辽河源头区流域农业非点源污染负荷估算

近年来,非点源污染已成为我国水体污染的主要来源,其中又以农业非点源贡献最大。为探究辽河源头区流域农业非点源污染程度,运用排污系数法估算1999-2009年流域非点源污染负荷进行估算,对COD、TN、TP和氨氮的污染负荷变化趋势进行分析,应用等标污染负荷法对流域农业非点源污染状态进行评价。结果表明:1999-2009年辽河源头区流域农业非点源污染COD,TN,TP,NH3-N平均入河总量分别为35 899.67,10 402.40,1 258.56,4 306.22t/a。从不同污染物看,TN是辽河源头区流域面源污染的主要污染物,占污染物比重的47.21%。从不同污染源分析,畜禽养殖的污染负荷比为70.56%,远远超过另外三种类型的非点源污染负荷的总和,畜禽养殖污染是辽河流域非点源污染的主要来源,农村生活源的污染负荷比为19.33%,高于种植业及水产养殖业。从流域不同地区看,梨树、公主岭、东辽、双辽4市县对流域污染贡献较大,是辽河源头区流域的主要污染区域。

Load estimation of agricultural non point source pollution in source area of Liaohe River

Non-point source pollution has became a major source of water body pollution in China in recent years, in which the largest contribution is agricultural non-point source pollution. In order to explore agricul- tural non-point source pollution levels of the source area of Liaohe River, the paper used pollutant emission coefficient to estimate non-point source pollution load in the area from 1999 to 2009and analyze the variation trend of COD, TN, TP and ammonium nitrogen pollution load. The equivalent standard pollution load meth- od was applied to evaluate agricultural non-point source pollution status. The results showed that the total export of chemical oxygen demand （ COD）, total nitrogen （ TN ）, total phosphorus （TP） and ammonium ni- trogen（NH3-N） were 35899.67, 10402.40, 1258.56 and 4306.22 tons per year from 1999 to 2009 in the source area of Liaohe River watershed, respectively. Among all different pollutants, TN is the major pollu- tants of non-point source pollution in the source area of Liaohe River watershed, which accounts for 47.21% of all pollutants. Among all different sources, the pollution load ratio of livestock and poultry breeding is 70.56% witch is far more than the sum of the other three types of non-point source pollution load . Livestock pollution is the main source of non-point source pollution in Liaohe River basin. The ratio of rural life source pollution load is 19.33% which is higher than the farming and aquaculture. By compari- son of different areas, the non-point source pollution load of Lishu, Gongzhuling, Dongliao and Shuangliao is greater than that of other areas and the four cities/counties are the major pollution areas.