Dissertation Research: The Roles of Local and Metapopulation Forces in Determining Regional Scale Aphid Population Dynamics

莫里斯9801089许多生物的分布范围是由通过迁徙连接的适宜栖息地斑块中的种群集合组成的。 这样的集合被称为集合种群。 为了理解和预测集合种群将如何随着时间的推移，有必要了解这两个过程分别影响每个种群（例如捕食者-猎物关系）和过程影响补丁之间的迁移。 对蚜虫的初步研究表明，捕食压力和斑块分布影响集合种群动态。 两年多来收集的观测和实验数据被用来拟合描述A。卢根蒂斯系统 该模型将被用来预测的捕食者密度和补丁的安排，这将是在现场进行的大规模操作的结果。 拟议的操作将是第一个明确的实验测试的作用，迁移控制集合种群动态。 当模拟模型能够准确预测大规模操作的结果时，它将被用来回答两个密切相关的问题。首先，在什么条件下影响斑块间迁移的因素在集合种群动态中起重要作用？ 第二，在什么条件下斑块内的过程变得如此重要，以掩盖移民的影响，在确定集合种群动态？这项研究将提供重要的实验证据，迁移在确定集合种群动态的重要性。 虽然大量的理论预测迁移率在决定集合种群动态方面的关键作用，但该理论在很大程度上未经检验。集合种群模型在物种管理和保护计划中得到了广泛的应用。 除了提供实验证据证明迁移确实在确定集合种群动态方面发挥了重要作用外，本研究还将探讨斑块内过程和迁移在各种条件下的相对重要性如何变化。 在这样做的过程中，它将朝着预测大规模的人口动态何时可以预测的基础上的补丁过程，迁移和灭绝率单独的信息，以及何时更详细的信息在这两个尺度是必要的。

Morris9801089The range of many organisms consists of collections of populations in suitable habitat patches connected through migration. Such collections are called metapopulations. In order to understand and predict how metapopulations will behave over time it is necessary to understand both processes affecting each of the populations separately (e.g. predator-prey relations) and processes affecting migration between patches. Preliminary studies on the aphid, Aphis lugentis, reveal that both predation pressure and patch distribution affect metapopulation dynamics. Observational and experimental data collected over two years is being used to fit a simulation model describing the A. lugentis system. The model will be used to predict the results of large-scale manipulations of predator density and patch arrangement which will be carried out in the field. The proposed manipulations will be the first explicit experimental test of the role of migration in controlling metapopulation dynamics. When the simulation model is able to accurately predict the results of the large-scale manipulations it will be used to answer two closely related questions. First, under what conditions do factors affecting migration between patches play an important role in metapopulation dynamics? Second, under what conditions do within patch processes become so important as to mask the affects of migration in determining metapopulation dynamics? This study will provide crucial experimental evidence for the importance of migration in determining metapopulation dynamics. While a great deal of theory predicts a critical role for migration rates in determining metapopulation dynamics that theory has gone largely untested. Nevertheless metapopulation models are widely used in species management and conservation plans. Beyond providing experimental evidence that migration does indeed play an important role in determining metapopulation dynamics, this study will explore how the relative importance of within patch processes and migration change under a variety of conditions. In so doing it will take a large step towards predicting when large-scale population dynamics can be predicted based on information about within patch processes alone, migration and extinction rates alone, and when more detailed information at both scales is necessary.