微观世界
镁
湿地
机制(生物学)
磷
环境化学
人工湿地
环境科学
化学
化学工程
环境工程
生态学
废水
工程类
有机化学
生物
物理
量子力学
作者
Wei Lan,Jian Zhang,Zhen Hu,Mingde Ji,Xinwen Zhang,Jianda Zhang,Fazhan Li,Guoqing Yao
标识
DOI:10.1016/j.cej.2017.10.150
摘要
Abstract Over the past few decades, low phosphorus removal efficiency hampered the further application of constructed wetlands (CWs). In this study, magnesium (Mg)-containing materials, i.e., magnesia and magnesite, were added into CWs substrate to improve TP removal performance. Results showed that the average TP removal efficiency of magnesia group (MA-CW) reached 93.3%, which was 17.5% and 18.6% higher than that of magnesite group (ME-CW) and control group (QZ-CW), respectively. P fractionation analysis showed that the proportion of phosphorus sequestration by substrate in MA-CW was 90.4%, while it was only 65.1% and 58.8% in ME-CW and QZ-CW, respectively. Phosphorus assimilation by plant in ME-CW accounted for 9.52%, higher than other groups, which was attributed to the stimulated plant growth caused by Mg addition. The average total chlorophyll content of plants in ME-CW was 4.61 mg g−1 FW during the study period and the plant growth rate was superior to other groups, whereas in MA-CW, excessive alkaline (pH = 10.29) caused by MgO dissolution depressed plant growth. Mg addition also elevated the absolute abundance of (PAOs), which followed the order of MA-CW (1.76 ± 0.03 × 107 copies g−1) > ME-CW (1.35 ± 0.02×107 copies g−1) > QZ-CW (4.48 ± 0.13 × 106 copies g−1). Characterization of magnesia and magnesite before and after phosphate adsorption was compared and the results indicated that phosphorus adsorption by magnesium mainly relied on co-precipitation of Mg3(PO4)2 and MgHPO4, as well as ligand-exchange on the surface.
科研通智能强力驱动
Strongly Powered by AbleSci AI