DISSERTATION RESEARCH: Food Webs in Space: The Interplay Between Dispersal and Trophic Interactions

营养相互作用（捕食者对猎物的消耗）定义了食物网中能量和营养物质的流动。 许多参与营养相互作用的生物也能够在合适的栖息地之间移动（分散）。 例如，在一个栖息地吃了一个猎物后，捕食者可能会分散到另一个栖息地，然后再吃更多的猎物。 生物的这种扩散可能会影响营养相互作用的结果，通过改变斑块内的种群规模。 与此同时，营养相互作用可能会影响种群规模，从而决定了可分散在斑块中的生物体数量。 因此，营养相互作用和扩散可能联合收割机决定的结构和动态的食物网在当地（内斑块）和区域（斑块）尺度。本研究使用了系统的淡水岩石池阿普尔多岛，缅因州，以确定如何扩散和营养相互作用联合收割机影响当地和区域的食物网动态。 简单的岩石池食物网由浮游植物、食草性浮游动物和捕食性水蝽（Trichocorixa）组成。 先前的研究表明，Trichocorixa的捕食强烈影响当地的食物网，并且Trichocorixa能够在岩石池中分散。 一个现场实验将被用来量化的地方和区域的影响，分散Trichocorixa的岩石池食物网。 一个特定的数学模型已经开发出预测本实验的结果，这个模型将被扩展到其他生态系统，以确定一般的影响，分散对本地和区域food-web dynamics.This研究结合理论和实证方法，以增加理解的作用，空间结构的食物网dynamics. This研究。 因此，这项研究的结果将为受生境破碎化威胁的生态系统的保护和管理提供信息。 该项目支持一名研究生的论文研究，并为本科生提供参与实地研究的机会，作为多所大学实习计划的一部分。 研究结果将通过科学出版物和演讲、本科课程讲座以及与当地高中学生、教师和公众的外联活动广泛传播。

Trophic interactions (the consumption of prey by predators) define the flow of energy and nutrients in food webs. Many organisms involved in trophic interactions are also able to move (disperse) among areas of suitable habitat. For example, after eating a prey item in one patch of habitat, a predator may disperse to another habitat patch before consuming additional prey. Such dispersal of organisms may affect the outcome of trophic interactions by altering the size of populations within patches. At the same time, trophic interactions may influence population sizes, and thus determine the number of organisms available to disperse among patches. As a result, trophic interactions and dispersal likely combine to dictate the structure and dynamics of food webs at the local (within-patch) and regional (among-patch) scales. This study uses a system of freshwater rock pools on Appledore Island, Maine to determine how dispersal and trophic interactions combine to influence local and regional food-web dynamics. The simple rock-pool food web consists of phytoplankton, herbivorous zooplankton, and a predatory water bug (Trichocorixa). Previous research shows that predation by Trichocorixa strongly affects local food webs and that Trichocorixa is capable of dispersing among rock pools. A field experiment will be used to quantify the local and regional effects of dispersal by Trichocorixa on the rock-pool food web. A specific mathematical model has been developed to predict the outcomes of this experiment, and this model will be extended to other ecosystems in order to determine the general effects of dispersal on local and regional food-web dynamics.This study combines theoretical and empirical approaches to increase understanding of the role of spatial structure in food-web dynamics. As such, results of this research will inform the conservation and management of ecosystems threatened by habitat fragmentation. This project supports the dissertation research of one graduate student and provides the opportunity for an undergraduate to be involved in field research as part of a multi-university internship program. Results will be disseminated broadly through scientific publications and presentations, lectures to undergraduate courses, and outreach to local high school students, teachers, and the general public.