DOI: 10.1111/gcb.13345
论文题名: Microbial community dynamics in soil aggregates shape biogeochemical gas fluxes from soil profiles – upscaling an aggregate biophysical model
作者: Ebrahimi A. ; Or D.
刊名: Global Change Biology
ISSN: 13541013
出版年: 2016
卷: 22, 期: 9 起始页码: 3141
结束页码: 3156
语种: 英语
英文关键词: biogeochemical fluxes
; denitrification
; hydration
; individual-based model
; microbial community
; pore network modeling
; soil aggregates
; soil stracture
Scopus关键词: biogeochemical cycle
; community composition
; community dynamics
; denitrification
; hydration
; individual-based model
; microbial activity
; microbial community
; soil aggregate
; soil microorganism
; soil profile
; soil structure
英文摘要: Microbial communities inhabiting soil aggregates dynamically adjust their activity and composition in response to variations in hydration and other external conditions. These rapid dynamics shape signatures of biogeochemical activity and gas fluxes emitted from soil profiles. Recent mechanistic models of microbial processes in unsaturated aggregate-like pore networks revealed a highly dynamic interplay between oxic and anoxic microsites jointly shaped by hydration conditions and by aerobic and anaerobic microbial community abundance and self-organization. The spatial extent of anoxic niches (hotspots) flicker in time (hot moments) and support substantial anaerobic microbial activity even in aerated soil profiles. We employed an individual-based model for microbial community life in soil aggregate assemblies represented by 3D angular pore networks. Model aggregates of different sizes were subjected to variable water, carbon and oxygen contents that varied with soil depth as boundary conditions. The study integrates microbial activity within aggregates of different sizes and soil depth to obtain estimates of biogeochemical fluxes from the soil profile. The results quantify impacts of dynamic shifts in microbial community composition on CO2 and N2O production rates in soil profiles in good agreement with experimental data. Aggregate size distribution and the shape of resource profiles in a soil determine how hydration dynamics shape denitrification and carbon utilization rates. Results from the mechanistic model for microbial activity in aggregates of different sizes were used to derive parameters for analytical representation of soil biogeochemical processes across large scales of practical interest for hydrological and climate models. © 2016 John Wiley & Sons Ltd 资助项目: Data supporting the obtained results are available upon request from corresponding author (email: ali.ebrahimi@usys.ethz.ch). The financial support of the European Research Council (ERC) Advanced Grant (320499 – SoilLife) and by SystemsX.ch (MicroScapesX project) are gratefully acknowledged.
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/61302
Appears in Collections: 影响、适应和脆弱性
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作者单位: Department of Environmental Systems Science, ETH Zürich, Zürich, Switzerland
Recommended Citation:
Ebrahimi A.,Or D.. Microbial community dynamics in soil aggregates shape biogeochemical gas fluxes from soil profiles – upscaling an aggregate biophysical model[J]. Global Change Biology,2016-01-01,22(9)