中文摘要：

为评价西藏水电开发对河流生态环境的影响，根据西藏地区独特的地理气候条件，结合当地社会经济发展特点，构建包含水环境、生态环境和社会环境3个方面22个要素的水电开发对河流生态环境影响评价指标体系。综合考虑多方面因素确定指标的分级标准；采用综合指数方法构建评价模型，将评价结果分为影响很小、影响较小、一定影响、影响较大、影响很大5个级别。满拉电站实例分析结果表明，水电开发对该电站影响很小，符合实际情况。

英文摘要：

In order to evaluate the impact of hydropower exploitation on a river＇s ecological environment, we established an evaluation index system, which includes 22 factors falling within the scopes of the water environment, ecological environment, and social environment, based on the unique geographical and climatic conditions and social and economic development in Tibet. With comprehensive consideration of various factors, we determined the standards for classification of the indices. We used the comprehensive index method to construct the evaluation model, and classified the evaluation results into five categories：insignificant influence, less insignificant influence, moderate influence, less significant influence, and significant influence. A case study at the Manla Hydropower Station showed that the exploitation of hydropower had little impact on the station, and the application results were consistent with the actual situation.