重庆市盘溪河流域典型降雨过程TSS污染负荷模拟

Modelling of Non-point Source TSS Pollution Load during Rainfall Events in Panxi River Basin in Chongqing

随着城市化进程的加速,城市面源污染问题日益突出。作为污染治理的重要依据,城市面源污染负荷估算及来源解析受到广泛重视。针对重庆市盘溪河流域,建立了典型降雨过程的面源污染负荷模型,计算了降雨径流过程中TSS浓度,并对盘溪河流域的各子流域面源负荷产生量进行了计算。结果表明:建立的模型可以较好地模拟降雨产汇污过程,尤其是对降雨初期的冲刷过程模拟精度较高。在列举的两次降雨事件中,均存在明显的初始冲刷效应,在前30%的径流中,两次降雨冲刷累积的TSS量分别达到90%和75%。单位面积上的TSS冲刷量可以更好地描述子流域的污染水平,进而为流域面源污染治理提供科学依据。

Urban non-point source pollution is becoming more and more serious due to the rapid urbanization. Consequently, estimation of the non-point source pollution load and its source analysis have attracted widespread attention in the treatment of the non-point source pollution. The pollution load model for the two rainfalls in Panxi river basin in Chongqing was developed. The TSS concentrations during the two rainfalls were estimated. The TSS loads of each sub-catchment were calculated. The results showed that the built model could well simulate the production and collection process of the non-point source pollution, especially with higher simulation accuracy of the first flush process during the initial rainfall. During the two rainfall events, there were obvious first flush effects. In the first 30% of the runoff, TSS during the two rainfalls could reach 90% and 75% respectively. The removal rate of TSS per unit area could better describe the pollution levels of each sub-catchment, and then provide the scientific basis for watershed non-point source pollution control.