DISSERTATION RESEARCH: The Impact of Specialist Insect Herbivores on Plant Community Composition.

不同物种在自然植物群落中的相对丰度受植物物种之间竞争的结果和草食动物的影响，但我们缺乏对这些力量如何在自然系统中相互作用的一般理解。 近年来，人们越来越清楚地认识到，物种的空间组织对这些物种如何相互作用有着深远的影响。 陆生植物的不动性使植物竞争成为一个高度局部化的过程。 然而，由移动的食草动物造成的破坏是在区域范围内发生的。 我将使用空间明确的数学模型，结合实地实验，调查这些本地和区域的过程之间的相互作用，在确定其自然栖息地的植物物种的组成和相对丰度。一枝黄花甲虫（Trirhabda属）已知达到极高的种群密度，并杀死其宿主植物，高一枝黄花（Solidago altissima）。 S.高羊茅是一种竞争优势植物，因此这种强烈的食草性大大减少了对其他植物物种的竞争压力，导致它们的丰度发生巨大变化。 我将使用三杆-一枝黄花系统的数据来测试我的空间模型解释自然植物种群丰度模式的能力。这项工作将包括一个独特的空间尺度在塑造物种相互作用的作用检查。 通过将空间生态模型和实地数据结合起来，我的研究将促进可广泛应用于环境科学的数学方法的发展。

The relative abundances of different species in natural plant communities is influenced by the outcome of competition among plant species and by herbivory, yet we lack a general understanding of how these forces interact in natural systems. In recent years, it has become increasingly clear that the spatial organization of species has a profound impact on how those species interact. The immobile nature of terrestrial plants makes plant competition a highly localized process. Damage by mobile herbivores, however, occurs over a regional scale. I will use spatially-explicit mathematical models, in conjunction with field experiments, to investigate the interplay between these local and regional processes in determining the composition and relative abundances of plant species in their natural habitats. The goldenrod beetle (genus Trirhabda) is known to reach extremely high population densities and to decimate its host plant, tall goldenrod (Solidago altissima). S. altissima is a competitive dominant, so this intense herbivory substantially reduces the competitive stress on other plant species, leading to dramatic changes in their abundances. I will use data on the Trirhabda-Solidago system to test the ability of my spatial models to explain patterns of abundances in natural plant populations. This work will comprise a unique examination of the role of spatial scale in shaping species interactions. By bringing together spatial ecological models and field data, my research will foster the development of mathematical methods that can be widely applied in the environmental sciences.