Information for Researchers, No. 1 | April 17, 2024

Priority Programme “Systems ecology of soils – energy discharge modulated by microbiome and boundary conditions (SoilSystems)” (SPP 2322)

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.

All projects must use a systems approach and should build upon the findings of the first phase; see information on the SPP website mentioned under the link below. Projects should work with the soils and substrates of known energy content and stoichiometry as defined in the Common Experimental Platform. According to the systems ecology approach and in line with the suggested energetic framework, complete mass and energy balances including CO2 emissions must be determined in the experiments along with all relevant parameters. Preferably, experiments are conducted in microcosms under control of matter input and output and boundary conditions. They should range from molecular scale to decimetre scale and show the ecological relevance and the relations towards the larger ecosystem. 

Isotope probing approaches for balancing are expected, combined with high-resolution biomarker analyses, calorimetric experiments, Gibbs energy assessments and modelling. State of the art techniques need to be included, for example ‘omics’ techniques to evaluate the diversity, processes and responses of the soil microbiome, or high-resolution MS and 3D imaging for soil microstructure analysis and chemical mapping to visualise solute fluxes and spatial arrangements.

This call particularly invites proposals from interdisciplinary teams representing expertise from soil biogeochemistry, microbiology, ecology, molecular biology, biophysics, bioinformatics, statistics and modelling. Expertise in the field of thermodynamics is required.

Additional information on SPP 2322, including the Common Experimental Platform, suggested techniques and modelling approaches should be taken from the SoilSystems website (see link below). 

Proposals must be written in English and submitted to the DFG by 1 July 2024. Please note that proposals can only be submitted via elan, the DFG´s electronic proposal processing system. To enter a new project within the existing Priority Programme, go to Proposal Submission – New Project/Draft Proposal – Priority Programmes and select “SPP 2322/2 – SoilSystems” from the current list of calls. 

In preparing your proposal, please review the programme guidelines (DFG form 50.05, section B) and follow the proposal preparation instructions (DFG form 54.01). These forms can either be downloaded from the DFG website or accessed through the elan portal. In addition to submitting your proposal through elan, please send an electronic copy to the programme coordinator. 

Applicants must be registered in elan prior to submitting a proposal to the DFG. If you have not yet registered, please note that you must do so by 1 May 2024 to submit a proposal under this call; registration requests received after this time cannot be considered. You will normally receive confirmation of your registration by the next working day. Note that you will be asked to select the appropriate Priority Programme call during both the registration and the proposal process. 

Details of the research concept of the programme, the focal topics and the Common Experimental Platform will be presented at an organisational applicants’ workshop to be held in May 2024. This meeting provides the opportunity for the initiation of joint proposals and is supposed to harmonise and coordinate individual grant proposals of the second phase. Participation is only for researchers eligible to submit proposals to the DFG and upon prior registration at the website (Deadline 1 May 2024). Participants may introduce their research approach briefly (2 minutes) using a template that can be found at the programme’s website. 

Further Information

More information on the Priority Programme is available under: 

The elan system can be accessed at:

DFG forms 50.05 and 54.01 can be downloaded at:

For scientific enquiries concerning the Priority Programme, please contact: 

  • Professor Dr. Sören Thiele-Bruhn
    Universität Trier
    FB VI – Raum- und Umweltwissenschaften
     Fach Bodenkunde
    Campus II
    Behringstraße
    54296 Trier
    phone +49 651 2012241
  • Professor Dr. Matthias Kästner
    Helmholtzzentrum für Umweltforschung – UFZ
    Themenbereich Nachhaltige Technologien für die Umwelt
    Department Umweltbiotechnologie
    Permoserstr. 15
    04318 Leipzig
    phone +49 341 6025-1235
  • Dr. Marcel Lorenz
    Universität Trier
    FB VI – Raum- und Umweltwissenschaften
    Fach Bodenkunde
    Campus II
    Behringstraße
    54296 Trier
    +49 341 6025 2494

Questions on the DFG proposal process can be directed to:

Programme contact: 

Administrative contact: