Sensitivity mapping of particular sensitive areas

Abstract

The Wadden Sea, a region of tidal flats and salt marshes extending at the North Sea coast of the Netherlands, Germany and Denmark, is of enormous value as a cleansing site for North Sea water, as a nursery for young fish, and as a feeding ground for many bird species. The region is especially endangered by oil spills due to the proximity of important shipping routes and harbours. Sheltered tidal flats, salt marshes and adjacent estuaries belong to the cost types most sensitive to oil pollution. As it is not possible to protect the entire German North Sea coast at equal levels, oil spill contingency planning requires a more detailed classification. For this reason, based on the results of field and laboratory studies, individual soft bottom habitats and communities (halophytes, macrofauna, meiofauna, microphytobenthos) as well as waterfowl and estuarine biotop types were evaluated and classified according to their vulnerability to oil pollution. The use of a synchronously developed data processing system including GIS allows the application of metadata on different aggregation levels: specific information can serve scientific purposes; information on spatiotemporal vulnerability to oil pollution is highly condensed to four classes to support the practicability of preventive, remedial and response measures. The resulting sensitivity maps are part of the German contingency plan. The basic concept may hold as a useful strategy to differenciate the sensitivity of similar coastal areas with high ecological vulnerability as a whole.