Microbial Weathering Processes in Soil Ecosystems

Microbial weathering in soils encompasses the biological mechanisms by which microorganisms drive the breakdown, alteration and mobilisation of minerals. Through a suite of chemical, physical and biochemical strategies—ranging from acidification and organic ligand production to redox transformations and mechanical penetration—bacteria, fungi and archaea accelerate silicate and carbonate dissolution, release essential nutrients and contribute to soil formation. These processes underpin nutrient cycling, influence soil structure, regulate carbon sequestration and feed back on plant growth and ecosystem resilience. The interplay between root‐associated microbes and free‐living communities creates a dynamic continuum in which secreted metabolites, biofilms and hyphal networks orchestrate mineral breakdown at micro‐ to mesoscales, while cumulative effects manifest at landscape and global scales. Advances in molecular, isotopic and imaging techniques have revealed how carbon allocation by plants, mycorrhizal symbioses and microbial community composition coalesce to control the rates and pathways of mineral weathering, with far‐reaching implications for sustainable forestry, agriculture and carbon dioxide removal strategies.

Research from Nature Portfolio

Foundational work has delineated how ectomycorrhizal fungi associated with different tree hosts secrete organic acids in a mineral‐specific manner, substantially enhancing calcium and magnesium liberation from silicate and carbonate substrates. This mineral‐targeted chelation alters local pH and facilitates sustained nutrient fluxes to trees. Complementary studies have demonstrated that tree species exert a strong selective pressure on the composition and function of rhizosphere microbiomes, with deciduous and coniferous hosts enriching distinct bacterial and fungal assemblages that differ in their weathering efficacy. Investigations across natural soil toposequences further reveal that variations in parent material and nutrient availability drive functional shifts in the rhizosphere microbiome, yet a core set of genes for nutrient cycling is maintained to support plant nutrition under contrasting soil chemistries.

Microbial Weathering Processes in Soil Ecosystems publication trend

The graph below shows the total number of articles in microbial weathering processes in soil ecosystems across all publications each year (not limited to Nature Index journals).

Technical terms

Ectomycorrhiza: A symbiotic association between fungal hyphae and plant roots that enhances nutrient exchange and mineral weathering.

Rhizosphere: The zone of soil surrounding plant roots characterised by distinct chemical gradients and microbial activity.

Biofilm: A structured microbial community embedded in an extracellular matrix, facilitating surface attachment and collective metabolism.

Organic chelator: Low‐molecular‐weight organic compound secreted by organisms to bind and solubilise metal ions from minerals.

References

1. Oxalate secretion by ectomycorrhizal Paxillus involutus is mineral-specific and controls calcium weathering from minerals. Scientific Reports (2015).
2. Specific impacts of beech and Norway spruce on the structure and diversity of the rhizosphere and soil microbial communities. Scientific Reports (2016).
3. Taxonomic and functional shifts in the beech rhizosphere microbiome across a natural soil toposequence. Scientific Reports (2017).
4. Organic carbon source controlled microbial olivine dissolution in small-scale flow-through bioreactors, for CO2 removal. npj Materials Degradation (2024).
5. Ectomycorrhizal fungi integrate nitrogen mobilisation and mineral weathering in boreal forest soil. New Phytologist (2023).
6. Reviews and syntheses: Biological weathering and its consequences at different spatial levels – from nanoscale to global scale. Biogeosciences (2020).