沉水植物及组合对城市缓滞水体水质的净化

Purification of Urban Stagnant Water Body by Submerged Plants and the Combinations

针对北京市永定河莲石湖主要沉水植物菹草,由于夏季演替导致水质净化效果降低,选用伊乐藻(Elodea canadensis Michx)、轮叶黑藻(Hydrilla verticillata)、苦草(Vallisneria natans)、轮叶狐尾藻(Myriophyllum verticillatum L.)及其组合,研究对水中TN、TP、NH_(3)-N、叶绿素a、DO等水质指标净化效果,根据试验结果选出适宜莲石湖菹草演替的组合。试验结果表明,4种沉水植物及组合对TN、TP、NH_(3)-N均有较好的去除效果,对叶绿素a有明显的抑制作用。在试验周期内,对TP处理能力最好的是苦草+轮叶黑藻+轮叶狐尾藻的组合,平均每株的处理能力为11.11 mg;对TN处理能力最好的是伊乐藻+轮叶黑藻+轮叶狐尾藻的组合,平均每株的处理能力为141.36 mg;对NH_(3)-N处理能力最好的是苦草+轮叶黑藻+轮叶狐尾藻的组合,平均每株的处理能力为96.12 mg。结合每种植物的生长情况和特性,优选补种苦草+轮叶黑藻+轮叶狐尾藻的组合作为莲石湖夏季菹草演替的方案。

In view of the problem that water purification effect of Potamogeton crispus,the main submerged plant in Lianshi Lake of Yongding River,in Beijing,was reduced due to succession in summer,Elodea canadensis Michx,Hydrilla verticillata,Vallisneria natans and Myriophyllum verticillatum L.were selected and its combinations study on purification effect of TN,TP,NH_(3)-N,chlorophyll,DO and other water quality indicators.According to test results,combinations suitable for the succession of Potamogeton crispus in Lianshi Lake was selected.Results showed that four submerged plants and their combinations had better removal effect on TN,TP and NH_(3)-N,and had obvious inhibition on chlorophyll.The best treatment capacity for TP was the combinations of Vallisneria natans+Hydrilla verticillata+Myriophyllum verticillatum L.,with an average treatment capacity of 11.11 mg per plant.The best treatment capacity for TN was the combinations of Elodea canadensis Michx+Hydrilla verticillata+Myriophyllum verticillatum L.,with an average treatment capacity of 141.36 mg per plant.The best treatment capacity for NH_(3)-N was the combinations of Vallisneria natans+Hydrilla verticillata+Myriophyllum verticillatum L.,with an average treatment capacity of 96.12 mg per plant.Based on above situation,combined with the growth and characteristics of each plant,the combinations of Vallisneria natans+Hydrilla verticillata+Myriophyllum verticillatum L.was selected as the succession plan of Potamogeton crispus in summer in Lianshi Lake.