An exposure score to assess anthropogenic footprint on coastal ecosystems at the local scale

Abstract

Anthropogenic influence is a widespread phenomenon affecting coastal ecosystems, the majority of which bears various cooccurring human activities. The exposure and vulnerability of ecological communities and habitats to multiple human activities are promising indicators of the state of coastal benthic ecosystem worldwide. In this study, we developed an anthropogenic exposure score using a particle diffusion model and fishing events data for seven human activities: mussel aquaculture, sediment dredging, runoff from city and industries, sewer discharge, commercial shipping, artificial structures and coastal fisheries. This score was applied to ecosystems in the region of Sept-Îles (Québec, Canada), a major industrial harbour area in the Gulf of St. Lawrence and the fifth Canadian commercial harbour. Cumulative score was low to moderate throughout the studied area, with some localized regions showing higher values (‘hotspots’). Using exposure scores as predictors in a regression model, a significant portion of the benthic community structure was explained, giving evidence to ecological links between exposure and species vulnerability to human activities. By using these scores in environmental assessments, we hope to increase their efficiency for local stakeholders, even more in ecosystems where available ecological data is limited and to further pave the way towards holistic and integrated ecological management.