河流保护与生态修复

分析了堤防和水坝对河流造成的负面影响:切断了河流横向和纵向的生态联系,造成水文循环短路和绝缘,河流被台阶化、节点化,从而破坏了水滨生物栖息地和水生生态系统。从河流保护概念性范围出发,分析了河流在横向、纵向、垂向以及时间维度上的水文循环和生态联系。指出恢复河流生态系统的根本思想在于推动和恢复河流在空间和时间的4维尺度上的水文循环和生态联系,避免河流水文循环短路或绝缘。总结了国内外关于河流生态修复的措施,即在河流横向营造生物栖息地、湿地、林地、深潭和浅滩等,在河流纵向补偿流量和洪水过程,重建生物栖息地和水库消落带,闸坝处建造鱼道和鱼梯等。

Stream protection and ecological rehabilitation

An analysis was made of the negative influences of embankment and dam projects on the evolution of streams,and some conclusions were drawn.Embankments and dams severed hydrological cycle and ecological connection and resulted in shortening of hydrological cycle and insulation of streams;the evolution of streams in terrace and node forms destroyed riparian habitat and aquatic ecosystem.Through an analysis of hydrological cycle and ecological connection of streams in lateral,longitudinal,vertical,and temporal dimensions based on the concept extension of stream protection,it is pointed out that the essential thought for stream ecosystem rehabilitation should be placed on recovery of hydrological cycle and ecological connection in four dimensions and avoiding of shortening of hydrological cycle and insulation of streams.Furthermore,measures for stream ecosystem rehabilitation at home and abroad were summarized,including construction of habitat,wetland,woodland,pool,and shoal on lateral dimension of streams and compensation of runoff and flood,rebuilding of habitat in reservoir area and vegetation in fluctuating belt of reservoir area,and construction of fish way and fish ladder on longitudinal dimension of streams.