国控沙段断面“一点一策”现状及治理对策研究

Study on Present Situation of“Differentiated Control Measures for Specific Pollutants”and Control Measures for State-controlled Shaduan Section

为科学提出水环境治理对策,分析国控沙段断面及流域范围内其他断面2015~2020年水质情况,以乡镇为控制单元,计算各单元内化学需氧量(COD)、氨氮(NH_(3)-N)和总磷(TP)三种污染物入河占比情况,摸清当前沙段断面流域范围内水生态环境现状。结果表明:“十三五”期间,国控沙段断面水质不稳定达到Ⅱ类考核目标,其主要超标因子为总磷,上游百步交接断面水质对沙段有较大影响。在污染物入河量占比中,总磷农业面源贡献比重最大,各控制单元中平桥镇和白鹤镇占比居前两位,分别为8.87%和7.13%。总磷贡献次重为生活源,赤城街道占比居首位,为7.08%。研究成果可为稳定沙段断面水质、改善河流水生态环境,提出针对性治理对策提供重要参考依据。

In order to put forward measures for control of water environment in a scientific way,the water quality of state-controlled Shaduan Section and other sections in the basin from 2015 to 2020 was analyzed.With towns as control units,the proportion of three pollutants which included chemical oxygen demand,ammonia nitrogen and total phosphorus in each unit were calculated,and the current situation of water ecological environment in the basin of the Shaduan Section was understood.The results showed that the water quality of state-controlled Shaduan Section was unstable and reached the Class II assessment target during the 13th Five-year Plan period,and the main over-standard component was total phosphorus.The water quality of upstream Baibu intersection had a great impact on the Shaduan Section.Total phosphorus from agricultural non-point sources contributed the most to the amount of pollutants entering the river,with Pingqiao Town and Baihe Town ranking top two among the control units,which accounted for 8.87%and 7.13%,respectively.Domestic sources contributed the second most to total phosphorus,and Chicheng Town took the first place in this regard,accounting for 7.08%.The research results provide important reference for stabilizing the water quality of the Shaduan Section,improving the ecological environment of rivers and proposing targeted control strategies.