基于变化范围法（RVA）的汉江支流生态流量研究

o solve the shortage of water resources in Guanzhong region, we will transfer water form Hanjiang River Basin where water resources are abundant to Guanzhong region where water resources are scarce. This measure will inevitably cause changes of stream discharge in Hanjiang River and its tributaries. The study will focus on Youshuihe River, which is on the left bank of Hanjiang River. We have collected the daily discharge records of Youshuijie Station for the period of 1958-2013, which are totally 35 years. Mann-Kendall and slide rank sum are used to analyze change-points of the annual runoff, the analysis shows that there are no significant change-point and the date can be used to compute the ecological streamflow. RVA is used to compute the ecological streamflow from Jan. to Dec. in Youshuihe River. Comparing with other hydrological methodologies, we come to a conclusion that the ecological streamflow computed by RVA can provide reference to the estimation of ecological streamflow in Youshuihe River, and it can also offer support to the water diversion of Huangjinxia Hydropower Station in Han-to-Wei Water Diversion Project.