Identifying low risk climate change adaptation in catchment management while avoiding unintended consequences

Inherent in every adaptation measure are risks, costs and benefits. A challenge for decision-makers is how to choose adaptations that reduce risks from climate change impacts and provide overwhelmingly beneficial outcomes. This project focused on three catchments in the Murray-Darling Basin to test a method for more integrative climate change adaptation that increased resilience and avoided maladaptation. Water management under the highly variable Murray-Darling Basin climate has lessons and broad implications for climate policies, especially as some of the proposed climate change adaptation measures for ecosystems and water resources are overly narrow or maladaptive, and have a high risk of institutional failure. We brought together a range of experts and Catchment Management Authority (CMA) representatives from the Goulburn-Broken, Lachlan and NSW Murray catchments to synthesise and integrate the risks, costs and benefits of climate change adaptation measures and assess the extent to which they may represent maladaptation or contribute to adaptation and resilience. Specific methods included a literature review; a three-day technical workshop with representatives from the three CMAs as well as technical experts from academic institutions and government departments; three stakeholder workshops with the CMAs; and semi-structured interviews with 20 key stakeholder representatives in each case study. Limitations of this approach, mainly due to timing and financial constraints, included small sample sizes for the interviews, a CMA-only focus, reliance on expert opinion and limited opportunity to further test the results. By working with the CMAs, we: • showed how systemic climate change adaptation planning can better consider risks, costs and benefits to inform choice of measures • produced research data on climate change adaptation options in specific catchments in southern Australia • identified current stakeholder understanding of the complex issue of climate change adaptation at a catchment level • confirmed the usefulness of an ‘ecosystem-based approach’ for climate change adaptation • developed a ‘CCA Catchment Assessment Framework’ as a tool for regional management bodies in southern Australia to assess climate change adaptation. The key lessons that emerged from this research are presented below. First, there are many activities underway that, if extended and linked, would comprise a substantial ecosystem-based approach to adaptation. It is notable that many of these activities had not previously been considered in an adaptation context. Second, the research confirmed the need to look at a suite of complementary actions that spread risk rather than investing in one or two perceived best actions. Third, the adoption of an ecosystem-based approach is constrained by institutional complexity and socioeconomic considerations that should be included in assessments of climate change adaptation. Finally, adaptive management provides a basis for the implementation of an ecosystem-based approach to climate change adaptationInherent in every adaptation measure are risks, costs and benefits. A challenge for decision-makers is how to choose adaptations that reduce risks from climate change impacts and provide overwhelmingly beneficial outcomes. This project focused on three catchments in the Murray-Darling Basin to test a method for more integrative climate change adaptation that increased resilience and avoided maladaptation. Water management under the highly variable Murray-Darling Basin climate has lessons and broad implications for climate policies, especially as some of the proposed climate change adaptation measures for ecosystems and water resources are overly narrow or maladaptive, and have a high risk of institutional failure. We brought together a range of experts and Catchment Management Authority (CMA) representatives from the Goulburn-Broken, Lachlan and NSW Murray catchments to synthesise and integrate the risks, costs and benefits of climate change adaptation measures and assess the extent to which they may represent maladaptation or contribute to adaptation and resilience. Specific methods included a literature review; a three-day technical workshop with representatives from the three CMAs as well as technical experts from academic institutions and government departments; three stakeholder workshops with the CMAs; and semi-structured interviews with 20 key stakeholder representatives in each case study. Limitations of this approach, mainly due to timing and financial constraints, included small sample sizes for the interviews, a CMA-only focus, reliance on expert opinion and limited opportunity to further test the results. By working with the CMAs, we: • showed how systemic climate change adaptation planning can better consider risks, costs and benefits to inform choice of measures • produced research data on climate change adaptation options in specific catchments in southern Australia • identified current stakeholder understanding of the complex issue of climate change adaptation at a catchment level • confirmed the usefulness of an ‘ecosystem-based approach’ for climate change adaptation • developed a ‘CCA Catchment Assessment Framework’ as a tool for regional management bodies in southern Australia to assess climate change adaptation. The key lessons that emerged from this research are presented below. First, there are many activities underway that, if extended and linked, would comprise a substantial ecosystem-based approach to adaptation. It is notable that many of these activities had not previously been considered in an adaptation context. Second, the research confirmed the need to look at a suite of complementary actions that spread risk rather than investing in one or two perceived best actions. Third, the adoption of an ecosystem-based approach is constrained by institutional complexity and socioeconomic considerations that should be included in assessments of climate change adaptation. Finally, adaptive management provides a basis for the implementation of an ecosystem-based approach to climate change adaptatio

Ramsar Wetlands of International Importance–improving conservation outcomes

The Ramsar Convention (or the Convention on Wetlands), signed in 1971, was one of the first international conservation agreements, promoting global wise use of wetlands. It has three primary objectives: national designation and management of wetlands of international importance; general wise use of wetlands; and international cooperation. We examined lessons learnt for improving wetland conservation after Ramsar’s nearly five decades of operation. The number of wetlands in the Ramsar Site Network has grown over time (2,391 Ramsar Sites, 2.5 million km2, as at 2020-06-09) but unevenly around the world, with decreasing rate of growth in recent decades. Ramsar Sites are concentrated in countries with a high Gross Domestic Product and human pressure (e.g., western Europe) but, in contrast, Ramsar Sites with the largest wetland extent are in central-west Africa and South America. We identified three key challenges for improving effectiveness of the Ramsar Site Network: increasing number of sites and wetland area, improved representation (functional, geographical and biological); and effective management and reporting. Increasing the number of sites and area in the Ramsar network could benefit from targets, implemented at national scales. Knowledge of representativeness is inadequate, requiring analyses of functional ecotypes, geographical and biological representativeness. Finally, most countries have inadequate management planning and reporting on the ecological character of their Ramsar Sites, requiring more focused attention on a vision and objectives, with regular reporting of key indicators to guide management. There are increasing opportunities to rigorously track ecological character, utilizing new tools and available indicators (e.g., remote sensing). It is critical that the world protect its wetlands, with an effective Ramsar Convention or the Convention on Wetlands at the core

Global CO2 emissions from dry inland waters share common drivers across ecosystems

Many inland waters exhibit complete or partial desiccation, or have vanished due to global change, exposing sediments to the atmosphere. Yet, data on carbon dioxide (CO2) emissions from these sediments are too scarce to upscale emissions for global estimates or to understand their fundamental drivers. Here, we present the results of a global survey covering 196 dry inland waters across diverse ecosystem types and climate zones. We show that their CO2 emissions share fundamental drivers and constitute a substantial fraction of the carbon cycled by inland waters. CO2 emissions were consistent across ecosystem types and climate zones, with local characteristics explaining much of the variability. Accounting for such emissions increases global estimates of carbon emissions from inland waters by 6% (~0.12 Pg C y−1). Our results indicate that emissions from dry inland waters represent a significant and likely increasing component of the inland waters carbon cycle

Climate change adaptation in the Murray-Darling Basin: Reducing resilience of wetlands with engineering

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

Status of Wetlands in Northern Australia

Compared to southern Australia it is generally considered that wetlands in northern Australia are generally 'intact' and possibly close to 'pristine'. With the exception of a few specific areas we accept the comparison, but baulk at making a categorical statement that supports the\ud impression that northern wetlands are in good condition. Without getting into an esoteric debate about concepts we provide an analysis of pressures on northern wetlands and point to major concerns for the future. We do this by assessing the extent of wetland inventory information and recommend that a coordinated approach using standardised protocols and core data is needed to complete the picture and make this available to users. Further, ecological assessment, including structured risk assessment of pressures is urgently needed. This not only provides a considered base for management actions but also for further\ud prioritisation of research effort. We then identify major research topics that need to be addressed. \ud \ud Our analysis is essentially based on the biophysical features of northern wetlands. These are valuable and in some instances well known and protected. However, in order to conserve and ensure wise use of wetlands we contend that this approach is insufficient. We propose that a stronger emphasis be placed on sustainable use of the goods and services which wetlands provide humans. The challenge in doing this is to demonstrate through research activities that the provision of these goods and services is dependent on the maintenance of wetland habitats and their species. The case for doing this is illustrated through a framework relating goods and services to ecosystem components and thence to pressures that could degrade these, including the emerging pressures of globalisation of trade and global climate change, and the research required to understand these sufficiently well to support management responses