Coastal protection by coral reefs: A framework for spatial assessment and economic valuation

Coral reefs are highly productive ecosystems that provide various valuable ecosystem services. The worldwide decline in coral cover and the expected increase of hurricane frequencies and sea level rise have raised the attention to one ecosystem service in particular. This is the coastal protection service of coral reefs, which is based on the principle that reefs dissipate wave energy by wave breaking or friction by reef structures and thus protecting coastal assets against floods. There have been several regional and local studies on economic value of coastal protection of coral reefs, each of which adopted simplifying assumptions on critical parameters such as reef and wave characteristics, climate and coastal development. The main objective of this paper is to develop a comprehensive analytical framework for spatial assessment and valuation of coastal protection services by coral reefs. The analytical framework is tested in the context of the United States Virgin Islands. The study is innovative because several aspects are explicitly integrated in the conceptual framework such as flood insurance rate maps (FIRMs), reef typology, a wave model and the depth-damage model. The coastal protection value of coral reef ecosystems in the USVI is estimated at an annual value of 1.2 M USD attributed to friction of coral structures.