Topic 1 : Quantification of organic carbon and characterisation of soil organic matter at plot and regional scales
Numerous analytical approaches are available to quantify soil carbon and to characterise soil organic matter.
Regardless of the robustness of the analytical approach, sampling strategies should be relevant to allow assessment of the spatial heterogeneity and representativeness of the measurements.
This session will discuss problems with existing soil sampling strategies and explore novel analytical approaches for quantifying and characterizing organic and inorganic carbon.
Contributions will focus on new proxies of soil carbon and organic matter, on soil sampling strategies and spatial assessment in various contexts of soil management and pollution, on remote or proxy sensing, and on concepts that allow to better describe soil organic matter in terms of lability/stability.
Topic 2 : Stabilisation of soil organic matter: a central process in C-storing agricultural practices
Soil organic matter is the largest terrestrial organic carbon pool and plays a major role for physical, chemical, and biological properties of soils.
Soil organic carbon content is controlled by the balance between inputs and losses, and by stabilisation processes involving interactions with the mineral soil matrix.
This session will focus on soil organic matter transformation and stabilisation mechanisms that lead to organic carbon sequestration in soils.
Presentations will emphasize the role of occlusion processes and interactions in presence of mineral particles and metal cations, as well as the kinetics (hot moments) and the spatialisation (hot spots) of these processes implementation.
Topic 3 : The role of biodiversity in soil organic matter stabilisation and carbon storage
Soil organisms, including macrofauna, mesofauna and microorganisms, are involved in many soil processes and contribute to soil health and ecosystem services.
In recent years, significant advances have been made in understanding their role in stabilising soil organic carbon.
This session aims at addressing the links between taxonomic and functional diversity, abundance of soil organisms and soil carbon cycling and sequestration. Contributions on how interactions between soil organisms control soil organic matter stabilisation at different scales and what are the biological mechanisms driving the effects of biodiversity on this process are of great interest. The impact of environmental changes, such as land conversion, pollution or climate change, under given agricultural practices, on soil organisms and the studies on bio-indicators of these changes and practices will also be a focus of this session.
Topic 4 : Microbiological, geochemical and matter transfer interactions: an integrated approach
Soil carbon stabilisation is the result of a combination of interacting biological, abiotic geochemical, and physical processes.
This session will provide a systemic view by addressing the combination of different processes and drivers involved in soil carbon stabilisation. These include, but are not limited to, the burial and/or transformation of organic residues into detritivore faeces, the formation of microbial necromass, complexation with metals and adsorption onto soil minerals that vary with numerous processes affecting soil aeration, pH etc. Carbonate mineral formation could be one of the topics addressed, as well as the fate of dissolved carbon, whether in organic or inorganic form. The modelling of interactions between soil organisms and their impacts on the fate of organic matter, carbon sequestration, and nutrient cycling will also be a focus of this session, as well as the impacts of changes in climate, land use change and agricultural practices.