基于SWAT的泗河流域非点源污染物时空分布特征

Temporal and spatial distribution of non-point source pollutants in Sihe River Basin based on SWAT

利用水土评价工具(soil and water assessment tool,SWAT)构建分布式水文模型,模拟流域内主要非点源污染物输出量(总氮输出质量mTN、总磷输出质量mTP),结合Arcgis分析了mTN、mTP时空分布特征,并识别了关键源区。结果表明,2014-2018年流域的年均mTN、mTP为1973.08、134.41 t,年内变化具有明显季节性特征,汛期平均总氮、总磷输出负荷分别占全年的73.5%、78%,年均mTN、mTP集中在流域坡耕地较多的东北部、东南部,以及流域内种植水稻、玉米较多并在汛期施肥的中部。研究结果可为有效制定泗河流域非点源污染物的消减措施提供技术支撑。

In order to investigate the temporal and spatial distribution characteristics of main non-point source pollutants in Sihe River Basin,a distributed hydrological model of soil and water assessment tool(SWAT)was constructed to simulate the output of two main non-point source pollutants(total nitrogen output quality mTN and total phosphorus output quality mTP)in the basin.Combined with Arcgis,the temporal and spatial distribution characteristics of the mTN and mTP were analyzed to identify the critical areas of the mTN and mTP.The results showed that the average annual mTN and mTP from 2014 to 2018 was 1973.08 t and 134.41 t,while their output in flood season accounted for 73.5%and 78%of the whole year,respectively.This illustrated temporal distribution had obvious seasonal characteristics.The sub-area with high intensity of the mTN and mTP were concentrated in the northeast and southeast of the Sihe River Basin with more slope farmland.The middle of the basin with more rice and corn also showed a high loss of the mTN and mTP in the flood season.The results could provide technical support for the management of effectively reduction of non-point source pollutants in Sihe River Basin.