蒙溪河流域水环境污染及演变趋势研究

Study on Water Environmental Pollution and Evolution Trend in Mengxi River Watershed

研究采用Arc GIS确定蒙溪河流域研究范围,在此基础上进行水环境污染现状及演变趋势分析、污染源调查和水环境容量计算。结果表明:蒙溪河流域水质超标情况较严重,主要超标因子为:COD、TN和TP,COD和TP的压力主要集中在平水期,TN压力主要集中在枯水期;污染源汇入主要集中在4#-9#点位之间。蒙溪河流域污染物入河量从大到小依次为:农业面源、城镇生活污水、农村生活污水、规模化畜禽养殖、畜禽散养和底泥污染。蒙溪河流域达标需削减污染物量:COD为217.755t/a,NH_(3)-N为24.683t/a,TN为75.710t/a,TP为10.774t/a。

In this study,Arc GIS was used to determine the research scope of the Mengxi river basin,and on this basis,the status and evolution trend analysis of water environmental pollution,the investigation of pollution sources and the calculation of water environmental capacity were carried out.The results showed that the water quality in mengxi river basin exceeded the standard seriously,and the main factors were COD,TN and TP.The pressure of COD and TP mainly concentrated in the plain period,while the pressure of TN mainly concentrated in the dry period.The pollution sources are mainly concentrated between the point 4#-9#.The amount of pollutants into the Mengxi river basin from large to small is:agricultural non-point source,urban sewage,rural sewage,large-scale livestock and poultry breeding,livestock and poultry free-range and sediment pollution.The amount of pollutants needed to be reduced to meet the standards in Mengxi river basin:COD is 217.755 t/a,NH3-N is24.683 t/a,TN is 75.710 t/a,and TP is 10.774 t/a.