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Isolation and Analysis of Microbial Communities in Soil, Rhizosphere, and Roots in Perennial Grass Experiments
Published on: July 24, 2018
Changes in bacterial and archaeal community structure and functional diversity along a geochemically variable soil
Colleen M Hansel1, Scott Fendorf, Phillip M Jardine
1Department of Geological and Environmental Sciences, Stanford University, Stanford, California 94305-2115, USA. hansel@seas.harvard.edu
Applied and Environmental Microbiology
|January 15, 2008
Summary
Soil microbial communities and their functions vary significantly with depth and soil aggregates. These changes are driven by factors like water, pH, and nutrient availability, impacting geochemical cycling.
Area of Science:
- Soil science
- Microbiology
- Geochemistry
Background:
- Soil properties like nutrients, water, pH, and texture create spatial heterogeneity.
- This heterogeneity influences the structure and diversity of soil microbial communities.
- Soil depth and aggregation are key factors in this spatial variation.
Purpose of the Study:
- To investigate microbial and functional community changes within soil aggregates across a soil profile.
- To characterize microbial diversity and functional groups involved in nitrogen, iron, and sulfur cycling.
- To understand the impact of soil depth and aggregation on microbial community structure and metabolic potential.
Main Methods:
- Cultivation-independent analysis of 16S rRNA and functional genes (amoA, dsrAB).
- Cultivation-based analysis of Fe(III)-reducing organisms.
- Coupled molecular and cultivation approaches to analyze microbial communities within soil aggregates.
Main Results:
- Microbial communities, including ammonia-oxidizing and Fe(III)-reducing groups, varied significantly along the soil profile.
- Differences in carbon availability, water content, and pH likely drove these variations.
- Crenarchaeota and ammonia-oxidizing archaeal communities showed similar distribution patterns unique to each soil horizon.
- Soil aggregates harbor microenvironments supporting both anaerobic and aerobic metabolisms.
Conclusions:
- Soil depth and aggregation profoundly impact microbial community structure and function.
- Spatial heterogeneity within soils is a critical factor shaping microbial life and biogeochemical processes.
- Understanding these variations is key to comprehending soil ecosystem dynamics and nutrient cycling.
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