四川凯江流域农村非点源污染特征分析

为探讨凯江流域农村非点源污染状况，防止区域非点源污染进一步加剧，本文选取农村生活源、畜禽养殖源、农田径流源3大污染源，以2015年为基准年，利用排污系数法估算了COD、NH₃-N和TP的污染入河负荷。结果表明，2015年凯江流域农村非点源污染入河COD、NH₃-N和TP总量分别为4 906.71、1 074.02、203.50 t；农村生活源对COD和NH₃-N的入河贡献率最大，畜禽养殖源对TP的入河贡献率最大；凯江流域入河污染物主要分布在中江县、三台县和罗江县，COD、NH₃-N和TP入河量之和分别占凯江流域该类污染物入河总量的84.52%、84.28%和89.72%，其中中江县的污染负荷入河量最大。研究表明，中江县、三台县和罗江县是凯江流域农村非点源污染产生的关键区域，需重点关注。

Characteristics of rural non-point source pollution in Kaijiang Basin of Sichuan Province

In order to investigate the Kaijiang River Basin rural non-point source pollution and prevent non-point pollution aggravated, this article choosed rural life source, livestock and poultry breeding source and farmland runoff source of pollution to estimate their load of chemical oxygen demand(COD), ammonia nitrogen(NH₃-N) and total phosphorus(TP) into the river in 2015 by using the blowdown coefficient method. The results showed that the total amount of COD, NH₃-N and TP was 4 906.71, 1 074.02 t and 203.50 t. The contribution of rural life sources to COD and NH₃-N was the largest, and the livestock and poultry breeding sources contributed most to TP contribution to the river. The pollutants in the river were mainly distributed in Zhongjiang County, Santai County and Luojiang County, the total amount of COD, NH₃-N and TP respectively accounted for 84.52%, 84.28% and 89.72% of the total amount of pollutants to the river. Among them, Zhongjiang County pollution load into the river was the largest.