水生植物对氮和磷去除效果的试验研究

在城市河流水体旁边设计并构建了梭鱼草、茭草、香蒲三种挺水植物湿地以及苦草沉水植物湿地．研究了挺水植物湿地、沉水植物湿地对城市富营养化河流水体氮、磷的净化效果，并对其净化机理进行探讨。结果表明：（1）挺水植物湿地、沉水植物湿地对各种形态的氮、磷营养物质均有显著的去除效果，但沉水植物湿地对营养物的去除能力要高于挺水植物湿地；（2）沉水植物湿地内的溶解氧、pH值明显地高于挺水植物湿地，这主要是由于沉水植物生长茂密，通过光合作用向水体释放氧气的能力明显地高于挺水植物；（3）由于沉水植物湿地内的溶解氧高，因而通过硝化反应对氮的去除作用比较明显。

Study on aquatic macrophytes for purification of eutrophic water

In 4 laboratory-scale man-made wetlands,which include 3 emergent macrophyte(mullet grass,wild rise and cattail) man-made wetlands and 1 submergent macrophyte(ell grass) man-made wetlands,nutrient removal tests were conducted.The purpose of this investigation was to find a new way to treat the eutrophic river water in cities and,further more,to study the purification mechanism of the man-made wetlands.Significant roles of removing nitrogen and phosphorus were found in all the wetlands.The best removal rate was obtained in the submergent macrophyte wetlands,which had a higher removal rate of nutrients than that of emergent macrophyte and higher level of Dissolved Oxygen(DO) and pH due to its larger capacity of oxygen releasing via photosynthesis.It can be concluded that the man-made wetland systems can be utilized as a suitable solution for water purification.