石头口门水库双阳河流域农业非点源污染发生潜力评价

Evaluation on Agricultural Non-point Source Pollution Potential in Shuangyang River Catchment of Shitoukoumen Reservoir

以资料收集、实地调查结合GIS技术为主要手段,采用农业非点源污染发生潜力(APPI)模型,对石头口门水库双阳河流域9个行政区的农业非点源污染发生潜力进行预测和评价,并通过对该流域的农业非点源污染负荷量的估算进行验证。结果表明,流域9个行政区中农业非点源污染发生潜力最大的是平湖区,齐家和太平次之,结果与污染负荷量的估算结果基本一致。流域内化肥氮磷排放量为9512t·a-1,畜禽氮磷排放量为30731t·a-1,居民氮磷排放量为1645t·a-1,可见畜禽氮磷排放造成的非点源污染最为严重,占整个非点源污染负荷的73%,需作为优先控制的对象引起足够的重视。

The primary issue of effectively controlling and managing agricultural non-point source （NPS） pollution and improving the quality of water is how to identify critical areas and variety of pollutants source. Based on the field experiments, collecting relevant environmental data and analyzing by geographical information system technique, the model of agricultural non-point source pollution potential index （APPI） was applied in nine villages or towns of Shuangyang River catchments in Shitoukoumen Reservoir watershed. The factors of the model include runoff, soil erosion, fertilizer, human and animal loading. With the aid of GIS, the areas of high APPI value are identified as high risk or relatively high risk of agricultural NPS pollution and should be given a particular attention. The result shows that the critical area identified for NPS control was Pinghu, Qijia and Taiping where the APPI is the top three. The nitrogen and phosphorus pollution load was investigated and calculated for the source apportionment analysis and validation of APPI, which is consistent with the identified results basically. The load distribution of the agricultural NPS pollution in Shuangyang catchments is that the sum of the nitrogen and phosphorus pollution discharged from chemical fertilizers is about 9 512 t·a^-1, from the livestock is 30 731 t·a^-1, from the dwellers is about 1 645 t·a^-1, The nitrogen and phosphorus pollution from livestock occupies 73% of all kinds of pollution, indicating that the nitrogen and phosphorus pollution from livestock was one of the key factors, which should be paid more attention as priority controlling target.