Capturing Expert Uncertainty in Impact Assessments in the Spencer Gulf

68
RESEARCH AREA
68

This week’s featured research article has just been published in Nature Scientific Reports by University of Adelaide researchers and examines how to capture expert uncertainty in spatial cumulative impact assessments in the Spencer Gulf, SA. The research, based in part on expert-elicited data, showed that the greatest risk of cumulative impacts to the eight assessed coastal and marine environments occurred in intertidal and shallow subtidal ecosystems, particularly in the northern Gulf. This was consistent across all expert score uncertainty scenarios and was due to: 1) greater concentrations of high-intensity threats in coastal areas, especially close to heavy industry and population centres; and 2) higher effect scores for these ecosystems (indicative of their greater vulnerability to threats), particularly climate change and localised pollution. Overall, however, only a relatively small proportion of Spencer Gulf’s marine ecosystems appear to be exposed to high risks from cumulative impact when qualitatively compared to published studies for other locations. This is a positive outcome, and means the results can be used to support conservation and proactive, protective management, rather than exclusively highlighting priority areas for restoration. The research shows that uncertainty associated with expert knowledge can lead to uncertainty in the outputs of spatial cumulative impact assessments. However, the researchers recognise the value of expert knowledge for assessments of data-poor regions and environments (commonly the case for marine systems). The researchers conclude that the study demonstrates a straight-forward method for capturing uncertainty in expert knowledge, which is simply to ask the experts for effect score ranges indicative of their uncertainty, when assessing the effect of threats to ecosystems. This approach then enables knowledge-based uncertainty to be accounted for and the most certain results to be identified. The article can be downloaded here (or email jennie.fluin@sa.gov.au for a copy).