DOI: 10.1029/2018GB006077
论文题名: A Mechanistic Model of Microbially Mediated Soil Biogeochemical Processes: A Reality Check
作者: Fatichi S. ; Manzoni S. ; Or D. ; Paschalis A.
刊名: Global Biogeochemical Cycles
ISSN: 0886-6236
EISSN: 1944-9224
出版年: 2019
卷: 33, 期: 6 语种: 英语
英文关键词: biogeochemistry
; biomineralization
; carbon cycle
; decomposition
; experimental study
; exudation
; litter
; microbial activity
; microbial community
; organic carbon
; soil microorganism
; soil organic matter
; soil respiration
; Fungi
学科: manipulation experiments
; microbes
; modeling
; soil carbon cycle
; soil respiration
; terrestrial ecosystems
中文摘要: Present gaps in the representation of key soil biogeochemical processes such as the partitioning of soil organic carbon among functional components, microbial biomass and diversity, and the coupling of carbon and nutrient cycles present a challenge to improving the reliability of projected soil carbon dynamics. We introduce a new soil biogeochemistry module linked with a well-tested terrestrial biosphere model T&C. The module explicitly distinguishes functional soil organic carbon components. Extracellular enzymes and microbial pools are differentiated based on the functional roles of bacteria, saprotrophic, and mycorrhizal fungi. Soil macrofauna is also represented. The model resolves the cycles of nitrogen, phosphorus, and potassium. Model simulations for 20 sites compared favorably with global patterns of litter and soil stoichiometry, microbial and macrofaunal biomass relations with soil organic carbon, soil respiration, and nutrient mineralization rates. Long-term responses to bare fallow and nitrogen addition experiments were also in agreement with observations. Some discrepancies between predictions and observations are appreciable in the response to litter manipulation. Upon successful model reproduction of observed general trends, we assessed patterns associated with the carbon cycle that were challenging to address empirically. Despite large site-to-site variability, fine root, fungal, bacteria, and macrofaunal respiration account for 33%, 40%, 24%, and 3% on average of total belowground respiration, respectively. Simulated root exudation and carbon export to mycorrhizal fungi represent on average about 13% of plant net primary productivity. These results offer mechanistic and general estimates of microbial biomass and its contribution to respiration fluxes and to soil organic matter dynamics. ©2019. 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/160130
Appears in Collections: 气候变化与战略
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作者单位: Institute of Environmental Engineering, ETH Zurich, Zurich, Switzerland; Department of Physical Geography, Stockholm University, Stockholm, Sweden; Bolin Centre for Climate Research, Stockholm, Sweden; Department of Environmental Science, Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich, Zurich, Switzerland; Department of Civil and Environmental Engineering, Imperial College London, London, United Kingdom
Recommended Citation:
Fatichi S.,Manzoni S.,Or D.,et al. A Mechanistic Model of Microbially Mediated Soil Biogeochemical Processes: A Reality Check[J]. Global Biogeochemical Cycles,2019-01-01,33(6)