Priority Programme “Systems ecology of soils – energy discharge modulated by microbiome and boundary conditions (SoilSystems)” (SPP 2322)
Deadline: 1. Juli 2024
The Senate of the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) established the Priority Programme SoilSystems in 2021. The programme is designed to run for six years. The present call invites proposals for the second three-year funding period.
The key concept of this Priority Programme is that soil systems, their biodiversity and ecosystem services are determined by energy and matter fluxes derived from the (trans-)formation of SOM, bio- and necromass, which are subject to thermodynamic principles. SoilSystems links thermodynamic state variables (Gibbs energy, Enthalpy and Entropy) with processes of soil organic carbon turnover in order to gain a systemic view on energy and matter fluxes and their relationships to biota, non-living soil components and prevailing environmental conditions. This will enable improved assessment and prediction of dynamic biogeochemical processes, boundary conditions and performance limits, also by taking advantage of modelling approaches to address the complexity of energy-driven soil systems.
The premise of SoilSystems is that soil ecosystem structure, function and stability are controlled by energy dissipation, and that the flux of matter and energy through SOM is modulated by the microbiome. This leads to the main hypotheses:
A: The microbiome drives and modulates energy dissipation and matter turnover along various biological ‘energy use channels’. Microbial carbon turnover and sequestration, including recycling, are part of the energy-use-channels and contribute dominantly to SOM, e.g. by stabilising necromass. Necromass is the dominant ‘contributor’ to SOM.
B: Energy and matter input, discharge and utilisation in the soil system affect biological complexity, i.e. the structural and functional diversity as well as the organisation of the soil microbiome and higher-level trophic networks.
C: The boundary and system conditions, including the soil matrix, minerals and microhabitat structure shape the energy and matter dynamics of soil biota. The activities of soil biota lead to the emergence of functional behaviour, non-equilibria and dissipative steady states that can be characterised by thermodynamic optimality concepts.
Individual projects or project clusters should address these hypotheses with a clear focus on the application of energy and C mass balances for studying the link between substrate turnover and microbial ecology on the basis of thermodynamic state variables. This should encompass at least one of the topics: energy dissipation and matter fluxes in microbial communities and to higher trophic levels, energy and carbon use efficiency including microbial growth yields, substrate ecological stoichiometry and energy use limitations as well as carbon and energy storage in SOM. Steady state levels and gradients of substrates and energy should be related to system and boundary conditions.
