies a unique position in the Earth ocean/climate system. A lack of landmass has meant that the ocean has behaved in a relatively self-regulated manner with strong connections with climate. The former is dominated by a series of fast flowing, turbulent fronts that form the Antarctic Circumpolar Current (ACC). This is the “greatest flow on Earth” being the longest, largest current and the only one to connect the major ocean basins. This west to east, wind-driven flow interacts with north-south overturning circulations that distribute intermediate and abyssal depth waters along with their heat, salt, gases and nutrients into the Northern Hemisphere. Both the ACC and overturning circulations formed from the break-up of Gondwana. They are thus are long established phenomena with the abyssal currents forming ca. 34 million years ago and the surface flows much earlier. Unsurprisingly, the circulation has fluctuated throughout time due to plate tectonic control of seaways and glacial-interglacial climatic cycles. Recent oceanographic and climatic observations show that the Southern Ocean is again responding, this time to a climate forced by excessively high green-house-gasses. Ocean freshening and warming, sea level rise, poleward shift of westerly winds and southward expansion of the subtropics, are but some of the changes underway. Such observations highlight the processes of change, and when integrated with past ocean/climate reconstructions that reveal the ultimate effects of change, we are better equipped to identify the likely response of the Southern Ocean to modern warming.
Too hot out there! Let’s hide in the forest!
Carla Piantoni, Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão Tr. 14 No. 321, CEP 05508-900 São Paulo, SP, Brasil
Nora R. Ibargüengoytía, Departamento de Zoología, Laboratorio de Ecofisiología e Historia de Vida de Reptiles, Centro Regional Universitario Bariloche, Universidad del Comahue; e INIBIOMA–CONICET, Universidad Nacional del Comahue, Quintral 1250, San Carlos de Bariloche, Rı´o Negro 8400, Argentina
Carlos A. Navas, Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão Tr. 14 No. 321, CEP 05508-900 São Paulo, SP, Brasil
Tropidurus torquatus (Squamata: Tropiduridae) has been assessed as Least Concern by the UICN due to its large distribution, insufficient widespread threats and insignificant population declines. In southern Brazilian Cerrado the species is commonly found thermoregulating in anthropic environments, particularly on walls, while in the northernmost localities they are mostly restricted to gallery forests and replaced in the urban microhabitats by T. oreadicus. In order to understand this divergence in habitat selection by T. torquatus we collected body (Tb), microenvironmental (Ta), and operative (Te) temperatures in three sites along a latitudinal gradient during the reproductive season: a southern and a central sites where the species inhabits urban areas and one northern site where it occurs in the gallery forest and T. oreadicus occurs in urban microhabitats. All three populations of T. torquatus present similar Tb (35.99, 35.5 and 35.7 °C, respectively) and shared a similar Ta that ranged between 34 to 37.3 °C. T. oreadicus´ Tb was 38.2 °C and Ta ranged between 30.5 to 42.3 °C. Operative temperatures between sites in the northernmost region showed lower temperatures in the gallery forest and low availability of suitable Ta for T. torquatus, explaining its limited distribution in this locality. The overlap between Tropidurus’ Tb, Ta, and Te highlights a low margin for activity under thermal environment changes that may preclude time of activity and possibly drive some populations to extinction. Devastation of natural microhabitats and the gradual global warming may spread the pattern southwards, representing an alarming scenario for the species.
Tools needed from long-term records to feed people and birds.
Malika Virah Sawmy, WWF
Conservation areas in the Southern Hemisphere are the loci of land clearing for agriculture, which represents the chief cause of the loss of plant and animal species. As demands for food are ever increasing at a rate never seen before, these conservation areas are unable to withstand the intrusion of hungry people or commercial farms seeking land on which to grow crops or graze their cattle. How can the long term records help in better balancing production with conservation? What practical application does the science of thresholds, triggers, drivers and resilience hold for balancing these two critical needs? Here, we use two specific ‘deforestation’ drivers, livestock production and family farms in Africa and Madagascar and palm oil production in Indonesia to examine how the long term records can help balance these objectives in practical ways and argue here that better tools are needed from long-term scientists for changing the paralysis of mentalities, in which both conservationists and farmers find themselves.
Towards a natural classification of Chrysophylloideae (Sapotaceae) in Oceania and Southeast Asia based on nuclear sequence data
Ulf Swenson, Swedish Museum of Natural History
Stephan Nylinder, Swedish Museum of Natural History
Jérôme Munzinger, IRD, UMR AMAP, Montpellier
Generic limits within subfamily Chrysophylloideae (Sapotaceae) from Oceania and Southeast Asia, with New Caledonia in focus, are reconciled based on a molecular phylogeny. We analyzed sequences of nuclear ribosomal DNA (ETS, ITS) and the nuclear gene RPB2 with BEAST and parsimony jackknifing, using a sample of 167 terminals. Eight morphological characters were traced on a condensed majority-rule consensus tree to identify diagnostic character combinations for the genera. Accepted genera with character support are Beccariella, Magodendron, Pichonia, Planchonella, Pycnandra, Sersalisia, and Van-royena, while Niemeyera requires amendment. Beccariella is a widely distributed group, but the name is an illegitimate later homonym and we propose that the genus Pleioluma is resurrected in its place. The Australian genus Niemeyera is paraphyletic, but is rendered monophyletic by reinstating Amorphospermum for N. antiloga. Beauvisagea, Blabeia, Fontbrunea, and Krausella are all segregates of Planchonella and rejected, while Wokoia is a later synonym of Pichonia. Planchonella baillonii is the sole member of a lineage and firmly placed as the sister to a clade comprising the other congeners. Planchonella sandwicensis, a Hawaiian species, proposed to be a distinct genus, is a member of Planchonella. In the Pacific, P. tahitensis (= P. grayana) is a polymorphic species, widely distributed and adapted to a wide range of habitats. We provide a diagnostic character combination for each genus and the necessary fifty taxonomic combinations for Pichonia, Planchonella, Pleioluma, and Sersalisia to render each genus monophyletic.
Towards the conservation and sustainable management of temperate grasslands: a South African perspective
Clinton Carbutt, KZN Wildlife
This paper provides an overview of the gains achieved for temperate grassland conservation in South Africa. It details the successes in proclaiming new temperate grassland protected areas through the Biodiversity Stewardship Programme since its inception in 2006, and explores the funding model used to increase the number of stewardship facilitators which is often the key limiting factor impeding the rate at which these grassland protected areas are proclaimed. Furthermore I detail the need for enabling partnerships given the increasing constraints on government funding and conclude with mainstreaming initiatives aimed at ensuring buy in from both policy makers and production sectors through the “making the case” messaging for temperate grassland biodiversity. All such interventions are aimed at increasing the levels of protection and sustainable use of this beleaguered and poorly conserved biome.
Towards the creation of an integrated system of protected areas in Chile
Francisco A. Squeo, Universidad de La Serena, Institute of Ecology and Biodiversity (IEB) and Centro de Estudios Avanzados en Zonas Aridas (CEAZA), La Serena, Chile
Carlos F. Gaymer, Universidad Católica del Norte, Institute of Ecology and Biodiversity (IEB) and Centro de Estudios Avanzados en Zonas Aridas (CEAZA), Coquimbo, Chile
Karina Martínez-Tillería, Universidad de La Serena, Institute of Ecology and Biodiversity (IEB) and Centro de Estudios Avanzados en Zonas Aridas (CEAZA), La Serena, Chile
Chile is committed to extending its National System of Protected Areas (NSPA), focusing on eco-regions whose ecosystems are currently under-represented in the NSPA. A new proposed law aims to create a Service of Biodiversity and Protected Areas that would unify the terrestrial and marine systems. The proposed law would allow the inclusion of private protected areas. We evaluate the current status of the conservation areas and propose an eco-regional plan that would allow reaching the overall target to bring 10% of all natural ecosystems under protection. A GAP analysis for all Chilean terrestrial and marine environments considered two protection scenarios: (1) public protected areas only, and (2) a combination of public and private protected areas. Afterwards, a multi-scale MARXAN assessment including 1,367 conservation objects was carried out. Chile does not meet its conservation target in four out of its 11 terrestrial eco-regions and in one of its eight marine eco-regions. To achieve the target of having 10% of all natural ecosystems (and other subordinate conservation objects) under protection, an expansion of terrestrial public and private protected areas that currently cover 21.4% of Chile is required to reach 37.5%; marine protected areas need to cover 11.8% of Chile’s exclusive economic zone. The underrepresented conservation objects in the highly bio-diverse Mediterranean region require a pro-active strategy of private protected areas.
Trophic interactions in a waterscape context: embracing the meta-ecosystem concept for freshwater conservation
Angus McIntosh, University of Canterbury
Conservation in radically changing ecosystems poses a huge challenge. The magnitude of the task is highlighted by the contingent nature of biotic interactions. This is especially true of freshwater ecosystems where environmental context controls the outcome of interactions, and cross-ecosystem flows of energy are also highly influential. Embracing a meta-ecosystem approach will help meet this context-dependency challenge. Firstly, by putting food webs in a landscape context, the approach emphasises spatial and temporal dynamics. For example, the distribution of native galaxiids in trout-invaded Canterbury streams depends not only on the spatial location of trout-free galaxiid source populations, but also on the habitat size of sink patches. Moreover, by considering fluxes of energy that are usually the domain of ecosystem ecologists, the approach produces a wider breadth of understanding. For example, populations of Dolomedes fishing spiders are controlled by both the availability of habitat in the terrestrial environmental and the supply of energy from the aquatic environment, both of which depend on stream disturbance regimes. Similarly, in a system intimately linked to the surrounding South Westland rainforest, pool-dwelling brown mudfish populations are controlled by a delicate balance between subsidy flux from the forest and habitat-drying which eliminates their competitors. Finally, the approach also helps focus management. In lowland Canterbury streams subject to intensive agriculture, habitat size is a major controller of stream condition. This isn’t surprising since small habitats are most susceptible to cross-ecosystem exchanges, but it highlights the need for management efforts in small streams.
Updating the dating: How old is New Caledonia biodiversity?
Grandcolas Philippe, UMR 7205 CNRS Museum national d'Histoire naturelle
Roseli Pellens, UMR 7205 CNRS Museum national d'Histoire naturelle
Tony Robillard, UMR 7205 CNRS Museum national d'Histoire naturelle
Frédéric Legendre, UMR 7205 CNRS Museum national d'Histoire naturelle
André Nel, UMR 7205 CNRS Museum national d'Histoire naturelle
Louis Deharveng, UMR 7205 CNRS Museum national d'Histoire naturelle
New Caledonia is an island biologically very rich and diverse. It was long considered as a “Gondwanan refuge” harboring many old species and diversifications the origin of which can be traced back to vicariance with Australia 80 My ago. The rise of molecular and geological studies independently suggested a history of long Eocene submersion in discordance with this previous "Gondwanan refuge" paradigm. The time is ripe now for a meta-analysis of molecular datings which were made since one decade. We thus conducted such an analysis which brought interesting and clear results concerning the origin of New Caledonian biota.
Urban Change Ecology
Glenn H Stewart, Lincoln University
Colin D Meurk, Landcare Research
Wayne C Zipperer, USDA Forest Service
Urban environments are key to the future of human-kind in terms of commerce, importance of green space to health, happiness, equity and productivity, to lowland biodiversity, and lessons on limits to growth and sustainability. In this presentation we review current knowledge of urban change ecology, the nature of chronic and catastrophic disruption, and the mechanisms of, and management for living and recovering within the context of dynamic physical, social and biological systems. Consideration of urban resilience to disasters is a very important and timely topic given all the recent prevalence of earthquakes, fires, floods, tsunami’s, and dust storms that have occurred, particularly around the Pacific Rim in the past few years. Urban ecology was born out of the debris of WW11 in Europe with Sukopp and others who studied post-disturbance vegetation change. Since then vegetation of urban environments has been typified, the relationships between plants and animals and urban environments explored, bio-socio-cultural and economic interactions of cities investigated, and the values of biodiversity to the provision of ecosystem services and human health recognised. It has become a reality that we are experiencing global warming and the climate is becoming more unpredictable. In this presentation we focus on the ecology and biodiversity of natural disasters and how these might affect cities. We use examples from recent earthquakes, hurricanes, and shrinking cities to describe primary/disturbed sites, new plant successions, and new dynamics between vegetation, invertebrates, birds and mammals.
Urban forest of residential Auckland: variation in structure, composition and resilience
Sarah Peters , School of Biological Sciences University of Auckland
Bruce Burns, School of Biological Sciences University of Auckland
Urban forests enhance both biodiversity values and human quality of life. Despite these important roles, the characteristics of urban forest within residential gardens are not well known, even though these areas constitute a major component of urban green space. We measured the composition and structure of urban forest within 66 residential gardens on the North Shore, Auckland, and analysed variation in these against section size, suburb age and proximity to native forest fragments. The North Shore urban forest had high levels of species richness and high beta diversity. Although most exotic species are rare, they dominate the garden flora. Important structural characteristics of this forest include low tree density, low canopy height, a high proportion of small, multi-stemmed trees, and a lack of large individuals. The newest suburbs contain fewer weeds, smaller trees and a higher density of native stems. No significant effect was detected in the composition of the urban forest in relation to proximity to native forest fragments. Larger sections–with an increased area and proportion of green space–contain more plant species, a higher basal area, and include larger and taller trees than smaller sections. This key finding implies that continuance of the current trend towards more intensively developed residential areas with smaller section size and lower proportions of green space per section will lead to a reduction in the size and species richness of the urban forest, resulting in reductions in its resilience and associated environmental benefits. Such changes must be of concern to urban planners.
Using agent-based modelling to explore the dynamics of megafaunal extinctions
George Perry, University of Auckland, New Zealand
David O'Sullivan, University of Auckland, New Zealand
Jamie Wood, Landcare Research, New Zealand
Janet Wilsmhurst, Landcare Research, New Zealand
Human-environment interactions are reciprocal - while human activities change the environment, human actions are, in turn, constrained by those changes. There is increasing use of models to explore the dynamics of prehistoric megafaunal extinctions. Approaches, such as static species distribution models and dynamic population models, cannot, however, represent the reciprocal nature of human-environment interactions. Instead they simply represent human actions as external forcing factors. Agent-based models (ABMs) represent the interactions between individual 'agents' and their environments. In ABMs agents are autonomous, goal-seeking entities such as individual humans or small groups occupied in the same activity. These agents can change both their environments, for example via resource exploitation, and their own behaviour, in response to environmental changes. ABMs, therefore, have the potential to allow exploration of the dynamics of prehistoric ecosystems in ways that more traditional approaches cannot. We will describe the potential utility of the agent-based approach by presenting a prototype ABM of foraging/hunting by a small group of people landing on an island and exploiting resources of different values. The settlers seek to meet their needs by the acquisition of low value, but plentiful resources, and hunting for high-value, but rare and patchy, resources. The model produces a range of outcomes, all more or less compatible with known settlement histories, and allows us to evaluate the extent to which the extinction of island megafauna, such as moa, was inevitable once hunting began.
Using ancient dung to learn about the ecology of extinct species
Jamie R. Wood, Landcare Research
Janet M. WIlmshurst, Landcare Research
Late Quaternary coprolites (ancient dung) contain a wealth of information about the ecology of extinct species, and can reveal aspects of diet, habitat use, seasonal movements, and health. Moreover, by analysing multiple coprolites from one locality inferences can be made about niche partitioning, community structure, and sex-dependent variations in diet. In this talk we will highlight lessons learnt from studying coprolites of New Zealand’s extinct and rare birds. In particular, these lessons relate to where coprolites preserve, how they can be analysed, what coprolite analysis can tell us about the likely wider ecological implications of faunal extinctions, and how coprolite studies may be able to assist with conservation of rare species.
Variability in the position of the mid-latitude westerlies during the mid to late Holocene: insights from Australian dust emissions
Samuel Marx, GeoQuEST Research Centre - School of Earth and Environmental Sciences, University of Wollongong, Wollongong, New South Wales, 2522, Australia
Hamish McGowan, Climate Research Group, School of Geography, Planning and Environmental Management, The University of Queensland, St Lucia, Queensland, 4072, Australia
Balz Kamber, Department of Geology, School of Natural Sciences, Trinity College Dublin, Dublin 2, Ireland
Variability in the strength and position of the mid-latitude westerlies over Southern Australia is interpreted using rates of long-range Australian-sourced dust deposited in mid-Holocene-aged alpine peat cores collected from sites in the Snowy Mountains, Australia and from central Otago, New Zealand. Dust deposition rates were calculated using a trace element model which allows long-range dust deposition into the peat bogs to be separated from local dust or fluvial input. In addition, the Australian provenance region of the dust was able to be determined using the same approach. Periods of reduced dust transport from southern Australia were interpreted to imply increased persistence/penetration of south-westerlies over the continent resulting from increased advection of moisture, with dust entrainment inhibited due to increased soil moisture and vegetation cover. Low dust deposition from 6500 to 5500 cal. BP occurred during a period of enhanced south-westerly winds. A period of sustained dust activity from 5500-4000 cal. BP was interpreted as a relaxation in south-westerlies resulting in a more arid phase and possibly enhanced climate variability. Reduced dust deposition between 4000 and 2000 cal. BP implied a return to increased precipitation/moisture in south-eastern Australia associated with increased south-westerly geostrophic flow. This coincided with increased discharge in the Murray River and cooler conditions in the Snowy Mountains. The onset of more arid conditions after 2000 cal. BP suggested a reduction in the frequency of precipitation bearing south-westerly winds, with further minor dust pulses occurring coincident with drier conditions in southern Australia during the Little Ice Age.
Variance and covariance of traits in plant species across abiotic gradients in the sub-Antarctic Kerguelen Is. and significance for adaptive potential
Françoise Hennion, UMR 6553 Ecobio, CNRS, Université de Rennes 1, Rennes, France
Marie Hermant , UMR 6553 Ecobio, CNRS, Université de Rennes 1, Rennes, France and FRE CNRS 3268 GEPV, Université des Sciences et Technologies de Lille 1, France
Richard Winkworth, UMR CNRS 6553 Ecobio, Université de Rennes 1, France and IMBS, Massey University, Palmerston North, New Zealand
Philippe Vernon, UMR 6553 Ecobio, CNRS, Université de Rennes 1, Station Biologique de Paimpont, France
Peter Convey, British Antarctic Survey, Natural Environment Research Council, Cambridge, UK
Andreas Prinzing, UMR CNRS 6553 Ecobio, Université de Rennes 1, France and Alterra Centre for Ecosystem Studies, Wageningen University and Research Center, The Netherlands
Climate is rapidly changing in the sub-Antarctic islands and plant populations face the threat of extinction. This can be avoided if populations move to favourable habitats, organisms successfully overcome stressful conditions via plastic changes, or populations undergo evolutionary adaptation. However, in spatially isolated sub-Antarctic island environments dispersal will mostly not be achievable, leaving the main role to plastic changes and/or adaptation. Currently, very little is known about either plastic responses to abiotic environmental changes in sub-Antarctic plants or their potential to adapt to such change. Exploring the realized phenotypic variability of species in relation to environmental gradients provides a means to examine the responses of plants to real environments over large scales. Furthermore, comparing response patterns between endemic and more widely distributed or invasive species could help elucidate the importance of adaptation in nature. We studied the variability of traits in plant species across environmental gradients in the sub-Antarctic Kerguelen Islands. We measured morphological, phenological, ecophysiological and metabolic traits. Along each gradient we measured water saturation, pH and conductivity in the soil, and temperature. We tested the effect of environmental variables on trait values and examined correlations between traits (i.e., phenotypic integration and its variation). Across environmental gradients phenotypic integration was significantly correlated to the endemism level of species. Initial data also indicate that many biogenic amines present in plant leaves share this relationship. These results are interpreted in terms how trait variation in endemic and non-endemic species contributes to an ability to face changes in abiotic conditions.
Variation in pregnancy rates across time and space in a cool-climate lizard: is there a relationship with temperature?
Alison Cree, University of Otago
Sophie Penniket, University of Otago
Stephen C. Adolph, Harvey Mudd College
Jane E. Girling, University of Melbourne
Kelly M. Hare, Victoria University of Wellington
Jennifer Rock, University of Otago
Ectotherms have the potential to be profoundly affected in their reproductive rates and other life-history characteristics by climatic conditions, especially temperature. A prime candidate species from southern New Zealand is the viviparous gecko Woodworthia ‘’Otago/Southland” (previously Hoplodactylus maculatus). Studies from the early 1990s at a mid-elevation site at Macraes Flat (500-720 m asl) revealed an unexpectedly low pregnancy rate (only about half the females entered pregnancy in summer), a pattern attributed to cooler summer conditions than at lower-elevation sites. Here, we analyse a 20-year data set for geckos at Macraes Flat to determine whether pregnancy rates, body size or clutch size have changed since the early 1990s and, if so, whether changes over time can be explained by changes in temperature. We find no significant evidence for a shift to annual reproduction. However, a separate analysis of pregnancy rates across multiple sites (54–1039 m asl) in 2010 shows significant spatial variation in relation to temperature: although there was one notable exception, sites with warmer summers generally have higher proportions of females entering pregnancy. We use these data, combined with current rates of warming, to predict when geckos at Macraes Flat or higher elevations should shift to annual reproduction and if so, whether body size and clutch size would be expected to change. Finally, we consider whether such shifts in life history are likely to be advantageous or not, given other possible outcomes from global climate change.
Water and sediment quality of Campbell Island
Shelley McMurtrie, EOS Ecology
Alex James, EOS Ecology
Peter Robinson, Hill Laboratories
In December 2010, 200 years after its known discovery, the Campbell Island Bicentennial Expedition spent nine weeks on Campbell Island uncovering its human history, ecosystem processes and ecology, and biota recovery from decades of grazing and the world’s largest eradication programme. As part of this expedition EOS Ecology undertook the most comprehensive sampling programme for the island’s streams and tarns, which included water and sediment quality. Water samples were analysed for 36 parameters, including anions, cations, seven nutrients, and 15 dissolved metals. Sediment samples were analysed for 37 parameters, including organic carbon, nitrogen, and 33 metals. Water and sediment quality were affected by the underlying geology, but also by exposure to coastal wind-blown spray and the presence of marine animals. The more interesting sediment and water quality results and patterns will be presented and how this relates to nutrient dynamics and marine subsides, along with an insight to the challenges of sampling on such a remote island.
Westerly driven vegetation and fire regime shifts at centennial timescales in southwestern Patagonia (52°S) over the last 3000 years
Patricio I. Moreno, Institute of Ecology and Biodiversity
Isabel Vilanova, CONICET-Museo Argentino de Ciencias Naturales, Buenos Aires, Argentina
Rodrigo Villa-Martínez, Modern and paleoclimate perspectives on the Southern Hemisphere westerly wind fieldCentro de Estudios del Cuaternario (CEQUA) Avenida Bulnes 01890, Casilla 737, Punta Arenas, Chile
Twentieth-century instrumental records reveal a persistent southward displacement and intensification of the Southern Westerly Winds (SWW) contemporaneous with steady increases in atmospheric temperatures and CO2 concentrations, glacial recession at a global scale, and a positive phase of the Southern Annular Mode (SAM). To date it is unclear whether this mid-latitude atmospheric phenomenon represents natural variability or a response to human-induced climate perturbations. Here we present a paleovegetation and paleofire record from Lago Cipreses (51°S), southwestern Patagonia, that reveals periodic ~200-yr long droughts since 3000 cal yr BP. The most recent of these events started in the 19th century and has persisted until the present, concomitant with positive anomalies of the SAM and widespread disturbance of southwestern
Patagonian environments by Euro-Chilean settlers. We identify nearly identical shifts during the Late Bronze Age, Roman and Medieval Warm Periods, and between 1600-1400 cal yr BP, which we attribute to positive anomalies of the SAM. These alternate with humid phases which coincide in timing with the Iron Age and Dark Ages cold periods, and the Little Ice Age. We propose that the SWW varied in concert with important temperature anomalies in the Northern Hemisphere over the last 3000 years, with positive SAM-like changes corresponding with warm episodes, and vice versa, and conclude that the current poleward shift and intensification of the SWW reflects juxtaposition of natural and human-induced variability since the 19thcentury, providing a potential source of future climate variability through alterations of the ocean-atmosphere exchange of CO2 at high southern latitudes.
What is the long-term role of fire in the dynamics of long-lived southern conifer plant communities? A case study from southern Tasmania
Michael-Shawn Fletcher, The Australian National University; Institute of Ecology and Biodiversity, Chile.
David MJS Bowman , The University of Tasmania, Australia
Simon G Haberle, The Australian National University, Australia
David P Pompeani , The University of Pittsburgh, USA
Cathy Whitlock, Montana State University, USA
Brent B Wolfe, Wilfrid Laurier University, Canada
Fire is a key ecological agent that has been implicated in the determination vegetation patterns at scales ranging from local to global. Despite this recognition, there is a critical lack of empirical data pertaining to important facets of the relationship between fire and vegetation, such as long-term fire-return intervals and effects of fire on species compositions and soil nutrient capital. This is particularly the case for slow-growing and long-lived vegetation systems, such as southern hemisphere temperate conifer forests, where our current understanding of vegetation-fire interactions is largely underpinned by spatio-temporal substitutions and which have suffered devastating effects from post-colonial wildfires. A case-in-point is the landscape-scale loss of forests dominated by the iconic King Billy Pine (Athrotaxis selaginoides D. Don [Cupressaceae]), resulting from fires lit during exceptionally dry years between 1960 and 1980. A. selaginoides is a slow-growing and apparently fire-sensitive conifer that lives for over 1000 years. Regeneration and/or recruitment has not yet occurred at burnt sites and it is unknown whether these systems can and/or will recover from these catastrophic wildfires. This paper presents the results of a fine-scale multi-proxy palaeoecological reconstruction from Lake Osborne, southern Tasmania (43°12’53”S, 146°45’30”E), a high-altitude lake (915 masl) with a gently sloping and very small catchment that displays the clear effects of fire and which is host to A. selaginoides. These site characteristics favour a localised sediment signal and I employ pollen, charcoal, geochemical and magnetic analyses to reconstruct decadal to centennial-scale dynamics within the catchment over the last 6500 years.
What kind of relict is Amborella trichopoda in New Caledonia?
Philippe Grandcolas, UMR 7205 CNRS Museum national d'Histoire naturelle
Thomas Haevermans, UMR 7205 CNRS Museum national d'Histoire naturelle
Margaret Evans, UMR 7205 CNRS Museum national d'Histoire naturelle
Jérôme Munzinger, UMR AMAP CNRS IRD 34398 Montpellier cedex 5
Peter Porter Lowry, UMR 7205 CNRS Museum national d'Histoire naturelle
Roseli Pellens, UMR 7205 CNRS Museum national d'Histoire naturelle
One of the most remarkable relict species in the world is Amborella trichopoda in New Caledonia. This plant species, the sole living representative of the family Amborellaceae, is sister-group to all other flowering plants according to the most recent phylogenetic studies. Its presence in New Caledonia has often been interpreted as a strong indication of the permanence of terrestrial biota of the island since 80 My ago. This reasoning is based on a misunderstanding about the very nature of relicts, which are frequently seen as living ancestors when they are only survivors of large groups mainly extinct. Therefore, they can actually be old or recent species, ancestrally present in a place or not. These two different cases imply species that remain a long time specialized on an undisturbed stable niche versus tramp species that are able to deal with many environments and to survive. We analyse the bioclimatic niche of Amborella trichopoda to distinguish among the two possibilities by confronting this niche to the whole bioclimatic domain available in New Caledonia.
When did New Zealand's terrestrial vertebrates evolve?
Alan J.D. Tennyson, Museum of New Zealand Te Papa Tongarewa
R. Paul Scofield, Canterbury Museum, Rolleston Avenue, Christchurch, New Zealand
Trevor, H. Worthy, School of Earth & Environmental Sciences, University of Adelaide, Adelaide, South Australia, Australia
A wealth of new fossil and molecular research has greatly increased our knowledge of the origins of New Zealand's unique terrestrial vertebrate fauna. Evidence indicates that the ancestors of some taxa evolved earlier than suspected, e.g. stitchbirds (Notiomystidae), while others evolved later than previously believed, e.g. Haast's eagle (Aquila moorei). A divergent range of taxa appear to have their origins on Gondwana, i.e. NZ frogs (Leiopelmatidae), tuatara (Sphenodontidae), moa (Dinornithiformes), adzebills (Aptornithidae), large parrots (Strigopidae) and NZ wrens (Acanthisittidae), and possibly NZ geckos (Diplodactylinae). However the ancestors of the majority of taxa arrived over-water since Zealandia's separation from Australis. Evidence supports a pre-Oligocene origin for the majority of other well-differentiated taxa, e.g. kiwi (Apterygidae), several waders (Coenocorypha, Anarhynchus, Thinornis), NZ wattlebirds (Callaeidae), stitchbirds, piopio (Turnagridae), the Mohouinae songbirds, NZ honeyeaters (Anthornis, Prosthemadera) and short-tailed bats (Mystacinidae), and possibly NZ skinks (Oligosoma) and NZ pigeons (Hemiphaga). The ancestors of other taxa arrived in the Miocene or later, e.g. Haast's eagle, weka (Gallirallus australis), tomtits and robins (Petroica) and long-tailed bat (Chalinolobus tuberculatus); including several after humans settled, e.g. swamp harrier (Circus approximans), swamphen (Porphyrio melanotus) and silvereye (Zosterops lateralis). These findings are roughly in accord with earlier biogeographic theories, although in the past the antiquity of taxa tended to under-estimated. There is little to suggest that the Oligocene "drowning" resulted in widespread extinctions but for some taxa, e.g. skinks, the fragmentation of landmasses and habitats during the Oligocene low-stand may have driven speciation events.
Where are we with wilding conifer management in New Zealand?
Nick Ledgard, Retired Scion scientist
Victoria Froude, Pacific Eco-Logic Ltd, Bay of Islands, New Zealand
Introduced conifers grow well in NZ, and comprise 98% of commercial plantation forests which occupy 1.8 million ha (6% of land area). In 2007 various densities of wilding conifers, affected about 805,000ha in the South Island and about 300,000ha in the North Island. Wilding conifers threaten conservation, visual landscape, pastoral farming and hydrological values. Some of the worst infestations are associated with ongoing spread from early/legacy plantings, often by Government agencies.
Current control expenditure is over NZ$5m annually by central government agencies, and between NZ$0.5-1m by local government. A number of community trusts undertake localized control. While there have been some significant control successes, public agencies have insufficient funding for effective long-term control, and wildings continue to spread in many areas. Government funding for wilding control is severely constrained and may be further reduced. This situation is exacerbated by conflicting (although often unintended) policy intentions, coupled with variable implementation.
In 2007 a multi-stakeholder Wilding Conifer Management Group was established to oversee and contribute to a publically funded research programme on wilding conifers. This Group subsequently contributed to the preparation of a national wilding status report and endorsed the report’s recommendations. The report’s key recommendation-that a national non-statutory wilding conifer strategy be prepared- has been agreed by the relevant Government Minister.
Who wins when north and south collide – the historical dynamics of intercontinental floristic exchange across Wallacea
Darren M. Crayn, Australian Tropical Herbarium, James Cook University
Craig Costion, Australian Tropical Herbarium, James Cook University
Mark Harrington, Australian Tropical Herbarium, James Cook University
Since the collision of the Sunda and Sahul shelves in the early Miocene, the Malesian region has been an important stage on which exchange between Laurasian and Gondwanan floras has played out. The accumulation of dated molecular phylogenies of diverse Malesian lineages now allows deeper exploration of the dynamics of this exchange through time than has hitherto been possible.
We undertook a meta-analysis of published dated phylogenies of plant groups represented in Sunda and Sahul and identified clades that are disjunct across Wallacea (a biogeographical region comprising the Philippines, Sulawesi, Moluccas and Lesser Sunda Islands, which separates the Sunda and Sahul shelves). From these we determined rate and direction of lineage exchange (=migration) through time and related these exchange dynamics to changing landmass configurations, dispersal ecology, and regional lineage diversification. Our results suggest that long distance dispersal was not an important process contributing to the exchange between and assembly of Sunda and Sahul floras, because no disjunctions dated to earlier than c. 20 Ma were. Subsequently, despite the two shelves being in close proximity (<100 km) from c. 18 Ma, exchange was slow until the mid Miocene (c. 12 Ma) when New Guinea orogeny began to intensify. After this time, the exchange rate increased, closely tracking the mean lineage diversification rate across these Malesian plant groups. The successful migrants were predominantly zoochorous, megathermal lineages supporting previous hypotheses of the importance of dispersal mechanism and phylogenetic niche conservatism in the assembly of Sundanian and Sahulian floras.
Why are almost all danthonioid grasses in the Southern Hemisphere?
Hans Peter Linder, University of Zurich
The temperate grass habitat appears to be partitioned into the pooid dominated Northern Hemisphere and the danthonioid dominated Southern Hemisphere. Both subfamilies are cold-adapted C3 grasses, and both have penetrated into the "other" Hemisphere. Whereas the Pooideae contribute substantially to the grass floras of Australasia, they are much less important in southern Africa, and Danthonioideae are rarely dominant in the Northern Hemisphere. Here we document the patterns in this relationship and explore some of the possible reasons. We first ask whether the age of occupation might account for the variation in the importance of the Danthonioideae. A phylogeny-based biogeographical reconstruction suggests an Oligocene origin of danthonioids in southern Africa, with Miocene dispersals to all other southern continents. Pliocene range expansion to the North appears to have occurred in all continents. Species richness in the danthonioids in each area is closely related to the residence time of the clade in that area, consistent with the time-of-occupation hypothesis. Secondly, we ask whether the North might lack suitable climates for danthonioids. Ensemble niche modelling based on a large specimen database showed that all suitable Southern Hemishere areas have danthonioid grasses, but that many apparently suitable Northern Hemisphere regions are devoid of danthonioids, thus inconsistent with the current-climate-control hypothesis. Two further hypotheses have not yet been tested: the competitive-exclusion hypothesis (pooids excluding danthonioids in the North), and the Pleistocene-climate hypothesis (harsher glacial climates excluding danthonioids in the North).
Wilding tree management and research in Australia & spread in New Zealand
Yvonne Buckley, The University of Queensland
Several pine species are considered invasive in Australia including two of the most common plantation species: Pinus radiata and Pinus elliottii (varieties and hybrids with P. caribaea). Invasive pines are most likely to be escapes from existing plantations, and there are approx.. 1 million ha. of plantations in Australia. Australia houses over 18% of the global estate of P. radiata plantations and recent official federal government policy in 1997 was to treble the plantation area in Australia by 2020. While species such as P. radiata, P.elliottii (varieties & hybrids) and P. halapensis are locally recognised as weeds, and naturalized populations occur mostly in woodlands, heathlands and disturbed areas, no pine species is officially listed as a weed in Australia. Little work has been done on the extent and impact of wildings and there is little recognition of the scale and scope of the problem they could potentially present. Here I will discuss the status of pine invasions in Australia and reasons for why they are not perceived as major environmental weeds, I will also discuss their potential to impact on ecosystems of national importance in the future. Pine invasions and research are much better documented in New Zealand. I will briefly present recent work on the spread of P. nigra in New Zealand to illustrate the prediction of spread in complex topography and options for management of spread.
Will climate change cause shifts in abundances of sympatric eucalypt species? Insights from responses to seasonal drought.
Erik Veneklaas, University of Western Australia
Pieter Poot, University of Western Australia
Forests and woodlands in Mediterranean-type climates depend on stored soil moisture during dry summers. In many Southern Hemisphere Mediterranean regions, including southwestern Australia, climate change is causing reduced recharge of soils during winter and increased evapotranspiration during summer, leading to considerable drought stress. We investigated whether differences in water relations may cause shifts in tree vigour and abundance in mixed eucalypt woodlands in southwestern Australia .
At a site where four eucalypt species co-occur, the two species generally inhabiting drier regions (Eucalyptus accedens and E. wandoo) had lower summer leaf water potentials, osmotic potential, and vulnerability to cavitation, and higher stomatal conductance and relative sapflow velocity. Two species typical of less-dry regions (Corymbia calophylla and E. marginata) had remarkably high vulnerabilities to cavitation, and were under greater stress than at nearby sites where these species are dominants. Our results indicate important links between tree water relations and soil physical properties which correlate well with current distribution patterns. Species abundances are likely to change if the drying trend of the climate persists. Recent mortality patterns in two of the four species are consistent with their ecophysiological traits and species distributions.
Will global warming alter mast seeding patterns in tussock grasslands?
Dave Kelly, University of Canterbury
Andre Geldenhuis, University of Canterbury
Alex James, University of Canterbury
E. Penelope Holland, Landcare Research
Michael J Plank, University of Canterbury
William G Lee, Landcare Research and University of Auckland
Philip E Cowan, Landcare Research
Andrea E Byrom, Landcare Research
Many plants worldwide show mast seeding (synchronous highly variable seed crops among years), often triggered by temperature cues. There has been much speculation about how global change might alter the magnitude, frequency, and spacing of high-seed years in mast-seeding species, with downstream effects on seed predation, plant regeneration, and the speed of elevational shifts in species ranges. Whether, and how, climate change alters reproduction depends on the exact mechanisms that plants use to trigger high-seed years. Here we present a novel mechanism for how masting plants respond to temperature cues, using New Zealand snow tussocks (Chionochloa species) as an example. This mechanism fits the observational data better than previous models, and explains why consecutive high-seed years are rarer than consecutive warm years. Crucially, the mechanism predicts that climate-change driven increases in mean temperatures will not cause long-term changes in mast seeding patterns. The new mechanism fits plants from a wide range of plant families and locations in New Zealand and internationally, suggesting that mast seeding is probably more adaptable to changing climates than previously thought.
A 20,000-YEAR-LONG RECORD OF WILDFIRE ACTIVITY FROM FRENCHMANS CAP, TASMANIA, AUSTRALIA
Stahle, Laura N, Department of Earth Sciences, Montana State University
Michael-Shawn Fletcher, Australian National University
Whitlock, Cathy, Montana State University
Simon Haberle, Australian National University
Wildfire has long been recognized as an important feature of the landscape and
vegetation of western Tasmania, Australia, yet there is a dearth of high-resolution records
of local fire activity from this region that span the entire postglacial period. A 20,000-
year high-resolution charcoal record from Lake Vera in southwestern Tasmania
(42°16'28"S, 145°52'42"E) helps reconstruct the postglacial wildfire history of the
Franklin-Gordon Wild Rivers National Park. The site lies within closed rainforest
dominated by Nothofagus cunninghamii and plays host to a number of iconic and firesensitive
tree species, while the broader region is composed of a mosaic of pyrophytic
and pyrophobic vegetation types that has persisted through the Holocene. The late-glacial
period (12,500-17,000 cal yr BP) was characterized by high charcoal levels and highly
variable levels of charcoal as compared with later periods, suggesting extensive fire
activity including some large events. The largest single fire episode of the entire record
occurred at 13,000 cal yr BP. The observed high fire activity corresponds with dry and
steadily warming post-glacial conditions inferred from regional pollen data. Slightly
elevated levels of charcoal in the early Holocene (7500-11,700 cal yr BP) imply
continuation of fire activity during this period. The middle Holocene had relatively few
fire episodes whereas the late Holocene experienced a return of high fire activity and
variability. Discrete and high-magnitude fire episodes occurred between 500-800, 1000-
1400 and 1900-2400 cal yr BP in the late Holocene, suggesting a possible increase in
A high resolution late Glacial / Holocene record from Lake St Clair, Tasmania
Felicitas Hopf, The Australian National University
This poster presents a new, high resolution palaeoenvironmental record from Lake St Clair in western Central Tasmania with a particular focus on the Last Glacial – Interglacial transition (LGIT).
Results to date indicate early deglaciation of the lake before ca 15,090 14C yr BP (18,290 cal. yr BP) at which time high values of alpine grassland and herbfield taxa are replaced by increasing subalpine taxa, most notably Athrotaxis-Diselma type, which come to a pronounced peak around 16,500 cal. yr BP. A renewed increase in Poaceae is of significance at the start of the Antarctic Cold Reversal (ACR) (ca 14,800 cal. yr BP). The end of the ACR is marked by a strong reduction in Phyllocladus aspleniifolius and a switch to Nothofagus cunninghamii as the increasingly dominant rainforest taxon. Peak Nothofagus cunninghamii dominated rainforest development occurs between ca 6,000 and 9,000 cal. yr BP. High charcoal levels occur after 5,350 14C yr BP (6,100 cal. yr BP) and are accompanied by an increase in Eucalyptus spp., Poaceae and Asteraceae. Anodopetalum-Eucryphia type also becomes a more significant component of the rainforest during the late Holocene.
Antarctica helped shape Southern Hemisphere plant distribution patterns
Richard C. Winkworth, Massey University
Françoise Hennion, Université de Rennes 1
Andreas Prinzing, Université de Rennes 1
Marie Hermant, Université des Sciences et Technologies de Lille 1
Steven J. Wagstaff, Landcare Research
Plant fossils suggest Antarctica once supported a diverse flora but that expansion of continental-scale ice sheets triggered the mass extinction these assemblages. The extinction of these Tertiary floras obscures the links between the modern floras of Australia, New Zealand and South America. To evaluate the role of Antarctic in shaping contemporary Southern Hemisphere distribution patterns we examined correlations between divergence time estimates and habitat tolerances for 69 disjunctly distributed austral plant groups. We show that dispersal routes involving Antarctica are required to fully explain the contemporary patterns. We also find that the importance of Antarctic dispersal processes differs with both the geographic context and age of the disjunctions. Our results imply a dynamic dispersal history for Southern Hemisphere plant groups and illustrate how past environmental change has shaped the links between contemporary austral floras. They also provide a novel insight into the impact of future climate change on South Hemisphere plant communities.
Conservation value of Nothofagus forests in Tierra del Fuego: Differences between maps defined by niche factor analysis and Government polices
Guillermo Martínez Pastur, CONICET
Stefan Schindler, University of Vienna
María Vanessa Lencinas, CONICET
Pablo Luis Peri, CONICET
Rosina Soler Esteban, CONICET
Isabel Gamondés Moyano, University of Otago
National legislation in Argentina (26331/07) promotes forest conservation, but biodiversity values are usually not considered in the decision taking, regarding most of the protection to marginal unproductive forests. We develop biodiversity conservation maps using environmental niche factor analysis (software Biomapper 4.0) of understory plants in Nothofagus forests of Tierra del Fuego, and compare the results with conservation strategies promoted by National and Provincial Governments. We used surveys of 535 plots and produced spatially explicit habitat suitability models for 35 vascular plants based on climatic and topographical predictor variables. Further, we produced biodiversity conservation maps (software Arcview 3.0) based on 20 most important plant species (cover + occurrence) for each forest type. Maps showed forests with different conservation value along the landscape. We identified conflicts with timber production and livestock and a deficient conservation strategy of Natural Reserves, because most of them did not included the highest conservation value forests.
Diversity and Origins of Melanesian Leaf-cutter Bees (Megachilidae)
Scott VC Groom, Flinders University
Olivia K Davies, Flinders University
Hien T Ngo, York University
Mark I Stevens, South Australian Museum
Michael P Schwarz, Flinders University
Bees are the primary pollinators in almost all terrestrial ecosystems, and can have major roles in the production of agriculture. Records of bees in the south west pacific (SWP) indicate a very low diversity, with the Fijian bee fauna one of the least diverse, despite an otherwise rich biota. Megachilid bees represent a large proportion of the bee fauna for almost all island groups in the SWP and, because they are wood and stem nesting, their wide distribution is likely to have been influenced by rafting and anthropogenic maritime trade. Our study uses mitochondrial DNA sequence data of megachilid bees from Vanuatu and Fiji to indicate up to twelve and five recent introductions respectively, likely from South East Asia. The study also provides the first records of Heriades in the SWP, and the first record of the subgenus Callomegachile in Fiji. These results indicate that a large proportion of the Melanesian bee fauna is likely to have been introduced only very recently and, therefore, have had only a very recent role in islands ecosystems. This has very wide implications for understanding SWP plant-pollinator relationships. We argue that there is a strong need to understand ancient plant-pollinator relationships that may have evolved in Fiji and Vanuatu prior to the mid-late Pleistocene and Holocene, and whether these could be disrupted by recent bee introductions.
Diversity following volcanic destruction: Palynology of the Early Miocene Foulden Maar, Otago, New Zealand
Dallas C. Mildenhall, GNS Science
Elizabeth M. Kennedy, GNS Science
Daphne E. Lee, University of Otago
Uwe Kaulfuss, University of Otago
Bethany Fox, University of Otago
A pollen and spore record from 26 samples from a 183 m long drill core through biogenic diatomaceous and volcaniclastic sediments of Foulden Maar, Otago gives an unparalleled glimpse into the rich terrestrial biota of Early Miocene New Zealand and provides a detailed history of vegetation change over a very short time period, possibly as little as 100,000 years. Charred palynomorphs at the base of the sedimentary section are related to the volcanic explosion that formed the deep maar crater. At this time a diverse regional podocarp/Casuarina/Brassospora lowland forest flora was present. This was soon replaced by Nothofagus (Brassospora)-dominant regional vegetation with Mallotus/Macaranga dominating the rich, local crater-side vegetation growing on fertile volcanic soils. Pollen from bur reeds, bulrushes, flaxes, jointed rushes and sedges suggest that there were some swampy, shallow water edges to the generally steep-sided crater. It is likely that the vegetation around the margins of the crater was growing on fertile soils derived from nutrient-rich, basaltic tuffs and on infertile soils further away on schist basement. The regional vegetation consisted of forest dominated by Nothofagus, Casuarina, diverse podocarps and araucarians. The local vegetation adjacent to the lake consisted of plants that required abundant water, including Ephedraceae, Asparagaceae, Cyperaceae, Liliaceae, Haloragaceae, Restionaceae and Sparganiaceae. The regional vegetation suggests high, evenly distributed rainfall and warm temperatures. The assemblages belong to the upper Rhoipites waimumuensis/lower Proteacidites isopogiformis palynological zones (latest Oligocene/earliest Miocene, c. 23 Ma), consistent with radiometric, palaeomagnetic and astrochronological data from the core.
Effects of an Australian native parasitic plant on invasive and native hosts
Elizabeth Maciunas, University of Adelaide
Robert Cirocco, University of Adelaide
Associate Professor Jose M Facelli, University of Adelaide
Associate Professor Jennifer R Watling, University of Adelaide
Cassytha pubescens is a common hemiparasitic vine native to south-eastern Australia. It can form dense masses of twining steams on the vegetation, and often the parasite load on individual host plants can be high. In the field, native species present only mild signs under heavy infection. However some invasive species show a substantial reduction in health, and even death, when infected by this parasite. A series of experiment were carried to understand the mechanisms through which the parasite has different effects on native and invasive hosts.
Physiological measurements of parasite and host plants were used to determine their health, as well as assessing the quality of those species as a host for this parasite. The results show that water status and photosynthesis of native species are relatively unaffected by infection, however the effect on all invasive species studied (Scotch broom Cytisus scoparius, European Gorse Ulex europaeus and Blackberry Rubus fructicosus agg.) is severe. These plants show substantial reduction in biomass, particularly root biomass, and an overall decline in health. These results have lead to an interest in this species as a potential biological control agent for these weeds.
Floating kelps in Patagonian Fjords - an important vehicle for rafting invertebrates and its relevance for biogeography
Carla-Sophie Wichmann, Facultad de Ciencias del Mar, Universidad Católica del Norte
Iván A. Hinojosa, Institute for Marine and Antarctic Studies, University of Tasmania
MartinThiel, Centro de Estudios Avanzados en Zonas Áridas (CEAZA)
Floating macroalgae are dispersal vehicles for associated benthic invertebrates. In order to investigate the importance of kelp rafts for species dispersal in the Patagonian Fjord Region (PFR), the abundance and distribution of floating kelps (Macrocystis pyrifera, Durvillaea antarctica) and of the invertebrate fauna associated with M. pyrifera was evaluated during austral spring of 2002-2005, 2008 and 2010. In the southernmost Magellan Region (MR), benthic M. pyrifera were sampled to compare the community structures in both conditions. Floating kelps were abundant in the PFR, harboring a diverse and abundant fauna. The density of floating kelps increased towards the south. In the MR a loss of species was observed between benthic and floating condition (e.g. decapods, echinoderms, peracarids), but a high diversity of organisms from all major phyla were observed on rafts. Throughout the PFR the predominant rafting species belonged to the peracarids, molluscs and annelids, but the community differed between the northern and southern zones of the PFR. Relative abundances of peracarids were higher in northern zones, whereas molluscs and annelids dominated in the southern areas. Species of the peracarid genera Peramphithoe, Gondogeneia, Bircenna and Limnoria were shared between all areas. The results suggest that kelp rafts not only contribute to local population connectivity in the PFR, but could also be an important dispersal vehicle for rafting species along the PFR, crossing the biogeographic boundary around Taitao Peninsula. Furthermore, the MR appears to be an important stepping stone for species dispersal via kelp rafting in the subantarctic region.
Geographic distribution and historical occurrence of Chiasognathus grantii Stephens 1831 (Coleoptera: Lucanidae) in Chile and Argentina.
Olivia E. Vergara, Victoria University of Wellington, NZ
Reinaldo Rivera, University of Concepción, Chile
Cristián E. Hernández, University of Concepción, Chile
Viviane Jerez, University of Concepción, Chile
We analyzed the historical and actual geographical occurrences of Chiasognathus grantii, a stag beetle endemic to the temperate rain forests of Southern Chile and part of Argentina, and an icon for the invertebrate conservation plans in Chile. In the present work we compiled a database of 777 occurrences from fields collected and museum specimens from the years 1890 to 2008, between 36° S and 46° S. This database was integrated into a geographic information system to estimate the potential distribution in a historical and actual biogeographic context. The software MaxEnt was used to generate two potential distributions models in future scenarios (SRES A2: severe scenario and SRES B2: less severe) using future environmental data predictions. The results show that Eco-Regions and precipitation data were the most important variables that influenced the potential distribution models generated. Those models show a discontinuous and aggregated distribution pattern to this species, related mainly with habitats of Nothofagus obliqua (Fagales: Nothofagaceae), N. dombeyi and N. betuloides species. Future models generated by climate change show a decrease in the occurrence probability of this species in a severe scenario. Small and disperse areas with high probability of occurrence (between 40% and 80%) are overlapped with National Parks of the southern “Lagos Region” in Chile. Identification of critical areas through potential distribution modeling may have implications on this species conservation and future biogeographic patterns.
Lake sediments in the Chilean Andes; records of past variability in the Southern Hemisphere Westerlies?
Rixt de Jong, 1) Oeschger Centre for Climate Change Research and Institute of Geography, Bern University, Switzerland
Krystyna Saunders, 1) Oeschger Centre for Climate Change Research and Institute of Geography, Bern University, Switzerland
Alberto Araneda, 2) Centro de CienciasAmbientales, EULA, Universidad de Concepción, Chile
Roberto Urrutia, 2) Centro de CienciasAmbientales, EULA, Universidad de Concepción, Chile
Martin Grosjean, 1) Oeschger Centre for Climate Change Research and Institute of Geography, Bern University, Switzerland
Climate in the central Chilean Andes is characterized by strong seasonal and latitudinal variability. In summer, dry conditions dominate, related to a strong South Pacific Anticyclone. In winter, however, weakening of the anticyclone allows for the northward progression of the westerly wind belt, controlling temperature, wind and precipitation patterns between ca. 32-65 °S. To capture past climatic variability and the position of Westerlies, lake sediments from high-Andean (1500-3000 m a.s.l.) lakes were studied in detail; Laguna Chepical (32.2 S), Laguna El Baul (36.4 S), Laguna la Mula (37.5 S) and Laguna Verde (38.3 S). The geographical position of these lakes, at the northern reaches of the band of Westerlies’ influence, may provide important insight in the behavior of the Westerlies over the past 2000-3000 years.
To reconstruct past winter temperatures, chrysophyte stomatocysts are used. Previous work in European mountain areas has shown that chrysophyte stomatocysts are highly sensitive to cold season (winter to early spring) temperatures. In addition, sediment properties using scanning methods (VIS-RS (visible light range); SPECIM (visible-near infrared light range), magnetic susceptibility) as well as classic methods (total biogenic silica, C/N, organic content) were measured. This study aims to: 1) develop a spatial training set for chrysophyte stomatocysts, 2) test the performance of scanning methods and ‘classic’ methods as a temperature proxy, 3) reconstruct winter temperature variability for the past 1000 yrs and 4) compare reconstructions from all lakes to assess the geographical extent of the Westerly Wind Belt over the past several thousand years.
Landscape scales to evaluate conservation as a component of sustainable forest management: The case of Nothofagus pumilio forests in Tierra del Fuego
María Vanessa Lencinas, CONICET
Guillermo Martínez Pastur, CONICET
Pablo Luis Peri, CONICET
Christopher B. ANDERSON, UNTDF
Rosina Soler Esteban, CONICET
Juan Manuel CELLINI, UNLP
Marcelo BARRERA, UNLP
Isabel Gamondés Moyano, University of Otago
At regional scale, large areas are preserved as natural reserves; at local scale, protection forests are left according to legal restrictions; and at stand scale, variable retention systems are used to improve conservation. This work evaluates the conservation effectiveness at different landscape scales, using Nothofagus pumilio forests (NPF) as a study case. There were used 535 vascular plant surveys (richness and cover) as conservation status indicator in Tierra del Fuego (Argentina), which were analysed using multivariate techniques. At regional scale, NPF plant diversity differed along landscape, where natural reserves are deficient for a regional conservation. At local scale, NPF differed from associated environments, where their preservation does not ensure full conservation. At stand level, aggregates better conserved plant communities than dispersed retention, retaining more structural micro-environmental components of the primary forests. Conservation programs to achieve sustainable NPF management must include different landscape scales, since differences were observed among scales.
Macroinvertebrate diversity in fluvial ecosystems of the Chilean Patagonia: the role of contemporary environmental factors
Anna Astorga, Massey University and University of Oulu
Russell G. Death, Massey University
Josh Markham, Massey University
Timo Muotka, University of Oulu
Marcelo Sanhueza, Centro de Investigación de Ecosistemas de la Patagonia (CIEP)
Pablo Marquet, P.Universidad Católica de Chile & Institute of Ecology and Biodiversity
Patterns of biodiversity can be regulated by both contemporary environmental factors and regional or historical factors. Chilean Patagonia comprises one of the most complex hydrological systems of South America and is an interesting region for examining the different roles that environmental and historical factors have played in regulating diversity patterns. These systems were strongly modified by glacial activity of the Quaternary and more recently, 1930’s and 1940’s, by extensive fires. We studied taxonomic and functional macroinvertebrate diversity in two catchments in the Chilean Patagonia and the main environmental variables related to regional, local and compositional diversity. Macroinvertebrate communities in both catchments were clearly influenced by the west-east precipitation gradient, but also productivity played a key role differentiating the communities of these two neighboring catchments.
Managing an invasive predator pre-adapted to a pulsed resource: A model of stoat (Mustela erminea) irruptions in New Zealand beech forests
C M King, University of Waikato
R A Powell, North Carolina State University
The stoat (Mustela erminea) is a specialist predator that evolved to exploit the unstable populations of northern voles and lemmings. In New Zealand, it is pre-adapted to respond with a population irruption to the resource pulses that follow a heavy seedfall of southern beech (Nothofagus spp.). Culling stoats during an irruption is necessary to reduce damaging predation on nesting endemic birds, but cannot reduce the stoat population long term if the known high natural mortality in peak years exceeds culling mortality. During other phases of the beech-mast cycle, culling might have a greater effect on a smaller stoat population, whether or not damage prevention is critical. We developed a 4-matrix model to predict the effects of culling on λ, the annual rate of change in the size of the stoat population, through the four annual phases of an average masting cycle, explicitly distinguishing between apparent and real culling. In the Post-seedfall phase of the cycle, large numbers of stoats are killed, but little of this extra mortality is additive; in other phases, culling removes larger proportions of smaller total numbers of stoats that would otherwise have lived. Culling throughout all phases is most effective at reducing stoat populations, but is also the most expensive option. Culling has different short-term effects on stoat age distribution depending on the phase of the cycle when culling begins.
Multi-decadal precipitation and westerly wind variability in the mid and high latitudes of the Southern Hemisphere over the last 1000 years
Krystyna M. Saunders, Institute of Geography and Oeschger Centre for Climate Change Research, University of Bern and Institute for Marine and Antarctic Studies
Mark Curran, Australian Antarctic Division and Antarctic Climate & Ecosystems Cooperative Research Centre
Julie Elbert, Institute of Geography and Oeschger Centre for Climate Change Research, University of Bern
Martin Grosjean, Institute of Geography and Oeschger Centre for Climate Change Research, University of Bern
Jennifer Harrison, Australian Nucelar Science & Technology Organisation
Dominic A. Hodgson, British Antarctic Survey
Tessa Vance, Antarctic Climate & Ecosystems Cooperative Research Centre
Tas van Ommen, Australian Antarctic Division and Antarctic Climate & Ecosystems Cooperative Research Centre
The Southern Hemisphere westerly winds are a dominant feature of atmospheric circulation in the mid- to high-latitudes of the Southern Hemisphere. They influence the amount and distribution of precipitation from 40-65°S and play a major role in carbon cycling in the Southern Ocean through their influence on ocean-atmosphere gas exchange. Understanding past westerly wind and precipitation variability is necessary for placing current and predicted changes into context. This study compares multiple wind-inferred and quantitative precipitation reconstructions from the mid- and high-latitudes of the Southern Hemisphere to investigate multi-decadal spatial and temporal variability over the last ca. 1000 years. This presentation outlines initial results and focuses on the wind-based proxy reconstructions from Bathurst Harbour, southern Tasmania (42°S, based on grain size), and Law Dome, East Antarctica (66°S, based on Na+ concentration), and quantitative precipitation reconstructions from Rebecca Lagoon, northwestern Tasmania (41°S), and Lago Plomo, Northern Patagonia (47°S). Potential links to changes in the spatial and temporal influence of the Southern Annular Mode and El Niño Southern Oscillation are highlighted.
Pan trap catches of pollinator insects vary with habitat context
Manu E. Saunders, School of Environmental Sciences, ILWS Charles Sturt University
Gary W. Luck, UNKNOWN
Coloured pan trapping is a simple and efficient method for collecting flying insects, yet there is still discussion over the most effective bowl colour to use for particular target groups (e.g. pollinator insects). The success of particular colours can vary across bioregions and habitat types. Most published pan trap studies have been conducted in the northern hemisphere and very few investigate how habitat context influences pan trap catches. Our study is the first published study to sample pollinator insects in the semi-arid Murray Mallee bioregion of southern Australia using coloured pan traps. It is also one of the first to investigate whether habitat type interacts with trap colour to influence pan trap catches in an Australian environment. We sampled Hymenoptera and Diptera using yellow, white and blue pan traps in native mallee vegetation and two types of managed almond orchards (monoculture and plant-diverse) in northwest Victoria, Australia. Yellow traps caught the most pollinator insects across all habitats, although catches in each coloured trap varied with habitat context. For all pollinator groups combined, blue traps caught more individuals in mallee habitats than in almond orchards. For native hymenopterans, yellow traps caught more individuals in plant-diverse orchards, while blue and white traps had significantly fewer catches in monoculture orchards. Our results highlight the importance of considering the habitat context of individual pan trapping surveys, as no one trap colour is likely to be suitable for trapping pollinator insects across all habitat types.
Phylogenetic studies in Lagenophora Cass. (Lagenophorinae, Asteraceae): A phylogenetic approach to a trans-Pacific genus
Gisela Sancho, División Plantas Vasculares, Museo de La Plata, Paseo del Bosque s.n., La Plata, 1900, Buenos Aires, Argentina
Peter de Lange, Ecosystems and Species Unit, Department of Conservation, Private Bag 68908, Newton 1145, Auckland, New Zealand.
Steven J. Wagstaff, Allan Herbarium, Landcare Research, PO Box 40, Lincoln 7640, New Zealand.
Alternative hypotheses have been postulated to explain the distributional patterns of trans-Pacific flora: vicariant events related to the break-up of Gondwanaland; land bridges that once connected now widely separated continents; or stepping stones for gradual dispersal and long-distance dispersal. How these processes have affected the different trans-Pacific plant groups is in part related to their estimated age of origin. We carried out a global analysis of Lagenophora, including most members of the genus and representatives of closely related genera. Nine species of Lagenophora are distributed throughout mountainous regions of Argentina, Chile and New Zealand. We used independent and combined analyses of ITS, ETS, trnK, and trnL DNA sequences to infer phylogenetic relationships in Lagenophora and its traditionally closely related genera and aimed to explore evolutionary processes such as dispersal, adaptive radiation and extinction that could be responsible for trans-Pacific distributional patterns in the genus. Our preliminary results suggest Lagenophora is not monophyletic; instead they support previous taxonomic treatments that regarded Lagenophora lanata as closely related to Solenogyne. However, the nuclear and chloroplast regions yielded some incongruent resolutions for Lagenophora. The South American species of Lagenophora were not always recovered in a well-supported clade. In some instances the South American clade appears as a derived group nested in the core of Lagenophora. If this placement is maintained in future conclusive analyses, a recent settlement for Lagenophora in South America could be hypothesised.
Pollen Morphology of Some Wilde Acacia species Growing in Saudi Arabia
Ahlam A. Al watban , email@example.com
Ahlam A. Al watban , king saud university saudi arabia
E.A.Al-mogran, king saud university saudi arabia
six species and one subsp. of Acacia belonging to the family mimosaceae were studied for their pollen micromorphological characters such as pollen size, shape, the number of associated monads, colpi and ornamentation of the tectum surface. It was found that the pollen size range from 69.4-42.1µm,,pollen shape was round to semi-round ,the number of associated monads is 16 or 32,the colpy is Y or H shaped and tectum surface orientation among the species was variable. It was foveolate in A. ehrenbergiana, ,; psilate-foveolate in A. nilotica, A. laeta and A. negrii, ; and micro-reticulate in A. farnesiana, A. oerfota, and A. tortilis ssp. raddiana. The studies were carried out under the aid of LM and SEM. The photography was made at various magnifications using JSM-5800 LV( JOEL) Scanning Electron Microscope
Postglacial vegetation, climate and fire history during the last 17,500 years in Valle Chacabuco
Henríquez-González W.I, Instituto de Ecología y Biodiversidad y Departamento de Ciencias Ecológicas, Universidad de Chile
Moreno P.I, Instituto de Ecología y Biodiversidad y Departamento de Ciencias Ecológicas, Universidad de Chile
Villa-Martínez, Centro de estudios del Cuaternario
We present a high resolution pollen and charcoal record from Lago Edita (47°8 ̓S, 72°25 ̓), a small closed-basin lake located in Valle Chacabuco, on the eastern slopes of the Central Patagonian Andes, Chile, to investigate the composition, direction and change chronology of vegetation since the Last Glacial Maximum. The pollen record shows dominance of herbs, shrubs and relatively minor abundance of evergreen rainforest taxa between 17.5 and 14 ka (ka=1000 cal yr B.P.), indicating an open landscape under cold and wet conditions. Fluctuations in the hygrophilous conifer Pilgerodendron, increases of Podocarpus nubigena, Lycopodium, cold-resistant herbs and Pediastrum between 14 and 10.5 ka, suggest more cold and wet climate conditions that the previous interval. This was followed by the establishment of dense Nothofagus forests and declines in hygrophilous and cold-resistant trees (Pilgerodendron, Podocarpus nubigena), herbs and shrubs, suggesting a temperature increase and precipitation decline at the onset of the Holocene. This interval coincided with an increase in macroscopic charcoal accumulation rates suggesting high fire activity. During the last ~9000 years the record shows the continuous dominance of Nothofagus with little variation, suggesting continuous persistence of Nothofagus forests near Lago Edita during this interval. Our results suggest that local of populations of rainforest taxa thrived adjacent to the glacier margins during the last glacial termination and probably during the last glacial maximum along the eastern Andean slopes of Central Patagonia.
Pythons and Biomes: Modelling the effects of Climate Change on the distribution of Australian Pythons.
Matthew Taylor,, School of Earth and Environmental Science, University of Adelaide
Brett A. Goodman, School of Earth and Environmental Science, University of Adelaide
Michael S. Y. Lee, School of Earth and Environmental Science, University of Adelaide
Mark N. Hutchinson, School of Earth and Environmental Science, University of Adelaide
The Australian pythons represent a widespread radiation that has expanded throughout the tropical, arid and parts of the temperate zone biomes of the Australian continent. The current distribution of the group being the result of a combination of colonization by Old World common ancestors (ca. 10 – 35 mya) of the available biomes within the Australian continent, and the subsequent speciation and colonization of more recently formed and unexploited biomes. Despite the distribution of the Australian pythons we know comparatively little about the likely effects that increased aridity and associated climatic change events are likely to have on the current distribution of the Australian pythons. The aim of this research is to use climate layer data from distribution records of each of the known Australian python species and subspecies, and use these data to develop climate envelope models. We will use these data in conjunction with available phylogenetic data for the Australian pythons to examine the direction of the putative evolution of physiological and thermal traits within the group. Finally, we use climate envelop models to highlight those python species most likely to be significantly affected under future predicted climate change scenarios.
Simulating the effects of climate change on the phenology and fructification of Rhodophiala rhodolirion (Baker) Traub. (Amaryllidaceae)
Josefina Cabezas, Universidad de Chile
Paola Jara-Arancio, Universidad de Chile
Mary T K Arroyo, Universidad de Chile
The main effects caused by climate change (CC) in plants are those related to changes in phenology, which may lead, from population disturbances to ecological imbalances. To evaluate these effects, are performed long-term studies, however, there are other methods to simulate the CC, like the OTCs or Open Top Chambers, which increase the heat inside them. In Chile there are no observations of the phenology of the plants over the long term, so in this study was simulated the CC and were monitored several phenological traits, in the native species Rhodophiala rhodolirion, who lives in the central mountain range. The results showed that when de temperature increases in 3.2 °C, there is an advancement of 2.4 days in leaf senescence and 3.2 days in the growth of the stem, which is also accelerated by 0.3 cm/days. The flowering was advanced in five days, floral longevity diminished by 1.2 days, and fruiting decreased by 37.4%. These alterations in the growing season and in the reproductive processes, can lead to a reduced photosynthetic capacity, an asynchrony with pollinators and a decreased in the time available for pollination. This could impair the recruitment, leading, ultimately, to a decrease in population size. This research corresponds to the first steps in Chile that show the potential impacts of the CC on the reproductive process chain, and represents valuable information for the management of the natural heritage.
Southern Westerlies postglacial dynamics at Central Chilean Patagonia (Río Cisnes valley, 44°S)
de Porras Maria Eugenia, Centro de Estudios Avanzados en Zonas Áridas (CEAZA), Raúl Bitran s/n, La Serena, Chile
Maldonado Antonio, Centro de Estudios Avanzados en Zonas Áridas (CEAZA), Raúl Bitran s/n, La Serena, Chile
Quintana Flavia Andrea, CENAC – APN, Fagnano 244, San Carlos de Bariloche, Río Negro, Argentina
Méndez Cesar, Departamento de Antropología, Facultad de Ciencias Sociales, Universidad de Chile, Ignacio Carrera Pinto 1045, Ñuñoa, Santiago, Chile
Reyes Omar, Centro de Estudios del Hombre Austral, Instituto de la Patagonia, Universidad de Magallanes, Avenida Bulnes 01855, Casilla 113-D, Punta Arenas, Chile
Central Chilean Patagonia (44-49°S, South America) is a key area to reconstruct past Southern Westerlies (SW) dynamics through the last glacial-interglacial cycle since its position within their maximal zonal flow and the presence of appropriate terrestrial paleoclimate records. An interdisciplinary project including geomorphology, pollen and fire records since 19kyr BP has been carried out along the Río Cisnes valley (RCv, 44°S) to trace past environmental changes related to SW dynamics. The upper RCv was free of ice by 19kyr BP but the presence of a Late Glacial moraine in the middle RCv points out that the valley was under glacial influence until 13kyr BP. Major vegetation changes were recorded from the Late Glacial to the early Holocene when grass-shrub steppes were replaced by the Nothofagus forest-steppe ecotone in the upper RCv and the deciduous Nothofagus forest in the middle RCv. High fire frequencies associated to the Nothofagus forest development were recorded in RCv around 12.5-8.5kyr BP. A maximum development of the Nothofagus forests along the RCv was recorded during the mid-Holocene whereas high pollen assemblage variability and high fire occurrence characterized the late-Holocene. Climatic changes in RCv were mostly associated to past SW major changes previously recorded along Patagonia from the Late Glacial to the mid-Holocene. During the Late Holocene, a high record variability emerges throughout Central Chilean Patagonia probably related to (1) low magnitude SW changes probably associated to ENSO and/or SAM or (2) the complex relationships between vegetation, fire and human occupations during the last 3kyr.
Subsidies ecosystem as conservation targets
Karina Martínez-Tilleria, Universidad de La Serena, Institute of Ecology and Biodiversity
David López, Universidad de La Serena, Institute of Ecology and Biodiversity
Francisco A. Squeo, Universidad de La Serena, Institute of Ecology and Biodiversity
Carlos F. Gaymer, Universidad de La Serena, Institute of Ecology and Biodiversity
"Ecosystem-based management" involves recognizing interactions at different spatial and temporal scales, within and between ecological and social systems, including stakeholders and managers. This management model is needed in Chile for conservation goals to be effective in the long run. However, even though we are currently working on the adoption of effective legislation and national integration, there are no studies of systematic conservation planning aimed at protecting ecosystem processes as conservation targets. We propose two new conservation targets that seek to protect ecosystem processes between marine-terrestrial ecotones: the coastal fogs and river plumes. The first is a sea-land subsidy known largely responsible for the biodiversity of coastal plant species. The second is a land-sea subsidy, that provides nutrients, oxygen and fresh water, allowing high productivity in the estuaries. For the construction of these conservation targets we used MODIS aqua / terra images. With MARXAN program, we developed a GAP analysis for Chile (including terrestrial and marine environments), using a multi-scale approach, and including the two new conservation targets proposed in this work.
The role of climate and biotic interactions on the Nitrogen cycle in the Atacama Desert
Francisca P. Díaz, Departamento de Ecología, Pontificia Universidad Católica de Chile, Alameda 340, Santiago, Chile. Institute of Ecology and Biodiversity (IEB), Las Palmeras 3425, Ñuñoa, Santiago, Chile.
Claudio Latorre, Departamento de Ecología, Pontificia Universidad Católica de Chile, Alameda 340, Santiago, Chile. Institute of Ecology and Biodiversity (IEB), Las Palmeras 3425, Ñuñoa, Santiago, Chile.
Rodrigo A. Gutiérrez, FONDAP Center for Genome Regulation. Departamento de Genética Molecular y Microbiología. Pontificia Universidad Católica de Chile, Alameda 340, Santiago, Chile.
In the hyperarid Atacama Desert in northern Chile, plants are limited first by climate (precipitation and temperature) and then by nutrients (especially Nitrogen) along with biotic interactions (facilitation and competition). We explore the underlying patterns and interactions between climate, nutrients and biotic interactions. Through the use of soil δ15N, we also trace the impact of these factors on the Nitrogen cycle.
We performed vegetation and soils surveys along a 2000 m altitudinal gradient in the Andes of the Atacama Desert. We characterized the vegetation, nutrient soil data and isotopes (δ15N) from 22 stations located along our survey, from 2500 (MAP <10 mm/yr) to 4500 m (MAP = 160 mm/yr).
Plant species richness and percent relative cover follow a typical “hump-backed” curve with altitude. Total Nitrogen content was low throughout the environmental gradient, but pH and salts were higher at the lower sites whereas ammonium and phosphorus show the same “hump-backed” curve. Mean soil δ15N shows a negative correlation with MAP (R2= 0.75, p < 0.001) as does mean foliar δ15N.
Our results allude to both biotic (plant cover, richness and facilitation) and abiotic (climate gradients) as possible explanations for the soil properties observed. Thus, linear responses were observed for soil pH, salts and δ15N that point to rainfall as the main driver whereas total phosphorus and NH4+ respond in a similar fashion to biotic controls. Hence, the relative roles of climatic forcing versus vegetation dynamics are key aspects for understanding the role of water and nutrient limitation in arid ecosystems.
Trade-Offs between Cattle Production and Bird Conservation in an Agricultural Frontier of the Gran Chaco of Argentina
Matias E Mastrangelo, School of Geography, Enviornment and Earth Sciences, Victoria University of Wellington
Michael C Gavin, School of Geography, Enviornment and Earth Sciences, Victoria University of Wellington
Intensification of food production in the absence of land-use planning can pose a major threat to biological diversity. Decisions on whether to spatially integrate or segregate lands for production and conservation depend in part on the functional relations between biological diversity and agricultural productivity. We measured diversity, density, and species composition of birds along a gradient of production intensification on an agricultural frontier of the Argentine Chaco, where dry forests are cleared for cattle production. Bird species diversity in intact forests was higher than in any type of cattle-production system. Bird species richness decreased nonlinearly as cattle yield increased. Intermediate-intensity silvopastoral systems, in which forest understory is selectively cleared to grow pastures beneath the tree canopy, produced 80% of the mean cattle yield obtained in pastures on cleared areas and were occupied by 70–90% of the number of bird species present in the nearest forest fragments. Densities of >50% of bird species were significantly lower in open pastures than in silvopastoral systems. Therefore, intermediate-intensity silvopastoral systems may have the greatest potential to sustain cattle yield and conserve a large percentage of bird species. However, compared with low-intensity production systems, in which forest structure and extent were intact, intermediate-intensity silvopastoral systems supported significantly fewer forest-restricted bird species and fewer frugivorous birds. These data suggest that the integration of production and conservation through intermediate-intensity silvopastoral systems combined with the protection of forest fragments may be required to maintain cattle yield, bird diversity, and conservation of forest-restricted species in this agricultural frontier.
Using cartography to understand the historical distribution of Araucaria araucana
David Aagesen, State University of New York
Araucaria araucana is a long-lived conifer endemic to the Andes of central Chile and Argentina. Small stands also exist in the Nahuelbuta Mountains near the Chilean coast. The species is a valuable resource to the region's indigenous inhabitants, and in the past it was coveted by the timber industry. Mismanagement of Araucaria araucana has led to its depletion throughout much of its natural range, but changes are difficult to quantify. Historical maps depicting the geographic extent of Araucaria araucana offer some insight into this problem. This poster displays a series of maps of Araucaria araucana’s growth range. The maps were collected during archival and library searches in Chile and Argentina. They span nearly 100 years -- from 1897 to 1992. The maps are useful in understanding the temporal and spatial dynamics of Araucaria araucana, but to make meaningful comparisons it is necessary to understand issues related to data classification, sampling, cartographic accuracy and map scale. On their own, the maps are of limited value. They can be extremely useful, however, when used with field observations and measurements, aerial and landscape photographs, historical text documents, oral histories, ethnohistorical and ethnobotanical information, archaeological evidence, and the palynological and dendrochronological records. This underscores the value of incorporating a multidisciplinary approach when investigating the historical distribution of forest species and ecosystems.
Vegetation and climate changes along the forest-steppe ecotone in central-south Patagonia (47º-51ºS) during and since last glacial termination
Rodrigo Villa-Marínez, Centro de Estudios del Cuaternario (Fundación CEQUA),
Patricio I. Moreno, Instituto de Ecología y Biodiversidad; Departamento de Ciencias Ecológicas, Universidad de Chile
William Henríquez-González, Instituto de Ecología y Biodiversidad; Departamento de Ciencias Ecológicas, Universidad de Chile
Marcela A. Valenzuela , Instituto de Ecología y Biodiversidad; Departamento de Ciencias Ecológicas, Universidad de Chile
We examine forest-steppe ecotone changes between 47-51°S to infer past changes in precipitation delivered by the southern westerly winds (SWW) in central and southern Patagonia. We interpret eastward shifts of this ecotone as indicative of enhanced precipitation, and viceversa. The dominance of herbs (Poaceae) and shrublands in the southern Patagonia sites (51ºS) between 13-11 ka (ka=103 cal yrs BP), suggesting dominance of steppe environments under humid conditions. Pulses of increase of forest occurred between 11-10.5 ka and were followed by a reversal until 7.8 ka indicating decrease of the precipitation. During the last 7.8-7 ka the records are dominated by Nothofagus forest under humid conditions. In central Patagonia (47ºS), pollen records are dominated by Poaceae between 16 and ~9.8 ka, along with hygrophilous cold-resistant conifers and high Andean elements between 13.4-11.6 ka suggest dominance of humid climate conditions. Pollen records show dominance of the forest during the last 9.5 ka. Our results suggest dominance of humid climate conditions during the last glacial termination as result of dominance of the SWW influence in central-south Patagonia. The decrease of precipitation between 11.5 and 9.5-8 ka suggest weaker SWW. This lapse was followed by an increase of precipitation until modern times, which probably was caused by strength of SWW in central-south Patagonia.
Acknowledgments: Fondecyt 1080485, 1121141, ICM P05-002, PFB-23, (*) Becario Conicyt