鄱阳湖南昌湖区典型断面水质变化特征及污染源解析研究——以伍湖分场国控断面为例

Characteristics of Water Quality Change and Analysis of Pollution Sources in Poyang Lake——A Case Study of the Wuhufenchang State-controlled Section

伍湖分场断面是鄱阳湖南昌湖区五大国控断面之一。针对2020年以来鄱阳湖流域总磷(TP)枯水期浓度偏高的问题,以伍湖分场断面为例,根据逐月监测和加密监测数据,分析断面水质近况。结果表明,断面TP浓度突增月份出现在12月,2021年断面枯水期TP的平均浓度相较于2020年有所增加。根据2021年11月至2022年8月的加密监测结果,显示断面的水质问题仍然是枯水期的TP浓度较高。TP的主要排放源头较为分散,主要为农业种植源(48.25%),其次是内源释放(18.05%)、生活源(17.04%)及干湿沉降(13.55%)。TP入湖量占比最大的是联圩镇,占汇水区域入湖总量的41.59%,其次则是成新农场与恒湖垦殖场,排放量总和占据近一半。TP排放占比最高的成新农场和联圩镇是治理工作的重点区域,其次是以农业种植业为主的恒湖垦殖场也需要相应的治理措施。据此提出相应水质提升(稳定)措施,以期断面水质在“十四五”期间稳定达到国控考核,为伍湖分场断面乃至鄱阳湖流域的水环境质量改善提供技术支持。

Wuhufenchang state-controlled section is one of the five major sections in the Nanchang area of Poyang Lake.In view of the high concentration of total phosphorus(TP)in the dry season in the Poyang Lake Basin since 2020,this study takes Wuhufenchang state-controlled section as a case study to analyze the current water quality in the section based on monthly monitoring and inten-sive monitoring data.The monthly monitoring results showed that the spike in TP concentration ap-peared in December,and the average TP concentration in 2021 was higher than that in 2020.Ac-cording to the intensive monitoring results from November 2021 to August 2022,the problem of wa-ter quality in the section is still the high TP concentration in the dry season.The main sources of TP discharge are scattered,mainly agricultural planting sources(48.25%),followed by endogenous release(18.05%),living sources(17.04%),dry and wet deposition(13.55%).The large con-tributor to TP discharge amount is Lianwei Town,accounting for 41.59%of the total discharge a-mount in the catchment area,followed by Chengxin Farm and Henghu Reclamation Farm,with their integrated emissions accounting for nearly half of the total.Chengxin Farm and Lianwei Town,with the highest TP discharge,are the key areas for management,followed by Henghu Reclamation Farm,which mainly focuses on agricultural planting,and also need corresponding governance meas-ures.Based on this,this study proposes corresponding measures to improve(stabilize)water quali-ty,so as to ensure that the water quality of the section can meet the national control assessment dur-ing the“14th Five Year Plan”period,and provide technical support for the improvement of water environment quality in the section of Wuhufenchang section and even in the Poyang Lake basin.