江滩湿地水生植物对水体氮、磷污染物去除效果分析

Effect of Aquatic Macrophytes in Tidal Wetlands on the Total Nitrogen and Total Phosphorus

在镇江内江边选择面积为9 048 m2的水面建立中试试验区,分别引种挺水植物群落、浮叶植物群落、沉水植物群落,于2006年8月底引长江水进入实验区后对各植物群落进水与出水断面水体TN,TP浓度进行监测。结果表明:水体进入实验区时,TN浓度平均值为1.13 mg/L,输出时挺水植物群落、浮叶植物群落、沉水植物群落出水断面浓度平均值分别为0.67 mg/L,0.52 mg/L,0.43 mg/L,TN截留率依次为41%,21%,16%,不同植物群落对TN截留效果不同,其中挺水植物群落】浮叶植物群落】沉水植物群落。水生植物对水体TP去除效果显著,引长江水进入实验区时水体TP浓度平均值为0.19 mg/L,输出时挺水植物群落、浮叶植物群落、沉水植物群落出水断面TP浓度平均值分别为0.13 mg/L,0.09 mg/L,0.06 mg/L,各植物群落对TP截留率分别为31%,32%,31%。水生植物对水体TN,TP有明显去除效果,不同水生植物群落对防止水体富营养化起到积极作用。

The field experimental region which was 9 048 m2 was built in the inner river of Zhengjiang on August in 2006 and different types of aquatic macrophytes containing emergent plant community,submerged plant community and floating plant community were introduced in order to monitor and research the effects of different types of aquatic macrophytes on removing the total nitrogen and the total phosphorus in water body.The result shows that total nitrogen content in the inflow side was 1.13 mg/L and in the different outflow side was 0.67 mg/L,0.52 mg/L,0.43 mg/L respectively.The removal efficiency was different in three aquatic macrophytes community and the order was the emergent plant community>floating plant community>submerged plant community.The total phosphorus of water body was influenced significantly by aquatic macrophytes.The total phosphorus content after running through the emergent plant community,floating plant community and submerged plant community was 0.13 mg/L,0.09 mg/L,0.06 mg/L respectively.In general,aquatic macrophytes could remove the total nitrogen and the total phosphorus obviously,and different plant communities have played a positive role in prevention of water eutrophication.