Analysis on Water Quality and Eutrophication State of Honghu Lake, China: A Case Study of Vegetation Restoring Model District

The vegetation restoring model district lies in the southeast of Honghu Lake which is interlinked with the Yangtze River through the river course. Based on the field investigation and test, this paper applies the fuzzy mathematical principle and uses five parameters to assess the water quality of the model district. Inferring from the fuzzy concept, which is more objective comparing with other assessment measures, the synthetic assessment result calculated out is that the level of water quality in the study region of Honghu Lake is IV. Lake nutritional status of the composite index is used to appraise its nutritional status and the result is Mesotropher but it has the tendency to Eutropher. Phosphorus element is the main limiting factor. The result indicates that the water quality of the study region changes better slightly and the eutrophication condition is to become aggravated. Therefore, the wetland ecological engineering project in the model district is able to improve water environment of Honghu Lake.