Linking resource competition and biodiversity in meta-ecosystems

资源竞争是生态学中最基本的物种相互作用之一。在过去的十年中，它作为生物群落结构和物种丰富度的主要驱动因素得到了广泛的研究。最近，人们越来越认识到，空间结构的群落不仅通过生物的分散联系起来，而且还通过物质和资源的流动联系起来。然而，尽管这样的元生态系统在群落生态学中是一个新兴的话题，但对于物种可能改变资源分布的空间结构环境中的竞争知之甚少。在拟议的研究项目中，我们的目标是获得对元生态系统中资源竞争，生物多样性和生态系统功能之间关系的机制理解。为了解决这个问题，我们将开发一个框架来描述元生态系统中的资源竞争。我们将把元生态系统建模为一个由不同资源水平和比例的分散连接的小块组成的系统。这种方法使我们能够研究空间资源分布对生态系统功能的影响。特别是，我们将(i)确定在空间结构环境中增强竞争能力的物种特征，（ii）量化单一物种如何塑造其空间资源环境，（iii）调查元生态系统中的两物种和多物种竞争，以及最大化生物多样性的条件，（iv）分析资源和生物量分布之间的反馈及其对资源利用、生产力和生物多样性的影响。(5)探讨斑块型元生态系统资源利用、初级生产与生物多样性格局之间的关系。最后，我们有一个独特的机会来验证我们的理论预测，反对实验浮游生物群落在一个类似于化学调节器的系统中，这个系统由连续连接的血管组成，其中两种必需的营养物质从系统的两端供应（所谓的渐变调节器）。我们的方法将能够在系统和斑块水平上评估多样性和生产力，并允许理论研究，产生一种新的、高分辨率的元生态系统过程分析。该项目的研究结果将有助于弥合经典竞争理论与空间结构元生态系统之间的差距，并将对增强我们对野外群落中物种共存和生物多样性功能关系的理解具有普遍意义。

Resource competition is one of the most fundamental species interactions in ecology. It has been studied intensely in the last decade as a major driver for the structure and species richness of biological communities. Recently, it is increasingly acknowledged that spatially structured communities are not only connected by dispersal of organisms but also by flows of matter and resources. However, despite the fact that such meta-ecosystems are an emerging topic in community ecology, not much is known about competition in spatially structured environments where species may modify resource distributions. In the proposed research project we aim to gain a mechanistic understanding about the relationship between resource competition, biodiversity and ecosystem functioning in meta-ecosystems. To address this question we will develop a framework for describing resource competition in meta-ecosystems. We will model a meta-ecosystem as a system of diffusively connected patches that differ in the levels and ratios of resources. This approach enables us to study the effects of spatial resource distributions on the eco-system functioning. In particular, we will (i) determine species traits that enhance competitive abilities in a spatially structured environment, (ii) quantify how a single species shapes its spatial resource environment, (iii) investigate two-species and multi-species competition in a meta-ecosystem, as well as conditions that maximize biodiversity, (iv) analyse feedbacks between resource and biomass distributions, and their influence on the resource-use, productivity and biodiversity, and (v) explore the relationship between resource-use, primary production and biodiversity patterns in patchy meta-ecosystems. Finally, we have the unique opportunity to validate our theoretical predictions against experiments with plankton communities in a chemostat-like system consisting of serially connected vessels where two essential nutrients are supplied from opposing ends of the system (so-called gradostat). Our approach will enable to assess the diversity and productivity both at the system and the patch level and admits theoretical investigations, yielding a novel, high-resolution analysis of meta-ecosystem processes. The results of this research project will help to bridge the gap between classic competition theory and spatially structured meta-ecosystems and will be of general relevance for enhancing our understanding of species coexistence and biodiversity-functioning relationships in field communities.