Research

Forest soils are the focus of our research. We understand soils as the subterranean part of forest ecosystems and place our process-oriented soil chemistry, soil physics and soil biology research in the context of forest ecosystem research.

The members of the Chair of Soil Ecology Freiburg use many different approaches for their research. What unites us is our focus on integrating soil properties that result from these ecosystem interactions. Such integrating soil properties are, for example, the soil structure or the humus form of the soil. In various research projects, we try to link the controlling processes of these soil properties to the functions and functioning of soils, but also to consider them for the development of soil protection concepts or the regeneration of soils.

Research Projects

Ecosense SFB 1537

Tracing soil ecological processes of the CO₂ flux

This subproject investigates the spatial and temporal variability of soil fluxes as well as microclimatic and edaphic conditions. The aim is to better understand the role of rhizosphere and microorganisms and to identify so-called ‘hot spots’ and ‘hot moments’ of microbial activity and root respiration of trees. This will provide us with valuable insights into the complex interactions in the soil and their significance for the ecosystem.

Research Project

Abiotic lignin degradation: key to litter conversion on disturbed areas in the forest?

Disturbances such as drought or storms that lead to the loss of the canopy influence the carbon cycle in forests through abiotic lignin degradation. This process, which is enhanced by light and heat, changes the quality of soil organic matter and favours bacteria over fungi. Our research project investigates these processes and their effects on the decomposition of litter and the long-term stability of organic matter in disturbed forest ecosystems. We want to find out how these abiotic influences change the ecosystem in the long term.

Collaborative Project

Increasing carbon
sequestration in forest soils through targeted deadwood management

Subproject 2:
Carbon stabilization and soil structure

In this collaborative project, the contribution of lying deadwood to the enrichment of soil carbon stocks in forests is being investigated. By sampling the soil solid, liquid and gas phases, all possible input and output pathways of organic carbon are analysed and quantified. In addition, forestry (stand density, crown cover) and site-specific factors (exposure, slope inclination) are analysed in order to determine their influence on the above-mentioned material flows/carbon stores and to derive management recommendations from this.

Collaborative Project

Relevance of the forest soil microbiome for nutrient cycles and influences of tree species and
climate

Subproject 1:
Importance of bacteria and fungi for nutrient cycles in acidic forest soils

The aim of this research project is to investigate the influence of climatic characteristics and tree species on the microbial community and to analyse their role in ensuring soil-associated ecosystem services. The biodiversity and functional potential of the soil microbial community will be determined by sequencing the metagenome and the metatranscriptome.

SoilSystems SPP 2322

Sorption thermodynamics and aggregation as control factors for microbial substrate utilization and mineralization

The stabilisation of organic matter against microbial use and mineralisation in the soil has not yet been quantified. Furthermore, the influence of soil aggregation and soil microbial diversity on this relationship is unknown. Based on studies with 14C-labelled model substrates and model minerals, the Gibbs free energies of the sorption reactions, the sorption enthalpies and entropies, the activation energies of the desorption reactions and the losses of molar free energy due to sorption hysteresis are determined in this subproject.

Research Project

Analysis of soil
biodiversity on compacted forest soils as a function of temporary drought

This project will make an important contribution to the systematic investigation of the microbiome and soil fauna on travelled forest soils. At the same time, this project will focus on the investigation of soil biodiversity and the influence of dry periods and droughts as a result of climate change. This link also allows conclusions to be drawn about the regenerative capacity of travelled forest soils and the effect of soil biodiversity on soil functions.