Soil Carbon Dynamics and Microbial Interactions

Soil carbon dynamics underpin terrestrial ecosystems and regulate atmospheric chemistry by controlling the storage and release of carbon. Organic carbon in soil exists in diverse forms, from particulate detritus to mineral-bound complexes, and its fate is determined by interactions between soil minerals, organic matter and microbial communities. Microorganisms drive decomposition, nutrient cycling and the transformation of organic inputs into stable pools, while soil properties such as texture, mineralogy and moisture modulate these processes. Microbial functional diversity, including specialist and generalist groups, shapes the pathways of carbon flow and stabilisation. Environmental drivers, notably temperature and moisture, influence microbial activity and the turnover rates of distinct carbon pools, thereby affecting the vulnerability of soils to climate change. Advances in global mapping, model-data integration and mechanistic understanding have begun to reveal the spatial heterogeneity of carbon turnover and the emergent sensitivities of soil carbon to warming. Insight into the microbe-mineral interface is critical for refining Earth system models and for guiding land management strategies to enhance carbon sequestration and mitigate climate feedbacks.

Research from Nature Portfolio

Recent studies have produced a global atlas of mineral-associated and particulate soil carbon, revealing that mineral-bound carbon dominates global stocks with turnover times an order of magnitude longer than particulate pools. This atlas integrates field observations with data-model fusion to map stocks and estimate decomposition rates, highlighting greater warming-induced acceleration of carbon loss in subsoil relative to topsoil. Complementary work has quantified the temperature sensitivity of these pools, showing that particulate carbon decomposition responds more strongly to warming than mineral-protected carbon, particularly in cool climates. Discrepancies among Earth system models in representing the proportion of mineral-protected pools lead to divergent projections of soil carbon age and climate feedbacks. Together, these advances underscore the need to account for distinct soil carbon pools and their interactions with temperature in predictive models.

Soil Carbon Dynamics and Microbial Interactions publication trend

The graph below shows the total number of articles in soil carbon dynamics and microbial interactions across all publications each year (not limited to Nature Index journals).

Technical terms

Soil organic carbon (SOC): The carbon component of soil organic matter derived from plant and microbial residues.

Mineral-associated organic carbon (MAOC): Organic compounds bound to soil minerals, often protected from rapid decomposition.

Particulate organic carbon (POC): Discrete fragments of organic matter, such as plant debris, with relatively fast turnover.

Carbon use efficiency (CUE): The ratio of microbial biomass production to total organic carbon uptake during decomposition.

Earth system model (ESM): A numerical representation of Earth's climate, biogeochemical and physical processes used to simulate carbon-climate interactions.

References

1. Global turnover of soil mineral-associated and particulate organic carbon. Nature Communications (2024).
2. Emergent temperature sensitivity of soil organic carbon driven by mineral associations. Nature Geoscience (2024).
3. Carbon sequestration in the subsoil and the time required to stabilize carbon for climate change mitigation. Global Change Biology (2024).
4. Causes of variation in soil carbon simulations from CMIP5 Earth system models and comparison with observations. Biogeosciences (2013).
5. Integrating microbial physiology and physio-chemical principles in soils with the MIcrobial-MIneral Carbon Stabilization (MIMICS) model. Biogeosciences (2014).