DOI: 10.1002/2017GB005622
Scopus记录号: 2-s2.0-85030567399
论文题名: Evaluating the Classical Versus an Emerging Conceptual Model of Peatland Methane Dynamics
作者: Yang W ; H ; , McNicol G ; , Teh Y ; A ; , Estera-Molina K ; , Wood T ; E ; , Silver W ; L
刊名: Global Biogeochemical Cycles
ISSN: 8866236
出版年: 2017
卷: 31, 期: 9 起始页码: 1435
结束页码: 1453
语种: 英语
英文关键词: gross methane fluxes
; methane oxidation
; methanogenesis
; redox
; Sacramento-San Joaquin Delta
; stable isotope pool dilution
Scopus关键词: concentration (composition)
; conceptual framework
; flux measurement
; greenhouse gas
; methane
; methanogenesis
; methanotrophy
; oxidation
; peatland
; redox conditions
; soil profile
; vertical distribution
; California
; Sacramento-San Joaquin Delta
; United States
英文摘要: Methane (CH4) is a potent greenhouse gas that is both produced and consumed in soils by microbially mediated processes sensitive to soil redox. We evaluated the classical conceptual model of peatland CH4 dynamics—in which the water table position determines the vertical distribution of methanogenesis and methanotrophy—versus an emerging model in which methanogenesis and methanotrophy can both occur throughout the soil profile due to spatially heterogeneous redox and anaerobic CH4 oxidation. We simultaneously measured gross CH4 production and oxidation in situ across a microtopographical gradient in a drained temperate peatland and ex situ along the soil profile, giving us novel insight into the component fluxes of landscape-level net CH4 fluxes. Net CH4 fluxes varied among landforms (p < 0.001), ranging from 180.3 ± 81.2 mg C m−2 d−1 in drainage ditches to −0.7 ± 1.2 mg C m−2 d−1 in the highest landform. Contrary to prediction by the classical conceptual model, variability in methanogenesis alone drove the landscape-level net CH4 flux patterns. Consistent with the emerging model, freshly collected soils from above the water table produced CH4 within anaerobic microsites. Even in soil from beneath the water table, gross CH4 production was best predicted by the methanogenic fraction of carbon mineralization, an index of highly reducing microsites. We measured low rates of anaerobic CH4 oxidation, which may have been limited by relatively low in situ CH4 concentrations in the hummock/hollow soil profile. Our study revealed complex CH4 dynamics better represented by the emerging heterogeneous conceptual model than the classical model based on redox strata. ©2017. 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/77703
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 Plant Biology and Department of Geology, University of Illinois at Urbana-Champaign, Urbana, IL, United States; Ecosystem Sciences Division, Department of Environmental Science, Policy, and Management, University of California, Berkeley, CA, United States; Department of Natural Science, University of Alaska Southeast, Juneau, AK, United States; Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, United Kingdom; USDA Forest Service, International Institute of Tropical Forestry, Rio Piedras, Puerto Rico
Recommended Citation:
Yang W,H,, McNicol G,et al. Evaluating the Classical Versus an Emerging Conceptual Model of Peatland Methane Dynamics[J]. Global Biogeochemical Cycles,2017-01-01,31(9)