中文摘要：

黄河上游梯级水库在发挥防洪减灾、发电、灌溉等作用的同时,使黄河上游河段生态水文特征发生了较大变化,给黄河生态环境健康带来了一定的负面影响。以黄河上游代表站点兰州站为例,使用TFPW-MK突变检验法和秩和检验法分析其水文序列的变异点位置,采用水文指标改变法（IHA）分析变异前后水文生态指标的变异范围。结果表明：兰州站水文序列在1985年发生了变异,且水文变异程度较高,各项生态指标不同程度发生了改变,造成了水文生态条件的恶化。其主要原因是人类活动的影响。

英文摘要：

The upstream cascade reservoirs in the Yellow River play a role in flood control and disaster reduction, power generation, irrigation and so on, but at the same time, the ecological and hydrological characteristics of the upper reaches of the Yellow River have changed greatly, which has brought about some negative effects on the health of the Yellow River. This paper takes a typical station in Lanzhou in the upstream Yellow River as an example, uses TFPW-MK mutation test and rank sum test to analyze the loca- tion of the variation points of hydrological series. The variation range of hydrological ecological indexes before and after variation is analyzed by the method of Indicators of Hydrologic Alteration （IHA）. The results show that the hydrological series of Lanzhou Sta- tion mutated in 1985 with a high degree of hydrological variability. Various ecological indicators have changed to different degrees which has caused the deterioration of ecological conditions. The main reason is the influence of human activities.