Multi-trophic energy fluxes in soil food webs along plant diversity–productivity gradients

正如复杂的食物网所描述的那样，植物以多种方式与其他生物相互作用。生物多样性（即植物物种数量）和生态系统功能（即植物生物量）之间关系强度的变化可能是由这些相互作用的改变引起的。随着时间的推移，植物多样性高和低的样地可能分别通过有益和有害的相互作用促进能量通量。在该项目中，我们旨在系统地解决(1)土壤食物网的能量通量如何沿着植物多样性的梯度变化，以及(2)这些关系如何随着土壤历史和植物历史的变化而变化。我们将首先测试植物多样性和土壤历史对田间试验（WP1）群落食物网能量通量强度的影响。这将通过分析在Ecotron （WP2）控制条件下植物历史和土壤历史的差异如何改变这些效应来补充。最后，将对田间试验和Ecotron土壤食物网的结构进行更详细的分类分析，以确定驱动上述能量通量变化的关键种群（WP3）。总之，这些工作包将为受植物多样性、土壤历史和植物历史影响的土壤食物网的能量结构提供独特的见解。地下消费者能量通量的差异将导致显著的反馈效应，这将是通过多营养相互作用机制解释生物多样性-生态系统功能关系的关键。

Plants interact with other organisms in many ways as depicted by complex food webs. Changes in the strength of the relationship between biodiversity (i.e. the number of plant species) and ecosystem functioning (i.e. plant biomass) may be caused by modifications of these interactions. Over time, plots of high and low plant diversity may foster energy fluxes through interactions that are beneficial and detrimental, respectively. In the proposed project, we aim at systematically addressing (1) how the energy fluxes through the soil food webs change along a gradient in plant diversity, and (2) how these relationships change with soil history and plant history. We will start by testing for effects of plant diversity and soil history on the strength of food-web energy fluxes in the communities of the Field Experiment (WP1). This will be complemented by analyses how differences in plant history and soil history change these effects under the controlled conditions of the Ecotron (WP2). Finally, the structure of the soil food webs in the Field Experiment and the Ecotron will be analyzed in more taxonomic detail to allow for the identification of keystone populations that drive the above-mentioned modifications in energy fluxes (WP3). Together, these work packages will provide unique insights into the energetic structure of soil food webs as affected by plant diversity, soil history, and plant history. Differences in energy fluxes to belowground consumers will result in significant feedback effects that will be key to mechanistically explain biodiversity-ecosystem function relationships through multi-trophic interactions.