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Isolation and Analysis of Microbial Communities in Soil, Rhizosphere, and Roots in Perennial Grass Experiments
Published on: July 24, 2018
Community composition and functioning of denitrifying bacteria from adjacent meadow and forest soils
J J Rich1, R S Heichen, P J Bottomley
1Departments of Crop and Soil Science, Oregon State University, Corvallis, Oregon 97331, USA.
Applied and Environmental Microbiology
|October 9, 2003
Summary
Denitrifying bacteria communities differ significantly between meadow and forest soils, with meadow soils showing higher activity. Community composition is linked to vegetation and soil properties, primarily featuring Rhizobiaceae in alpha-Proteobacteria.
Area of Science:
- Microbial Ecology
- Soil Science
- Environmental Microbiology
Background:
- Denitrification is a crucial microbial process in nitrogen cycling.
- Understanding denitrifier communities is key to predicting ecosystem functions.
- Spatial variations in soil properties influence microbial community structure.
Purpose of the Study:
- To investigate spatial gradients in denitrifier communities from meadow to forest soils.
- To correlate denitrifier community composition with ecological properties like vegetation and process rates.
- To determine the phylogenetic relationships of denitrifiers using the nosZ gene.
Main Methods:
- Soil samples collected along meadow-forest transects.
- Analysis of denitrifying enzyme activity (DEA) and nitrification potential.
- Molecular analysis using nosZ gene marker and terminal restriction fragment length polymorphism (T-RFLP).
Main Results:
- Significant functional and structural differences in denitrifier communities between meadow and forest soils.
- Meadow soils exhibited an order of magnitude higher DEA compared to forest soils.
- Denitrifier community composition correlated with process rates and vegetation type, with distinct groupings by habitat.
Conclusions:
- Meadow and forest soils harbor distinct denitrifier communities.
- Vegetation type and soil environmental factors influence denitrifier community structure and function.
- Rhizobiaceae (alpha-Proteobacteria) are dominant in these soil denitrifier communities, impacting denitrification variability.
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