密云水库流域非点源污染研究概述

密云水库是现阶段首都北京惟一的地表饮用水源地,非点源污染是影响水库水质的主要因素.为明晰密云水库流域非点源污染的基本特征及其研究进展,本文总结了近20年来对水库流域非点源污染的研究成果,从非点源污染调查、非点源污染的负荷与预测评价、非点源污染物的影响因素与机理、非点源污染的控制管理等4个方面进行了概述.初步明确了密云水库流域非点源污染的基本特征,包括非点源污染主要来自于水土流失、化肥农药的施用、山区养殖产生的畜禽粪便、水产养殖等,其污染负荷随年度降雨变化较大,对水库污染总负荷的贡献COD约70%、BOD,约70%、NH,-N约90%、TN约70%、TP约90%等.预测了水库流域非点源的发展趋势.评价了非点源污染治理各项技术措施和政策管理措施的效果,并从非点源污染具体来源、污染途径和机理、研究尺度等方面提出了现阶段非点源污染研究存在的问题和需要进一步研究的方向.

Review on non-point source pollution in Miyun Reservoir

Miyun Reservoir is a unique surface water source of table-water for Beijing City, where most pollutants contaminating the reservoir are from non-point sources (NPS). This paper reviews a number of recent studies on NPS pollution in the watershed from the pollutant load and distribution, evaluation and prediction; and summarizes the factors and mechanisms of pollution as well as pollution control and management strategies. NPS pollution mainly comes from soil erosion, irrational chemicals utilization, livestock and poultry wastes, and byproducts of aquaculture. About 70% COD, 70% BOD₅, 90% NH₃-N, 70% TN and 90% TP in the reservoir water come from NPS pollution; but NPS pollutant load differs with precipitation, land use type, chemical load, degree of crop cover, etc. Along with the prediction of the trend of change of NPS pollutants, the findings and limitations of the studies are discussed and prospective pollution control, water quality protection and future research directions proposed. It is suggested that further studies should be conducted on agricultural NPS pollution, the process of pollutant movement, the change mechanism of pollution concentration and their management strategies.