Renmin Zhujiang (Jan 2022)
Research on the Calculation and Safeguarding of Minimum Ecological Flow of Rivers with Cascade Small Hydropower Development
Abstract
Small hydropower plays an important role in China’s hydropower resources.However,it inevitably affects the water ecological environment downstream adversely during its construction and operation.Calculating the minimum ecological flow can reduce such effects of small hydropower during its operation.Taking the main stream of the Dongjiang River,where cascade small hydropower development is carried out,as an example,this paper calculated its minimum ecological flow respectively by the improved Tennant method,QP method,empirical method,frequency curve method,and NGPRP method.Under the condition of a 95% guarantee rate,the above five calculation results were compared and analyzed.The minimum ecological flow value of 232.81 m3/s calculated by the QP method was selected as the lower limit of the minimum ecological flow,and the inner envelope line of the improved Tennant method and the frequency curve method was selected as the monthly minimum ecological flow process.Safeguard measures for the minimum ecological flow of the main stream of the Dongjiang River were put forward to ensure the healthy and sustainable development of small hydropower and the water ecosystem of the river.
