湖州合溪新港污染物入湖通量估算与分析

根据2021年5月—2022年4月合溪新港河流水量、水质(TN和TP)的同步监测数据，利用通量模型核算了合溪新港污染物(TN和TP)通量。通过测算合溪新港TN、TP通量与断面降雨强度、水质的响应关系，分析了该区域的污染类型及特点，为后期水质污染调查及通量研究提供了新思路。结果表明：合溪新港流量与降雨量存在明显相关关系，在强降雨期(7—8月)水体流量最高，占监测周期总流量的57.77%;少雨期则流量最低，且会出现湖水倒灌现象(11—12月)。通过分析合溪新港TN、TP通量与流量、水质的相关关系，确定了该流域污染类型为点源污染及农业面源污染共存的混合型污染，且在高强度降雨时污染物负荷量较大。综上，可针对农业面源污染对该流域治理提出相关对策，建立农业面源污染防治体系，以有效降低TN和TP污染物的入湖通量，减少太湖TN和TP污染物负荷量。

Estimation and Analysis of Pollutant Influx into the Hexi Xingang River of Huzhou

The pollutant flux of Total Nitrogen (TN) and Total Phosphorus (TP) in the Hexi Xingang River from May 2021 to April 2022 was accounted by using flux model based on the simultaneous monitoring data of water flow and water quality.The pollution type and characteristic in the Hexi watershed was analyzed by deducing the response relationship between pollutant flux (TN,TP) and rainfall intensity as well as water quality,which provided a new vision for the investigation of polluted water condition and the flux study.Results showed that there was an obvious correlation between the Hexi discharge and rainfall,which presented the highest discharge in the heavy rainfall period (July-August),accounting for 57.77% of the total discharge,while the discharge was the lowest in the low rainfall period.The flow backwards of Taihu Lake water occurred in the dry period (November-December).A mixed type of point source pollution and agricultural non-point source pollution in the Hexi watershed was deduced through the correlation between TN,TP fluxes and flow and water quality.And the pollutant load was larger during higher intensity rainfall.In conclusion,relevant countermeasures could be put forward for agricultural non-point source pollution in this basin,and the prevention and control system of agricultural non-point source pollution could be established,which might effectively reduce the flux of TN and TP pollutants into Taihu Lake and reduce the load of TN and TP pollutants in Taihu Lake.