Vulnerability assessments have often invoked sustainable livelihoods theory to support the quantification of adaptive capacity based on the availability of capital--social, human, physical, natural, and financial. However, the assumption that increased availability of these capitals confers greater adaptive capacity remains largely untested. We quantified the relationship between commonly used capital indicators and an empirical index of adaptive capacity (ACI) in the context of vulnerability of Australian wheat production to climate variability and change. We calculated ACI by comparing actual yields from farm survey data to climate-driven expected yields estimated by a crop model for 12 regions in Australia's wheat-sheep zone from 1991-2010. We then compiled data for 24 typical indicators used in vulnerability analyses, spanning the five capitals. We analyzed the ACI and used regression techniques to identify related capital indicators. Between regions, mean ACI was not significantly different but variance over time was. ACI was higher in dry years and lower in wet years suggesting that farm adaptive strategies are geared towards mitigating losses rather than capitalizing on opportunity. Only six of the 24 capital indicators were significantly related to adaptive capacity in a way predicted by theory. Another four indicators were significantly related to adaptive capacity but of the opposite sign, countering our theory-driven expectation. We conclude that the deductive, theory-based use of capitals to define adaptive capacity and vulnerability should be more circumspect. Assessments need to be more evidence-based, first testing the relevance and influence of capital metrics on adaptive capacity for the specific system of interest. This will more effectively direct policy and targeting of investment to mitigate agro-climatic vulnerability.
Compelling evidence shows that trees and greenspaces positively impact human well-being and the environment and offer economic benefits. Nevertheless, there exists a knowledge gap regarding the extent to which this evidence is efficiently incorporated into existing urban planning decision-making processes. This scoping review identified the extent to which urban planning decision-making frameworks, models, and tools consider the health, environmental, and economic benefits of trees and greenspace. Out of 28 reviewed studies, 11 (39%) reported on frameworks, models, and tools that take into account the health, environmental, and economic dimensions of trees and greenspace. Additionally, seven studies provided comprehensive coverage of at least one of the three key dimensions. However, none of the decision support frameworks, models, or tools comprehensively integrated all three dimensions, with only two tools (7%) scoring above 50% (five or more out of nine) in terms of comprehensiveness. This review highlights the urgent need to incorporate the true economic and monetary values of the health and environmental benefits of trees and greenspace to inform urban development decision making.
Under the multibarrier paradigm, water quality management barriers that mitigate risk to consumers are required at multiple points from the catchment to the tap . We present a cost‐effectiveness analysis of 13 catchment‐ and treatment‐based management alternatives for mitigating Cryptosporidium risk in the Myponga water supply catchment, South Australia. A broad range of costs and benefits are identified and valued, including setup, operation and maintenance, and opportunity costs, and benefits for ecosystem services including water quality, biodiversity, carbon sequestration, and farm production services. The results suggest that the cost‐effectiveness of investment in water quality management can be substantially enhanced by considering the costs of management and the benefits for ecosystem services, in addition to Cryptosporidium removal effectiveness. Cost‐effectiveness of investment in management alternatives is dependent upon the desired level of Cryptosporidium removal effectiveness by both the catchment and treatment barriers. The combination of a spatially targeted 25% restriction in water course access of nondairy cattle and treatment by enhanced coagulation provides the most (net) cost‐effective Cryptosporidium risk mitigation strategy. This combination may achieve 0.614 log removal at a net cost of A$0.7 million and (net) cost‐effectiveness of A$1.14 million per log removal. Additional risk mitigation can be achieved through the addition of ultraviolet irradiation treatment, higher levels of water course access restriction for cattle, and the adoption of dung beetles in the catchment. Economic valuation of a range of costs and benefits of management priorities can support cost‐effective water quality management investment decisions and inform elements of policy design such as cost‐sharing arrangements and spatial targeting.