基于SWAT模型污染防治措施对茫溪河水质改善影响研究

Study on Effects of Pollution Control Measures on Improvement in Water Quality in Mangxi River Based on SWAT Model

为了更好地开展茫溪河的污染防治,摸清茫溪河流域污染源贡献比例以及各种污防措施对水质改善效果十分必要。基于SWAT构建了茫溪河流域分布式水文和污染负荷模型,根据监测数据分析了茫溪河近年超标污染物,基于SWAT模型分析了茫溪河水质达标场景假设,包括污染源贡献率及生态补水、点源和面源等污染防治措施对水质改善的效果情况。结果表明,茫溪河流域超标项目集中在总磷和高锰酸盐指数;污染源中,面源相对于点源对高锰酸盐指数和总磷贡献率大些,特别是水土流失的贡献率最大,分别达到了42.8%和76.1%;生态补水对污染物浓度降低有一定影响,直排源和非直排源污染控制一定程度上使污染物浓度降低,达标率有所提升。基于SWAT模型的茫溪河水质达标场景分析对于推动水质改善具有积极的意义。

In order to control pollution of the Mangxi River effectively,it is essential to identify the contribution rates of pollution sources and the effects of various pollution control measures on improvement in the water quality.The distributed hydrological and pollution load model for the Mangxi River Basin was built based on the SWAT model.Excessive pollutants in the river were analyzed based on the monitoring data,and the hypothetical scenario in which the water quality of the Mangi River met the standard was analyzed based on the SWAT model,including the impacts of the contribution rates of the pollution sources and the effects of pollution control measures on improvement in the water quality,such as ecological water supplement and control measures for pollution from point sources and non-point sources.The results showed that the total phosphorus and permanganate were the main excessive pollutants in the Mangxi River Basin;the model analysis indicated that the contribution rate of non-point sources to the pollution of permanganate and total phosphorus was greater than that of point sources.In particular,soil and water erosion contributed the most to pollution,accounting for 42.8%and 76.1%,respectively;Ecological water supplement had a certain impact on pollutant concentration.The control of pollution caused by direct emission sources and non-direct emission sources reduced the concentration of pollutants and increased the rate of compliance with emission standards to a certain extent.Based on SWAT model,the analysis of the scenario in which the water quality of the Mangi River met the standard was of positive significance to improving the water quality.