Effects of spatial subsidies and meta-community dynamics on the relationship between island size and food chain length

食物网特性的空间动态和决定因素是理解生物多样性和生态系统功能的核心。传统上，生态系统大小是一个连续的空间变量，用来解释食物链长度的变化。关于陆地系统食物链长度的空间相关性的知识很少，但水生研究表明，生态系统的规模可能具有强大的影响，但并不总是关键的影响。自然生境的开放性导致物质和有机体几乎隐含地跨越生态系统边界和生境斑块之间的流动。这些空间补贴和元群落动态代表着不连续的空间变量，这些变量往往对当地的食物网产生最持久的影响。然而，它们对许多食物网络特性的影响尚不清楚，例如食物链的长度。通过结合经典的数值群落响应和稳定同位素技术，我们的建议将连续空间(岛屿区域)与空间补贴和元群落动力学这两个最显著的不连续空间过程相结合，以探讨它们对节肢动物食物链长度、动态和结构的影响。在将湖岛作为研究地点时，我们的研究计划基于经典的岛屿生物地理学，这是现代生态学中关于空间过程的最基本和最受认可的理论。现代技术、理想的自然实验条件和合理的理论方法的协同作用将极大地促进我们对陆地系统中群落和食物网格局的影响因素的理解。

The spatial dynamics and determinants of food web properties are central to the understanding of biodiversity and ecosystem function. Traditionally ecosystem size, a continuous spatial variable was used to explain variations in food chain length. Knowledge on the spatial dependencies of food chain length in terrestrial systems is scarce, but aquatic studies show that ecosystem size may be of strong, but not always pivotal influence. The openness of natural habitats leads to an almost implicit flux of materials and organisms across ecosystem boundaries and between habitat patches. These spatial subsidies and meta-community dynamics represent discontinuous spatial variables, which often have the most perpetual influences on local food webs. However, their influence on many food web properties, such as food chain length is unexplored. By combining classical numerical community responses and stable isotope techniques, our proposal integrates continuous space (island area) with spatial subsidy and meta-community dynamics, both being the most prominent discontinuous spatial processes, to explore their influence on food chain length, dynamics and structure of arthropod food webs. In using lake islands as study site, we base our research program on classical island biogeography, the most basic and approved theory on spatial processes in modern ecology. The synergy of modern techniques, ideal natural experimental conditions and sound theoretical approaches will significantly advance our understanding of the factors governing community and food web patterns in terrestrial systems.