DOI: 10.1111/gcb.13296
论文题名: Microbial control of soil organic matter mineralization responses to labile carbon in subarctic climate change treatments
作者: Rousk K. ; Michelsen A. ; Rousk J.
刊名: Global Change Biology
ISSN: 13541013
出版年: 2016
卷: 22, 期: 12 起始页码: 4150
结束页码: 4161
语种: 英语
英文关键词: bacterial growth
; biogeochemistry
; fungal growth
; microbial ecology
; nitrogen cycling
; nitrogen limitation
; soil carbon sequestration
; the priming effect
Scopus关键词: biogeochemistry
; carbon
; climate change
; climate effect
; microbial activity
; mineralization
; nitrogen cycle
; soil carbon
; soil organic matter
; subarctic region
; Bacteria (microorganisms)
; carbon
; nitrogen
; soil
; chemistry
; climate change
; microbiology
; soil
; Sweden
; temperature
; Carbon
; Climate Change
; Nitrogen
; Soil
; Soil Microbiology
; Sweden
; Temperature
英文摘要: Half the global soil carbon (C) is held in high-latitude systems. Climate change will expose these to warming and a shift towards plant communities with more labile C input. Labile C can also increase the rate of loss of native soil organic matter (SOM); a phenomenon termed ‘priming’. We investigated how warming (+1.1 °C over ambient using open top chambers) and litter addition (90 g m−2 yr−1) treatments in the subarctic influenced the susceptibility of SOM mineralization to priming, and its microbial underpinnings. Labile C appeared to inhibit the mineralization of C from SOM by up to 60% within hours. In contrast, the mineralization of N from SOM was stimulated by up to 300%. These responses occurred rapidly and were unrelated to microbial successional dynamics, suggesting catabolic responses. Considered separately, the labile C inhibited C mineralization is compatible with previously reported findings termed ‘preferential substrate utilization’ or ‘negative apparent priming’, while the stimulated N mineralization responses echo recent reports of ‘real priming’ of SOM mineralization. However, C and N mineralization responses derived from the same SOM source must be interpreted together: This suggested that the microbial SOM-use decreased in magnitude and shifted to components richer in N. This finding highlights that only considering SOM in terms of C may be simplistic, and will not capture all changes in SOM decomposition. The selective mining for N increased in climate change treatments with higher fungal dominance. In conclusion, labile C appeared to trigger catabolic responses of the resident microbial community that shifted the SOM mining to N-rich components; an effect that increased with higher fungal dominance. Extrapolating from these findings, the predicted shrub expansion in the subarctic could result in an altered microbial use of SOM, selectively mining it for N-rich components, and leading to a reduced total SOM-use. © 2016 John Wiley & Sons Ltd 资助项目: We thank the Abisko Scientific Research Station for logistic support. This study was supported by grants from the FP7 Marie Curie Actions – COFUND (Grant id: DFF-1325-00025), the Swedish Research Council (Vetenskapsrådet, grant no 2015-04942), the Swedish Research Council Formas (grant no 942-2015-270) and the Danish National Research Foundation (Center for Permafrost, CENPERM DNRF100).
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/61235
Appears in Collections: 影响、适应和脆弱性
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作者单位: Terrestrial Ecology Section, Department of Biology, University of Copenhagen, Universitetsparken 15, Copenhagen, Denmark; Center for Permafrost (CENPERM), University of Copenhagen, Øster Voldgade 10, Copenhagen, Denmark; Section of Microbial Ecology, Department of Biology, Lund University, Lund, Sweden
Recommended Citation:
Rousk K.,Michelsen A.,Rousk J.. Microbial control of soil organic matter mineralization responses to labile carbon in subarctic climate change treatments[J]. Global Change Biology,2016-01-01,22(12)