Calculation and analysis of water pollution load in Yanqi River Basin

Based on field investigation and monitoring data,this paper studied the source of water pollu tion and river pollution load with a water pollution load evaluating model in the Yanqi River Basin.The pa per also established a water quality model to analyze water environmental capacity that will be one of the constraint conditions of intensity and scale for water environment carrying capacity under all kinds of con trol methods of water pollution source.The results show that:the water pollution load of catering trade is 2%,that of natural village is 12%,that of breeding of fish field is 86%,which is the main water pollu tion source.This basin system is in the overload state since the water pollution load is much greater than water environmental capacity.It is necessary either to decrease water pollution emission in fish field or to increase the rate of wastewater treatment that will reduce the river pollution load.The various ecological res toration methods should be taken to improve the water environment carrying capacity and maintain the sus tainable development of society and economy for the serious pollution reaches of the Yanqi River Basin.