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Updated: May 26, 2026
10:31
Isolation and Analysis of Microbial Communities in Soil, Rhizosphere, and Roots in Perennial Grass Experiments
Published on: July 24, 2018
Microbial diversity affects self-organization of the soil-microbe system with consequences for function.
John W Crawford1, Lewis Deacon, Dmitri Grinev
1Faculty of Agriculture, Food and Natural Resources, University of Sydney, Sydney, New South Wales 2006, Australia. john.crawford@sydney.edu.au
Journal of the Royal Society, Interface
|December 14, 2011
Summary
Soil structure self-organizes spontaneously through microbial activity and particle interactions. This process enhances soil hydraulic conductivity and influences its response to environmental changes.
Area of Science:
- Soil Science
- Ecology
- Biogeochemistry
Background:
- Soil pore-scale physical structure is crucial for terrestrial life, regulating air-water balance, nutrient cycling, and carbon sequestration.
- The organizing mechanism behind non-random soil structure remains largely unknown.
- Understanding soil structure is key to predicting ecosystem functions and responses to environmental changes.
Purpose of the Study:
- To investigate the spontaneous self-organization of soil pore-scale structure.
- To elucidate the mechanisms driving soil structure organization, focusing on microbial activity, particle aggregation, and resource flows.
- To assess the impact of self-organization on soil functioning, particularly hydraulic conductivity.
Main Methods:
- Utilized X-ray microtomography and controlled microcosms to observe soil structure formation.
- Employed a simple computational model to simulate self-organization processes involving physical particles and microbes.
- Applied lattice Boltzmann simulations to analyze fluid flow through observed soil structures.
- Manipulated microbial community diversity to link micro-porosity changes with fungal-to-bacterial biomass ratios.
Main Results:
- Provided evidence that soil pore-scale structure organization arises spontaneously from interactions between microbial activity, particle aggregation, and resource flows.
- Computational modeling demonstrated self-organization leading to unique soil material properties.
- Lattice Boltzmann simulations predicted significant increases in hydraulic conductivity due to micro-structural changes.
- Observed a correlation between micro-porosity changes and the ratio of fungal to bacterial biomass.
Conclusions:
- Soil self-organization is a key mechanism shaping pore-scale structure and influencing soil functions.
- This self-organization capacity, linked to microbial community composition, plays a role in soil responses to management and climate change.
- The capacity for soil self-organization has inherent limitations that warrant further investigation.
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