闸坝河流河道内生态需水研究——以淮河为例

提出了一种估算闸坝下游河道内生态需水的方法--改进的生态水力半径法（AdaptedEcologicalHydraulicRadiusApproach,AEHRA）,该法能够同时计算输出相应河段的生态水位,方便对闸坝进行调度。将其应用到淮河,以鱼类作为生态保护目标,估算了上、中、下游共4个典型闸坝下游河段的生态需水和生态水位,结果表明:①鱼类产卵期内需要较大的生态流量,其顺序为:蚌埠>周口>颍上>白龟山,下游大于上游,中游居中,受断面影响显著;非产卵期则为:周口>颍上>蚌埠>白龟山,中游大于上下游,受河流鱼种影响较大。周口闸下河段全年各月生态需水量相同,需加强上游闸坝的联合调度满足冬季12~-月的生态需水;②要维持河道内生态流量,需进行闸坝调度调整下游水位,保证生态水位;③淮河受人类活动影响剧烈,河流的连续性被切断,生态需水变化没有连续性,只有根据最小生态水位通过闸坝调度,维持河道生态系统最小生态需水,才能逐步恢复淮河健康生态。

Instream Ecological Flow of Dammed River-A Case Study of Huaihe River

We present a method for dammed river Instream Ecological Flow(IEF)-Adapted Hydraulic Radius Approach(AEHRA).This approach can compute Instream Ecological Water-level(IEW) as well as IEF.We applied this method to the Huaihe River to compute the ecological flow of four typical river-sections respectively in the upper,middle and lower reaches of the Huaihe River taking fishes as target species.Results show:(1) in the spawning season IEF is greater than that in the non-spawning season and IEF downstream is greater than that upstream,IEF in the middle reach is between them-IEF is mainly affected by the form of the river course cross-section;in the non-spawning season,IEF in the middle reach is greater than that downstream and upstream-IEF is mainly influenced by fish types;(2) dam operation is necessary to keep IEW corresponding to IEF;(3) the Huaihe River is greatly affected by human beings and the continuum is destroyed,which results in the appearance of no order in IEF change from upstream to downstream.Only when IEF has been satisfied through dam operation,will riverine aquatic ecologic restoration be possible to realize.