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Updated: Jun 24, 2026
10:31
Isolation and Analysis of Microbial Communities in Soil, Rhizosphere, and Roots in Perennial Grass Experiments
Published on: July 24, 2018
Testing the functional significance of microbial community composition
Michael S Strickland1, Christian Lauber, Noah Fierer
1Odum School of Ecology, University of Georgia, Athens, Georgia 30602, USA. strickm@uga.edu
Ecology
|March 28, 2009
Summary
Soil microbial communities significantly impact litter decomposition rates, challenging the assumption of functional redundancy in ecosystem models. Microbial community history with specific litter types influences decomposition, affecting carbon mineralization.
Area of Science:
- Ecology
- Soil Science
- Microbiology
Background:
- Terrestrial ecosystem models often assume soil microbial communities function identically regardless of composition.
- High microbial diversity and adaptability suggest functional redundancy, making this assumption plausible but untested.
Purpose of the Study:
- To test the assumption of functional redundancy in soil microbial communities.
- To determine if microbial community composition influences litter decomposition rates.
Main Methods:
- Experimental microcosms were inoculated with distinct soil microbial communities.
- Litter decomposition rates were measured by quantifying carbon dioxide production.
- Differences in microbial inoculum were analyzed for their effect on carbon mineralization.
Main Results:
- Carbon dioxide production rates from litter decomposition varied significantly based on the microbial inoculum.
- Microbial community composition alone explained approximately 20% of the variation in total carbon mineralized.
- Communities with a shared history with specific foliar litter showed higher decomposition rates.
Conclusions:
- The assumption of functional equivalence among soil microbial communities in the same environment is incorrect.
- Accurate prediction of biogeochemical processes under global change requires considering microbial community composition and adaptation history.
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