关键词: 面源污染, 输出系数法, 污染负荷分析, 丹江口库区

Abstract: In recent decades, the situation of non-point source pollution in the water sources area of the Middle Route Project of South-to-North Water Diversion is increasingly focused. This study selects representative monitoring sections in Danjiangkou reservoir area to analyze the water quality and eutrophication as well as the situation of non-point source pollution in the water source area through output coefficient method. The analysis concludes that water quality in Danjiangkou reservoir area is basically good, but the total nitrogen exceed the standard; the eutrophication degree is not high at present, still at medium level of eutrophication degree; in 2014, the output of total nitrogen (TN) and total phosphorus (TN) in water source area were 13.53×104 t and 0.63×104 t, livestock industry and rural life contributed the highest to TN and TP; in the view of administrative divisions, the city of Shiyan was the highest in annual output of TN, the city of Hanzhong was the highest in annual output of TP and the city of Nanyang was the highest in pollution load per unit area; in the view of different geographic areas, the pollution load in plain and hilly area was highest, the pollution load intensity decreased with the rise of altitude. Based on the calculation of non-point source pollution, we can find out the flux and distribution characteristics of non-point source pollution to provide technical support for water quality protection and management.

Key words: non-point source pollution, output coefficient method, pollution load estimation, Danjiangkou reservoir area