Investigating CH4 and N2O emissions from eco-engineering wastewater treatment processes using constructed wetland microcosms |
| |
| Institution: | 1. National Institute for Environmental Studies, Tsukuba 305-0053, Japan;2. Graduate School of Life and Environmental Sciences, Tsukuba University, Japan;3. Department of Chemical Engineering, Waseda University, Japan;1. College of Life Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, PR China;2. Department of Renewable Resourse, University of Alberta, Edmonton T6G 2E3, Alberta, Canada;3. College of Life Sciences, Taizhou University, Jiaojiang 318000, PR China;1. Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China;2. University of Chinese Academy of Sciences, Beijing, 100049, China;3. Jilin Provincial Engineering Center of CWs Design in Cold Region & Beautiful Country Construction, Changchun, 130102, China;4. Urban Pollution Research Centre, Middlesex University, Hendon, London, NW4 4BT, UK;1. College of Natural Resources and Environment, Northwest A & F University, Yangling, Shaanxi 712100, PR China;2. Department of Water Environment Research, Changjiang River Scientific Research Institute, Wuhan 430010, PR China;3. Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science & Engineering, Shandong University, Jinan 250100, PR China;4. School of Civil and Environmental Engineering, University of Technology Sydney, Broadway, NSW 2007, Australia;5. Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA 94720, United States;1. College of Life Sciences, Zhejiang University, Hangzhou 310058, PR China;2. School of Life Sciences, Taizhou University, Jiaojiang 318000, PR China;3. Northeast Institute of Geography and Agricultural Ecology (NEIGAE), Chinese Academy of Sciences, Changchun, Jilin 130012, PR China;4. Department of Renewable Resources, University of Alberta, Edmonton, Alberta, Canada T6G 2E3;5. School of Energy and Environment Engineering, Zhongyuan University of Technology, Zhengzhou 450007, PR China;1. College of Life Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, China;2. College of Life and Environmental Science, Wenzhou University, Wenzhou, 325035, China;3. College of Forestry, Beijing Forestry University, 35 Qinghua East Road, Beijing, 100083, China;4. Research Center for Ecological Protection and Climate Change Response, Nanjing Institute of Environmental Sciences, Ministry of Environmental Protection, 8 Jiangwangmiao Street, Nanjing, 210042, China |
| |
| Abstract: | Methane (CH4) and nitrous oxide (N2O) are important greenhouse gases, because of their contribution to the global greenhouse effect. The present study assessed emissions of N2O and CH4 from constructed wetland microcosms, planted with Phragmites australis and Zizania latifolia, when treating wastewater under different biological oxygen demand (BOD) concentration conditions. The removal rate was 95% for BOD and more than 80% for COD in all three pollutant concentrations, both plants’ removal rates of pollutants were at almost the same level, and both were found to resist BOD concentrations as high as 200 mg L?1. When BOD concentrations fell below 200 mg L?1, the soil plant units reached an average of 80–92% T-N and T-P removal rates; however, as the concentrations increased to 200 mg mg L?1 or when during the initial phases of winter, the removal rates for T-N and T-P decreased to less than 70%. With NH3-N removal, the influences of BOD concentrations and air temperature were more obvious. When BOD concentrations increased to 100 mg L?1 after October, an obvious decrease in NH3-N removal was detected; almost no nitrification occurred beginning in December at BOD concentrations of 200 mg mg L?1. N2O and CH4 emissions showed obvious seasonal changes; higher emissions were observed with higher BOD concentrations, especially among Z. latifolia units. The enumeration of methane-oxidizing bacteria and methane-producing bacteria was also conducted to investigate their roles in impacting methane emissions and their relationships with plant species. The pollutant purification potentials of P. australis and Z. latifolia plant units during wastewater treatment of different pollutant concentrations occurred at almost the same levels. The nutrient outflow and methane flux were consistently higher with Z. latifolia units and higher concentrations of BOD. The more reductive status and higher biomass of methanogens may be the reason for the lower nitrification and higher CH4 emissions observed with Z. latifolia units and higher concentration systems. The Z. latifolia root system is shallow, and the activity of methanotrophs is primarily confined to the upper portion of the soil. However, the root system of P. australis is deeper and can oxidize methane to a greater depth. This latter structure is more favorable as it is better for reducing methane emissions from P. australis soil plant systems. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
