VULNERABILITY OF COASTAL ENVIRONMENTS TO OIL SPILL IMPACTS

TLDR

Coastal habitats can retain oil for extended periods, with some salt marshes predicted to have residence times exceeding ten years. The authors developed a 1–10 vulnerability index for coastal environments, weighting oil residence time and initial biological impacts. Rocky headlands and wave‑cut platforms score low on the index, sandy beaches score intermediate, while sheltered rocky coasts, salt marshes, and mangroves score high, indicating they are most vulnerable to oil spills.

Abstract

On the basis of field studies of five major oil spills and a review of the literature, major coastal environments have been classified on a scale of 1 to 10 in terms of potential vulnerability to oil spill damage. The scale emphasizes oil residence time, with consideration of initial biological impacts. Exposed rocky headlands and wave-cut platforms (1 and 2 on the Vulnerability Index) are generally least affected by an oil spill. Coarse-grained sandy and gravel beaches, which are subject to oil penetration and burial, are assigned intermediate index values of 4 to 7. Sheltered environments such as sheltered rocky coasts, salt marshes, and mangroves (index values of 8 to 10) are the environments most likely to be adversely affected by oil spills. For example, residence times of over 10 years are predicted for some salt marsh areas.