中文摘要：

通过对洋河水库表层底泥中的重金属元素及营养盐的分析，揭示其空间分布特征。采用潜在生态风险指数和地积累指数两种指标相结合的方法对表层底泥中重金属污染程度进行评价，同时采用有机指数法对表层底泥的肥力状况进行评价。结果表明，洋河水库的重金属污染主要以汞元素为主，并依据潜在生态风险指数将水库分为2个生态风险功能区：西河口和东河口轻污染区、引水口和水库中心中等污染区。底泥有机指数相当高，整个库区都处于Ⅲ级，水库平均有机指数高达0.244，水库底泥肥力较高。

英文摘要：

The content of copper, arsenic, chromium, mercury, total nitrogen, total phosphors and organic matter of surface sediments in Yanghe reservoir were quantitatively analyzed. Their plane distribution characteristics in surface sediments were analyzed using Surfer software. The pollution degree of heavy metal in the surface sediments was evaluated by the geological acumination index （Igeo） and the potential ecological risk index （RI） respectively. Finally, the fertility of the sediments was assessed using the organic index. The results showed as follows： ① Mercury was the main heavy metal pollutant in the surface sediments; ② The Yanghe reservoir could be divided into two sections according to the potential ecological risk index： light pollution area in northwest part and northeast part and medium pollution area in southeast part and central part; ③The average organic index of the surface sediments in Yanghe reservoir was 0.244, indicating that the surface sediments were very fertile.