基于GIS和SWMM模型的大清河流域面源污染风险评估

构建“三水统筹”(水资源、水环境、水生态)的北京市水环境承载力评价指标体系,基于层次分析法确定各指标权重,建立了水环境承载力大小的综合指数评价模型。对密云区水环境承载力进行了综合评价,结果表明:密云区水环境承载力综合评价等级为高承载,在北京市处于较高水平;但是水资源与水生态方面仍然存在不足,单项指标评价结果显示,水资源开发利用率、河流连通性分别为中承载、低承载状态,是影响水环境承载力的主要因素。为了进一步提升密云区水环境承载力,提出应通过节水和河流水生态修复等措施,全面改善密云区水资源和水生态状况。同时,应建立完善的水环境承载力监控预警机制,包括定期更新承载力评价结果等,为密云区发展提供应有的指导和引领。

This paper combines GIS and SWMM model to establish the non-point source pollution model of the Daqinghe River basin,explores the non-point source pollution load of the Daqinghe River basin in 2020.The spatial distribution of agricultural non-point source pollution load in the Daqinghe River basin is quantitatively studied by using the principal component analysis method and the cluster classification model.On this basis,the risk level is divided into strong risk area,medium risk area and low risk area.Based on the statistical yearbook data,the output coefficient method is used to estimate the pollution load of chemical fertilizer application,livestock and poultry breeding,rural domestic sewage,and aquatic product breeding in the Daqinghe River basin,and a technical system for monitoring agricultural non-point source pollution is established to provide theoretical support for the treatment of agricultural non-point source pollution in the Daqinghe River basin.