Abstract

In recent decades, the growing demand for energy has significantly increased the volume of marine transportation and exploration, which raises the risk of marine oil spills that endanger coastal and marine ecosystems. These ecosystems provide crucial services for human well-being. The main objective of this study is to identify areas most sensitive to oil spills in the Gulf of St. Lawrence, considering the value of ecosystem services. To achieve this, four groups of ecosystem services were considered: cultural, provisioning, supporting, and regulating services. For cultural services, tourism data on marine conservation areas, historic sites, and national parks were analyzed. Provisioning services were evaluated by considering commercial fisheries and aquaculture activities. Supporting services focused on biodiversity maintenance, including seabirds and marine mammals, while regulating services were assessed by accounting for carbon sequestration and natural waste processing. The socio-economic sensitivity map was created based on the values of provisioning and cultural ecosystem services, and the biological sensitivity map was developed using regulating and supporting services. To complete the sensitivity analysis, a physical sensitivity map was also created, considering shoreline characteristics such as tidal range, wave height, slope, and cleanup cost based on the shoreline classification. The final integrated sensitivity map for the Gulf of St Lawrence was generated by combining the physical, socio-economic and biological layers. The highest sensitivity was observed along the shorelines of the Gulf, within the Estuary, and near the Anticosti Island. This study provides an integrated plan for oil spills, enabling decision makers to prioritize zones for protection before an oil spill and to optimize their cleanup efforts during an incident.