Application of Improved Fuzzy Comprehensive Evaluation Method in Eutrophication Assessment for Tributary Bays in the Three Gorges Reservoir, China.

Since the operation of the Three Gorges Reservoir, its tributaries have been eutrophic and flooded many times, the prompt and accurate eutrophication assessment is the foundation of water environmental management for this area. To address the problems existing in the fuzzy comprehensive evaluation, a novel method is proposed to adjust the indicator weight by using the analytic hierarchy process-entropy weight method, improve the fuzzy operation method, and take the weighted average as the basis of comprehensive evaluation. Through this method, the information of each indicator can be comprehensively used, and the subjectivity and blindness of evaluation can be effectively reduced. Then the eutrophication status of Hanfeng Lake is analyzed by it, and compare the results with that of conventional methods. The results show that Hanfeng lake is greatly affected by TN and TP, and it is generally in mesotrophic to mildly eutrophication. Eutrophication degree is: Nanhe River > Donghe River > Regulating dam, so the control measures should be strengthened in Nanhe area. Combined with the water pollution control measures proposed in this paper, it can provide guidance for the monitoring and treatment of eutrophication in the Three Gorges Reservoir area and ensure the safety of the water environment.