天津市非点源污染现状研究

The Investigation of Non-point Source (NPS) Pollution in Tianjin

随着天津市点源污染近年来得到进一步治理,非点源污染在水体污染中所占的比重越来越大。天津市非点源污染影响主要来自5个方面:畜禽养殖、农田地表径流、农村地表径流、水产养殖换水及城市地表径流,通过分析各方面的排放特性,得到了天津市非点源污染负荷:CODCr为204703.4t·a-1,BOD5为54100.8t·a-1,NH3-N为9881.3t·a-1。文章从排污系数对比、非点源污染构成、非点源污染负荷密度3个方面分别对非点源污染负荷进行了分析,得出了以下结论:水产养殖的排污系数最高;农田径流、畜禽养殖产生的污染负荷最大;武清区、蓟县和宝坻区污染最为严重。最后针对5种不同的类型提出了控制对策。

As the control of point source pollution in Tianjin, the NPS pollution has taken more weight. There are five main aspects that affect the NPS pollution, namely poultry cultivation, farmland runoff, countryside runoff, aquicuhure waste water and urban land runoff. By the research of the discharge characteristic of each aspect, the author gets the load of NPS pollution in Tianjin： CODcr is 204 703.4 t·a^-1, BOD5 is 54 100.8 t·a^-1, NH3-N is 9 881.3 t·a^-1. The paper analyzes the NPS load from the contrast of different discharge coefficient, the construction of the NPS pollution, and the NPS load density, and gets conclusions that： the aquicuhure waste water has the highest discharge coefficient; the farmland runoff and the poultry cultivation produce more NPS load; the NPS pollution in Wuqing district, Ji county and Baodi district are worst. At last, the author proposes the control measures to each aspect.