Soil organic matter (SOM) is fundamental to biogeochemical cycles and the ecosystem functions provided by soils. Dynamic interactions between organic matter and soil mineral phases are ultimately linked to the persistence and turnover of SOM across scales ranging from microscopic to global. Soil biogeochemical diversity—encompassing physical, chemical, and biological variations—strongly influences root growth, redox conditions, microbial activity, and element fluxes. These interactions affect SOM and nutrient dynamics, greenhouse gas emissions, groundwater quality, and broader ecosystem processes.
This session is dedicated to studies exploring the dynamic interactions, underlying mechanisms, and implications of organo-mineral interactions at multiple scales, as well as their spatial and temporal heterogeneity within the soil system. It includes research on SOM formation pathways (e.g., plant-, rhizosphere-, microbial-, and pyrogenic-derived), its storage in aggregates, and its association with mineral surfaces, as well as their responses to management practices and global change drivers. Furthermore, studies on nutrient and contaminant behavior, greenhouse gas fluxes, carbon storage, mineral transformations, and related processes—using laboratory, field, modeling, or innovative methodological approaches that enhance our understanding of soils and sediments in biogeochemical cycles—are part of this session. We aim to improve our mechanistic understanding of SOM dynamics and discuss new insights and approaches.
Floriane Jamoteau