DOI: 10.1002/2017JG004076
Scopus记录号: 2-s2.0-85048506223
论文题名: The Path From Litter to Soil: Insights Into Soil C Cycling From Long-Term Input Manipulation and High-Resolution Mass Spectrometry
作者: Reynolds L.L. ; Lajtha K. ; Bowden R.D. ; Tfaily M.M. ; Johnson B.R. ; Bridgham S.D.
刊名: Journal of Geophysical Research: Biogeosciences
ISSN: 21698953
出版年: 2018
卷: 123, 期: 5 起始页码: 1486
结束页码: 1497
语种: 英语
英文关键词: carbon mineralization dynamics
; carbon quality
; Catabolic profile
; density fractionation
; FTICR-MS
; soil carbon pools
Scopus关键词: carbon cycle
; carbon sink
; decomposition
; experimental study
; fractionation
; litter
; long-term change
; mass spectrometry
; microbial activity
; mineralization
; molecular analysis
; soil carbon
; soil ecosystem
; soil organic matter
英文摘要: The path of carbon (C) from plant litter to soil organic matter (SOM) is key to understanding how soil C stocks and microbial decomposition will respond to climate change and whether soil C sinks can be enhanced. Long-term ecosystem-scale litter manipulations and molecular characterization of SOM provide a unique opportunity to explore these issues. We incubated soils from a 20-year litter input experiment for 525 days and asked how litter quantity and source (i.e., roots versus aboveground litter) affected C cycling, microbial function, and the size and molecular composition of C pools. Input exclusion led to a 30% loss of soil C, attributable largely to the nonmineral-associated C fraction, and to declines in soil C decomposition. The absence of roots caused a shift in the microbial catabolic profile, though there was little evidence that root litter was preferentially stabilized. Although C pool size did not change with litter additions, Fourier transform ion cyclotron resonance mass spectrometry analysis of the finest mineral fraction revealed dramatic changes to the chemical composition of carbon. Lipid content increased proportionally with input addition and was subsequently mineralized during incubation, indicating that this fraction was metabolically active. Moreover, nonmetric dimensional scaling showed that both litter treatments and incubation caused the molecular composition of SOM to change. We conclude that the path of C from litter to soil may involve labile pools and root-driven microbial activity associated directly with SOM in the soil mineral matrix otherwise previously hypothesized to be stable. ©2018. 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/114024
Appears in Collections: 气候减缓与适应
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作者单位: Department of Crop and Soil Science, Oregon State University, Corvallis, OR, United States; Department of Environmental Science, Allegheny College, Meadville, PA, United States; Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, United States; Landscape Architecture, University of Oregon, Eugene, OR, United States; Institute for a Sustainable Environment, University of Oregon, Eugene, OR, United States; Institute of Ecology and Evolution, University of Oregon, Eugene, OR, United States
Recommended Citation:
Reynolds L.L.,Lajtha K.,Bowden R.D.,et al. The Path From Litter to Soil: Insights Into Soil C Cycling From Long-Term Input Manipulation and High-Resolution Mass Spectrometry[J]. Journal of Geophysical Research: Biogeosciences,2018-01-01,123(5)