中文摘要：

由于水文情势中的径流过程是影响河流生态系统改变的主要因素,有必要研究龙滩水库建坝前后径流过程的变化.依据建库前后天峨站1980年~2003年和2007年~2015年两个系列逐日径流实测数据,以IHA指标体系为基础,采用可变范围（RVA）法通过分析32个水文改变指标,评估了龙滩水库建设与运行之后下游水文情势特征的变化.计算结果表明：红水河天峨站水文情势综合改变度为70.49%,属于髙度改变.水库修建后对逐月径流量、年极端流量及其出现时间、流量频次和延时、流量改变率和频度产生了显著影响.通过对建坝带来的流域水文情势改变情况的分析,为流域管理部门制定合理的水库生态调度方案提供决策支持.

英文摘要：

Because the hydrological regime in the runoff process is the main factor affecting river ecosystem, it is necessary to study the change of runoff process before and after the construction of the Longtan Reservoir. According to the two series of daily runoff data of Tian’e station from 1980 to 2003 and 2007 to 2015 which based on the index system , Indicators of Hydrologic Alteration, the characteristics changes of the downstream hydrological regimes after the construction and operation of Longtan Reservoir were evaluated by the Range of Variability Approach through the analysis of 32 hydrologic indexe s. Calculated results show that the comprehensive change of hydrological regimes in Tian,e Station of Hongshui River is 70.49 % , which is high , and the reservoir construction has a significant effect on monthly runoff, annual extreme flow and its time of occu rren ce, flow frequency and its time delay and flow change rate and its frequency. By analyzing changes of hydrological regime caused by the dam construction, decision support can be provided for the river management departments to formulate reasonable reservoir ecological scheduling scheme.