中文摘要：

选取于桥水库上游控制断面--天津果河桥断面1999-2007年的水质监测资料为研究对象,统计该断面6项主要污染项目的超标情况,采用Kendall趋势检验方法对此6项监测指标的月序列进行趋势分析,研究这6项指标在丰水期、平水期、枯水期及年均值的变化趋势.通过分析果河桥断面水质超标情况及该断面主要污染物的变化趋势,得到于桥水库的富营养化特征,结合污染源调查,提出富营养化控制措施.结果表明：于桥水库富营养化的限制因子是磷元素,7-9月蓝藻暴发事件主要是由库区底泥中磷元素的释放所引起的,并且底泥中磷元素的释放受铁氧化-还原控制,上游来水中的铁元素对于桥水库蓝藻暴发有着重要的影响作用.为了防止于桥水库出现藻类暴发的水质恶化事故,需要采取两种关键措施,一是严格控制上游选矿企业富含铁元素尾水的排放,以降低入库水流中铁元素的含量,二是采取底泥氧化或人工曝气等原位技术抑制底泥中磷的释放.

英文摘要：

The present paper intends to introduce our research of analysis and countermeasure research of yuqiao reservoir＇s eutrophication process. As is known, Yuqiao reservoir is located in the northem part of Tianjin, and in turn the main drinking water supply base of Tianjin city. For its importance for the city survival, we have adopted the water quality monitoring data from 1999 to 2007 of Guo-heqiao section, that is, the upstream section of the reservoir, to monitor the frequencies and ratio of the dominant pollution indices in accordance with the national standard pollution-control value. Then, Mann-Kendall method was introduced to analyze the monthly trend of the 6 pollution indices. Furthermore, these index-changing trends were studied respectively in the wet seasons, normal seasons, dry seasons and the whole year. Through our analysis of the chief con- taminants beyond the national pollution-control standard situations, we have obtained the reservoir＇ s eutrophication characteristics. Based on our investigation results of the pollutant sources, we have put for- ward some to change the situation of the of Yuqiao reservoir＇ s eutrophication. The characteristic analysis of its eutrophi- cation shows that the restraint factors of the reservoir＇s eutrophication process was phosphorus. Moreover, water algal blooms in Yuqiao reservoir during the period of the two months from July through September were chiefly caused by tile release of phosphorus in the reservoir＇s＇mud, whose release from the reservoir was controlled by the Oxidation-Reduction of ferro （ Fe ） ingredients. And, therefore, the Ferro in the upstream may have an important effect on the water algal bloom of the reservoir. To prevent the water from the algae eruption, we have taken two key to inhibit the re- lease of phosphorus in its sediment： one is to strictly control the sewage rich in Fe and the iron mine＇s activities to contaminate the water from the upstream inflow, the other is to apply the technology of sediment oxidation or arti