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Fire regimes are shifting under climate change. Decadal-scale shifts in fire regime can disrupt the biogeochemical cycling of carbon (C), nitrogen (N), and phosphorus (P) within forest ecosystems, but the full extent of these disruptions is unknown. It is also unclear whether these disruptions have consequences for the ecological characteristics (e.g., biomass, abundance, and composition) of microbial and invertebrate communities, which together comprise the majority of terrestrial biodiversity and underpin many ecosystem processes. The theoretical framework of ecological stoichiometry has great potential in this context, but it has rarely been used to develop an integrated understanding of the biogeochemical and ecological effects of altered fire regime across trophic levels. Using one of the world’s longest-running fire experiments, located in Queensland, Australia, we carried out a comprehensive investigation into the stoichiometric consequences of a decadal-scale divergence in prescribed fire frequency and their links to coinciding changes in various structural characteristics of forest floor microbial and invertebrate communities. Forty-three years of biennial burning led to significantly N-depleted and/or P-enriched stoichiometry in soil, leaf litter, leaf litter-associated microbial biomass, and certain groups of invertebrates (significant effect sizes ranging 27–36%), although total invertebrate community stoichiometry was unaffected. Microbial biomass was 42% lower in biennially burned soils. Invertebrate community composition differed between fire regime treatments on some sampling dates, but fire regime did not have consistent effects on invertebrate biomass of abundance. Microbial biomass and the abundances of some invertebrate taxa were depressed at particularly low and/or high resource N:P, consistent with a coupling of these variables to the stoichiometric effects of decadal-scale fire regime. Litter transplants likewise indicated that some invertebrate abundances were sensitive to litter properties over twelve months. Together, our results indicate that long-term changes in fire regime can decouple the within-ecosystem cycling of N and P, with N and P cycling growing more and less conservative, respectively, under high-frequency fire in a way that propagates throughout forest floor food webs. Our study provides new insights into the coupled biogeochemical and ecological responses of forest ecosystems to novel fire regimes and establishes a basis for a stoichiometric framework for fire ecology.

Globally, baleen whales were severely depleted by historic whaling. Recovering populations have been observed to alter their behaviour. These changes have been attributed to climate change in some cases and raise concerns over the successful recovery of baleen whale populations. Current data‐driven statistical habitat and behavioural models have proven useful for addressing questions of whale distribution changes within their limitations. Given observed changes in oceanic conditions, a new approach to managing baleen whale population recovery is necessary. Model predictions of future whale movements and distributions under climate change scenarios are vital to enable adequate conservation management. This paper presents a new perspective on understanding the impacts of climate change on humpback whales, arguing the need for a system‐based multidisciplinary research approach. Our approach includes coupled, mechanistic models based upon robust ecological principles, and integrates key physical, biogeochemical, biological and ecological modules to address long‐term changes associated with climate change. To illustrate the need for this system‐based multidisciplinary approach, we focus on Southern Hemisphere humpback whales, the recovery of which may be impacted by rapid changes in habitat conditions brought about by anthropogenic climate change.

New evidence of impacts by feral horses in Australia's alpine parks systems confirms they endanger threatened species and extensively damage critically endangered bog communities that could take millennia to recover. These impacts are not confounded by effects of deer and accumulate over time, even when only a small number of feral horses (~100) are present. With protected areas representing only a small proportion of the area of the Australian states of New South Wales (9.3%) and Victoria (17%), allowing feral horses to degrade reserves is not a reasonable management compromise, is contrary to the purpose of the protected area system and conflicts with international obligations. Modelling and decades of management experience indicate that trapping alone does not control feral horse numbers. Trapping and fertility control can work in small populations, but not when there are several thousand horses in remote areas. Aerial culling is needed to cost-effectively and humanely control feral horse populations. The relatively small amount of suffering feral horses experience during a cull is outweighed by (i) avoiding suffering and death of horses from starvation and thirst, (ii) avoiding the suffering of native animals displaced by horses and (iii) avoiding the ethical concerns of driving threatened species towards extinction. Objections to aerial culling on welfare and cultural grounds are contradicted by evidence. Improving knowledge in the general community about what is at stake is long overdue because without this knowledge, small groups with vested interests and unfounded claims have been able to dominate debate and dictate management actions. As a result of ineffective management, horse populations are now expanding and causing well-documented damage to Australia's alpine parks, placing at risk almost $10M spent on restoration after livestock grazing ended. The costs of horse control and restoration escalate the longer large horse populations remain in the alpine parks. It is crucial that feral horse numbers are rapidly reduced to levels where ecosystems begin to recover. Aerial culling is needed as part of the toolbox to achieve that reduction.

The biogeochemical and stoichiometric signature of vegetation fire may influence post-fire ecosystem characteristics and the evolution of plant 'fire traits'. Phosphorus (P), a potentially limiting nutrient in many fire-prone environments, might be particularly important in this context; however, the effects of fire on P cycling often vary widely. We conducted a global-scale meta-analysis using data from 174 soil studies and 39 litter studies, and found that fire led to significantly higher concentrations of soil mineral P as well as significantly lower soil and litter carbon:P and nitrogen:P ratios. These results demonstrate that fire has a P-rich signature in the soil-plant system that varies with vegetation type. Further, they suggest that burning can ease P limitation and decouple the biogeochemical cycling of P, carbon and nitrogen. These effects resemble a transient reversion to an earlier stage of ecosystem development, and likely underpin at least some of fire's impacts on ecosystems and organisms. © 2018 John Wiley & Sons Ltd/CNRS.

Wilderness areas are ecologically intact landscapes predominantly free of human uses, especially industrial-scale activities that result in substantial biophysical disturbance. This definition does not exclude land and resource use by local communities who depend on such areas for subsistence and bio-cultural connections. Wilderness areas are important for biodiversity conservation and sustain key ecological processes and ecosystem services that underpin planetary life-support systems. Despite these widely recognized benefits and values of wilderness, they are insufficiently protected and are consequently being rapidly eroded. There are increasing calls for multilateral environmental agreements to make a greater and more systematic contribution to wilderness conservation before it is too late. We created a global map of remaining terrestrial wilderness following the established last-of-the-wild method, which identifies the 10% of areas with the lowest human pressure within each of Earth's 62 biogeographic realms and identifies the 10 largest contiguous areas and all contiguous areas >10,000 km2 . We used our map to assess wilderness coverage by the World Heritage Convention and to identify gaps in coverage. We then identified large nationally designated protected areas with good wilderness coverage within these gaps. One-quarter of natural and mixed (i.e., sites of both natural and cultural value) World Heritage Sites (WHS) contained wilderness (total of 545,307 km2 ), which is approximately 1.8% of the world's wilderness extent. Many WHS had excellent wilderness coverage, for example, the Okavango Delta in Botswana (11,914 km2 ) and the Central Suriname Nature Reserve (16,029 km2 ). However, 22 (35%) of the world's terrestrial biorealms had no wilderness representation within WHS. We identified 840 protected areas of >500 km2 that were predominantly wilderness (>50% of their area) and represented 18 of the 22 missing biorealms. These areas offer a starting point for assessing the potential for the designation of new WHSs that could help increase wilderness representation on the World Heritage list. We urge the World Heritage Convention to ensure that the ecological integrity and outstanding universal value of existing WHS with wilderness values are preserved.

Economic growth is often in conflict with environmental goals. Biodiversity offsetting attempts to resolve this conflict by requiring industries to compensate for the biodiversity loss they cause, by generating an equivalent biodiversity gain elsewhere. Offsets for environmental impacts are increasingly being seen as a way to help meet preexisting conservation targets, such as those relating to the establishment and management of protected areas. We examine how using offsets to meet a state or organization's genuine commitments, which are not contingent on the offsets, results in no additional conservation benefit. In this case, either the offset or the preexisting commitment is invalid. For example, the use of offsets to meet commitments under the Convention on Biological Diversity requires an admission that those commitments would otherwise not be met. This interaction between international agreements around protected areas and offset policy can generate perverse incentives, which must be carefully managed to avoid poor conservation outcomes. We propose separate accounting for conservation gains generated using offsets, and that future conservation agreements and targets should explicitly separate commitments met using offset gains from those which are not reliant on equivalent losses.

The World Heritage Convention could make a bigger and more systematic contribution to global wilderness conservation by: (1) ensuring the World Heritage List includes full coverage of Earth's wilderness areas with outstanding universal value and (2) more effectively protecting the ecological integrity of existing World Heritage sites. Here, we assess current coverage of global-scale wilderness areas within natural World Heritage sites and identify broad gaps where new wilderness sites should be identified for inclusion in the World Heritage List. We also consider how existing mechanisms under the Convention can improve the ecological integrity of existing sites by expanding or buffering them, and by promoting connectivity between World Heritage sites, between World Heritage sites and other protected areas, or both. We suggest that the Convention should consider a new mechanism called a “World Heritage Wilderness Complex” to facilitate a wilderness approach. Finally, we map three landscapes and one seascape to illustrate how World Heritage Wilderness Complexes might be implemented.

The effectiveness of revegetation in providing habitat for fauna is expected to be determined both by within-site factors and attributes of the landscape in which a revegetation site occurs. Most studies of fauna in revegetation have been conducted in landscapes that have been extensively cleared, modified or fragmented, and in Australia, predominantly in the southern temperate zone. We investigated how within-site vegetation attributes and landscape context attributes were related to bird species richness and composition in a chronosequence of post-mining rehabilitation sites within an otherwise intact landscape in tropical northern Australia. Our working hypothesis was that bird species richness in rehabilitating sites would be positively related to site vegetation structure and landscape context including (1) proximity to woodland and (2) the proportion of woodland within a 500-m buffer of rehabilitation sites. Within each of 67 sites, we sampled vegetation once and surveyed for birds eight times over 16 months. Landscape context variables were calculated using GIS. There were large differences between bird assemblages of woodland and rehabilitation sites and between age classes of rehabilitation. Bird assemblages were strongly related to site vegetation attributes across all rehabilitation sites. Proximity to woodland was only related to bird assemblages in rehabilitation sites older than 4 years old. We conclude that the relative importance of landscape context and site variables at any point in time will be a function of how closely vegetation within the revegetation site matches the habitat resource requirements of individual species.

Tools for exploring and communicating the impact of uncertainty on spatial prediction are urgently needed, particularly when projecting species distribu- tions to future conditions. 2 We provide a tool for simulating uncertainty, focusing on uncertainty due to data quality. We illustrate the use of the tool using a Tasmanian endemic species as a case study. Our simulations provide probabilistic, spatially expli- cit illustrations of the impact of uncertainty on model projections. We also illustrate differences in model projections using six different global climate models and two contrasting emissions scenarios. 3 Our case study results illustrate how different sources of uncertainty have different impacts on model output and how the geographic distribution of uncertainty can vary. 4 Synthesis and applications: We provide a conceptual framework for under- standing sources of uncertainty based on a review of potential sources of uncertainty in species distribution modelling; a tool for simulating uncer- tainty in species distribution models; and protocols for dealing with uncer- tainty due to climate models and emissions scenarios. Our tool provides a step forward in understanding and communicating the impacts of uncer- tainty on species distribution models under future climates which will be particularly helpful for informing discussions between researchers, policy makers, and conservation practitioners.

We identify policies that would provide a solid foundation in key international negotiations to ensure that primary forests persist into the 21st Century. A novel compilation of primary forest cover and other data revealed that protection of primary forests is a matter of global concern being equally distributed between developed and developing countries. Almost all (98%) of primary forest is found within 25 countries with around half in five developed ones (USA, Canada, Russia, Australia, and NZ). Only 22% of primary forest is found in IUCN Protected Areas Categories I‐VI, which is approximately 5% of preagriculture natural forest cover. Rates of deforestation and forest degradation are rapid and extensive, and the long-term integrity of primary forest cannot be assumed. We recommend four new actions that could be included in climate change, biodiversity, and sustainable development negotiations: (1) recognize primary forests as a matter of global concern within international negotiations; (2) incorporate primary forests into environmental accounting; (3) prioritize the principle of avoided loss; and (4) universally accept the important role of indigenous and community conserved areas. In the absence of specific policies for primary forest protection, their unique biodiversity values and ecosystem services will continue to erode.

This article addresses the two key themes of the 2012 United Nations Conference on Sustainable Development (Rio+20), taking an integrative perspective. The case is being made that a ‘green economy’ remains illusionary without major reforms of the UN system of global governance; and that reforms in governance require the implementation of a new economic vision. An integrative perspective requires a commonly shared moral basis, as exemplified by the Earth Charter.

Calls for threat management actions to protect biodiversity and restore ecosystem function are rarely coupled with costed and prioritized sets of management actions for use in decision making. We present a cost-effectiveness approach for prioritizing threat management to maximize the in situ protection of biodiversity per dollar spent. The approach draws on empirical data and expert knowledge of major threats to biodiversity, feasible threat management actions, and likely responses of biodiversity to a set of costed management scenarios. An application assessing 637 vertebrate wildlife species in the Kimberley region of north-western Australia suggests that the likely functional loss of 45 mammals, birds, and reptiles over the next 20 years can be averted by effectively managing fire, grazing, and invasive species for approximately AU$40 million per year. Our approach is flexible and may be useful for delivering transparent guidance for conserving species and ecosystems in other regions, including those where data is limited.

Summary A framework is presented for terrestrial conservation assessment that has been developed for Bush Heritage, an Australian non-profit organisation that manages land of outstanding conservation value through acquisition or working in partnership with other landowners. The framework is called Biodiversity Prediction using Ecological Processes and comprises seven conservation goals, with a set of candidate criteria and indicators for each goal. Particular emphasis is given to criteria that relate to habitat quality in addition to the more conventional focus on land quantity. The MCAS-S graphic user interface is used to help analyse the indicators and visualise the results in a transparent way that assists the decision-making process. The interface also allows indicators to be weighted differently, which among other things, allows analyses to reflect inter-regional differences in what represents high quality land. The framework was tested in a case study region (the Woodland region of south-eastern Australia), and the results reveal land that is potentially a priority for conservation investments. While the framework and case study results are indicative, and further analyses are required before they can be considered operational, the approach has potential application to other organisations in the private conservation sector.

A common approach to nature conservation is to identify and protect natural 'assets' such as ecosystems and threatened species. While such actions are essential, protection of assets will not be effective unless the ecological processes that sustain them are maintained. Here, we consider the role of ecological processes and the complementary perspective for conservation arising from an emphasis on process. Many kinds of ecological processes sustain biodiversity: including climatic processes, primary productivity, hydrological processes, formation of biophysical habitats, interactions between species, movements of organisms and natural disturbance regimes. Anthropogenic threats to conservation exert their influence by modifying or disrupting these processes. Such threats extend across tenures, they frequently occur offsite, they commonly induce non-linear responses, changes may be irreversible and the full consequences may not be experienced for lengthy periods. While many managers acknowledge these considerations in principle, there is much scope for greater recognition of ecological processes in nature conservation and greater emphasis on long time-frames and large spatial scales in conservation planning. Practical measures that promote ecological processes include: monitoring to determine the trajectory and rate of processes; incorporating surrogates for processes in conservation and restoration projects; specific interventions to manipulate and restore processes; and planning for the ecological future before options are foreclosed. The long-term conservation of biodiversity and the well-being of human society depend upon both the protection of natural assets and maintaining the integrity of the ecological processes that sustain them.

Aim Most approaches to conservation prioritization are focused on biodiversity features that are already threatened. While this is necessary in the face of accelerating anthropogenic threats, there have been calls to conserve large intact landscapes, often termed ’wilderness', to ensure the long-term persistence of biodiversity. In this study, we examine the consequences of directing conservation expenditure using a threat-based framework for wilderness conservation. Location The Australian continent. Methods We measured the degree of congruence between the extent of wilderness and the Australian protected area network in 2000 and 2006, which was established using a threat-based systematic planning framework. We also assessed priority areas for future reserve acquisitions identified by the Australian government under the current framework. Results In 2000, 14 of Australia's wilderness was under formal protection, while the protected area network covered only 8.5 of the continent, suggesting a historical bias towards wilderness protection. However, the expansion of the reserve system from 2000 to 2006 was biased towards non-wilderness areas. Moreover, 90 of the wilderness that was protected over this period comprised areas not primarily designated for biodiversity conservation. We found a significant (P < 0.05) negative relationship between bioregions considered to be a priority for future reserve prioritization and the amount of wilderness they contain. Main conclusions While there is an urgent need to overcome past biases in reserve network design so as to better protect poorly represented species and habitats, prioritization approaches should not become so reactive as to ignore the role that large, intact landscapes play in conserving biodiversity, especially in a time of human-induced climate change. This can be achieved by using current or future threats rather than past threats to prioritize areas, and by incorporating key ecological processes and costs of acquisition and management within the planning framework. © 2009 Blackwell Publishing Ltd.

Quantifying forest change in the tropics is important because of the role these forests play in the conservation of biodiversity and the global carbon cycle. One of the world’s largest remaining areas of tropical forest is located in Papua New Guinea. Here we show that change in its extent and condition has occurred to a greater extent than previously recorded. We assessed deforestation and forest degradation in Papua New Guinea by comparing a land-cover map from 1972 with a land-cover map created from nationwide high-resolution satellite imagery recorded since 2002. In 2002 there were 28,251,967 ha of tropical rain forest. Between 1972 and 2002, a net 15 percent of Papua New Guinea’s tropical forests were cleared and 8.8 percent were degraded through logging. The drivers of forest change have been concentrated within the accessible forest estate where a net 36 percent were degraded or deforested through both forestry and nonforestry processes. Since 1972, 13 percent of upper montane forests have also been lost. We estimate that over the period 1990–2002, overall rates of change generally increased and varied between 0.8 and 1.8 percent/yr, while rates in commercially accessible forest have been far higher—having varied between 1.1 and 3.4 percent/yr. These rates are far higher than those reported by the FAO over the same period. We conclude that rapid and substantial forest change has occurred in Papua New Guinea, with the major drivers being logging in the lowland forests and subsistence agriculture throughout the country with comparatively minor contributions from forest fires, plantation establishment, and mining.

Systematic conservation planning research has focused on designing systems of conservation areas that efficiently protect a comprehensive and representative set of species and habitats. Recently, there has been an emphasis on improving the adequacy of conservation area design to promote the persistence and future generation of biodiversity. Few studies have explored incorporating ecological and evolutionary processes into conservation planning assessments. Biodiversity in Australia is maintained and generated by numerous ecological and evolutionary processes at various spatial and temporal scales. We accommodated ecological and evolutionary processes in four ways: (1) using sub-catchments as planning units to facilitate the protection of the integrity and function of ecosystem processes occurring on a sub-catchment scale; (2) targeting one type of ecological refugia, drought refugia, which are critical for the persistence of many species during widespread drought; (3) targeting one type of evolutionary refugia which are important for maintaining and generating unique biota during long-term climatic changes; and (4) preferentially grouping priority areas along vegetated waterways to account for the importance of connected waterways and associated riparian areas in maintaining processes. We identified drought refugia, areas of relatively high and regular herbage production in arid and semiarid Australia, from estimates of gross primary productivity derived from satellite data. In this paper, we combined the novel incorporation of these processes with a more traditional framework of efficiently representing a comprehensive sample of biodiversity to identify spatial priorities across Australia. We explored the trade-offs between economic costs, representation targets, and connectivity. Priority areas that considered ecological and evolutionary processes were more connected along vegetated waterways and were identified for a small increase in economic cost. Priority areas for conservation investment are more likely to have long-term benefits to biodiversity if ecological and evolutionary processes are considered in their identification.

Aim To develop a systematic and generic framework for biogeographical regionalizations that can assist in reconciling different approaches and advance their application as a research tool. Location The Australian continent is used as a case study. Methods A review of approaches to biogeographical regionalization revealed two basic methodologies: the integrated survey method and the parametric approach. To help reconcile these different approaches, we propose a simple, four-step, flexible and generic framework. (1) Identification of the thematic foci from the three main themes (composition and evolutionary legacy; ecosystem drivers; ecosystem responses). (2) Proposal of a theory defining the purpose. (3) Application of a numeric agglomerative classification procedure that requires the user to make explicit assumptions about attributes, the number of classification groups, the spatial unit of analysis, and the metric for measuring the similarity of these units based on their attribute values. (4) Acquisition of spatial estimates of the required input attribute data. For this case study, an agglomerative classification strategy was applied using the functions within patn 3.03, a software package facilitating large-scale, multivariate pattern analysis. The input data to the classifications were continental coverages of 11 environmental variables and three indices of gross primary productivity stored at a grid cell resolution of c. 250 m. The spatial units of analysis were surface hydrological units (SHU), which were derived from a continental digital elevation model based on the contributing areas to stream segments or the area draining into a local sink where there is no organized drainage. The Minkowski series (Euclidean distance) was selected as the association measure to allow weightings to be applied to the variables. Results Two new biogeographical regionalizations of the Australian continent were generated. The first was an environmental domain classification, based on 11 climatic, terrain and soil attributes. This regionalization can be used to address hypotheses about the relationship between environmental distance and evolutionary processes. The classification produced 151 environmental groups. The second was a classification of primary productivity regimes based on estimates of the gross primary productivity of the vegetation cover calculated from moderate resolution imaging spectroradiometer (MODIS) normalized difference vegetation index (NDVI) data and estimates of radiation. This classification produced 50 groups, and can be used to examine hypotheses concerning productivity regimes and animal life-history strategies. The productivity classification does not capture all the properties related to biological carrying capacity, process rates and differences in the characteristic biodiversity of ecosystems. Some of these ecologically significant properties are captured by the environmental domain classification. Main conclusions Our framework can be applied to all terrestrial regions, and the necessary data for the analyses presented here are now available at global scales. As the spatial predictions generated by the classifications can be tested by comparison with independent data, the approach facilitates exploratory analysis and further hypothesis generation. Integration of the three themes in our framework will contribute to a more comprehensive approach to biogeography.

The importance of strongly interactive predators has been demonstrated in many ecosystems, and the maintenance or restoration of species interactions is a major priority in the global conservation of biodiversity. By limiting populations of prey and/or competitors, apex predators can increase the diversity of systems, often exerting influences that cascade through several trophic levels. In Australia, emerging evidence points increasingly towards the dingo (Canis lupus dingo) as a strongly interactive species that has profound effects on ecosystem function. Through predatory and competitive effects, dingoes can alter the abundance and function of mesopredators including the introduced red fox (Vulpes vulpes) and feral cat (Felis catus), and herbivores including the European rabbit (Oryctolagus cuniculus). These effects often benefit populations of native prey, and diversity and biomass of vegetation, but may not occur under all circumstances. For example, the social structure of dingoes is of great importance; a pack subject to minimal human interference regulates its own numbers, and such packs appear to have fewer undesirable impacts such as predation on livestock. Despite abundant observational evidence that the dingo is a strong interactor, there have been few attempts to test its ecological role experimentally. Given the well-recognized importance of species interactions to ecosystem function, it is imperative that such experiments be carried out. To do this, we propose three broad questions: (i) do dingoes limit the abundance of other predators or prey? (ii) do dingoes affect the ecological relationships of other predators or prey (e.g. by altering their spatial or temporal activity patterns)? and (iii) does the removal or reintroduction of dingoes entrain ecological cascades? Finally, we discuss the design of appropriate experiments, using principles that may also be applied to investigate species interactions on other continents. Research might seek to clarify not only the impacts of dingoes at all trophic levels, but also the mechanisms by which these impacts occur.

Summary 1. The concept of assessing forests for carbon sequestration is well established. Operationally, estimating a forests’ potential to sequester carbon requires comparing its current carbon state with a prediction of its carbon carrying capacity (CCC). Assessment of CCC is, however, problematic. Mathematical models can be used, although traditional modelling techniques, where parameters are estimated from empirical measurements, are usually limited by a lack of field data. For example, estimates of carbon residency times in vegetation and soil are not generally available, nor are they easily measured. Alternative methods are required. 2. Current carbon stocks in 17 previously logged field sites were measured by field survey. CCC for those sites was then predicted using a terrestrial carbon model, calibrated with measurements from mature, unlogged vegetation of a comparable forest type. Model parameters were estimated using ‘model‐data fusion’ methods, where the model is inverted and field measurements of the carbon stocks (the model outputs) are used to calibrate the model parameters. Spatial variation was included through functions defining landscape-scale effects on plant growth relating to topographic influences on light and soil water availability. 3. Current above-ground carbon stocks (living plus litter) varied with management history, averaging 273 ± 30 tC ha − 1 (mean ± SE). Model-predicted CCC was 445 ± 13 tC ha − 1 , yielding a carbon sequestration potential of 172 ± 31 tC ha − 1 . Model simulations predicted the recovery of an average site to take 53 years to reach 75% carrying capacity, and 152 years to reach 90% carrying capacity. Extrapolation of these results to 7 Mha of comparable managed forests in the same region suggested a potential carbon sink of 680‐895 Mt C. 4. Synthesis and applications . In this study we have demonstrated that forests recovering from prior logging have the potential to store significant amounts of carbon, with current biomass stocks estimated to be approximately 60% of their predicted carrying capacity, a value similar to those reported for northern temperate forests. Although sequestration activities often focus on the aforestation and reforestation of previously cleared land, our results suggest that, where appropriate, native forest management should also be considered when developing terrestrial carbon management options, and for terrestrial carbon accounting more generally.

The WildCountry program boldly aims to offer 'a future for Australia's wilderness and biodiversity throughout and beyond the 21st Century'. This is to be achieved through building partnerships - one of the most important being a formal partnership with ecologists.

Aim A hierarchical framework is presented for modelling the spatial distribution of terrestrial vertebrate animals. Location The location of the study is the montane ash forests of the Central Highlands of Victoria, south-eastern Australia. Methods The framework is illustrated using as a case study the distribution of Leadbeater’s Possum [Gymnobelideus leadbeateri McCoy, 1867, (Marsupialia: Petauridae)], a small arboreal marsupial. The framework is based upon quantifying the environmental response of a species in terms of a five-level environmental hierarchy defined by scales (global-, meso-, topo-, micro- and nano-scales) that represent natural breaks in the distribution and availability of the primary environmental resources. Animal response is examined in terms of a species’ distribution as observed in four biological units (the species in toto, meta-population/population, group/colony, and individual organism). We define the spatial occurrence and abundance of the target species in each of these units as its ‘distributional behaviour’. Results Predictions of the potential spatial distribution of Leadbeater’s Possum are presented at meso-, topo-, micro- and nano-scales. These spatial predictions utilize Geographical Information System (GIS)-based spatial models of long term mean monthly climate and terrain-modified surface radiation, together with vegetation cover and individual tree attributes from air-photo interpretation and field survey. Main conclusions Ideally, species’ responses at each level in the environmental hierarchy should be empirically derived using statistical models based on field observation of a species’ distribution and abundance. Spatial modelling of species’ responses becomes problematic at finer scales because of the lack of suitable environmental data. The key characteristics of the modelling framework are generic, but the influence of additional scales and processes will be important in other ecosystems and species.

Aim This study identified the factors influencing the presence, stocking rate and basal area of the southern Australian cool temperate rain forest tree myrtle beech (Nothofagus cunninghamii). Location This investigation was conducted in the montane ash forests of the Central Highlands of Victoria, south-eastern Australia. Methods The occurrence of N. cunninghamii was measured as part of field surveys of 474 sites (2844 plots) distributed widely throughout mountain ash (Eucalyptus regnans), alpine ash (E. delegatensis) and shining gum (E. nitens) forests. Statistical analysis was employed to examine relationships between the occurrence of N. cunninghamii and measured site attributes and interpolated and derived environmental variables. Results The presence of N. cunninghamii was significantly related to five variables: the age of the overstorey eucalypt stand, dominant species of overstorey eucalypt tree, topographic position in the landscape, slope and the estimated quantity of precipitation in the warmest quarter of the year. N. cunninghamii was more likely to occur in old growth eucalypt stands, in gullies and locations with high values for rainfall in the warmest quarter. In addition, there was an interaction between slope and dominant eucalypt tree species-in forests dominated by E. regnans, N. cunninghamii was more likely to occur on steep slopes whereas in E. nitens and E. delegatensis-dominated stands, N. cunninghamii was more likely to occur on flatter terrain. Statistical modelling also showed a significant positive effect of slope on both the stocking rate and basal area of the species. The stocking rate of N. cunninghamii also was significantly higher in old growth eucalypt stands. Main conclusions The study demonstrated that the patterns of distribution of N. cunninghamii may be more complex than recognized previously and it illustrated the importance of multiple factors including climatic conditions, disturbance processes (as reflected through the age of the dominant overstorey eucalypt stands) and topography. Our work also shows there can be complex interactions between age cohorts of different tree species in the same stand-in this case, the dominant overstorey eucalypts and the understorey which includes N. cunninghamii stems.

Species distribution models (SDMs) are commonly used to project future changes in the geographic ranges of species, to estimate extinction rates and to plan biodiversity conservation. However, these models can produce a range of results depending on how they are parameterized, and over-reliance on a single model may lead to overconfidence in maps of future distributions. The choice of predictor variable can have a greater influence on projected future habitat than the range of climate models used. We demonstrate this in the case of the Ptunarra Brown Butterfly, a species listed as vulnerable in Tasmania, Australia. We use the Maxent model to develop future projections for this species based on three variable sets; all 35 commonly used so-called ‘bioclimatic’ variables, a subset of these based on expert knowledge, and a set of monthly climate variables relevant to the species’ primary activity period. We used a dynamically downscaled regional climate model based on three global climate models. Depending on the choice of variable set, the species is projected either to experience very little contraction of habitat or to come close to extinction by the end of the century due to lack of suitable climate. The different conclusions could have important consequences for conservation planning and management, including the perceived viability of habitat restoration. The output of SDMs should therefore be used to define the range of possible trajectories a species may be on, and ongoing monitoring used to inform management as changes occur.

Models are reviewed that predict the potential distribution of classes of rain-forest structural characteristics in relation to indices of climate and soil parent material. A description is given of the field survey undertaken to examine these relations in the Wet Tropics of Queensland, Australia. The predicted probabilities are compared with the observed values and the extent of correspondence between the two data sets examined. Environmental relations based on finer-scaled landscape processes are proposed to explain the mismatches. An index of catchment hydrology is described that represents the most feasible additional independent variable for spatial extension purposes.

Evaluating contributions of forest ecosystems to climate change mitigation requires well-calibrated carbon cycle models with quantified baseline carbon stocks. An appropriate baseline for carbon accounting of natural forests at landscape scales is carbon carrying capacity (CCC); defined as the mass of carbon stored in an ecosystem under prevailing environmental conditions and natural disturbance regimes but excluding anthropogenic disturbance. Carbon models require empirical measurements for input and calibration, such as net primary production (NPP) and total ecosystem carbon stock (equivalent to CCC at equilibrium). We sought to improve model calibration by addressing three sources of errors that cause uncertainty in carbon accounting across heterogeneous landscapes: (1) data-model representation, (2) data-object representation, (3) up-scaling. We derived spatially explicit empirical models based on environmental variables across landscape scales to estimate NPP (based on a synthesis of global site data of NPP and gross primary productivity, n = 27), and CCC (based on site data of carbon stocks in natural eucalypt forests of southeast Australia, n = 284). The models significantly improved predictions, each accounting for 51 % of the variance. Our methods to reduce uncertainty in baseline carbon stocks, such as using appropriate calibration data from sites with minimal human disturbance, measurements of large trees and incorporating environmental variability across the landscape, have generic application to other regions and ecosystem types. These analyses resulted in forest CCC in southeast Australia (mean total biomass of 360 t C ha -1 , with cool moist temperate forests up to 1000 t C ha -1 ) that are larger than estimates from other national and international (average biome 202 t C ha -1 ) carbon accounting systems. Reducing uncertainty in estimates of carbon stocks in natural forests is important to allow accurate accounting for losses of carbon due to human activities and sequestration of carbon by forest growth.

Management of native forests offers opportunities to store more carbon in the land sector through two main activities. Emissions to the atmosphere can be avoided by ceasing logging. Removals of arbon dioxide from the atmosphere can be increased by allowing forests to continue growing. However, the relative benefits for carbon storage of managing native forests for wood production versus protection are contested. Additionally, the potential for carbon storage is impacted upon by disturbance events, such as wildfire, that alter the amount and longevity of carbon stocks. Using a case study of montane ash forests in southeastern Australia, we demonstrated that the total biomass carbon stock in logged forest was 55% of the stock in old growth forest. Total biomass included above- and belowground, living and dead. Biomass carbon stock was calculated spatially as an average across the landscape, accounting for variation in environmental conditions and forest age distribution. Reduction in carbon stock in logged forest was due to 66% of the initial biomass being made into products with short lifetimes (,3 years), and to the lower average age of logged forest (,50 years compared with 100 years in old growth forest). Only 4% of the initial carbon stock in the native forest was converted to sawn timber products with lifetimes of 30-90 years. Carbon stocks are depleted in a harvested forest system compared with an old growth forest, even when storage in wood products and landfill are included. We estimated that continued logging under current plans represented a loss of 5.56 Tg C over 5 years in the area logged (824 km2), compared with a potential gain of 5.18-6.05 TgC over 5 years by allowing continued growth across the montane ash forest region (2326 km2). Avoiding emissions by not logging native forests and allowing them to continue growing is therefore an important form of carbon sequestration. The mitigation value of forest management options of protection versus logging should be assessed in terms of the amount, longevity and resilience of the carbon stored in the forest, rather than the annual rate of carbon uptake.