Project Details
Projekt
Microbial growth and respiration kinetics – bridging microbial activity and bioenergetics in soil
Subject Area
Soil Sciences
Microbial Ecology and Applied Microbiology
Microbial Ecology and Applied Microbiology
Term
since 2025
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 554807460
The development of process-based models describing microbial growth and its limitations in soil from a bioenergetic perspective during the first phase of the “SoilSystems“ Priority Program has highlighted critical knowledge gaps and research needs in the field. First among those is the precise estimation of the total and active microbial biomass in the soil, which is essential to develop a mechanistic understanding of the coupled carbon and energy balances and the efficiency of microbial growth. A better estimation of microbial biomass can be achieved by a combination of measurements of the kinetics of substrate-induced microbial respiration, heat release, changes in soil DNA and RNA content and the assessment of microbial life strategies. With the help of this additional information, we want to expand and refine the bioenergetic models developed in the first phase. The resulting model should a) be sufficiently simple to derive the model parameters from respiration kinetics data and from independent measurements of total microbial biomass, b) be able to describe microbial growth from dormancy to unlimited exponential growth in terms of macromolecular cell composition (especially the relative proportion of RNA as a growth-related cell component). Alternative concepts for the description of microbial life strategies, e.g. the r-K-L or the Y-A-S continuum, will be compared using RNA-based molecular methods (metatranscriptomics) on the basis of changes in the expressed functional genes in the microbial community during the substrate-induced growth phase. This will result in an extended, clearly process-based modelling approach, which will subsequently be applied to more complex experimental data sets obtained within the consortium of the Priority Programme. The comparison of different modelling approaches within the consortium will contribute significantly to the synthesis and an improved process understanding of microbial growth in soil.
DFG Programme
Priority Programmes
Subproject of
SPP 2322:
Systems ecology of soils – Energy Discharge Modulated by Microbiome and Boundary Conditions (SoilSystems)
Co-Investigator
Dr. Kenneth Dumack
