Examination of oxygen release from plants in constructed wetlands in different stages of wetland plant life cycle.
The quantification of oxygen release by plants in different stages of wetland plant life cycle was made in this study. Results obtained from 1 year measurement in subsurface wetland microcosms demonstrated that oxygen release from Phragmites australis varied from 108.89 to 404.44 mg O₂/m(2)/d during the different periods from budding to dormancy. Plant species, substrate types, and culture solutions had a significant effect on the capacity of oxygen release of wetland plants. Oxygen supply by wetland plants was estimated to potentially support a removal of 300.37 mg COD/m(2)/d or 55.87 mg NH₄-N/m(2)/d. According to oxygen balance analysis, oxygen release by plants could provide 0.43-1.12% of biochemical oxygen demand in typical subsurface-flow constructed wetlands (CWs). This demonstrates that oxygen release of plants may be a potential source for pollutants removal especially in low-loaded CWs. The results make it possible to quantify the role of plants in wastewater purification.
Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science & Engineering, Shandong University, Jinan, 250100, People's Republic of China.
Jian
J
Zhang
Haiming
H
Wu
Zhen
Z
Hu
Shuang
S
Liang
Jinlin
J
Fan
D001673:Biodegradation, Environmental; D010100:Oxygen / Q000032:analysis / Q000378:metabolism*; D006109:Poaceae / Q000254:growth & development / Q000378:metabolism*; D062065:Wastewater / Q000032:analysis; D018508:Water Purification; D053833:Wetlands
D010100:Oxygen; D062065:Wastewater