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Yin Y, Kara-Murdoch F, Murdoch RW, Yan J, Chen G, Xie Y, Sun Y, Löffler FE. Nitrous oxide inhibition of methanogenesis represents an underappreciated greenhouse gas emission feedback. THE ISME JOURNAL 2024; 18:wrae027. [PMID: 38447133 PMCID: PMC10960958 DOI: 10.1093/ismejo/wrae027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 02/13/2024] [Accepted: 02/14/2024] [Indexed: 03/08/2024]
Abstract
Methane (CH4) and nitrous oxide (N2O) are major greenhouse gases that are predominantly generated by microbial activities in anoxic environments. N2O inhibition of methanogenesis has been reported, but comprehensive efforts to obtain kinetic information are lacking. Using the model methanogen Methanosarcina barkeri strain Fusaro and digester sludge-derived methanogenic enrichment cultures, we conducted growth yield and kinetic measurements and showed that micromolar concentrations of N2O suppress the growth of methanogens and CH4 production from major methanogenic substrate classes. Acetoclastic methanogenesis, estimated to account for two-thirds of the annual 1 billion metric tons of biogenic CH4, was most sensitive to N2O, with inhibitory constants (KI) in the range of 18-25 μM, followed by hydrogenotrophic (KI, 60-90 μM) and methylotrophic (KI, 110-130 μM) methanogenesis. Dissolved N2O concentrations exceeding these KI values are not uncommon in managed (i.e. fertilized soils and wastewater treatment plants) and unmanaged ecosystems. Future greenhouse gas emissions remain uncertain, particularly from critical zone environments (e.g. thawing permafrost) with large amounts of stored nitrogenous and carbonaceous materials that are experiencing unprecedented warming. Incorporating relevant feedback effects, such as the significant N2O inhibition on methanogenesis, can refine climate models and improve predictive capabilities.
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Affiliation(s)
- Yongchao Yin
- Center for Environmental Biotechnology, University of Tennessee, Knoxville, TN 37996, United States
- Department of Microbiology, University of Tennessee, Knoxville, TN 37996, United States
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States
| | - Fadime Kara-Murdoch
- Center for Environmental Biotechnology, University of Tennessee, Knoxville, TN 37996, United States
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States
| | - Robert W Murdoch
- Center for Environmental Biotechnology, University of Tennessee, Knoxville, TN 37996, United States
| | - Jun Yan
- Center for Environmental Biotechnology, University of Tennessee, Knoxville, TN 37996, United States
- Department of Microbiology, University of Tennessee, Knoxville, TN 37996, United States
- Key Laboratory of Pollution Control and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, Liaoning 110016, China
| | - Gao Chen
- Center for Environmental Biotechnology, University of Tennessee, Knoxville, TN 37996, United States
- Department of Civil and Environmental Engineering, University of Tennessee, Knoxville, TN 37996, United States
| | - Yongchao Xie
- Center for Environmental Biotechnology, University of Tennessee, Knoxville, TN 37996, United States
- Department of Civil and Environmental Engineering, University of Tennessee, Knoxville, TN 37996, United States
| | - Yanchen Sun
- Center for Environmental Biotechnology, University of Tennessee, Knoxville, TN 37996, United States
- Department of Civil and Environmental Engineering, University of Tennessee, Knoxville, TN 37996, United States
| | - Frank E Löffler
- Center for Environmental Biotechnology, University of Tennessee, Knoxville, TN 37996, United States
- Department of Microbiology, University of Tennessee, Knoxville, TN 37996, United States
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States
- Department of Civil and Environmental Engineering, University of Tennessee, Knoxville, TN 37996, United States
- Department of Biosystems Engineering and Soil Science, University of Tennessee, Knoxville, TN 37996, United States
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Zhang W, Tao X, Hu Z, Kang E, Yan Z, Zhang X, Wang J. The driving effects of nitrogen deposition on nitrous oxide and associated gene abundances at two water table levels in an alpine peatland. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 898:165525. [PMID: 37451456 DOI: 10.1016/j.scitotenv.2023.165525] [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: 12/21/2022] [Revised: 07/04/2023] [Accepted: 07/11/2023] [Indexed: 07/18/2023]
Abstract
Alpine peatlands are recognized as a weak or negligible source of nitrous oxide (N2O). Anthropogenic activities and climate change resulted in the altered water table (WT) levels and increased nitrogen (N) deposition, which could potentially transition this habitat into a N2O emission hotspot. However, the underlying mechanism related with the effects is still uncertain. Hence, we conducted a mesocosm experiment to address the response of growing-season N2O emissions and the gene abundances of nitrification (bacterial amoA) and denitrification (narG, nirS, norB and nosZ) to the increased N deposition (20 kg N ha-1 yr-1) at two WT levels (WT-30, 30 cm below soil surface; WT10, 10 cm above soil surface) in the Zoige alpine peatland, Qinghai-Tibetan Plateau. The results showed that the WT did not affect N2O emissions, and this was attributed with the limitation of soil NO3-. The higher WT level increased denitrification (narG and nirS gene abundance) resulting in the depletion of soil NO3-, but the consequent NO3- deficiency further limited denitrification, while the WT did not affect nitrification (bacterial amoA gene abundance). Meanwhile, the N deposition increased N2O emissions, regardless of WT levels. This was associated with the N-deposition induced increase in denitrification-related gene abundances of narG, nirS, norB and nosZ at WT-30 and narG at WT10. Additionally, the N2O emission factor assigned to N deposition was 1.3 % at WT-30 and 0.9 % at WT10, respectively. Our study provided comprehensive understanding of the mechanisms referring N2O emissions in response to the interactions between climate change and human disturbance from this high-altitude peatland.
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Affiliation(s)
- Wantong Zhang
- Institute of Wetland Research, Chinese Academy of Forestry, Beijing Key Laboratory of Wetland Services and Restoration, Beijing 100091, China; Insititute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu 610218, China; Sino-Danish Centre for Education and Research, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiuping Tao
- Insititute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu 610218, China
| | - Zhengyi Hu
- Sino-Danish Centre for Education and Research, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Enze Kang
- Institute of Wetland Research, Chinese Academy of Forestry, Beijing Key Laboratory of Wetland Services and Restoration, Beijing 100091, China
| | - Zhongqing Yan
- Institute of Wetland Research, Chinese Academy of Forestry, Beijing Key Laboratory of Wetland Services and Restoration, Beijing 100091, China; Sichuan Zoige Wetland Ecosystem Research Station, Tibetan Autonomous Prefecture of Aba 624500, China
| | - Xiaodong Zhang
- Institute of Wetland Research, Chinese Academy of Forestry, Beijing Key Laboratory of Wetland Services and Restoration, Beijing 100091, China; Sichuan Zoige Wetland Ecosystem Research Station, Tibetan Autonomous Prefecture of Aba 624500, China
| | - Jinzhi Wang
- Institute of Wetland Research, Chinese Academy of Forestry, Beijing Key Laboratory of Wetland Services and Restoration, Beijing 100091, China; Sichuan Zoige Wetland Ecosystem Research Station, Tibetan Autonomous Prefecture of Aba 624500, China.
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Ma G, Wang X, Sun X, Wang S, Du Y, Jiang J. Effects of warming and litter positions on litter decomposition in a boreal peatland. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.1078104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Litter decomposition is an important source of carbon accumulation in the permafrost peatlands. Climate warming has led to shrub expansions and accelerated litter mixing with soils and fluctuations in the water table. However, little is known about how changes in the position of the litter will affect litter decomposition under climate warming. To reveal the mechanisms of response of the location of litter in the soil and climate warming to litter decomposition in permafrost peatlands. Here, we selected the evergreen shrub, Chamaedaphne calyculata, and the deciduous shrub, Vaccinium uliginosum, from the permafrost peatlands of the Greater Hing’an Mountains, China. The leaf litter was placed on the soil surface (no-mixing) and mixed with the soil (soil-litter mixing), and then it was incubated for 124 days at 15°C (control) and 20°C (warming). Our results showed that warming significantly increased the CO2 emission rates of C. calyculata and V. uliginosum by 19.9 and 17.4%, respectively. When compared to no-mixing, the CO2 emission rates were reduced (not significantly) by 1.5 (C. calyculata) and increased 13.6% (V. uliginosum) with soil-litter mixing. Interestingly, soil-litter mixing suppressed the positive effect of warming on the CO2 emission rates relative to no-mixing, and the suppressing effects in the V. uliginosum subplot were stronger than those in the C. calyculata subplot. Specifically, warming significantly increased the CO2 emissions of C. calyculata by 27.4% under no-mixing but the increase decreased to 13.1% under soil-litter mixing. Similarly, warming induced significant increases in the CO2 emissions of V. uliginosum, with an increase of 38.8% under no-mixing but non-significant increases (1.9%) were observed under soil-litter mixing. The combination of the enzyme activities of β-1,4-glucosidase, β-1,4-xylosidase and β-D-1,4-cellobiosidase and laccase and phenolics explained more than 60.0% of the variability in the CO2 emissions of C. calyculata and V. uliginosum, respectively. Our study highlights the importance of litter positions in mediating the responses of litter decomposition to climate warming and shrub expansions in the northern peatlands.
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Wu Y, Xu X, McCarter CPR, Zhang N, Ganzoury MA, Waddington JM, de Lannoy CF. Assessing leached TOC, nutrients and phenols from peatland soils after lab-simulated wildfires: Implications to source water protection. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 822:153579. [PMID: 35114220 DOI: 10.1016/j.scitotenv.2022.153579] [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: 11/10/2021] [Revised: 01/25/2022] [Accepted: 01/27/2022] [Indexed: 06/14/2023]
Abstract
Pollutant leaching from wildfire-impacted peatland soils (peat) is well-known, but often underestimated when considering boreal ecosystem source water protection and when treating source waters to provide clean drinking water. Burning peat impacts its physical properties and chemical composition, yet the consequences of these transformations to source water quality through pollutant leaching has not been studied in detail. We combusted near-surface boreal peat under simulated peat smoldering conditions at two temperatures (250 °C and 300 °C) and quantified the concentrations of the leached carbon, nutrients and phenols from 5 g peat L-1 reverse osmosis (RO) water suspensions over a 2-day leaching period. For the conditions studied, measured water quality parameters exceeded US surface water guidelines and even exceeded EU and Canadian wastewater/sewer discharge limits including chemical oxygen demand (COD) (125 mg/L), total nitrogen (TN) (15 mg/L), and total phosphorus (TP) (2 mg/L). Phenols were close to or higher than the suggested water supply standard established by US EPA (1 mg/L). Leached carbon, nitrogen and phosphorus mainly came from the organic fraction of peats. Heating peats to 250 °C promoted the leaching of carbon-related pollutants, whereas heating to 300 °C enhanced the leaching of nutrients. Post-heated peats leached higher loads of pollutants in water than pre-heated peats, suggesting that fire-damaged boreal peats may be a critical but underappreciated source of water pollution. A simplified Partial Least Squares (PLS) model based on other easily measured parameters provided a simple method for determining the extent of COD and phenolic pollution in bulk water, relevant for water and wastewater treatment plants. Conclusions from this lab study indicate the need for field measurements of aquatic pollutants downstream of peatland watersheds post-fire as well as increased monitoring and treatment of potable water sources for leachable micropollutants in fire-dominated forested peatlands.
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Affiliation(s)
- Yichen Wu
- Department of Chemical Engineering, McMaster University, Hamilton, ON L8S 4L7, Canada
| | - Xuebin Xu
- State Key Laboratory of Soil and Sustainable Agriculture, Chinese Academy of Sciences, Institute of Soil Science, Nanjing, 210008, China
| | - Colin P R McCarter
- School of Earth, Environment & Society, McMaster University, Hamilton, ON L8S 4L7, Canada
| | - Nan Zhang
- Department of Chemical Engineering, McMaster University, Hamilton, ON L8S 4L7, Canada
| | - Mohamed A Ganzoury
- Department of Chemical Engineering, McMaster University, Hamilton, ON L8S 4L7, Canada
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Le TB, Wu J, Gong Y. Vascular plants regulate responses of boreal peatland Sphagnum to climate warming and nitrogen addition. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 819:152077. [PMID: 34856288 DOI: 10.1016/j.scitotenv.2021.152077] [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: 09/16/2021] [Revised: 11/25/2021] [Accepted: 11/26/2021] [Indexed: 06/13/2023]
Abstract
Boreal peatland Sphagnum may be affected by climate warming and elevated nitrogen availability directly and indirectly via altering vascular plant interaction. Here, we used a field experiment of nitrogen addition, warming, and vascular plant removal to investigate the effects of these factors on Sphagnum in a Canadian blanket boreal peatland. We revealed that significant effects of warming and nitrogen addition on Sphagnum were regulated by vascular plant interaction. The intense competition of vascular plants accelerated an adverse effect of warming on Sphagnum, while facilitation of vascular plants reduced detrimental losses of the Sphagnum due to high dose of nitrogen addition and both warming and the nitrogen addition. These findings indicate the crucial role of vascular plants in regulating the effects of environmental changes on existing Sphagnum in boreal peatlands.
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Affiliation(s)
- Thuong Ba Le
- Environment and Sustainability, School of Science and the Environment, Memorial University of Newfoundland, Corner Brook, NL A2H 5G4, Canada; Graduate Program in Environmental Science, Memorial University of Newfoundland, St. John's, NL, Canada; Vietnam National University of Forestry, Hanoi, Viet Nam
| | - Jianghua Wu
- Environment and Sustainability, School of Science and the Environment, Memorial University of Newfoundland, Corner Brook, NL A2H 5G4, Canada; Graduate Program in Environmental Science, Memorial University of Newfoundland, St. John's, NL, Canada.
| | - Yu Gong
- Environment and Sustainability, School of Science and the Environment, Memorial University of Newfoundland, Corner Brook, NL A2H 5G4, Canada; Graduate Program in Environmental Science, Memorial University of Newfoundland, St. John's, NL, Canada
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Gong Y, Wu J. Vegetation composition modulates the interaction of climate warming and elevated nitrogen deposition on nitrous oxide flux in a boreal peatland. GLOBAL CHANGE BIOLOGY 2021; 27:5588-5598. [PMID: 34437735 DOI: 10.1111/gcb.15865] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 07/22/2021] [Accepted: 08/08/2021] [Indexed: 06/13/2023]
Abstract
Northern peatlands with large organic nitrogen (N) storage have the potential to be N2 O hotspots under climate warming, elevated N deposition, and vegetation composition change caused by climate change. However, the interactions of these three factors and the primary controls on N2 O fluxes in peatlands are not well-known. Here, the three factors were manipulated in a boreal bog in western Newfoundland, Canada for 5 years. We found that warming mitigated the positive N effect on N2 O fluxes in the mid-growing season under intact vegetation owing to the increase of available N uptake by vegetation and less N for N2 O production. In contrast, warming strengthened the N effect on N2 O fluxes in the early growing season under the absence of graminoids or shrubs, which could be attributed to the increase of available carbon and nitrogen for N2 O production. It should be noted that these effects were not observed under the condition of low carbon availability. In addition, gross primary production was found as a critical control on N2 O fluxes under N addition. Our findings emphasize that the interaction of abiotic (warming and elevated nitrogen deposition) and biotic factors (vegetation composition change) on N2 O fluxes should be taken into account in order to project N2 O fluxes in peatland ecosystems accurately.
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Affiliation(s)
- Yu Gong
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden of the Chinese Academy of Sciences, Wuhan, PR China
- Environment and Sustainability, School of Science and the Environment, Memorial University of Newfoundland, Corner Brook, Newfoundland, Canada
- Graduate Program in Environmental Science, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
| | - Jianghua Wu
- Environment and Sustainability, School of Science and the Environment, Memorial University of Newfoundland, Corner Brook, Newfoundland, Canada
- Graduate Program in Environmental Science, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
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Chen M, Chang L, Zhang J, Guo F, Vymazal J, He Q, Chen Y. Global nitrogen input on wetland ecosystem: The driving mechanism of soil labile carbon and nitrogen on greenhouse gas emissions. ENVIRONMENTAL SCIENCE AND ECOTECHNOLOGY 2020; 4:100063. [PMID: 36157707 PMCID: PMC9488104 DOI: 10.1016/j.ese.2020.100063] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 10/07/2020] [Accepted: 10/08/2020] [Indexed: 05/19/2023]
Abstract
Greenhouse gas emissions from wetlands are significantly promoted by global nitrogen input for changing the rate of soil carbon and nitrogen cycling, and are substantially affected by soil labile carbon and nitrogen conversely. However, the driving mechanism by which soil labile carbon and nitrogen affect greenhouse gas emissions from wetland ecosystems under global nitrogen input is not well understood. Working out the driving factor of nitrogen input on greenhouse gas emissions from wetlands is critical to reducing global warming from nitrogen input. Thus, we synthesized 72 published studies (2144 paired observations) of greenhouse gas fluxes and soil labile compounds of carbon and nitrogen (ammonium, nitrate, dissolved organic carbon, soil microbial biomass nitrogen and carbon), to understand the effects of labile carbon and nitrogen on greenhouse gas emissions under global nitrogen input. Across the data set, nitrogen input significantly promoted carbon dioxide, methane and nitrous oxide emissions from wetlands. In particular, at lower nitrogen rates (<100 kg ha-1·yr-1) and with added ammonium compounds, freshwater wetland significantly promoted carbon dioxide and methane emissions. Peatland was the largest nitrous oxide source under these conditions. This meta-analysis also revealed that nitrogen input stimulated dissolved organic carbon, ammonium, nitrate, microbial biomass carbon and microbial biomass nitrogen accumulation in the wetland ecosystem. The variation-partitioning analysis and structural equation model were used to analyze the relationship between the greenhouse gas and labile carbon and nitrogen further. These results revealed that dissolved organic carbon (DOC) is the primary factor driving greenhouse gas emission from wetlands under global nitrogen input, whereas microbial biomass carbon (MBC) more directly affects greenhouse gas emission than other labile carbon and nitrogen.
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Affiliation(s)
- Mengli Chen
- College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region’s Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China
- Key Laboratory of the Three Gorges Reservoir Region’s Eco-Environment, Ministry of Education, Chongqing, 400045, China
| | - Lian Chang
- College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region’s Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China
- Key Laboratory of the Three Gorges Reservoir Region’s Eco-Environment, Ministry of Education, Chongqing, 400045, China
| | - Junmao Zhang
- College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region’s Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China
- Key Laboratory of the Three Gorges Reservoir Region’s Eco-Environment, Ministry of Education, Chongqing, 400045, China
| | - Fucheng Guo
- College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region’s Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China
- Key Laboratory of the Three Gorges Reservoir Region’s Eco-Environment, Ministry of Education, Chongqing, 400045, China
| | - Jan Vymazal
- Department of Applied Ecology, Faculty of Environmental Sciences, Czech University of Life Sciences Prague, 16521, Prague 6, Czech Republic
| | - Qiang He
- College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region’s Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China
- Key Laboratory of the Three Gorges Reservoir Region’s Eco-Environment, Ministry of Education, Chongqing, 400045, China
| | - Yi Chen
- College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region’s Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China
- Key Laboratory of the Three Gorges Reservoir Region’s Eco-Environment, Ministry of Education, Chongqing, 400045, China
- Corresponding author. College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region’s Eco-Environment, Ministry of education, Chongqing University, Chongqing, 400045, 174 Shazhengjie Street, Shapingba District, China.
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Vogt J, Wu J, Altdorff D, Ba Le T, Gong Y. Nitrous oxide fluxes of a boreal abandoned pasture do not significantly differ from an adjacent natural bog despite distinct environmental conditions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 714:136648. [PMID: 32018951 DOI: 10.1016/j.scitotenv.2020.136648] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 01/09/2020] [Accepted: 01/10/2020] [Indexed: 06/10/2023]
Abstract
Land-use conversion of pristine boreal peatlands for agricultural purposes is an ongoing process and projected to become more intensive with rising population growth and increased demands for food production. However, agricultural use of peatlands affects the production and emission of nitrous oxide (N2O), a very potent greenhouse gas currently gaining more attention in the global assessment of greenhouse gases. While the intensity of N2O emissions depends on a range of environmental factors, including hydrological parameters, temperature and the availability of nitrogen in soils, key driving processes remain poorly understood. In order to understand the effects of land-use change on the peatland ecosystem, we quantified N2O fluxes under different land-use in a comparative study between a natural bog and an adjacent abandoned pasture in Newfoundland, Canada. We conducted in situ gas flux measurements using the static chamber method over five growing seasons. In addition, we measured photosynthetic rates and environmental parameters, namely soil temperature and moisture, water table and concentrations of total nitrogen and dissolved organic carbon in pore waters. According to previous studies, we hypothesized higher N2O emissions from the abandoned pasture due to drainage compared to the natural bog. However, despite significant differences of environmental parameters and photosynthetic rates, we found no significant difference of N2O fluxes between the two sites. We argue that N2O production at the abandoned pasture was inhibited due to exhaustion of plant-available nitrogen as a result of increased gross primary production compared to the natural bog. We conclude that the effect of drainage and fertilization on N2O fluxes during the growing season was superposed by vegetation composition change effects at the abandoned pasture, leading to similar N2O fluxes at both sites.
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Affiliation(s)
- Judith Vogt
- Environment and Sustainability, School of Science and the Environment, Memorial University of Newfoundland, Corner Brook, NL A2H 5G4, Canada; Graduate Program in Environmental Science, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada
| | - Jianghua Wu
- Environment and Sustainability, School of Science and the Environment, Memorial University of Newfoundland, Corner Brook, NL A2H 5G4, Canada; Graduate Program in Environmental Science, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada.
| | - Daniel Altdorff
- School of Science and the Environment, Memorial University of Newfoundland, Corner Brook, NL A2H 5G4, Canada
| | - Thuong Ba Le
- Environment and Sustainability, School of Science and the Environment, Memorial University of Newfoundland, Corner Brook, NL A2H 5G4, Canada; Graduate Program in Environmental Science, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada
| | - Yu Gong
- Environment and Sustainability, School of Science and the Environment, Memorial University of Newfoundland, Corner Brook, NL A2H 5G4, Canada; Graduate Program in Environmental Science, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada
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