Ecosytem functionning at the crossroad of biogeography and community ecology

生态学家一直对生物多样性的空间分布很感兴趣。温度直接影响大地理梯度上的许多生态系统过程，因为它影响生物速率。气候也是许多物种分布和生态相互作用的重要驱动力。然而，在这些事实之间的十字路口发现了一个基本的，仍然没有答案的问题：生物多样性的分布，以及社区生态的发生，在多大程度上影响生态系统功能的全球分布？我的研究计划的长期目标是发展理论，以了解和预测生物多样性分布和生态系统功能在地理空间尺度。更具体地说，我将调查的假设，生态相互作用的架构的空间变化是制约生态系统生产力在地理尺度上，协同作用的直接影响的温度对生物速率。我的具体目标是：i）发展一个数学形式主义，以代表结构的生态系统相互作用网络; ii）综合生态系统的复杂性，分析其维数; iii）形式化和测试定量理论的温度依赖性的营养调节。 我将整合不同的方法来实现我的目标，从数学建模到实验和实地观察。在项目1中，我将重建整个北极的直接和间接生态相互作用网络。我将在分布在梯度上的地点进行实地采样，以记录植物-食草动物，植物-传粉者和捕食者-猎物的相互作用，我将通过动物的迁移和觅食来整合空间交换的知识。在项目2中，我将研究元生态系统的维度。我将量化描述整个北方欧洲的柳树，画廊，寄生虫网络的结构的变化所需的潜变量的数量。在项目3中，我将开发和测试营养调节的温度依赖性的定量理论。我将使用紫色猪笼草叶子上的微生物食物网来参数化模型，并进行实验来测试其定量预测。该项目的优势在于将地理学、群落生态学和生态系统生态学相结合。我将发展的形式主义将使该领域超越“网络的网络”的简单观点。元生态系统是最复杂的生态结构之一，因为它们整合了空间，时间和相互作用，我将量化它们的维度，以挑战社区生态是一团乱麻的观点。最后，我开发的理论将是至关重要的，以了解气候变化和生物多样性丧失对生态系统功能的联合影响。

Ecologists have always been fascinated by the spatial distribution of biodiversity. Temperature impacts directly many ecosystem processes over large biogeographical gradients because it affects biological rates. Climate is also an essential driver of many species ranges and ecological interactions. At the crossroad between these facts is however found a fundamental, and still unanswered, question: to what extent the distribution of biodiversity, and the community ecology taking place, is influencing the global distribution of ecosystem functioning? The long-term objective of my research program is to develop theory to understand and predict biodiversity distribution and ecosystem functioning at biogeographical spatial scales. More specifically, I will investigate the hypothesis that the spatial variation of the architecture of ecological interactions is constraining ecosystem productivity at the biogeographical scale, in synergy with the direct effect of temperature on biological rates. My specific objectives are: i) develop a mathematical formalism to represent the architecture of metaecosystem interaction networks; ii) synthesize the complexity of metaecosystems with analysis of their dimensionality; iii) formalize and test quantitative theory of temperature-dependence of trophic regulation. I will integrate different methodological approaches to reach my objectives, from mathematical modeling to experiments and field observations. In project 1, I will reconstruct the network of direct and indirect ecological interactions across the Arctic. I will conduct field sampling at sites spread across the gradient to document plant-herbivore, plant-pollinator and predator-prey interactions, which I will integrate with knowledge of spatial exchanges by migration and foraging of animals. In project 2, I will investigate the dimensionality of metaecosystems. I will quantify the number of latent variables required to describe the variation in the structure of willows-gallers-parasitoids networks across northern Europe. In project 3, I will develop and test a quantitative theory of temperature-dependence of trophic regulation. I will use the microbial food web inhabiting the leaves of the purple pitcher plants to parameterize the model and conduct experiments testing its quantitative predictions. The strength of this program is based upon the integration of biogeography, community ecology and ecosystem ecology. The formalism I will develop will bring the field beyond the simplistic view of 'networks of networks'. Metaecosystems are among the most complex ecological structures because they integrate space, time and interactions and I will quantify their dimensions to challenge the view that community ecology is a mess. Finally, the theory I develop will be critical to understand the joint effects of climate change and biodiversity loss on ecosystem functioning.