Plant - soil fauna interactions: soil feedback mechanisms in grassland of different diversity

最近在温带草原进行的长期研究表明，经过一段明显的时间滞后后，地上植物多样性的丧失会导致地下物种灭绝，并导致地下基本功能的显著恶化。这些发现表明，负的多样性损失-功能关系在很大程度上是由土壤反馈机制驱动的。本提案的主要任务是通过侧重于塑造多样性-功能关系的土壤反馈机制，理清耶拿实验头八年观察到的植物多样性效应的潜在机制。作为所有主要实验的基本组成部分，拟议的项目有五个主要目标：(1)调查植物性状多样性的影响，以及性状和植物特有的对土壤微生物和土壤动物的影响。(2)探讨地下资源在多样性-功能关系中的作用。(3)跟踪植物种类和功能群多样性对土壤微生物和土壤动物长期变化的影响。(4)调查不同多样性植物群落受植物入侵后土壤微生物和土壤动物的变化。(5)研究土壤动物在植物多样性梯度中对植物演替和地上多营养相互作用的作用。总体而言，该项目将地下生物群整合为不同多样性植物群落的响应变量和驱动力，旨在更全面和更机械地了解地上-地下的相互关系。

Recent long-term studies in temperate grassland suggest that aboveground plant diversity loss leads to belowground extinction cascades and pronounced deterioration of fundamental belowground functions after a distinct time-lag. These findings suggest that the negative diversity loss – function relationship is driven to a large extent by soil feedback mechanisms. The main task of the present proposal is to disentangle the mechanisms underlying the plant diversity effects observed in the first eight years of the Jena Experiment by focusing on soil feedback mechanisms shaping the diversity – functioning relationship. Being involved and constituting fundamental parts in all major experiments the proposed project has five major goals: (1) Investigate effects of plant trait diversity as well as trait- and plant-specific impacts on soil microorganisms and soil fauna. (2) Investigate the role of belowground resources for the diversity – function relationship. (3) Follow the effects of plant species and functional group diversity on long-term changes in soil microorganisms and soil fauna. (4) Investigate changes in soil microorganisms and soil fauna of plant communities of different diversity invaded by plants. (5) Investigate the role of soil fauna for plant succession and aboveground multitrophic interactions in a plant diversity gradient. Overall, the project integrates belowground biota as response variables and driving forces of plant communities of different diversity and aims at a more comprehensive and mechanistic understanding of aboveground – belowground interrelationships.