[In-situ remediation of polluted water body by planting hydrophytes].
In an experimental enclosure system, floating plant Eichhornia crassipes was planted in summer and submersed plant Elodea nutalli was planted in winter to reestablish water ecosystem, and to investigate the effects of the hydrophytes on the removal of nitrogen and phosphorus from polluted water body and the improvement of water transparency. The results showed that compared with the control and native pond water, the water body planted with hydrophytes had a low level of nutrients. E. crassipes had a fast growth, with its covered area increased from 100 m2 to 470 m2 in the first 15 days, and to 65% of the water area after 44 days. The total nitrogen, ammonium nitrogen, nitrite nitrogen, CODMn and chlorophyll a decreased to a lower level, and the water transparency increased significantly, reaching to a depth of 1.7-1.8 m (i.e., to the bottom of the pond). After October, the total phosphorus kept on about 0.1 mg L(-1). Due to the increased water transparency, E. nutalli became the dominant species and covered 1/3 of the water area, playing an important role in purifying water quality, keeping water physicochemical properties in good status, and improving water transparency. It was concluded that planting hydrophytes in polluted water body could efficiently reduce its nutrients level and control the overgrowth of algae, being an important way in improving the water quality of eutrophicated water body.
Fang
Yun-Ying
YY
Key Laboratory of Environmental Remediation and Ecosystem Health of Education Ministry, Institute of Agricultural Chemistry, College of Environment and Resource Science, Zhejiang University, Hangzhou 310029, China. fangyunying@yahoo.com.cn
Yang
Xiao-E
XE
Chang
Hui-Qing
HQ
Pu
Pei-Min
PM
D001673:Biodegradation, Environmental; D031806:Eichhornia / Q000254:growth & development / Q000378:metabolism*; D052918:Environmental Restoration and Remediation / Q000379:methods; D005068:Eutrophication; D031321:Hydrocharitaceae / Q000254:growth & development / Q000378:metabolism; D009584:Nitrogen / Q000378:metabolism*; D014873:Water Pollutants / Q000378:metabolism*
D014873:Water Pollutants; D009584:Nitrogen