Changes in soil food web structure of the decomposer system with land-use intensity in forest systems

• Applicant: Professor Dr. Stefan Scheu
• Subject Area: Ecology and Biodiversity of Plants and Ecosystems
• Term: since 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 324888848

The proposed project focuses on changes in soil food web structure with forest gap formation as investigated in the framework of the Forest Gap Experiment (FOX) of the three Biodiversity Exploratories. The project refines and extends results of the previous phases of the Exploratories on the structure of soil animal food webs of forests of different land-use intensity / forest management by focussing on consequences of strong disturbances. Four work packages (WPs) will be investigated. WP1 analyses data over a period of 12 years taken at three year intervals (2008 – 2020) across the three Exploratories on the density, biomass and community structure of soil meso- and macrofauna invertebrates; the study aims at exploring driving factors of the long-term dynamics of soil animal communities and food web structure in forests differing in land-use intensity / forest management. WP2 focuses on investigating changes in soil animal communities and food web structure due to strong disturbances (gap formation, deadwood placement) as investigated in the framework of the FOX experiment. WP3 focuses on analysing energy channelling through soil animal food webs as affected by gap formation and placement of deadwood based on compound–specific amino acid analysis as well as bulk stable isotope analysis. WP4 explores community assembly processes of two main soil mesofauna taxa, Collembola and Oribatida, using community phylogenetics; combining community phylogenetics with trait-based approaches it aims at identifying mechanisms responsible for the assembly of soil animal communities as affected by gap formation and deadwood placement. Results of the study will (1) allow to understand the structure and dynamics of forest soil animal food webs in unprecedented detail, and extend modelling these food webs including changes in time and due to strong disturbances (WP1, WP2), (2) gain insight into the sensitivity of belowground food webs of forests to strong disturbances (WP2, WP3), (3) use novel methodologies to unravel the channelling of energy through soil food webs and its modification by strong disturbances (WP3), and (4) explore assembly processes of decomposer soil invertebrate communities and their modification by strong disturbances (WP4). Overall the project will allow understanding the structure of forest soil food webs, their variations in space and time, and their structuring forces in unprecedented detail, thereby forming an essential component of the variations in the structure and functioning of forest ecosystems with diversity and human impact as investigated in the framework of the Biodiversity Exploratories.

• DFG Programme: Infrastructure Priority Programmes
• Subproject of: SPP 1374: Biodiversity Exploratories