Soil Organic Carbon Dynamics and Management in Agricultural Ecosystems

Soil organic carbon (SOC) is a central determinant of soil fertility, structure and resilience in agricultural systems, underpinning nutrient cycling, water retention and greenhouse-gas fluxes. Dynamics of SOC reflect a balance between inputs—plant residues, root exudates and organic amendments—and losses through microbial respiration, erosion and leaching. Partitioning of SOC into particulate organic matter (POM) and mineral-associated organic matter (MAOM) pools governs stability: POM is a source of readily decomposable carbon and precursor to MAOM, whereas MAOM can persist for centuries through organo-mineral associations. Agricultural management practices, including crop rotation, reduced tillage, cover cropping and targeted organic or mineral amendments, modulate SOC input rates, aggregation and microbial transformation pathways. Spatial variation in soil texture, climate and land use history further influences the capacity of soils to sequester carbon. Global assessments underscore substantial undersaturation of MAOM in cultivated soils, signalling both unrealised sequestration potential and priority regions for intervention. Effective SOC management thus requires system-specific strategies that integrate residue management, soil physical protection and microbial community modulation to enhance long-term carbon stabilisation while supporting productivity and climate mitigation objectives.

Research from Nature Portfolio

Recent studies have advanced multi-pool frameworks for soil carbon management, emphasising context-dependent strategies that recognise soils as complex systems. One investigation demonstrates that augmenting both POM and MAOM pools, rather than targeting one fraction alone, yields more durable carbon gains across diverse environments by aligning residue inputs with microbial turnover pathways and aggregation processes. Another global assessment of mineral-associated carbon stocks reveals that cultivated soils currently store less than half of their mineralogical capacity, with deeper layers and intensively managed regions most undersaturated. This work quantifies sequestration efficiency—the ratio of realised to potential MAOM storage—and shows that soils furthest from capacity accrue carbon at rates three times higher than those closer to saturation. These insights identify priority zones for carbon-enhancing practices and underscore the role of mineral-organic associations in long-term SOC persistence.

Soil Organic Carbon Dynamics and Management in Agricultural Ecosystems publication trend

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

Technical terms

Soil organic carbon (SOC): The carbon component of soil organic matter, encompassing decomposed plant and microbial residues.

Particulate organic matter (POM): Discrete organic fragments, often plant residues, that are relatively unprotected and decompose rapidly.

Mineral-associated organic matter (MAOM): Organic compounds stabilised through chemical and physical bonds with mineral particles, exhibiting long persistence.

Carbon sequestration: The process of capturing atmospheric carbon dioxide and storing it in soil organic matter pools.

Sequestration efficiency: The ratio of actual carbon accrual in a given soil pool to the theoretical maximum storage capacity set by soil mineralogy and structure.

References

1. Unlocking complex soil systems as carbon sinks: multi-pool management as the key. Nature Communications (2023).
2. Global stocks and capacity of mineral-associated soil organic carbon. Nature Communications (2022).
3. Particulate organic matter as a functional soil component for persistent soil organic carbon. Nature Communications (2021).
4. Soil organic carbon pools under long-term mineral and organic amendments: a multisite study. Carbon Research (2024).
5. Global meta-analysis of the relationship between soil organic matter and crop yields. The Soil (2019).
6. Soil Fungal:Bacterial Ratios Are Linked to Altered Carbon Cycling. Frontiers in Microbiology (2016).