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Published on: July 24, 2018
Toward an ecological classification of soil bacteria
Noah Fierer1, Mark A Bradford, Robert B Jackson
1Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado 80309, USA. noahfierer@gmail.com
Ecology
|July 3, 2007
Summary
Soil bacteria communities are linked to carbon availability. Certain bacterial phyla, like Acidobacteria, thrive in low-carbon (oligotrophic) soils, while others, such as Bacteroidetes and beta-Proteobacteria, prefer high-carbon (copiotrophic) environments.
Area of Science:
- Soil Microbiology
- Microbial Ecology
- Environmental Science
Background:
- Soil harbors diverse bacterial communities, but their ecological roles remain poorly understood.
- Understanding bacterial abundance in relation to soil properties is crucial for ecological interpretation.
Purpose of the Study:
- To investigate the relationship between major soil bacterial phyla abundances and soil characteristics.
- To determine if soil bacteria can be categorized into ecologically meaningful groups based on their abundance patterns.
Main Methods:
- Collected 71 diverse North American soil samples.
- Analyzed relationships between soil properties and abundances of six dominant bacterial phyla.
- Conducted a 12-month soil amendment experiment with varying carbon (C) availability.
- Performed meta-analysis on published bacterial clone libraries.
Main Results:
- Net carbon (C) mineralization rate was the best predictor of bacterial phyla abundance.
- Acidobacteria abundance negatively correlated with C mineralization rates.
- Beta-Proteobacteria and Bacteroidetes abundances positively correlated with C mineralization rates.
- Experimental and meta-analytical approaches confirmed these findings.
Conclusions:
- Soil bacterial phyla can be classified as copiotrophic (high C-loving) or oligotrophic (low C-loving).
- This classification aids in predicting bacterial ecological attributes and understanding soil microbial community structure and function.
- The copiotroph-oligotroph concept provides a framework for interpreting soil bacterial ecology.
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