基于流域分析方法的湖泊水污染综合防治研究

鉴于流域思想在水污染防治中应用的重要性和必要性,提出了以流域保护方法、流域分析和景观生态学相关理论为基础的流域分析方法该方法将湖泊-流域水污染综合防治的主要内容界定为4部分:子流域划分与污染负荷预测,"源-途径-末端-汇"的污染防治工程和管理方案体系设计,备选技术方案的提出和方案优选,污染负荷的削减率计算和综合方案设计.以四川省邛海流域为例,在将流域划分为6个子流域的基础上,对TP入湖污染负荷进行了计算和预测,并识别出各子流域内污染物的贡献率,分区提出了以水土流失防治、点源和面源控制、河道生态修复、河流入湖口治理和内源疏浚为主体的污染防治方案,该方案可削减TP 22.5 t·a-1,达到了预期目标.

Watershed approach as a framework for lake-watershed pollution control

Based on watershed characterization, watershed-protection principle, and landscape-ecology theory, a framework of watershed approach for water pollution control in a lake-watershed system is proposed in this study. The main procedures of the watershed approach include: (1) dividing watershed into sub-basins and forecasting pollutant load from each sub-basin to the lake; (2) designing pollution control strategies consisting of source prevention, process elimination, endpoint control and sink improvement; (3) recommending the desired comprehensive-pollution-control strategy; (4) calculating the reduction rate of pollutant load. The proposed method was applied to water pollution control for the Lake Qionghai Watershed in Sichuan Province, China. The watershed is divided into six sub-basins. TP loading from each basin to the lake in 2015 is predicted and analyzed. Based on the prediction results, water pollution control strategy, which mainly consists of soil-erosion prevention, point- and nonpoint-source control, river-channels ecological-restoration, and benthic-mud dredging, are recommended for the lake-watershed system. The reduction amount of TP under the recommended strategy is 22.5 tonne per year so that the target of environmental capacity can be reached.