中文摘要：

在总结、分析国内外相关研究成果的基础上，结合黄河生态水文特点，提出其指标体系构建原则，借助Pearson相关分析法提取并确定了可表征黄河河流生态水文情势的50个指标，构建了黄河生态水文评估指标体系，并将该指标体系应用于黄河干流兰州断面的生态水文评估。实例研究采用变化范围法进行评价计算，结果表明，兰州断面的整体水文改变度为0．722，即发生高度改变。其中1、2、8、9月平均流量、逆转次数、高流量延时、枯季最大流量、丰季最大流量发生时间、大小洪水次数、涨水次数与延时等指标改变强烈，将对黄河兰州段的水沙关系、生物种群数量、幼苗比例、栖息地环境以及滩区、湿地、洪泛区的植被与动物种类产生较大影响。与水文变化指标体系进行对比，发现两者评估结果基本一致，表明本文方法在实际应用中是可行的。同时，微观结果表明，本文方法相对水文变化指标体系更细致、更全面、更准确，可较好地反映黄河生态水文态势。

英文摘要：

Good eco-hydrological connection is essential to ensure the healthy of river ecosystem. In this pa- per, the related researches from the domestic and overseas were reviewed and discussed. Based on the anal- ysis of the Yellow River coo-hydrological characteristic, the principle for constructing the eco-hydrologic in- dex system was put forward. According to the principle, an eco-hydrologic index system with 50 indexes se- lected by Pearson Correlation Analysis method was given to characterize the Yellow River eco-hydrological situation. In order to understand the practicality of indicator system, it was applied to valuate the eco-hy- drological level of the Lanzhou Station in the main Yellow River. The case study results show that under the influence of human activities, the entirety of hydrological variability degree on Lanzhou station is 0.722. It indicates a high change on eco-hydrological condition occurred there. Among all changed indexes, the average flow on January, February, August, September, number of hydrologic reversals, mean or medi- an duration of high pulses, annual minima 1-day mean in dry season, date of each annual 1-day maxi- mum in rainy season, number of small and large flood, and number and duration of rising water have a high-degree change. These changes will result in the impacts on the relations among runoff and sediment, biological population, proportion of seedlings, habitat condition and vegetation and animal species in wet- lands and flood plain in the Lanzhou river reach. Comparing with the results obtained by the Indicators of Hydrologic Alteration （IHA）, which has been widely recognized around the world, two conclusions of as- sessment were basically the same. Further analysis shows that the current eco-hydrologieal index system can preferably characterize the situation of river eeo-hydrological condition of the Yellow River, which is more detailed, more comprehensive and more accurate than the IHA.