河流多生境自然塑造技术在北运河流域再生水河道修复中的应用研究

Study on the application of river multi-habitat natural molding system to rivers replenished with reclaimed water in North Canal Watershed

遵循“基于自然的解决方案(Natural based solution)”理念,本研究开发了由渗滤型边滩、生态跌水和近自然河溪构成的河流多生境自然塑造技术及系统,并在北运河流域的再生水河道台头沟实施了工程应用与示范.结果表明,该技术与系统具有良好的水质净化效果,对氨氮、总氮、总磷和化学需氧量的平均削减率分别为62.15%、47.46%、48.50%和70.84%;河道修复使得生境质量得到改善,由D级(差)提升至B级(良),生境类型由不足3种提升至超过8种;修复后河道底栖动物的种类数量、BI指数、多样性指数等增加,水鸟从无到有,生物多样性也逐步改善.该技术可为城市特别是城乡结合部小型再生水河道治理提供借鉴.

According to the principle of Natural Based Solution,a river multi-habitat natural molding technology was advanced,which consists of percolation floodplain,ecological water falls and close-to-nature stream system.The technology was applied in Taitou stream which was a river restored by reclaimed water in North Canal Watershed.The practical application results showed that the multi-habitat natural molding system greatly improved the water quality,biology and habitat status.The removal rates of ammonia nitrogen(NH3-N),total nitrogen(TN),total phosphorus(TP)and chemical oxygen demand(COD)were 62.15%,47.46%,48.50%and 70.84%,respectively.The habitat quality rank in Taitou stream changed from the poor rank of D to the good rank of B.And the number of habitat types has exceeded 8,which was less than 3 before river restoration.The biology diversity also improved,where the quantity and biological integrity index of Macrobenthos increased,and different waterfowls were found.The study shows this technology is suitable for ecological restoration of small water bodies replenished with reclaimed water in cities especially in urban-rural fringe zone.