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

拟议的项目侧重于研究三个生物多样性实验区森林类型/管理对土壤食物网结构的影响。与Brose、Eisenhauer、Maraun和Ruess的土壤动物项目密切合作，该项目完善并扩展了前一阶段关于土壤动物食物网结构的探索成果。将调查五个工作包。采用定量采样的方法，在3个试验区（WP 1）的25个试验区研究土壤动物群落的土壤无脊椎动物密度和生物量。研究地点包括探索项目前几个阶段调查的16个地点，这些地点允许调查土壤食物网结构随森林类型/管理的时间变化。WP 2通过调查受森林类型/管理影响的主要土壤动物类群——蛭形动物和双翅目动物群落的结构，补充了我们之前在土壤动物食物网方面的工作。WP 3侧重于通过脂肪酸和分子肠道含量分析分析真菌食用者及其真菌猎物，揭示真菌能量通道的营养结构和营养环节。在项目最后阶段建立的“挖沟实验”框架内，第四工作组继续调查地下资源对土壤动物群落的相对重要性。WP 5在新建立的土壤动物生态群落“组装实验”框架下，研究了自下而上因素对土壤动物群落组装的作用。研究结果将：(1)使我们能够以前所未有的细节了解森林土壤动物食物网的结构和动态，并为这些食物网的建模奠定基础（WPs 1-5）；(2)在土壤食物网模型中整合被忽视但重要的土壤动物类群（WP 2）；(3)打开最重要的土壤食物网区室之一，即真菌食用者及其真菌猎物区室（WP3）；(4)揭示根系资源在森林土壤食物网结构和功能中的作用及其随森林类型的变化（WP 4）；(5)研究生态位与中性过程对森林土壤动物群落的相对重要性。总体而言，该项目将以前所未有的细节了解森林土壤食物网的结构、时空变化及其结构力，从而形成在生物多样性探索框架内调查的森林生态系统结构和功能变化的重要组成部分，其中包括多样性和人类影响。

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.