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Xue R, Liu X, Fu X, Luo H, Zhang K, Anderson BC, Li M, Huang B, Yu L, Li X, Fu S, Pu A, Fan L, Chen W. Characteristics of methane emissions in the Living Water Garden in Chengdu City from 2012 to 2017. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:39531-39546. [PMID: 32651787 DOI: 10.1007/s11356-020-09679-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 06/10/2020] [Indexed: 06/11/2023]
Abstract
CH4 flux measured by a portable chamber using an infrared analyzer was compared with the flux by static chamber measurement for CW at 13 different sites from May 2012 to May 2017 in the Living Water Garden (LWG) in Chengdu, Sichuan Province, China, over 4 timescales (daily, monthly, seasonal, and annual). During the measurement period, a total of 1443 data were collected. CH4 fluxes were measured using the portable chamber method and the results showed that the annual mean and median CH4 flux values in the LWG were 17.4 mg m-2 h-1 and 6.2 mg m-2 h-1, respectively, ranging from - 19.7 to 98.0 mg m-2 h-1. Cumulative CH4 emissions for LWG ranged from - 0.17 to 0.86 kg m-2 year-1. Global warming potential (GWP, 25.7 kg CO2eq m-2 year-1) was at a high level, which means that the LWG was a source of CH4 emissions. Significant temporal variations on the 4 timescales were observed. And the asymmetry of measurement uncertainty of CH4 flux increases with the timescale. Although the total mean CH4 flux measured by the portable chamber method was 42.1% lower than that of the static chamber method, the temporal variation trends of CH4 flux were similar. The uncertainty of CH4 flux measured in portable chamber was more symmetrical than that in static chamber. These results suggest that the portable chamber method has considerable value as a long-term measurement method for CH4 flux temporal variations.
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Affiliation(s)
- Ru Xue
- College of Environmental Sciences, Sichuan Agricultural University, Chengdu, 611130, China
| | - Xiaoling Liu
- Department of Information Engineering, Sichuan Water Conservancy Vocational College, Yangma Town, Chengdu, 611231, China
| | - Xiaoying Fu
- State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, 610065, China
| | - Hongbing Luo
- College of Environmental Sciences, Sichuan Agricultural University, Chengdu, 611130, China.
- Department of Municipal Engineering, College of Civil Engineering, Sichuan Agricultural University, Chengdu, 611830, China.
- Sichuan Higher Education Engineering Research Center for Disaster Prevention and Mitigation of Village Construction, Sichuan Agricultural University, Dujiangyan, Chengdu, 611830, China.
| | - Ke Zhang
- Department of Municipal Engineering, College of Civil Engineering, Sichuan Agricultural University, Chengdu, 611830, China
- Sichuan Higher Education Engineering Research Center for Disaster Prevention and Mitigation of Village Construction, Sichuan Agricultural University, Dujiangyan, Chengdu, 611830, China
| | - Bruce C Anderson
- Department of Civil Engineering, Queen's University, Kingston, ON, K7L 3N6, Canada
| | - Mei Li
- School of Urban and Rural Construction, Chengdu University, Chengdu, 610106, China
| | - Bo Huang
- Dujiangyan Campus Sichuan Agricultural University, Chengdu, 611830, China
| | - Lijuan Yu
- Dujiangyan Campus Sichuan Agricultural University, Chengdu, 611830, China
| | - Xiaoting Li
- College of Chemistry and Material Science, Sichuan Normal University, Chengdu, 610066, China
| | - Shuzhi Fu
- Dujiangyan Campus Sichuan Agricultural University, Chengdu, 611830, China
| | - Aiping Pu
- Southwest Investment & Development Company Co., Ltd., CSCEC 7th Division, Chengdu, 610095, China
| | - Liangqian Fan
- Department of Municipal Engineering, College of Civil Engineering, Sichuan Agricultural University, Chengdu, 611830, China
- Sichuan Higher Education Engineering Research Center for Disaster Prevention and Mitigation of Village Construction, Sichuan Agricultural University, Dujiangyan, Chengdu, 611830, China
| | - Wei Chen
- Department of Municipal Engineering, College of Civil Engineering, Sichuan Agricultural University, Chengdu, 611830, China
- Sichuan Higher Education Engineering Research Center for Disaster Prevention and Mitigation of Village Construction, Sichuan Agricultural University, Dujiangyan, Chengdu, 611830, China
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Water–Air Interface Greenhouse Gas Emissions (CO2, CH4, and N2O) Emissions Were Amplified by Continuous Dams in an Urban River in Qinghai–Tibet Plateau, China. WATER 2020. [DOI: 10.3390/w12030759] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Continuous dams may lead to great variation in greenhouse gas (GHG) emissions from rivers, which contribute more uncertainty to regional carbon balance. This study is among the first to determine water–air interface GHGs (CO2, CH4, and N2O) in a river with continuous dams in plateau city. Combined static-chamber gas and meteorological chromatography were utilized to monitor the GHGs emission flux at the water–air interface within four continuous dams in the Huoshaogou River in the Qinghai–Tibet Plateau, China. A variation coefficient (VC) and amplification coefficient (AC) were designed to detect the influence of continuous dams on GHG emissions. Results indicate that (1) cascade dams presented an amplifying effect on GHGs emissions from the water-air interface. The VCs of three types of GHGs are 3.7–6.7 times higher than those of the undammed area. The ACs of three types of GHGs are 2.7–4.1 times larger than environmental factors; (2) the average GHG emission fluxes in some dams are higher than that of the first dam, indicating that an amplifying effect may have been accumulated by some continuous dams; (3) EC, pH, Twater, Tair and TDS are found to be principle influencing factors of GHG emission and light intensity, Twater, TOC (plant), TN (sediment) and TOC (sediment) are found to be associated with accumulative changes in GHG emission.
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Zhang S, Liu F, Xiao R, Li Y, Zhou J, Wu J. Emissions of NO and N2O in wetland microcosms for swine wastewater treatment. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:19933-19939. [PMID: 26289333 DOI: 10.1007/s11356-015-5210-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2015] [Accepted: 08/10/2015] [Indexed: 06/04/2023]
Abstract
Nitric oxide (NO) and nitrous oxide (N2O) emitted from wetland systems contribute an important proportion to the global warming effect. In this study, four wetland microcosms vegetated with Myriophyllum elatinoides (WM), Alternanthera philoxeroides (WA), Eichhornia crassipes (WE), or without vegetation (NW) were compared to investigate the emissions of NO and N2O during nitrogen (N) removal process when treating swine wastewater. After 30-day incubation, TN removal rates of 96.4, 74.2, 97.2, and 47.3 % were observed for the WM, WA, WE, and NW microcosms, respectively. Yet, no significant difference was observed in WM and WE (p > 0.05). The average NO and N2O emissions in WE was significantly higher than those in WM, WA, and NW (p < 0.05). In addition, the emission of N2O in WE accounted for 2.10 % of initial TN load and 2.17 % of the total amount of TN removal, compared with less than 1 % in the other microcosms. These findings indicate that wetland vegetated with M. elatinoides may be an optimal system for swine wastewater treatment, based on its higher removal of N and lower emissions of NO and N2O.
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Affiliation(s)
- Shunan Zhang
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan, 410125, China
- Changsha Research Station for Agricultural and Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan, 410125, China
- Graduate University of Chinese Academy of Sciences, Beijing, 100039, China
| | - Feng Liu
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan, 410125, China.
- Changsha Research Station for Agricultural and Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan, 410125, China.
| | - Runlin Xiao
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan, 410125, China
- Changsha Research Station for Agricultural and Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan, 410125, China
| | - Yong Li
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan, 410125, China
- Changsha Research Station for Agricultural and Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan, 410125, China
| | - Juan Zhou
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan, 410125, China
- Changsha Research Station for Agricultural and Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan, 410125, China
- Graduate University of Chinese Academy of Sciences, Beijing, 100039, China
| | - Jinshui Wu
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan, 410125, China.
- Changsha Research Station for Agricultural and Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan, 410125, China.
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Barbera AC, Borin M, Cirelli GL, Toscano A, Maucieri C. Comparison of carbon balance in Mediterranean pilot constructed wetlands vegetated with different C4 plant species. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:2372-2383. [PMID: 24743957 DOI: 10.1007/s11356-014-2870-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Accepted: 04/02/2014] [Indexed: 06/03/2023]
Abstract
This study investigates carbon dioxide (CO2) and methane (CH4) emissions and carbon (C) budgets in a horizontal subsurface flow pilot-plant constructed wetland (CW) with beds vegetated with Cyperus papyrus L., Chrysopogon zizanioides (L.) Roberty, and Mischantus × giganteus Greef et Deu in the Mediterranean basin (Sicily) during the 1st year of plant growing season. At the end of the vegetative season, M. giganteus showed the higher biomass accumulation (7.4 kg m(-2)) followed by C. zizanioides (5.3 kg m(-2)) and C. papyrus (1.8 kg m(-2)). Significantly higher emissions of CO2 were detected in the summer, while CH4 emissions were maximum during spring. Cumulative CO2 emissions by C. papyrus and C. zizanioides during the monitoring period showed similar trends with final values of about 775 and 1,074 g m(-2), respectively, whereas M. giganteus emitted 3,395 g m(-2). Cumulative CH4 bed emission showed different trends for the three C4 plant species in which total gas release during the study period was for C. papyrus 12.0 g m(-2) and ten times higher for M. giganteus, while C. zizanioides bed showed the greatest CH4 cumulative emission with 240.3 g m(-2). The wastewater organic carbon abatement determined different C flux in the atmosphere. Gas fluxes were influenced both by plant species and monitored months with an average C-emitted-to-C-removed ratio for C. zizanioides, C. papyrus, and M. giganteus of 0.3, 0.5, and 0.9, respectively. The growing season C balances were positive for all vegetated beds with the highest C sequestered in the bed with M. giganteus (4.26 kg m(-2)) followed by C. zizanioides (3.78 kg m(-2)) and C. papyrus (1.89 kg m(-2)). To our knowledge, this is the first paper that presents preliminary results on CO2 and CH4 emissions from CWs vegetated with C4 plant species in Mediterranean basin during vegetative growth.
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Affiliation(s)
- Antonio C Barbera
- Department of Agriculture and Food Science, DISPA, University of Catania, Via Valdisavoia, 5-95123, Catania, Italy
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VanderZaag AC, Gordon RJ, Burton DL, Jamieson RC, Stratton GW. Greenhouse gas emissions from surface flow and subsurface flow constructed wetlands treating dairy wastewater. JOURNAL OF ENVIRONMENTAL QUALITY 2010; 39:460-471. [PMID: 20176819 DOI: 10.2134/jeq2009.0166] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Agricultural wastewater treatment is important for protecting water quality in rural ecosystems, and constructed wetlands are an effective treatment option. During treatment, however, some C and N are converted to CH(4), N(2)O, respectively, which are potent greenhouse gases (GHGs). The objective of this study was to assess CH(4), N(2)O, and CO(2) emissions from surface flow (SF) and subsurface flow (SSF) constructed wetlands. Six constructed wetlands (three SF and three SSF; 6.6 m(2) each) were loaded with dairy wastewater in Truro, Nova Scotia, Canada. From August 2005 through September 2006, GHG fluxes were measured continuously using transparent steady-state chambers that encompassed the entire wetlands. Flux densities of all gases were significantly (p < 0.01) different between SF and SSF wetlands changed significantly with time. Overall, SF wetlands had significantly (p < 0.01) higher emissions of CH(4) N(2)O than SSF wetlands and therefore had 180% higher total GHG emissions. The ratio of N(2)O to CH(4) emissions (CO(2)-equivalent) was nearly 1:1 in both wetland types. Emissions of CH(4)-C as a percentage of C removal varied seasonally from 0.2 to 27% were 2 to 3x higher in SF than SSF wetlands. The ratio of N(2)O-N emitted to N removed was between 0.1 and 1.6%, and the difference between wetland types was inconsistent. Thus, N(2)O emissions had a similar contribution to N removal in both wetland types, but SSF wetlands emitted less CH(4) while removing more C from the wastewater than SF wetlands.
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Affiliation(s)
- A C VanderZaag
- Process Engineering and Applied Science, Dalhousie Univ., Halifax, NS, Canada B3J 2X4.
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Truu M, Juhanson J, Truu J. Microbial biomass, activity and community composition in constructed wetlands. THE SCIENCE OF THE TOTAL ENVIRONMENT 2009; 407:3958-3971. [PMID: 19157517 DOI: 10.1016/j.scitotenv.2008.11.036] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2008] [Revised: 11/05/2008] [Accepted: 11/14/2008] [Indexed: 05/27/2023]
Abstract
The aim of the current article is to give an overview about microbial communities and their functioning but also about factors affecting microbial activity in the three most common types (surface flow and two types of sub-surface flow) of constructed wetlands. The paper reviews the community composition and structural diversity of the microbial biomass, analyzing different aspects of microbial activity with respect to wastewater properties, specific wetland type, and environmental parameters. A brief introduction about the application of different novel molecular techniques for the assessment of microbial communities in constructed wetlands is also given. Microbially mediated processes in constructed wetlands are mainly dependent on hydraulic conditions, wastewater properties, including substrate and nutrient quality and availability, filter material or soil type, plants, and different environmental factors. Microbial biomass is within similar ranges in both horizontal and vertical subsurface flow and surface flow constructed wetlands. Stratification of the biomass but also a stratified structural pattern of the bacterial community can be seen in subsurface flow systems. Microbial biomass C/N ratio is higher in horizontal flow systems compared to vertical flow systems, indicating the structural differences in microbial communities between those two constructed wetland types. The total activity of the microbial community is in the same range, but heterotrophic growth is higher in the subsurface (vertical flow) system compared to the surface flow systems. Available species-specific data about microbial communities in different types of wetlands is scarce and therefore it is impossible make any general conclusions about the dynamics of microbial community structure in wetlands, its relationship to removal processes and operational parameters.
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Affiliation(s)
- Marika Truu
- Institute of Molecular and Cell Biology, Faculty of Science and Technology, University of Tartu, 23 Riia Str, Tartu, Estonia
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Kuschk P, Wiessner A, Kästner M, Müller R, Münch C, Paredes D. Pflanzenkläranlagen - Zukunftspotenzial und Forschungsbedarf. CHEM-ING-TECH 2008. [DOI: 10.1002/cite.200800085] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Mander U, Lõhmus K, Teiter S, Mauring T, Nurk K, Augustin J. Gaseous fluxes in the nitrogen and carbon budgets of subsurface flow constructed wetlands. THE SCIENCE OF THE TOTAL ENVIRONMENT 2008; 404:343-353. [PMID: 18486194 DOI: 10.1016/j.scitotenv.2008.03.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
In 2001 and 2002, fluxes of N(2)O, CH(4), CO(2) and N(2) were measured in two constructed wetlands (CW) for domestic wastewater treatment in Estonia. The difference between the median values of N(2)O, CH(4), and N(2) fluxes in the horizontal subsurface flow (HSSF) CWs was non-significant, being 1.3-1.4 and 1.4-4.1 mg m(-2) d(-1) for N(2)O-N and CH(4)-C, and 0.16-0.17 g N m(-2) d(-1) for N(2)-N respectively. The CO(2)-C flux was significantly lower (0.6 g C m(-2) d(-1)) in one of the HSSF filters of a hybrid CW, whereas the single HSSF and VSSF filters emitted 1.7 and 2.0 g C m(-2) d(-1). The median value of CH(4)-C emission in CWs varied from 1.4 to 42.6 g C m(-2) d(-1), being significantly higher in the VSSF filter beds. We also estimated C and N budgets in one of the HSSF CWs (312.5 m(2)) for 2001 and 2002. The total C input into this system was similar in 2001 and 2002, 772 and 719 kg C year(-1), but was differently distributed between constituent fluxes. In 2001, the main input flux was soil and microbial accumulation (663 kg C year(-1) or 85.8% of total C input), followed by plant net primary production (NPP) (10.2%) and wastewater inflow (3.9%). In 2002, 55.7% of annual C input was bound in plant NPP, whereas the increase in soil C formed 28.5% and wastewater inflow 15.7%. The main C output flux was soil respiration, including microbial respiration from soil and litter, and the respiration of roots and rhizomes. It formed 120 (97.5%) and 230 kg C year(-1) (98.2%) in 2001 and 2002 respectively. The measured CH(4)-C flux remained below 0.1% of total C output. The HSSF CW was generally found to be a strong C sink, and its annual C sequestration was 649 and 484 kg C year(-1) per wetland in 2001 and 2002 respectively. However, negative soil and microbial accumulation values in recent years indicate decreasing C sequestration. The average annual N removal from the system was 38-59 kg N year(-1) (46-48% of the initial total N loading). The most important flux of the N budget was N(2)-N emission (22.7 kg in 2001 and 15.2 kg in 2002), followed by plant belowground assimilation (2.3 and 11.9 kg N year(-1) in 2001 and 2002), and above-ground assimilation (1.9 and 9.2 kg N year(-1), respectively). N(2)O emission was low: 0.37-0.60 kg N year(-1)(.).
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Affiliation(s)
- Ulo Mander
- Department of Geography, Institute of Ecology and Earth Sciences, University of Tartu, Vanemuise 46, Tartu, Estonia.
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Søvik AK, Kløve B. Emission of N2O and CH4 from a constructed wetland in southeastern Norway. THE SCIENCE OF THE TOTAL ENVIRONMENT 2007; 380:28-37. [PMID: 17204306 DOI: 10.1016/j.scitotenv.2006.10.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2005] [Revised: 09/29/2006] [Accepted: 10/06/2006] [Indexed: 05/13/2023]
Abstract
The Skjønhaug constructed wetland (CW) is a free surface water (FSW) wetland polishing chemically treated municipal wastewater in southeastern Norway and consists of three ponds as well as trickling, unsaturated filters with light weight aggregates (LWA). Fluxes of nitrous oxide (N(2)O) and methane (CH(4)) have been measured during the autumn, winter and summer from all three ponds as well as from the unsaturated filters. Physicochemical parameters of the water have been measured at the same localities. The large temporal and spatial variation of N(2)O fluxes was found to cover a range of -0.49 to 110 mg N(2)O-N m(-2) day(-1), while the fluxes of CH(4) was found to cover a range of -1.2 to 1900 mg m(-2) day(-1). Thus, both emission and consumption occurred. Regarding fluxes of N(2)O there was a significant difference between the summer, winter and autumn, with the highest emissions occurring during the autumn. The fluxes of CH(4) were, on the other hand, not significantly different with regard to seasons. Both the emissions of N(2)O and CH(4) were positively influenced by the amount of total organic carbon (TOC). The measured fluxes of N(2)O and CH(4) are in the same range as those reported from other CWs treating wastewater. There was an approximately equal contribution to the global warming potential from N(2)O and CH(4).
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Affiliation(s)
- A K Søvik
- Norwegian Institute for Agricultural and Environmental Research - Soil and Environment Division (Bioforsk), Frederik A. Dahls vei 20, 1432 As, Norway.
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Søvik AK, Augustin J, Heikkinen K, Huttunen JT, Necki JM, Karjalainen SM, Kløve B, Liikanen A, Mander U, Puustinen M, Teiter S, Wachniew P. Emission of the greenhouse gases nitrous oxide and methane from constructed wetlands in europe. JOURNAL OF ENVIRONMENTAL QUALITY 2006; 35:2360-73. [PMID: 17071907 DOI: 10.2134/jeq2006.0038] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The potential atmospheric impact of constructed wetlands (CWs) should be examined as there is a worldwide increase in the development of these systems. Fluxes of N(2)O, CH(4), and CO(2) have been measured from CWs in Estonia, Finland, Norway, and Poland during winter and summer in horizontal and vertical subsurface flow (HSSF and VSSF), free surface water (FSW), and overland and groundwater flow (OGF) wetlands. The fluxes of N(2)O-N, CH(4)-C, and CO(2)-C ranged from -2.1 to 1000, -32 to 38 000, and -840 to 93 000 mg m(-2) d(-1), respectively. Emissions of N(2)O and CH(4) were significantly higher during summer than during winter. The VSSF wetlands had the highest fluxes of N(2)O during both summer and winter. Methane emissions were highest from the FSW wetlands during wintertime. In the HSSF wetlands, the emissions of N(2)O and CH(4) were in general highest in the inlet section. The vegetated ponds in the FSW wetlands released more N(2)O than the nonvegetated ponds. The global warming potential (GWP), summarizing the mean N(2)O and CH(4) emissions, ranged from 5700 to 26000 and 830 to 5100 mg CO(2) equivalents m(-2) d(-1) for the four CW types in summer and winter, respectively. The wintertime GWP was 8.5 to 89.5% of the corresponding summertime GWP, which highlights the importance of the cold season in the annual greenhouse gas release from north temperate and boreal CWs. However, due to their generally small area North European CWs were suggested to represent only a minor source for atmospheric N(2)O and CH(4).
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Affiliation(s)
- A K Søvik
- Bioforsk-Norwegian Institute for Agricultural and Environmental Research-Soil and Environment Division, Frederik A. Dahls vei 20, 1432 As, Norway.
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