72 resultados para terrestrial ecosystems

em Deakin Research Online - Australia


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The potential for conservation of individual species has been greatly advanced by the International Union for Conservation of Nature's (IUCN) development of objective, repeatable, and transparent criteria for assessing extinction risk that explicitly separate risk assessment from priority setting. At the IV World Conservation Congress in 2008, the process began to develop and implement comparable global standards for ecosystems. A working group established by the IUCN has begun formulating a system of quantitative categories and criteria, analogous to those used for species, for assigning levels of threat to ecosystems at local, regional, and global levels. A final system will require definitions of ecosystems; quantification of ecosystem status; identification of the stages of degradation and loss of ecosystems; proxy measures of risk (criteria); classification thresholds for these criteria; and standardized methods for performing assessments. The system will need to reflect the degree and rate of change in an ecosystem's extent, composition, structure, and function, and have its conceptual roots in ecological theory and empirical research. On the basis of these requirements and the hypothesis that ecosystem risk is a function of the risk of its component species, we propose a set of four criteria: recent declines in distribution or ecological function, historical total loss in distribution or ecological function, small distribution combined with decline, or very small distribution. Most work has focused on terrestrial ecosystems, but comparable thresholds and criteria for freshwater and marine ecosystems are also needed. These are the first steps in an international consultation process that will lead to a unified proposal to be presented at the next World Conservation Congress in 2012.

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Local adaptation in response to fine-scale spatial heterogeneity is well documented in terrestrial ecosystems. In contrast, in marine environments local adaptation has rarely been documented or rigorously explored. This may reflect real or anticipated effects of genetic homogenization, resulting from widespread dispersal in the sea. However, evolutionary theory predicts that for the many benthic species with complex life histories that include both sexual and asexual phases, each parental habitat patch should become dominated by the fittest and most competitive clones. In this study we used genotypic mapping to show that within headlands, clones of the sea anemone Actinia tenebrosa show restricted distributions to specific habitats despite the potential for more widespread dispersal. On these same shores we used reciprocal transplant experiments that revealed strikingly better performance of clones within their natal rather than foreign habitats as judged by survivorship, asexual fecundity, and growth. These findings highlight the importance of selection for fine-scale environmental adaptation in marine taxa and imply that the genotypic structure of populations reflects extensive periods of interclonal competition and site-specific selection.

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The single most important asset for the conservation of Australia’s unique and globally significant biodiversity is the National Reserve System, a mosaic of over 10,000 discrete protected areas on land on all tenures: government, Indigenous and private,including on-farm covenants, as well as state, territory and Commonwealth marine parks and reserves.THE NATIONAL RESERVE SYSTEMIn this report, we cover major National Reserve System initiatives that have occurred in the period 2002 to the present and highlight issues affecting progress toward agreed national objectives. We define a minimum standard for the National Reserve System to comprehensively, adequately and representatively protect Australia’s ecosystem and species diversity on sea and land. Using government protected area, species and other relevant spatial data, we quantify gaps: those areas needing to move from the current National Reserve System to one which meets this standard. We also provide new estimates of financial investments in protected areas and of the benefits that protected areas secure for society. Protected areas primarily serve to secure Australia’s native plants and animals against extinction, and to promote their recovery.BENEFITSProtected areas also secure ecosystem services that provide economic benefits forhuman communities including water, soil and beneficial species conservation, climatemoderation, social, cultural and health benefits. On land, we estimate these benefitsare worth over $38 billion a year, by applying data collated by the Ecosystem ServicesPartnership. A much larger figure is estimated to have been secured by marineprotected areas in the form of moderation of climate and impact of extreme eventsby reef and mangrove ecosystems. While these estimates have not been verified bystudies specific to Australia, they are indicative of a very large economic contributionof protected areas. Visitors to national parks and nature reserves spend over $23.6 billion a year in Australia, generating tax revenue for state and territory governments of $2.36 billion a year. All these economic benefits taken together greatly exceed the aggregate annual protected area expansion and management spending by all Australian governments, estimated to be ~$1.28 billion a year. It is clear that Australian society is benefiting far greater than its governments’ investment into strategic growth and maintenance of the National Reserve System.Government investment and policy settings play a leading role in strategic growth of the National Reserve System in Australia, and provide a critical stimulus fornon-government investment. Unprecedented expansion of the National Reserve System followed an historic boost in Australian Government funding under Caring for Our Country 2008–2013. This expansion was highly economical for the Australian Government, costing an average of only $44.40 per hectare to buy and protect land forever. State governments have contributed about six times this amount toward the expansion of the National Reserve System, after including in-perpetuity protected area management costs. The growth of Indigenous Protected Areas by the Australian Government has cost ~$26 per hectare on average, including management costs capitalised in-perpetuity, while also delivering Indigenous social and economic outcomes. The aggregate annual investment by all Australian governments has been ~$72.6 million per year on protected area growth and ~$1.21 billion per year on recurrent management costs. For the first time in almost two decades, however, the Australian Government’s National Reserve System Program, comprising a specialist administrative unit and funding allocation, was terminated in late 2012. This program was fundamental in driving significant strategic growth in Australia’s protected area estate. It is highly unlikely that Australia can achieve its long-standing commitments to an ecologically representative National Reserve System, and prevent major biodiversity loss, without this dedicated funding pool. The Australian Government has budgeted ~$400 million per year over the next five years (2013-2018) under the National Landcare and related programs. This funding program should give high priority to delivery of national protected area commitments by providing a distinct National Reserve System funding allocation. Under the Convention on Biological Diversity (CBD), Australia has committed to bringing at least 17 percent of terrestrial and at least 10 per cent of marine areas into ecologically representative, well-connected systems of protected areas by 2020 (Aichi Target 11).BIODIVERSITY CONSERVATIONAustralia also has an agreed intergovernmental Strategy for developing a comprehensive, adequate and representative National Reserve System on land andsea that, if implemented, would deliver on this CBD target. Due to dramatic recent growth, the National Reserve System covers 16.5 per cent of Australia’s land area, with highly protected areas, such as national parks, covering 8.3 per cent. The marine National Reserve System extends over one-third of Australian waters with highly protected areas such as marine national parks, no-take or green zones covering 13.5 per cent. Growth has been uneven however, and the National Reserve System is still far from meeting Aichi Target 11, which requires that it also be ecologically representative and well-connected. On land, 1,655 of 5,815 ecosystems and habitats for 138 of 1,613 threatened species remain unprotected. Nonetheless, 436 terrestrial ecosystems and 176 threatened terrestrial species attained minimum standards of protection due to growth of the National Reserve System on land between 2002 and 2012. The gap for ecosystem protection on land – the area needed to bring all ecosystems to the minimum standard of protection – closed by a very substantial 20 million hectares (from 77 down to 57 million hectares) between 2002 and 2012, not including threatened species protection gaps. Threatened species attaining a minimum standard for habitat protection increased from 27 per cent to 38 per cent over the decade 2002–2012. A low proportion of critically endangered species meeting the standard (29 per cent) and the high proportion with no protection at all (20 per cent) are cause for concern, but one which should be relatively easy to amend, as the distributions of these species tend to be small and localised. Protected area connectivity has increased modestly for terrestrial protected areas in terms of the median distance between neighbouring protected areas, but this progress has been undermined by increasing land use intensity in landscapes between protected areas.A comprehensive, adequate and representative marine reserve system, which meetsa standard of 15 per cent of each of 2,420 marine ecosystems and 30 per cent of thehabitats of each of 177 marine species of national environmental significance, wouldrequire expansion of marine national parks, no-take or green zones up to nearly 30per cent of state and Australian waters, not substantially different in overall extentfrom that of the current marine reserve system, but different in configuration.Protection of climate change refugia, connectivity and special places for biodiversityis still low and requires high priority attention. FINANCING TO FILL GAPS AND MEET COMMITMENTSIf the ‘comprehensiveness’ and ‘representativeness’ targets in the agreed terrestrial National Reserve System Strategy were met by 2020, Australia would be likely to have met the ‘ecologically representative’ requirement of Aichi Target 11. This would requireexpanding the terrestrial reserve system by at least 25 million hectares. Considering that the terrestrial ecosystem protection gap has closed by 20 million hectares over the past decade, this required expansion would be feasible with a major boost in investment and focus on long-standing priorities. A realistic mix of purchases, Indigenous Protected Areas and private land covenants would require an Australian Government National Reserve System investment of ~$170 million per year over the five years to 2020, representing ~42 per cent of the $400 million per year which the Australian Government has budgeted for landcare and conservation over the next five years. State, territory and local governments, private and Indigenous partners wouldlikewise need to boost financial commitments to both expand and maintain newprotected areas to meet the agreed National Reserve System strategic objectives.The total cost of Australia achieving a comprehensive, adequate and representativemarine reserve system that would satisfy Aichi Target 11 is an estimated $247 million.

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Species composition is expected to alter ecological function in assemblages if species traits differ strongly. Such effects are often large and persistent for nonnative carnivores invading islands. Alternatively, high similarity in traits within assemblages creates a degree of functional redundancy in ecosystems. Here we tested whether species turnover results in functional ecological equivalence or complementarity, and whether invasive carnivores on islands significantly alter such ecological function. The model system consisted of vertebrate scavengers (dominated by raptors) foraging on animal carcasses on ocean beaches on two Australian islands, one with and one without invasive red foxes (Vulpes vulpes). Partitioning of scavenging events among species, carcass removal rates, and detection speeds were quantified using camera traps baited with fish carcasses at the dune–beach interface. Complete segregation of temporal foraging niches between mammals (nocturnal) and birds (diurnal) reflects complementarity in carrion utilization. Conversely, functional redundancy exists within the bird guild where several species of raptors dominate carrion removal in a broadly similar way. As predicted, effects of red foxes were large. They substantially changed the nature and rate of the scavenging process in the system: (1) foxes consumed over half (55%) of all carrion available at night, compared with negligible mammalian foraging at night on the fox-free island, and (2) significant shifts in the composition of the scavenger assemblages consuming beach-cast carrion are the consequence of fox invasion at one island. Arguably, in the absence of other mammalian apex predators, the addition of red foxes creates a new dimension of functional complementarity in beach food webs. However, this functional complementarity added by foxes is neither benign nor neutral, as marine carrion subsidies to coastal red fox populations are likely to facilitate their persistence as exotic carnivores.

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Coarse woody debris (CWD) is a common structural component of terrestrial ecosystems, and provides important habitat for biota. Fires modify the distribution of CWD, both spatially and temporally. Changes in fire regimes, such as those arising from prescribed burning and changing climatic conditions, make it critical to understand the response of this resource to fire. We created a conceptual model of the effects of fire on logs and dead trees in topographically diverse forests in which trees often survive severe fire. We then surveyed paired sites, in a damp gully and adjacent drier slope, ~3.5. years after a large wildfire in south-eastern Australia. Sites were stratified by fire severity (unburnt, understorey burnt and severely burnt), and fire history (burnt ≤3. years or ≥20. years prior to the wildfire). Both components of the fire regime influenced CWD availability in gullies. Severe wildfire and fire history ≤3. years reduced the volume of small logs (10-30. cm diameter) in gullies, while severe wildfire increased the number of large dead trees in gullies. CWD on slopes was not affected by fire severity or history at ~3.5. years post-fire. Log volumes on slopes may recover more quickly after wildfire through rapid collapse of branches and trees. Gullies generally supported more logs than slopes, but longer inter-fire intervals in gullies may allow fuel loads to accumulate and lead to comparatively larger fire impacts. Given that fire severity and fire interval are predicted to change in many fire-prone ecosystems in coming decades, this study highlights the importance of understanding the interacting effects of multiple components of the fire regime with landscape structure. In particular, variation in fire interval and fire severity in relation to topographic position will influence the pattern of accumulation of coarse woody debris across the landscape, and therefore the structure and quality of habitats for biota.

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Apex predators perform important functions that regulate ecosystems worldwide. However, little is known about how ecosystem regulation by predators is influenced by human activities. In particular, how important are top-down effects of predators relative to direct and indirect human-mediated bottom-up and top-down processes? Combining data on species' occurrence from camera traps and hunting records, we aimed to quantify the relative effects of top-down and bottom-up processes in shaping predator and prey distributions in a human-dominated landscape in Transylvania, Romania. By global standards this system is diverse, including apex predators (brown bear and wolf), mesopredators (red fox) and large herbivores (roe and red deer). Humans and free-ranging dogs represent additional predators in the system. Using structural equation modelling, we found that apex predators suppress lower trophic levels, especially herbivores. However, direct and indirect top-down effects of humans affected the ecosystem more strongly, influencing species at all trophic levels. Our study highlights the need to explicitly embed humans and their influences within trophic cascade theory. This will greatly expand our understanding of species interactions in human-modified landscapes, which compose the majority of the Earth's terrestrial surface.

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Aim: Globally, urbanization is one of the most widespread, intense and ecologically destructive forms of landscape transformation, and it is often concentrated in coastal areas. Theoretically, species losses attributable to urbanization are predicted not to alter overall ecosystem function if functional redundancy (i.e. replacement of function by alternative species) compensates for such losses. Here, we test this expectation by measuring how coastal urbanization affects scavenger guilds on sandy beaches and whether changes in guild composition result either in an overall loss of scavenging efficiency, or in functional compensation under alternative guild structures, maintaining net ecosystem functioning. Location: Fourteen beaches along the east coast of Australia with variable levels of urbanization. Methods: Scavenging communities and rates of carrion removal were determined using motion-triggered cameras at the beach-dune interface. Results: A substantial shift in the community structure of vertebrate scavengers was associated with gradients in urbanization. Iconic and functionally important raptors declined precipitously in abundance on urban beaches. Importantly, other vertebrates usually associated with urban settings (e.g. dogs, foxes, corvids) did not functionally replace raptors. In areas where < 15% of the abutting land had been developed into urban areas, carcass removal by scavengers was often complete, but always > 70%. Conversely, on beaches bordering coastal cities with < 40% of natural vegetation remaining, two-thirds of fish carcasses remained uneaten by scavengers. Raptors removed 70-100% of all deployed fish carcasses from beaches with < 8% urban land cover, but this number dropped significantly with greater levels of urbanization and was not compensated by other scavenger species in urban settings. Main conclusions: There is limited functional redundancy in vertebrate scavenger communities of sandy beach ecosystems, which impacts the system's capacity to mitigate the ecological consequences of detrimental landscape transformations.

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 An understanding of risks to biodiversity is needed for planning action to slow current rates of decline and secure ecosystem services for future human use. Although the IUCN Red List criteria provide an effective assessment protocol for species, a standard global assessment of risks to higher levels of biodiversity is currently limited. In 2008, IUCN initiated development of risk assessment criteria to support a global Red List of ecosystems. We present a new conceptual model for ecosystem risk assessment founded on a synthesis of relevant ecological theories. To support the model, we review key elements of ecosystem definition and introduce the concept of ecosystem collapse, an analogue of species extinction. The model identifies four distributional and functional symptoms of ecosystem risk as a basis for assessment criteria: a) rates of decline in ecosystem distribution; b) restricted distributions with continuing declines or threats; c) rates of environmental (abiotic) degradation; and d) rates of disruption to biotic processes. A fifth criterion, e) quantitative estimates of the risk of ecosystem collapse, enables integrated assessment of multiple processes and provides a conceptual anchor for the other criteria. We present the theoretical rationale for the construction and interpretation of each criterion. The assessment protocol and threat categories mirror those of the IUCN Red List of species. A trial of the protocol on terrestrial, subterranean, freshwater and marine ecosystems from around the world shows that its concepts are workable and its outcomes are robust, that required data are available, and that results are consistent with assessments carried out by local experts and authorities. The new protocol provides a consistent, practical and theoretically grounded framework for establishing a systematic Red List of the world’s ecosystems. This will complement the Red List of species and strengthen global capacity to report on and monitor the status of biodiversity.

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We begin by briefly examining the achievements of the IUCN Red List of Threatened Species, and offering it as the model and motivator for the creation of the IUCN Red List of Ecosystems (RLE). The history of the RLE concept within IUCN is briefly summarized, from the first attempt to formally establish an RLE in 1996 to the present. Major activities since 2008, when the World Conservation Congress initiated a "consultation process for the development, implementation and monitoring of a global standard for the assessment of ecosystem status, applicable at local, regional and global levels," have included: Development of a research agenda for strengthening the scientific foundations of the RLE, publication of preliminary categories and criteria for examination by the scientific and conservation community, dissemination of the effort widely by presenting it at workshops and conferences around the world, and encouraging tests of the system for a diversity of ecosystem types and in a variety of institutional settings. Between 2009 and 2012, the Red List of Ecosystems Thematic Group of the IUCN Commission on Ecosystem Management organized 18 workshops and delivered 17 conferences in 20 countries on 5 continents, directly reaching hundreds of participants. Our vision for the future includes the integration of the RLE to the other three key IUCN knowledge products (IUCN Red List of Threatened Species, World Database on Protected Areas and Key Biodiversity Areas), in an on-line, user-driven, freely-accessible information management system for performing biodiversity assessments. In addition we wish to pilot the integration of the RLE into land/water use planning and macro-economic planning. Fundamental challenges for the future include: Substantial expansion in existing institutional and technical capacity (especially in biodiversity-rich countries in the developing world), progressive assessment of the status of all terrestrial, freshwater, marine and subterranean ecosystems, and development of a map of the ecosystems of the world. Our ultimate goal is that national, regional and global RLEs are used to inform conservation and land/water use decision-making by all sectors of society. © Author(s) 2012.

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The newly developed IUCN Red List of Ecosystems is part of a growing toolbox for assessing risks to biodiversity, which addresses ecosystems and their functioning. The Red List of Ecosystems standard allows systematic assessment of all freshwater, marine, terrestrial and subterranean ecosystem types in terms of their global risk of collapse. In addition, the Red List of Ecosystems categories and criteria provide a technical base for assessments of ecosystem status at the regional, national, or subnational level. While the Red List of Ecosystems criteria were designed to be widely applicable by scientists and practitioners, guidelines are needed to ensure they are implemented in a standardized manner to reduce epistemic uncertainties and allow robust comparisons among ecosystems and over time. We review the intended application of the Red List of Ecosystems assessment process, summarize 'best-practice' methods for ecosystem assessments and outline approaches to ensure operational rigour of assessments. The Red List of Ecosystems will inform priority setting for ecosystem types worldwide, and strengthen capacity to report on progress towards the Aichi Targets of the Convention on Biological Diversity. When integrated with other IUCN knowledge products, such as the World Database of Protected Areas/Protected Planet, Key Biodiversity Areas and the IUCN Red List of Threatened Species, the Red List of Ecosystems will contribute to providing the most complete global measure of the status of biodiversity yet achieved.

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The emerging field of blue carbon science is seeking cost-effective ways to estimate the organic carbon content of soils that are bound by coastal vegetated ecosystems. Organic carbon (Corg) content in terrestrial soils and marine sediments has been correlated with mud content (i.e. silt and clay), however, empirical tests of this theory are lacking for coastal vegetated ecosystems. Here, we compiled data (n = 1345) on the relationship between Corg and mud (i.e. silt and clay, particle sizes <63 μm) contents in seagrass ecosystems (79 cores) and adjacent bare sediments (21 cores) to address whether mud can be used to predict soil Corg content. We also combined these data with the δ13C signatures of the soil Corg to understand the sources of Corg stores. The results showed that mud is positively correlated with soil Corg content only when the contribution of seagrass-derived Corg to the sedimentary Corg pool is relatively low, such as in small and fast growing meadows of the genera Zostera, Halodule and Halophila, and in bare sediments adjacent to seagrass ecosystems. In large and long-living seagrass meadows of the genera Posidonia and Amphibolis there was a lack of, or poor relationship between mud and soil Corg content, related to a higher contribution of seagrass-derived Corg to the sedimentary Corg pool in these meadows. The relative high soil Corg contents with relatively low mud contents (i.e. mud-Corg saturation) together with significant allochthonous inputs of terrestrial organic matter could overall disrupt the correlation expected between soil Corg and mud contents. This study shows that mud (i.e. silt and clay content) is not a universal proxy for blue carbon content in seagrass ecosystems, and therefore should not be applied generally across all seagrass habitats. Mud content can only be used as a proxy to estimate soil Corg content for scaling up purposes when opportunistic and/or low biomass seagrass species (i.e. Zostera, Halodule and Halophila) are present (explaining 34 to 91% of variability), and in bare sediments (explaining 78% of the variability).

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Carbon cycling on the east coast of Australia has the potential to be strongly affected by El Niño-Southern Oscillation (ENSO) intensification and coastal development (industrialization and urbanization). We performed paleoreconstructions of estuarine sediments from a seagrass-dominated estuary on the east coast of Australia (Tuggerah Lake, New South Wales) to test the hypothesis that millennial-scale ENSO intensification and European settlement in Australia have increased the transfer of organic carbon from land into coastal waters. Our data show that carbon accumulation rates within coastal sediments increased significantly during periods of maximum millennial-scale ENSO intensity ("super-ENSO") and coastal development. We suggest that ENSO and coastal development destabilize and liberate terrestrial soil carbon, which, during rainfall events (e.g., La Niña), washes into estuaries and becomes trapped and buried by coastal vegetation (seagrass in this case). Indeed, periods of high carbon burial were generally characterized as having rapid sedimentation rates, higher content of fine-grained sediments, and increased content of wood and charcoal fragments. These results, though preliminary, suggest that coastal development and ENSO intensificationboth of which are predicted to increase over the coming centurycan enhance capture and burial of terrestrial carbon by coastal ecosystems. These findings have important relevance for current efforts to build an understanding of terrestrial- marine carbon connectivity into global carbon budgets.

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■ Human well-being has several key components: the basic material needs for a good life, freedom and choice, health, good social relations, and personal security. Well-being exists on a continuum with poverty, which has been defined as"pronounced deprivation in well-being."
■ How well-being and ill-being, or poverty, are expressed and experienced is context- and situation-dependent, reflecting local social and personal factors such as geography, ecology, age, gender,and culture.These concepts are complex and value-laden.
Ecosystems are essential for human well-being through their provisioning, regulating, cultural, and supporting services. Evidence in recent decades of escalating human impacts. on ecological systems worldwide raises concerns about the consequences of ecosystem changes for human well-being.
■ Human well-being can be enhanced through sustainable human interaction with ecosystems with the support of appropriate instruments, institutions, organizations, and technology. creation of these through participation and transparency may contribute to people's freedoms and choices and to increased economic, social,and ecological security.
■ Some believe that the problems from the depletion and degradation of ecological capital can be largely overcome by the substitution of physical and human capital. Others believe that there are more significant limits to such substitutions.The scope for substitutions varies by socioeconomic status.
■ We identify direct and indirect pathways between ecosystem change and human well-being,whether it be positive or negative.lndirect effects are characterized by more complex webs of causation, involving social, economic, and political threads. Threshold points exist beyond which rapid changes to human well-being can occur.
■ Indigent poorly resourced, and otherwise disadvantaged communities are generally the most vulnerable to adverse ecosystem change. Spirals, both positive and negative, can occur for any population, but the poor are more vulnerable.      
■ Functioning institutions are vital to enable equitable access to ecosystem services. lnstitutions sometimes fail or remain undeveloped because of powerful individuals or groups. Bodies that mediate the distribution of goods and services may also be appropriated for the benefit of powerful minorities.
■ For poor people, the greatest gains in well-being will occur through more equitable and secure access to ecosystem services. In the long run, the rich can contribute greatly to human well-being by reducing their substantial impacts on ecosystems and by facilitating greater access to ecosystem services by the poor.
■ We argue ecological security warrants recognition as a sixth freedom of equal weight with participative freedom, economic   facilities, social opportunities, transparency guarantees, and protective security.

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The rate and spatial scale at which natural environments are being modified by human land-uses mean that a regional or national perspective is necessary to understand the status of the native biota. Here, we outline a landscape-based approach for using data from the ‘New Atlas of Australian Birds’ to examine the distribution and status of avifauna at a regional scale. We use data from two bioregions in south-east Australia – the Gippsland Plain and the Strzelecki Ranges (collectively termed the greater Gippsland Plains) – to demonstrate this approach. Records were compiled for 57 landscape units, each 10′ latitude by 10′ longitude (~270 km2) across the study region. A total of 165 terrestrial bird species was recorded from 1870 ‘area searches’, with a further 24 species added from incidental observations and other surveys. Of these, 108 species were considered ‘typical’ of the greater Gippsland Plain in that they currently or historically occur regularly in the study region. An index of species ‘occurrence’, combining reporting rate and breadth of distribution, was used to identify rare, common, widespread and restricted species. Ordination of the dataset highlighted assemblages of birds that had similar spatial distributions. A complementarity analysis identified a subset of 14 landscape units that together contained records from at least three different landscape units for each of the 108 ‘typical’ species. When compared with the 40 most common ‘typical’ species, the 40 least common species were more likely to be forest specialists, nest on the ground and, owing to the prevalence of raptors in the least common group, take prey on the wing. The future status of the terrestrial avifauna of the greater Gippsland Plains will depend on the extent to which effective restoration actions can be undertaken to ensure adequate representation of habitats for all species, especially for the large number of species of conservation concern.

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The adjoining area of western Guizhou and eastern Yunnan Provinces in southwest China is an ideal place to investigate the feasibility of correlating marine and nonmarine Permian–Triassic boundary (PTB) sequences, as it contains outcrop sections of shallow marine, marginal marine (or paralic), and terrestrial PTB sections, all in close geographic proximity. This paper documents for the first time multiple stratigraphic data from several well-preserved terrestrial PTB sections in the area and attempts to use these data to define, locate, and correlate the PTB in the area. A study of the spores and pollen and vegetation types across the terrestrial PTB sections in the study area suggests three distinct evolutionary stages across the boundary: Stage 1 (Xuanwei Formation) is characterised by Late Permian or Paleozoic-type ferns and pteridosperms (85.0%), with a few gymnosperms (15.0%); stage 2 is marked by an abrupt drop of sporopollen elements of Late Permian aspects, coupled with the appearance of fungal spores and limited Early Triassic palynomorphs; stage 3 (top Xuanwei Formation and Kayitou Formation) is dominated by gymnosperm pollen (58.8%) of clearly Early Triassic aspect, although still retaining limited ferns and pteridosperms. The three biotic stages seem to well correspond with the changing trend of the δ13Corg curves from the same sections, which is characterized by a sharp drop just before the PTB, followed by a short term partial recovery across the boundary, and then succeeded by a gradual decline after the PTB in the Early Triassic. Combining evidence from eventostratigraphic (i.e., the succession of boundary clay beds), biostratigraphic (using both macroplants and palynomorphs), and chemostratigraphic (i.e., organic carbon isotope excursion signals), we propose that a high-resolution PTB succession, closely correlatable to its marine counterpart at the Meishan section in eastern China, is recognisable at the terrestrial PTB sections in the western Guizhou–eastern Yunnan area in southwest China.