Application of Optimized Fuzzy Comprehensive Evaluation Method in Water Quality Evaluation of Xiamen Bay

Based on the water quality monitoring data in the spring, summer and autumn of 2018 in Xiamen Bay, this study used the fuzzy comprehensive evaluation method to comprehensively evaluate the water quality. The results showed that the Western sea area of Xiamen, Tong'an Bay and Jiulong River estuary were seriously polluted areas, which were class Ⅳ water bodies; the water quality of southern sea area, eastern sea area and Dadeng sea area was in good condition, mainly class Ⅰ water body; DIN and DIP were the main pollutants affecting the water quality of Xiamen Bay; using the area ratio method on the basis of the results obtained by the fuzzy comprehensive evaluation method, the results showed that in 2018, Xiamen Bay as a whole was in Class Ⅲ water body condition, and the water quality needed to be further improved.