The Pressure Evaluation Of Agricultural Pollution In Taihu Lake Basin

The water environment quality presents a serious deterioration in the Taihu Lake and itsbasin, the agricultural pollution is one of the main reasons of water environmentaldeterioration. The agricultural pollutants mainly come from the productive process of planting,livestock and poultry breeding and aquaculture. In order to analyze the influence of theagricultural pollutant on the water environment quantitatively and explore the ways abouthow to reduce the agricultural pollutants. Hope that the agriculture in Taihu Lake Basin canrealize the sustainable development and the water resource can realize the sustainable use,besides, hope that this paper can do some contribution to the water management.This paper developes an agricultural pollution model which calculates the pressure indiceof agricultural pollution based on the cultivation of plants and the breeding of livestock,poultry and aquaculture, evaluating the influence of the agricultural pollutants in ChangzhouCity, Yixing City and Huzhou City. The results shows that：(1) Nitrogen and phosphorus pollutants largely contributed to water pollution withpollutions pressure indice value greater than one. Spatial distributions of agricultural pollutionpressure indics differed not only with different cultivation and breeding practices, but alsowith region.(2) The amount of COD pollutant take up the most proportion in the cultivation ofplants-pollutant, the proportion is about 52%, the second is the amount of TN pollutant, theproportion is about 45%, the third is the amount of TP pollutant, the proportion is about 3%.(3) The amount of COD pollutant take up the most proportion in the breeding oflivestock-pollutant, the proportion is about 91%, the second is the amount of TN pollutant, theproportion is about 8%, the third is the amount of TP pollutant, the proportion is about 1%.(4) The amount of COD pollutant take up the most proportion in the aquaculturalpollutant, the proportion is about 80%, the second is the amount of TN pollutant, theproportion is about 18%, the third is the amount of TP pollutant, the proportion is about 2%.(5) Thinking about the resources of the COD, though the results calculated in this paper, we can conclude that the aquaculture and the livestock and poultry breeding are the maincontributors, the proportion of the two is more than 80%.(6) Thinking about the resources of the TN, though the results calculated in this paper,we can conclude that planting is the main contributor, the proportion is more than 50%(7) Thinking about the resources of the TP, though the results calculated in this paper, wecan conclude that the aquaculture is the main contributor, the proportion is more than 50%.In conclusion, in order to reduce the COD pollutants, we should take measures abouthow to deal with the livestock and poultry breeding and aquaculture; in order to reduce theTN pollutants, we should take measures about how to deal with the planting; in order toreduce the TP pollutants, we should take measures about how to deal with the aquaculture.