沙颍河周口闸的建成运行，使得下游河流水文情势发生较大改变，对其水生态系统结构功能产生了显著影响。为定量评价周口段的水文情势变化，选取周口水文站1951-2016年的日径流资料，采用RVA法评估水闸建成前后33个水文指标的改变度及其生态影响。结果表明：（1）1975年后，人类活动尤其是周口闸的运行对沙颍河干流水文情势影响加剧，月均流量均呈明显下降趋势，河道内多次出现断流情况；（2）周口站的整体水文改变度为42.23%，属于中度改变，其中11月月均流量、最小1 d流量出现时间和流量下降率受到的影响最为强烈，为高度改变；（3）沙颍河流域水资源供需矛盾突出，水闸的运行调度对水生态系统的稳定性产生不利影响，迫切需要对沙颍河进行生态修复，对河流流量适时调整，实现区域经济和水生态系统协调发展。

The construction and operation of Zhoukou sluice on Shaying river has caused great changes in the flowing regime of the lower reach,which has a significant impact on the [JP2]structure and function of the water ecosystem in the basin.In order to evaluate the hydrological changes of Zhoukou reach quantitatively,daily runoff data of Zhoukou gauging station from 1951 to 2016 is selected,and the degree [JP]of 33 hydrological alteration indexes and their ecological influences before and after the construction of Zhoukou sluice in the middle reaches of Shaying river were evaluated through Ranges of Variability Approach (RVA) method.The results indicate that:(1) after 1975,the operation of Zhoukou sluice,human activities had an intensified influence on the flow regime of Shaying River,and the median value for each month showed a significant downward trend;(2) the overall degree of hydrologic alteration of Zhoukou gauging station is 414%, which is a moderate change,and the most significant changes occurred on the average flow in November,the timing of annual 1day minimum discharge and the flow fall rates,which were [JP2]strong changes;(3) The water supply and demand of Shaying River are in serious contradiction,and the operation and dispatching of sluice has adverse effects on the stability of water ecosystem.Therefore,it is urgent to carry out ecological restoration of Shaying River,adjust river flow timely,and realize coordinated development of regional economy and water ecosystem.

国家重点研发计划（2017YFC0404506）；国家科技重大专项（2017ZX07301003）;国家自然科学基金（51309253）;蚌埠学院科学研究项目（2018ZR01;2017ZR21）