How are soil functions influenced by land use and biodiversity?
As part of the Biodiversity Exploratories, we are investigating how land use and biodiversity influence the interacting carbon and nutrient cycles in the soil.
As the core project soil, we provide important information on soil properties and functions from all 300 experimental plots of the Biodiversity Exploratories for the overall project. We are significantly involved in the coordination and implementation of joint soil sampling of core and sub-projects working in soil biology, microbiology and soil science and in synthesis activities.
Our project includes:
(1) The monitoring of relevant soil properties such as enzyme activities in the Biodiversity Exploratories.
(2) The monitoring of litterfall on the forest plots
(3) The determination of nutrient removal from the soil (N, P, S, K, Mg, Ca) (in situ)
(4) The measurement of autotrophic and heterotrophic soil respiration and its seasonal variability (in situ)
(5) To study the formation and turnover of mineral-associated soil organic matter with mineral bags (in situ)
(6) To investigate the importance of nutrient availability (N,P) for soil organic matter mineralisation and rhizosphere priming (lab incubations).
We are guided by the hypothesis that increased management intensity reduces carbon and nutrient stocks in forest soils, while this effect is less visible in grassland soils due to fertilisation.
We address the following guiding questions:
- How do land use and biodiversity affect the carbon and nutrient balance of soils? What feedback mechanisms occur?
- Are short-term and long-term forest and grassland management reflected in soil properties and especially in soil carbon turnover?
- Which microbial groups respond most strongly to the addition of readily available carbon and nutrient sources?
- What role do land use and biodiversity play in carbon and nutrient mineralisation? How are carbon and nutrient mineralisation coupled? How do the nutrients released by mineralisation behave in the soil?