金沙江下游溪洛渡-向家坝梯级生态调度研究

A Study of Ecological Operation of Xiluodu-Xiangjiaba Cascade Reservoirs on the Lower Jinsha River

金沙江下游区域是我国重要的珍稀鱼类保护区,随着梯级电站的修建,势必将对生物的生存环境造成影响。为了减少负面的生态影响,利用年内展布法和改进FDC法计算了最小生态流量和适宜生态流量过程。根据不同的生态流量约束,设置了4种约束方案:(1)工程规划约束;(2)年内展布法计算的最小生态流量约束;(3)改进FDC法计算的最小生态流量约束;(4)改进FDC法计算的适宜生态流量约束。并对建立的生态调度模型进行求解,计算结果表明:当设置最小生态流量约束时,各典型年的发电量基本都能达到最大值;当设置适宜生态流量约束时,各典型年的发电量都有所减少。各方案的拟合优度的计算结果表明,在适宜生态流量约束条件下,水库的下泄流量更贴近天然的入库径流。

The lower Jinsha River is one of the conservation areas of rare fishes in China. With the construction of cascade reservoirs, it will definitely have negative impacts on the aquatic biota. To mitigate those negative effects, the dynamic calculation method and a modified FDC method are employed to calculate the minimum and appropriate ecological flow of Jinsha River. According to different ecological demands, four types of constraints are settled respectively, engineering constraint, minimum ecological flow constraint calculated by dynamic calculation method, minimum ecological flow constraint calculated by a modified FDC method, appropriate ecological flow constraint calculated by a modified FDC method. Then a reservoir operation model coupled with ecological demand is developed. The result shows that, under the minimum ecological flow constraint, most of the typical years can achieve the best power generation goal. But on the contrary, all of the typical years face a reduction in power generation under the appropriate ecological flow constraints. Further, the results of coefficient of determination of each scheme show that, under the appropriate ecological flow constraint, the outflow is more close to the natural inflow.