密云水库及其流域营养物集成模拟的情景分析研究

在密云水库水环境模拟预测集成模型的支持下,考察了不同点源、非点源污染负荷控制措施对水库水质的影响和作用,制定了4个情景方案.基础情景分析表明,密云水库TN超标严重,TP相对较好,叶绿素浓度超过10μg/L的区域主要集中在潮河库区,而且面积较大.情景1、情景2和情景3是考虑了不同点源、非点源管理措施后的密云水库水质状况.结果表明,营养负荷的下降能显著地改善水体水质,尤其是磷负荷的降低可有效地制约藻类生长,叶绿素浓度显著降低,超过10μg/L的区域缩小甚至消失.这一结论说明了加强密云水库流域及周边地区工业、生活和畜禽养殖等点源和农业非点源污染控制对改善密云水库水质的有效性和必要性.

Scenario Analysis of Integrated Model of Nutrients in the Miyun Reservoir and Its Watershed

Supported by the integrated model of nutrients for the Miyun Reservoir in part I, effects of different control measures were studied on the water quality of the reservoir. Four scenarios were assumed and analyzed. Results of the base case scenario showed that TN concentration of the Miyun Reservoir had highly exceeded the environmental quality standard for surface water, and TP was relatively better. Furthermore, there were many regions that chlorophyll-a concentration exceeded 10 microg/L in the reservoir, and centralized in the reservoir area of Chaohe River. Scenario 1, 2 and 3 investigated effects of different pollution control measures on the water quality of the reservoir. Results showed that the control of nutrient input loads could improve the water quality greatly, especially control of TP loadings would limit algae growth effectively, and regions that chlorophyll-a concentration exceeded 10 microg/L even disappeared. The results indicated that some control measures, such as changing farming style, part treatment on stockbreeding pollution and reducing point source pollutant loadings were very effective and essential to decrease the eutrophic level of the reservoir.