Biodiversity offsetting is a globally influential policy mechanism for reconciling trade-offs between development and biodiversity loss. However, there is little robust evidence of its effectiveness. We evaluated the outcomes of a jurisdictional offsetting policy (Victoria, Australia). Offsets under Victoria’s Native Vegetation Framework (2002–2013) aimed to prevent loss and degradation of remnant vegetation, and generate gains in vegetation extent and quality. We categorised offsets into those with near-complete baseline woody vegetation cover (“avoided loss”, 2702 ha) and with incomplete cover (“regeneration”, 501 ha), and evaluated impacts on woody vegetation extent from 2008 to 2018. We used two approaches to estimate the counterfactual. First, we used statistical matching on biophysical covariates: a common approach in conservation impact evaluation, but which risks ignoring potentially important psychosocial confounders. Second, we compared changes in offsets with changes in sites that were not offsets for the study duration but were later enrolled as offsets, to partially account for self-selection bias (where landholders enrolling land may have shared characteristics affecting how they manage land). Matching on biophysical covariates, we estimated that regeneration offsets increased woody vegetation extent by 1.9%–3.6%/year more than non-offset sites (138–180 ha from 2008 to 2018) but this effect weakened with the second approach (0.3%–1.9%/year more than non-offset sites; 19–97 ha from 2008 to 2018) and disappeared when a single outlier land parcel was removed. Neither approach detected any impact of avoided loss offsets. We cannot conclusively demonstrate whether the policy goal of ‘net gain’ (NG) was achieved because of data limitations. However, given our evidence that the majority of increases in woody vegetation extent were not additional (would have happened without the scheme), a NG outcome seems unlikely. The results highlight the importance of considering self-selection bias in the design and evaluation of regulatory biodiversity offsetting policy, and the challenges of conducting robust impact evaluations of jurisdictional biodiversity offsetting policies.
Country: Australia
Australia
As cities increasingly turn to nature-based solutions to address key urban socio-ecological challenges, approaches to their governance, planning and implementation are increasingly important for ensuring their effectiveness. Nature-based solutions are multifunctional, and so their planning and implementation are by necessity interdisciplinary. As such, to support urban transitions with nature-based solutions, the role of intermediary actors deserves research attention. Intermediaries play key roles in linking between sectors, across different levels of government and between disciplines and policy domains. We identified three key points for research and planning nature-based solutions through intermediaries as key agents for change: intermediaries are creators of enabling institutional spaces needed for mainstreaming nature-based solutions in cities; intermediaries as actor configurations are dynamic over time and in context, and intermediation has to be understood as a fundamental governance activity in cities that want to scale up their climate adaptation planning with nature-based solutions. Using a case study of the development and initial implementation of the metropolitan urban forest strategy in Melbourne Australia, we analyze the multi-actor landscape that emerged, through the lens of intermediation. We systematically investigated which actors, partnerships and platforms acted as intermediaries in the transformative agenda of the Urban Forest strategy, how these actors interacted over the course of the strategy’s development and how their roles and functions shifted during the early implementation stages of the strategy. We found that an ‘ecology of intermediaries’ adopted a range of roles to support key functions including building collaboration, informing and disseminating policy learning, and strengthening political support. While intermediaries’ roles and functions shifted across the strategy’s development, their contributions were critical in the complex metropolitan governance context. Collaborative planning and governance for nature-based solutions in cities require intermediaries to remain topical, focused and inclusive/open to new ideas and lessons from innovations both emerging and driven.
Climate change poses significant emerging risks to biodiversity, ecosystem function and associated socioecological systems. Adaptation responses must be initiated in parallel with mitigation efforts, but resources are limited. As climate risks are not distributed equally across taxa, ecosystems and processes, strategic prioritization of research that addresses stakeholder‐relevant knowledge gaps will accelerate effective uptake into adaptation policy and management action. After a decade of climate change adaptation research within the Australian National Climate Change Adaptation Research Facility, we synthesize the National Adaptation Research Plans for marine, terrestrial and freshwater ecosystems. We identify the key, globally relevant priorities for ongoing research relevant to informing adaptation policy and environmental management aimed at maximizing the resilience of natural ecosystems to climate change. Informed by both global literature and an extensive stakeholder consultation across all ecosystems, sectors and regions in Australia, involving thousands of participants, we suggest 18 priority research topics based on their significance, urgency, technical and economic feasibility, existing knowledge gaps and potential for cobenefits across multiple sectors. These research priorities provide a unified guide for policymakers, funding organizations and researchers to strategically direct resources, maximize stakeholder uptake of resulting knowledge and minimize the impacts of climate change on natural ecosystems. Given the pace of climate change, it is imperative that we inform and accelerate adaptation progress in all regions around the world.
In view of past environmental degradation and anticipated climate change impacts, we assessed the potential for ecosystem-based adaptation in the Murray-Darling Basin, Australia. In a workshop with staff from three Catchment Management Authorities (CMAs) who had jurisdiction over three sub-basins, as well as technical experts, nine adaptation options were identified that ranged from environmental flows, restoring river channel habitat, reoperating infrastructure and controlling invasive species. A Catchment Adaptation Framework was developed and used to assess and compare these adaptation options with each of the CMAs, drawing on interviews with their key stakeholders, to identify the risks, benefits and costs. We found that ecosystem-based adaptation can augment catchment management programs and requires investment in a suite of different but complementary measures to lower risk. Our research found institutional challenges in implementing this approach, including the complexities of multi-agency management, constricting legal requirements, narrow funding arrangements, under-developed institutional capacity, difficulties of implementing catchment-scale programs on private property and the need to adhere to community expectations. These institutional issues are ubiquitous internationally and point to the wider issues of providing sufficient management capacity to support adaptation. The Catchment Adaptation Framework presented here enables river basin managers to systematically assess the adaptation options to better inform their decision-making.
Ecosystem services are typically valued for their immediate material or cultural benefits to human wellbeing, supported by regulating and supporting services. Under climate change, with more frequent stresses and novel shocks, ‘climate adaptation services’, are defined as the benefits to people from increased social ability to respond to change, provided by the capability of ecosystems to moderate and adapt to climate change and variability. They broaden the ecosystem services framework to assist decision makers in planning for an uncertain future with new choices and options. We present a generic framework for operationalising the adaptation services concept. Four steps guide the identification of intrinsic ecological mechanisms that facilitate the maintenance and emergence of ecosystem services during periods of change, and so materialise as adaptation services. We applied this framework for four contrasted Australian ecosystems. Comparative analyses enabled by the operational framework suggest that adaptation services that emerge during trajectories of ecological change are supported by common mechanisms: vegetation structural diversity, the role of keystone species or functional groups, response diversity and landscape connectivity, which underpin the persistence of function and the reassembly of ecological communities under severe climate change and variability. Such understanding should guide ecosystem management towards adaptation planning.
Climate change is occurring and not being mitigated, motivating adaptation but adaptation strategies can have biophysical, economic, technological, and social limits. We review publicly available documents to assess how successful current and proposed adaptation strategies may be for the Australian Alps, including likely limits and potential collaborations and conflicts among stakeholders. Conservation managers, the tourism industry, and local communities have implemented or are proposing a range of adaptation strategies in the region. Some stakeholder strategies complement each other (e.g. invasive species control, fire management), while others are potential sources of conflict (water and electricity for snowmaking, year-round tourism). Economic costs and biophysical constraints are the most important limits to these adaptation strategies. These types of limits and conflicts between different stakeholders on adaptation strategies are likely to occur in other regions and demonstrate that adaptation may only provide partial and short term solutions to the challenges of climate change.
Conflict over water allocations and the need to adapt to climate change in Australia’s Murray-Darling Basin has resulted in decision makers choosing engineering interventions to use water more efficiently for wetlands conservation. We review a range of policy and infrastructure adaptation measures implemented in the Basin by governments. The water supply and demand “environmental works and measures” adopted in the Coorong and Lower Lakes region, as well as along the River Murray, are assessed and compared with the opportunity costs for ecosystem-based adaptation. The results suggest that risks of disruption to ecological processes, desiccation of wetland areas and institutional failure with infrastructure-led adaptation measures are little appreciated. Further, ecosystem-based measures to maintain a more diverse range of ecological processes that would spread risk and conserve a more diverse range of biota have not been identified or adopted by governments. We conclude that as a primary adaptation to climate change environmental works and measures may represent overly-narrow or mal-adaptation that can reduce the resilience of wetland ecosystems.
Global biodiversity hotspots contain exceptional concentrations of endemic species in areas of escalating habitat loss. However, most hotspots are geographically constrained and consequently vulnerable to climate change as there is limited ability for the movement of species to less hostile conditions. Predicted changes to rainfall and temperature will undoubtedly further impact on freshwater ecosystems in these hotspots. Southwestern Australia is a biodiversity hotspot and, as one of the first to experience significant climate change, is an example and potentially a global bellwether for issues associated with river restoration. In this hotspot, current and predicted water temperatures may exceed thermal tolerances of aquatic fauna. Gondwanic aquatic fauna, characteristic of southwestern Australia, are typically cold stenotherms and consequently intolerant of elevated temperatures. The hotspot in southwestern Australia is geographically restricted being surrounded by ocean and desert, and many important national parks are located on the extreme south coast, where the landscape is relatively flat. Consequently, fauna cannot change their distribution southwards or with altitude as a response to increasing temperatures. Therefore, any mitigation responses need to be in situ to produce a suitable biophysical envelope to enhance species’ resilience. This could be through “over restoration” by increased riparian replanting at a catchment scale. A rule-of-thumb of a 10% increase in riparian cover would be required to reduce water temperatures by 1°C. These restoration techniques are considered applicable to other global biodiversity hotspots where geography constrains species’ movement and the present condition is the desired restoration endpoint.
Replanting native vegetation is a broadly accepted method for restoring degraded landscapes. Traditionally, seed used for restoration has been locally sourced to avoid introducing maladapted plants and to minimize the risk of outbreeding depression. However local adaptation is not universal and is disrupted by, for example, climate change and habitat fragmentation. We established a common garden experiment of ca. 1500 seedlings sourced from one local and two non-local provenances of Eucalyptus leucoxylon to test whether local provenancing was appropriate. The three provenances spanned an aridity gradient, with the local provenance sourced from the most mesic area. We explored the effect of provenance on four fitness proxies after 15 months, including survival, above-ground height, susceptibility to insect herbivory, and pathogen related stress. The local provenance had the highest mortality and grew least. The local provenance also suffered most from invertebrate herbivory and pathogen related stress. These results provide evidence that no advantage would be gained during the establishment of Eucalyptus leucoxylon at this site by using only the local provenance from within the range we sampled. Our results suggest that incorporating more diverse seed mixes from across the aridity gradient during the restoration of Eucalyptus leucoxylon open woodlands would provide quantifiable benefits to restoration (e.g. 6–10% greater survival, 20–25% greater plant height, 16–45% more pathogen resistance during establishment). We demonstrated these restoration gains by embedding a common garden experiments into a restoration project, and we recommend this approach be more widely adopted because it provides an effective way to facilitate adaptive management options for restoration stakeholders based on empirical evidence.
Anthropogenic change (climate change and habitat fragmentation) is driving a growing view that local seed collections may need to be supplemented with nonlocal seed as a strategy to bolster genetic diversity and thus increase evolutionary potential of plantings. While this strategy is becoming widely promoted, empirical support is limited, and there is a lack of accessible research tools to assist in its experimental testing. We therefore provide the Provenancing Using Climate Analogues (PUCA) framework that integrates the principles of the climate-adjusted provenancing strategy with concepts from population genetics (i.e. potential inbreeding in small fragmented populations) as both a research and operational-ready tool to guide the collection of nonlocal seed. We demonstrate the application of PUCA using the Midlands of Tasmania, Australia, a region that is currently undergoing large-scale ecological restoration. We highlight multiple nonlocal seed sources for testing by identifying actual species distribution records that currently occupy environments similar to that projected to occur at the restoration site in the future. We discuss the assumptions of PUCA and the ecological considerations that need to be tested when moving nonlocal genotypes across the landscape.
As a consequence of global climate-driven changes, marine ecosystems are experiencing polewards redistributions of species – or range shifts – across taxa and throughout latitudes worldwide. Research on these range shifts largely focuses on understanding and predicting changes in the distribution of individual species. The ecological effects of marine range shifts on ecosystem structure and functioning, as well as human coastal communities, can be large, yet remain difficult to anticipate and manage. Here, we use qualitative modelling of system feedback to understand the cumulative impacts of multiple species shifts in south-eastern Australia, a global hotspot for ocean warming. We identify range-shifting species that can induce trophic cascades and affect ecosystem dynamics and productivity, and evaluate the potential effectiveness of alternative management interventions to mitigate these impacts. Our results suggest that the negative ecological impacts of multiple simultaneous range shifts generally add up. Thus, implementing whole-of-ecosystem management strategies and regular monitoring of range-shifting species of ecological concern are necessary to effectively intervene against undesirable consequences of marine range shifts at the regional scale. Our study illustrates how modelling system feedback with only limited qualitative information about ecosystem structure and range-shifting species can predict ecological consequences of multiple co-occurring range shifts, guide ecosystem-based adaptation to climate change and help prioritise future research and monitoring.
Freshwater ecosystems in many parts of the world have been severely affected by past management practices that have altered the volume, timing and quality of water flows and caused a decline in their ecological health. Some of these systems are also experiencing the negative impacts of climate change. Adaptation to climate change and the continual need to address existing ecological damage poses ongoing challenges for freshwater managers. In this paper we propose and discuss a Catchment Assessment Framework (CAF) that is used to evaluate existing and potential freshwater management actions, such as riparian revegetation and habitat connectivity, for their adaptation potential. The CAF was developed as a tool for prioritizing low risk climate change adaptation options in Australian catchment management. The CAF enables catchment managers and technical experts to assess management actions against seven inter-related criteria to provide a holistic assessment: relevance to the catchment; climate change adaptation potential, including potential for maladaptation and benefit under different climate scenarios; ecosystem service benefits; compatibility with other actions; implementation constraints; socio-economic consequences; and a risk assessment. It was developed and applied by assessing nine management options with stakeholders in three catchments within the Murray-Darling Basin in south-eastern Australia. We found that while management options are undertaken as a response to existing degradation, they can be used as building blocks for a climate change adaptation strategy that considers a range of different but complementary measures to better manage climate-related risk. The CAF enables practitioners to assess the advantages of a range of adaptation options and to subject them to their wider decision making and management planning.