2 posts tagged with "Cumulative Impact Mapping"

With increasing human population, large scale climate changes, and the interaction of multiple stressors, understanding cumulative effects on marine ecosystems is increasingly important. Two major drivers of change in coastal and marine ecosystems are industrial developments with acute impacts on local ecosystems, and global climate change stressors with widespread impacts. We conducted a cumulative effects mapping analysis of the marine waters of British Columbia, Canada, under different scenarios: climate change and planned developments. At the coast-wide scale, climate change drove the largest change in cumulative effects with both widespread impacts and high vulnerability scores. Where the impacts of planned developments occur, planned industrial and pipeline activities had high cumulative effects, but the footprint of these effects was comparatively localized. Nearshore habitats were at greatest risk from planned industrial and pipeline activities; in particular, the impacts of planned pipelines on rocky intertidal habitats were predicted to cause the highest change in cumulative effects. This method of incorporating planned industrial development in cumulative effects mapping allows explicit comparison of different scenarios with the potential to be used in environmental impact assessments at various scales. Its use allows resource managers to consider cumulative effect hotspots when making decisions regarding industrial developments and avoid unacceptable cumulative effects. Management needs to consider both global and local stressors in managing marine ecosystems for the protection of biodiversity and the provisioning of ecosystem services.

The rapidly progressing field of cumulative effects mapping is highly dependent on data quality and quantity. Availability of spatial data on the location of human activities on or affecting the ocean has substantially improved our understanding of potential cumulative effects. However, datasets for some activities remain poor and increased access to current, high resolution data are needed. Here we present an updated analysis of potential cumulative effects in Canada’s Pacific marine waters. New, updated datasets and methodological improvements over the previous analysis were completed, including a new index for land-based effects on marine habitats, updated habitat classes and a modified treatment of vulnerability scores. The results show increased potential cumulative effects for the region. Fishing remains the biggest overall impact amongst marine activities, while land-based activities have the highest impact per unit area in affected ocean areas. Intertidal areas were the most affected habitat per unit area, while pelagic habitats had the highest total cumulative effect score. Regular updates of cumulative effects assessments will make them more useful for management, but these require regularly updated, high resolution datasets across all activity types, and automated, well-documented procedures to make them accessible to managers and policy-makers.