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 ; Ecology and Biodiversity of Animals and Ecosystems, Organismic Interactions
• Term: from 2008 to 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 61109404

The proposed project focuses on changes in soil food web structure with forest type / management across the three Biodiversity Exploratories. In close cooperation with the accompanying soil animal projects of Brose, Eisenhauer, Maraun and Ruess the project refines and extends results of the previous phase of the Exploratories on the structure of soil animal food webs. Five work packages (WPs) will be investigated. Using quantitative sampling methodologies density and biomass of soil invertebrates of soil animal communities will be studied in 25 of the Experimental Plots of the forest sites of each of the three Exploratories (WP 1). The study sites include the 16 sites investigated in the previous phases of the Exploratoroies allowing to investigate temporal variations in soil food web structure with forest type / management. WP 2 complements our previous work on soil animal food webs by investigating the structure of enchytraeid and dipteran communities, major soil animal groups neglected so far, as affected by forest type / management. WP 3 focuses on unravelling the trophic structure and trophic links in the fungal energy channel by analysing fungal feeders and their fungal prey using fatty acid and molecular gut content analysis. WP 4 continues investigating the relative importance of belowground resources for soil animal communities in the framework of the "trenchning experiment" established in the last phase of the project. WP 5 investigates the role of bottom-up factors for the assembly of soil animal communities in the framework of a newly established "assembly experiment" of the soil animal ecology groups of the Exploratories. Results of the study will (1) allow to understand the structure and dynamics of forest soil animal food webs in unprecedented detail, and form the basis for modelling these food webs (WPs 1-5); (2) integrate neglected but important soil animal groups in soil food web models (WP 2); (3) open one of the most important soil food web compartments, i.e. that of fungal feeders and their fungal prey (WP3); (4) uncover the role of root derived resources for forest soil food web structure and functioning and its variation with forest type (WP 4); (5) and investigate the relative importance of niche vs. neutral processes for forest soil animal community assembly. 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