Project Details
Projekt
Locating microbial metabolite hotspots to resolve soil energy and organic carbon dynamics (SoilEnergySpots)
Applicants
Professorin Dr.-Ing. Mirjana Minceva; Dr. Steffen Schweizer; Professorin Nicole Strittmatter, Ph.D.
Subject Area
Soil Sciences
Term
since 2025
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 554827041
In the SoilEnergySpots project, we aim to advance the understanding of the influence of organic carbon accessibility on energy dynamics in soils. Using an agricultural model soil, we apply widespread microbial metabolic model compounds with different energy contents. Our experimental approaches aim to incubate different sized aggregate structures and other treatments that inhibit spatial accessibility and thus energy conversion. By developing and adapting spatial metabolomics methods on soil samples, we determine the fine-scale distribution of different microbial metabolites, which enables identifying necromass hotspots based on the distributions of amino sugars, for example. We combine this with the spatial analysis of 13C-labeled substrate distribution across mineral surfaces using NanoSIMS. In a further experiment, we investigate the role of the distribution of maize litter and how the added energy from the model metabolites could inhibit or enhance the formation of mineral-associated organic matter affecting carbon storage in soils. We complement the experimental work in SoilEnergySpots with a thermodynamic modeling approach that incorporates the spatial accessibility of different pools of organic matter into the dynamic equilibrium of mass fluxes and enthalpy. Through calorimetric quantification during conversion and determination of the fine-scale distribution of model metabolites, we aim to uncover underlying biogeochemical factors that lead to spatially segregated energetic spots with locally different microbial efficiencies in the soil structure. We hypothesize that the spatially heterogeneous arrangement of soil spots with different energetic efficiencies is an important boundary condition and significantly controls the dynamics of organic carbon and energy in soils. As an interdisciplinary team from soil science, biothermodynamics and analytical chemistry, we aim to complement each other's expertise and approaches and contribute to a broader conceptual understanding of the energetic drivers of organic matter transformation.
DFG Programme
Priority Programmes
