Nitrogen transformations and balance in constructed wetlands for slightly polluted river water treatment using different macrophytes.
Nitrogen removal processing in different constructed wetlands treating different kinds of wastewater often varies, and the contribution to nitrogen removal by various pathways remains unclear. In this study, the seasonal nitrogen removal and transformations as well as nitrogen balance in wetland microcosms treating slightly polluted river water was investigated. The results showed that the average total nitrogen removal rates varied in different seasons. According to the mass balance approach, plant uptake removed 8.4-34.3 % of the total nitrogen input, while sediment storage and N(2)O emission contributed 20.5-34.4 % and 0.6-1.9 % of nitrogen removal, respectively. However, the percentage of other nitrogen loss such as N(2) emission due to nitrification and denitrification was estimated to be 2.0-23.5 %. The results indicated that plant uptake and sediment storage were the key factors limiting nitrogen removal besides microbial processes in surface constructed wetland for treating slightly polluted river water.
Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100, People's Republic of China.
Haiming
H
Wu
Jian
J
Zhang
Rong
R
Wei
Shuang
S
Liang
Cong
C
Li
Huijun
H
Xie
D001673:Biodegradation, Environmental; D052918:Environmental Restoration and Remediation / Q000379:methods*; D009584:Nitrogen / Q000032:analysis / Q000378:metabolism*; D058458:Nitrogen Cycle; D018521:Plant Physiological Phenomena; D010944:Plants / Q000378:metabolism*; D045483:Rivers / Q000737:chemistry; D012621:Seasons; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000378:metabolism*; D018508:Water Purification / Q000379:methods*; D053833:Wetlands
D014874:Water Pollutants, Chemical; D009584:Nitrogen