Assessment of ecosystem health in the Bohai Sea and countermeasures study

Based on the index system of 22 indicators including water environment, sedimentary environment, and ecosystem obtained from the investigation data of several voyages in the Bohai Sea during 2014 to 2016, the ecosystem health in the Bohai Sea was assessed using the Analytic Hierarchy Process(AHP)method. The results showed the CEI value of marine ecosystem health is 0.643 and its health level is medium, which indicates the ecosystem health around the Bohai Sea is in a sub-health state. The maritime areas with poor ecosystem performance were located mainly in Laizhou Bay, Bohai Bay, and its adjacent area of the Yellow River Delta. The ecosystem health of offshore waters and high-seas area nearby Tangshan, Qinhuangdao, and Huludao were generally at an intermediate level. The central study area along with Bohai Straits displayed relatively better health state. Be familiar with the assessment result, this paper performed analysis on the health stress factors in Laizhou Bay and Bohai Bay, and obtained land-based input and reclamation results. Based on these stress factors, countermeasures are studied to provide decision support in the management of the Bohai Sea