Water Quality Assessment of Zhaitou River in Maoming City Based on Mathematical Model Analysis
This study aims to provide a novel combined of inspection method to realize the water quality characteristics of rivers entering the sea in Maoming City, thereby taking the Zhaitou River as the research area, using the water quality monitoring data from June to December 2021, and four influencing factors CODMn, NH3-N, DO and TN are selected. Then, the water quality is evaluated by using Fuzzy comprehensive evaluation method and Grey prediction GM (1,1) model, and the water quality in the next three phases is predicted. The results show that the Fuzzy comprehensive analysis indicated that the overall water quality from June to December 2021 belongs to class III water, especially the water quality in July and December is the worst, which are class IV and class V water respectively. According to the prediction of the Grey prediction model, the accuracy of the posterior error ratio is 0.114 at the lowest and 0.369 at the highest. Through the accuracy test, the relative residual of the four factors is within 20%, and the model fitting effect is good. The simulation prediction results show that the predicted values of the other three factors are rising except NH3-N.
Keywords: Water quality assessment; Fuzzy comprehensive evaluation method; Grey prediction GM (1,1) model