滇中引水工程取水口下游金沙江生态流量研究

Study on Ecological Flow of Jinsha River in the Downstream of the Intake of Dianzhong Water Diversion Project

对拟建滇中引水工程大同取水口下游至虎跳峡前的43.5 km金沙江研究河段,采用流量历时曲线法和栖息地模拟法分别进行生态流量研究。栖息地模拟法选用目标鱼类长丝裂腹鱼,结合水动力学数值模拟与栖息地模型结合的方法,利用MIKE21建立研究河段的平面二维浅水水动力学模型。按长丝裂腹鱼对水深、流速的适宜度标准确定不同流量下的栖息地加权可利用面积(WUA),得到栖息地面积WUA随流量的变化趋势,最终确定目标鱼类产卵繁殖期适宜的生态流量值。比较2种方法的研究结果,取其中最大值作为最终生态流量值。

The ecological flow of 43. 5 km Jinsha River section from the downstream of the Datong Intake of the proposed Dianzhong Water Diversion Project to Hutiao Gorge is studied by using the flow duration curve method and the habitat simulation method respectively. The habitat simulation method selects the Schizothorax dolichonema Herzenstein as target fish,and combined with the method of hydrodynamic numerical simulation and habitat model,the MIKE21 model is used to establish a two-dimensional shallow water hydrodynamic model for the study of river section. The habitat weighted usable area( WUA)under different flow is determined according to the suitability standards of water depth and flow velocity of the target fish,and the change trend of habitat area WUA with flow is obtained. Finally,the suitable ecological flow value for the target fish in spawning period is determined. According to the calculation results of two methods,the maximum value is taken as the final ecological flow value.