DOI: 10.1002/2014GB004951
Scopus记录号: 2-s2.0-85027941546
论文题名: CO2 and CH4 isotope compositions and production pathways in a tropical peatland
作者: Holmes M ; E ; , Chanton J ; P ; , Tfaily M ; M ; , Ogram A
刊名: Global Biogeochemical Cycles
ISSN: 8866236
出版年: 2015
卷: 29, 期: 1 起始页码: 1
结束页码: 18
语种: 英语
英文关键词: carbon dioxide
; isotope
; methane
; peat
; tropical wetland
Scopus关键词: carbon cycle
; carbon dioxide
; climate change
; isotopic composition
; methane
; methanogenesis
; peatland
; porewater
; tropical environment
; wetland
; Bocas del Toro
; Changuinola
; Panama [Central America]
英文摘要: While it is widely recognized that peatlands are important in the global carbon cycle, there is limited information on belowground gas production in tropical peatlands. We measured pore water methane (CH4) and carbon dioxide (CO2) concentrations and δ13C isotopic composition and CH4 and CO2 production rates in peat incubations from the Changuinola wetland in Panama. Our most striking finding was that CH4 was depleted in 13C (-94‰ in pore water and produced at -107‰ in incubated peat) relative to CH4 found in most temperate and northern wetlands, potentially impacting the accuracy of approaches that use carbon isotopes to constrain global mass balance estimates. Fractionation factors between CH4 and CO2 showed that hydrogenotrophic methanogenesis was the dominant CH4 production pathway, with up to 100% of the CH4 produced via this route. Far more CO2 than CH4 (7 to 100X) was measured in pore water, due in part to loss of CH4 through ebullition or oxidation and to the production of CO2 from pathways other than methanogenesis. We analyzed data on 58 wetlands from the literature to determine the dominant factors influencing the relative proportions of CH4 produced by hydrogenotrophic and acetoclastic methanogenesis and found that a combination of environmental parameters including pH, vegetation type, nutrient status, and latitude are correlated to the dominant methanogenic pathway. Methane production pathways in tropical peatlands do not correlate with these variables in the same way as their more northerly counterparts and thus may be differently affected by climate change. © 2014. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/78023
Appears in Collections: 气候变化事实与影响
There are no files associated with this item.
作者单位: Department of Earth, Ocean, and Atmospheric Science, Florida State University, Tallahassee, FL, United States; Pacific Northwest National Laboratory, Richland, WA, United States; Soil and Water Science Department, University of Florida, Gainesville, FL, United States
Recommended Citation:
Holmes M,E,, Chanton J,et al. CO2 and CH4 isotope compositions and production pathways in a tropical peatland[J]. Global Biogeochemical Cycles,2015-01-01,29(1)