Evaluation for the ecological quality status of coastal waters in East China Sea using fuzzy integrated assessment method

This research presented an evaluation for the ecological quality status (EcoQS) of three semi-enclosed coastal areas using fuzzy integrated assessment method (FIAM). With this method, the hierarchy structure was clarified by an index system of 11 indicators selected from biotic elements and physicochemical elements, and the weight vector of index system was calculated with Delphi-Analytic Hierarchy Process (AHP) procedure. Then, the FIAM was used to achieve an EcoQS assessment. As a result of assessment, most of the sampling stations demonstrated a clear gradient in EcoQS, ranging from high to poor status. Among the four statuses, high and good, owning a ratio of 55.9% and 26.5%, respectively, were two dominant statuses for three bays, especially for Sansha Bay and Luoyuan Bay. The assessment results were found consistent with the pressure information and parameters obtained at most stations. In addition, the sources of uncertainty in classification of EcoQS were also discussed.

► A fuzzy integrated EcoQS assessment method was proposed for coastal waters. ► A clear gradient of EcoQS was observed over the whole range of studied stations. ► The assessment results were greatly consistent with the anthropogenic pressure. ► This method was more suitable for areas with lower anthropogenic pressures. ► The method proposed could detect out the risk priority substances in water.