Study on Fish habitat changes in reducing reach of long diversion type hydropower station

摘要

The discharge in the 119km reach of Jinping Dahewan has been reduced after construction of Jinping secondary hydropower station (JinPing II). The hydraulic habitats for fish has been destroyed, such as water depth, water velocity, water surface width, wetted perimeter rate, cross section area, water surface area, riffle, pool and so on. The living environment of Schizothorax is destroyed. The changes of hydraulic habitat parameters on the whole reach are considered based on the hydraulic calculate to the 119km reducing reach. The percentage conception of the reducing reach length of fulfilling the hydraulic habitat parameters is put forward'because the reducing reach caused long diversion type hydropower station is very long. It will be avoid that the results by the lower parameter value will conduce to misjudgement if some reducing reach of lower hydraulic habitat parameters is very short. The gained results on the changes offish habitat are more comprehensive.