关键词: 生态流量;生态需水量;水文节律;生态流量满足度;适用性指数;水文学法;雅砻江;

Abstract: Ecological flow is very important for maintaining the stability of basic ecological functions and river health. In order to determine the optimal ecological flow of Yajiang Station in the middle reaches of Yalong River, seven hydrological methods including Tennant method, minimum monthly average flow method, Q90 method, Texas method, monthly frequency calculation method, NGPRP method and ABF method were compared and analyzed from three aspects: water quantity demand, hydrological rhythm and satisfaction degree of ecological flow. An applicability index for ecological flow calculation method based on fuzzy optimization method was constructed to select the most reasonable ecological flow calculation method in the study area. The results showed that: ①The ecological flow calculated by ABF method and monthly frequency calculation method was almost equal to the measured mean monthly flow, and their satisfaction degree in fish spawning period was low. ②The ecological flow calculated by Q90 method cannot reflect the natural change process of runoff and was not applicable to this reach. ③The improved minimum monthly average flow method and NGPRP method could not meet the requirements of water quantity in fish spawning period. ④The applicability index of Texas method was the highest, which could be used to calculate the ecological flow in the middle Yalong River. The research results can provide reference and data support for ecological dispatching of water conservancy project in the middle Yalong River.

Key words: ecological flow; ecological water demand; hydrological rhythm; satisfaction degree of ecological flow; applicability index; hydrological method; Yalong River