Dissertation Research: Interspecific Interactions in Stage Structured Population Models: The Effects of Herbivores and Pollinators on Trillium grandiflorum

建议0105000DIG：阶段性结构种群模型中的种间相互作用：食草动物和传粉者对延龄草的影响苏珊·卡利兹，蒂凡尼·奈特植物种群的增长速度取决于它与食草动物和传粉者相互作用的强度，以及植物生命周期中发生这些相互作用的阶段。因此，植物种群之间与食草动物和传粉者相互作用的大小的不同可能导致自然植物种群之间的生长速度的差异。如果开花植物密度高的种群对食草动物和传粉者都更具吸引力，那么它们与食草动物和传粉者的相互作用的大小可能会随着植物种群的增长或下降而发生确定性的变化。我收集了12个种群的初步数据，延龄草是一种多年生森林草本植物。它与哺乳动物食草动物白尾鹿和昆虫传粉者熊蜂的相互作用在这些种群中差异很大，这些相互作用主要影响植物生命周期的繁殖阶段。在操纵植物密度的先导实验中，发现植物-食草动物和植物-传粉者相互作用的大小都发生了显著变化。在这项拟议的工作中，我将量化由于食草动物和传粉者相互作用的变化而导致的种群间的变化量。此外，在几个种群中，我将通过实验操纵植物密度，以更全面地量化草食动物和传粉者对延龄草存活、生长和繁殖力的密度依赖影响。我将使用一个模型框架来综合所有这些信息，并评估物种间相互作用的变化对植物种群生长速度的影响。

Proposal 0105000DIG: Interspecific interactions in stage structured population models: The effects of herbivores and pollinators on Trillium grandiflorumSusan Kalisz , Tiffany KnightThe growth rate of a plant population depends on the strength of its interactions with herbivores and pollinators, as well as the stage in the plant life-cycle in which these interactions take place. Thus, variation in the magnitude of interactions with herbivores and pollinators among plant populations can cause variation in the rates of growth among natural plant populations. If populations that have a high density of flowering plants are more attractive to both herbivores and pollinators, then the magnitude of their interactions with both herbivores and pollinators may be expected to change deterministically as plant populations grow or decline in time. I have collected preliminary data on 12 populations of Trillium grandiflorum, a perennial forest herb. The magnitude of its interactions with its mammalian herbivore, white tailed deer, and insect pollinator, bumblebees, vary highly among these populations, and these interactions primarily influence the reproductive stage in the plant life-cycle. In a pilot experiment that manipulated plant density, significant changes in the magnitude of both plant-herbivore and plant-pollinator interactions were found. In this proposed work, I will quantify the amount variation among populations that is caused by variation in herbivore and pollinator interactions. In addition, among several populations, I will experimentally manipulate the plant density to more fully quantify the density-dependent influences of herbivores and pollinators on Trillium survival, growth and fecundity. I will use a modeling framework to synthesize all of this information and assess the effects of changes in interspecific interactions on the growth rate of plant populations.