减水河段水力生态修复措施的改善效果分析  

Effectiveness of hydraulic ecological rehabilitation measures in flow reduced river reaches

作　　者：王庆国[1,2] 李嘉[1] 李克锋[1] 邓云[1] 

机构地区：[1]四川大学水力学与山区河流开发保护国家重点实验室,四川成都610065 [2]四川大学建筑与环境学院,四川成都610065

出　　处：《水利学报》2009年第6期756-761,共6页Journal of Hydraulic Engineering

基　　金：国家自然科学基金资助项目(50709023)

摘　　要：通过二维水力模拟计算,对深槽和挡水堰不同组合的修复方案,即在河道横断面上设置深槽以及纵向上间隔设置挡水堰等工程措施,对减水河段的水力生态修复措施进行研究。以四川某山区河流一段120m长的河段为例,根据代表鱼类对水深、流速适应度的曲线,计算出权重可使用栖息地面积(WUA),并使用其来分析生境改善效果,同时还对影响河段沿程增温率的水力参数进行了对比分析。计算结果表明:在河道流量为1.65m3/s(约为多年平均流量的5%)时,采用深槽修复可增加WUA约48%,再在深槽基础上设一道拦水堰后共可增加WUA约84%;同时深槽还可使河流沿程增温率下降,使水温更接近减水前的状况。采用多道拦水堰将有助于尽可能多地提高栖息地面积,但拦水堰间距也不应过小,该河段拦水堰间距在30m左右为宜。分析表明,采用深槽加多道拦水堰的水力生态修复措施可以起到明显改善减水河段生境状况的作用。The two-dimensional hydrodynamics model was used to study the effect of hydraulic ecological rehabilitation measures such as setting deep grooves in river channel and establishing water-retaining weirs on flow reduced river reaches. As a case study, the weighted usable area （WUA） for representative fish in a 120m-long mountainous stream, situated in the Sichuan Province, were calculated according to its habitat suitability related to water depths and flow velocities. The results were used to analyze the effect on habitat rehabilitation and the temperature increasing rate along the longitudinal flow direction. It is found that when stream flow is 1.65m^3/s （about 5% of annual average flow）, the WUA will increase by 48 % for the measure of setting deep grooves. While the WUA will increase by 84 % if the measure of both setting grooves and a water retaining weir were adopted, and the water temperature will be reduced to the level before the flow to be reduced. The WUA will increase with the number of water-retaining weirs, but the interval must be controlled not less than 30m. It is concluded that the measures of setting deep grooves and establishing water-retaining weirs can significantly improve the situation of eco-environment of flow reduced river reaches which are effective for ecological rehabilitation.

关 键 词：水力生态修复 减水河段 权重可使用栖息地面积 设置深槽 拦水堰 河流水温 

分 类 号：X171.4[环境科学与工程—环境科学]