The outlook of the Great Barrier Reef (GBR) was recently assessed as poor and declining (Great Barrier Reef Marine Park Authority [GBRMPA], 2014a; GBRMPA, 2014b). Impacts on the Region’s values do not occur in isolation but overlap in time and space, thus reducing the overall resilience and health of the Reef. Understanding cumulative pressures and their impacts has become a priority for environmental policy, management and conservation globally. In Australia, a fuller understanding of cumulative impacts from global and local stressors, and the ability to attribute those impacts to specific drivers and activities, is now a priority, as reflected in the Reef 2050 Long-Term Sustainability Plan. Despite such prioritisation, reef managers currently rely largely on qualitative tools to assess risks from cumulative impacts associated with development proposals (GBRMPA, 2009).
This Report focuses on coral reef environments and provides: (i) a comprehensive review and synthesis of existing tools and qualitative and quantitative studies that describe the cumulative impacts of local and global pressures on reef organisms and processes, (ii) an overview of important knowledge gaps and future research priorities, and (iii) a roadmap to develop a practical framework (incorporating quantitative approaches for assessing risk of multiple stressors) to support the assessment and management of cumulative impacts on the GBR.
To provide a clearer understanding of the concepts and problems around the science of cumulative impacts on coral reef environments, we reviewed and evaluated the existing knowledge of the cumulative effects of specific pressure combinations. This review also identified essential gaps in the information needed to guide effective management decisions and potential solutions.