摘要
针对引水式电站的修建将造成坝下河道减脱水、危害减水河段内水生生物生存的问题,以雅砻江锦屏大河湾猫猫滩闸址至九龙河汇口36km减脱水河段为例,选取了1.75km的浅滩和2.12km的深潭生境河段作为鱼类栖息地评价的特征河段,采用单变量方法,在前人研究的基础上结合特征河段自然生境水力学特点,分析得出目标物种对水深及流速的适宜性曲线。并采用河道内流量增加法,建立了雅砻江锦屏大河湾特征河段鱼类栖息地模拟的River2D模型,确定了特征河段中目标物种适宜的栖息地面积变化情况,定性描述了鱼类适宜栖息地分布随流量变化的关系。研究结果表明,鱼类适宜栖息地随流量增大将由河道中间逐渐向边缘移动;在小流量时鱼类适宜栖息地面积增长迅速,随流量的进一步增大鱼类适宜栖息地增长速率明显减缓甚至基本不变,且当流量大于一定值时将会呈现负增长。
The discharge of lower reaches is reduced or vanished for construction of diversion type water power station,which leads to threat survival of hydrobiont.Taking 36 km reducing reach from Maomaotan dam to Jiulong river estuary in the Jinping Dahewan of the Yalong river for an example,1.75 km riffle habitat and 2.12 km pool habitat are selected as the characteristic reaches of fish habitat evaluation.Habitat suitable Index（HSI） is analyzed and obtained by using the univariate curve method.River2D model is built to simulate fish habitat in the reducing reach by using instream flow incremental methodology （IFIM）.The change of the weight usable area（WUA） is obtained when the discharge is changed.And distribution conditions with the flow changed is qualitative described.The research results show that the usable habitat will transfer from the middle channel to the both banks with the discharge increasing gradually;the growth of the WUA is rapid when the discharge is low;the growth of the WUA is obviously slow down when the discharge is biggish,even change little;and the growth will be negative when the discharge increases to a certain threshold.
出处
《水电能源科学》
北大核心
2011年第3期40-43,共4页
Water Resources and Power
基金
国家自然科学基金资助项目(50709023)
