南汀河大文断面水质变化及原因研究

Analysis of Water Quality Change and Its Cause in Dawen Section of Nanting River

基于单因子评价方法研究2020年-2022年间大文监测断面水质状况,结果表明,大文水质总体趋于好转,水质超标指标已经由2020年的氨氮、总磷、化学需氧量、五日生化需氧量4个指标,减少为2022年的化学需氧量、五日生化需氧量2个超标指标;超标次数也由7次减少为4次。通过文章研究,城镇生活污染、河道营养化、农业面源污染是大文水质污染的三个主要原因。文章建议对大文断面上游加强农业面源管控,完善主城区污水管网等措施,推进河道生态修复,加大南汀河流域周边湿地保护与修复力度,提高水体自净能力,推进南汀河流域可持续发展。

The water quality of Dawen monitoring section from 2020 to 2022 was studied based on the single factor evaluation method.The results showed that the water quality of Dawen tended to improve overall,and the water quality exceeding the standard indicators had been reduced from the four indicators of ammonia nitrogen,total phosphorus,chemical oxygen demand and five-day biochemical oxygen demand in 2020 to two exceeding the standard of chemical oxygen demand and five-day biochemical oxygen demand in 2022.The number of exceedances has also been reduced from 7 to 4.According to this study,urban pollution,river nutrition,and agricultural non-point source pollution are the three main causes of water pollution in Dawen.This paper suggests that measures such as strengthening the control of agricultural non-point sources in the upstream of the Dawen section,improving the sewage pipe network in the main urban area,promoting the ecological restoration of the river,increasing the protection and restoration of wetlands around the Nanting River Basin,improving the self-purification capacity of water bodies,and promoting the sustainable development of the Nanting River Basin.