DISSERTATION RESEARCH: How Land Cover and Landscape Connectivity Interact to Determine Species Ranges

找到协调人类和野生动物栖息地需求的方法，对于保护物种多样性至关重要。本研究的目的是探讨在人类主导的景观土地利用如何影响野生物种的发生。 野生物种的这些“分布”取决于两种类型的栖息地的可用性：种群可以生长和持续的栖息地，以及连接种群以允许扩散的栖息地。 土地使用的变化会影响这两种类型的栖息地，但大多数研究只考虑了第一种类型。 这项研究的重点是如何栖息地连接影响青蛙种群的增长和生存。 在这样做时，它将为研究生和本科生提供研究培训。 这项研究的结果将用于为小学生制作教育材料，他们将了解栖息地的连通性如何影响动物的扩散。 研究人员将与迈阿密大学的赫夫纳自然历史博物馆合作，创建一个展示，解释人类土地使用模式如何影响野生动物。 最后，为这项研究开发的方法可能会提供物种管理plannes.Specifically的基础上，本项目的目标是测试的假设，景观连通性解释的差异，在一个物种？已实现的分布与潜在的分布，基于合适的栖息地的可用性。利用蟋蟀蛙（Acris blanchardi）作为一个模型系统，研究人员将解决以下目标：（1）评估哪些土地使用和环境因素对栖息地的适宜性最重要，并预测物种的存在，（2）确定目前的山脉东部边缘，以及蟋蟀蛙的实际分布与适宜栖息地的分布是否存在差异（潜在分布），（3）评估是否梯度景观连接从内部到边缘的范围可以解释差异实现和潜在的分布。目标1和2将使用生态位建模和地面实况调查来解决。生态位模型将使用以前调查的存在数据，并包括气候和土地使用数据层。目标3将通过将生态位模型的结果结合到基于图论的景观连通性分析中来解决。将在范围内部、范围边缘和范围外部之间比较连通性。由于最近蟋蟀青蛙范围边界的缩小和扩大，调查人员预测目前范围以外的合适栖息地。低水平的景观连接范围边界和范围外的预测解释为什么蟋蟀青蛙无法占据其整个潜在的范围。

Finding ways to reconcile the habitat needs of people with those of wildlife is of great importance for preservation of species diversity. The objective of this study is to examine how land-use in a human dominated landscape affects where wild species occur. These "distributions" of wild species depend on availability of two types of habitat: habitat where populations can grow and persist, and habitat that connects populations to allow for dispersal. Changes in land-use can affect both types of habitat, yet most research has considered just the first type. This study focuses on how habitat connectivity impacts the growth and survival of frog populations. In doing so, it will provide research training for graduate and undergraduate students. Findings from this study will be used to create educational materials for elementary school students, who will learn about how habitat connectivity affects animal dispersal. The investigators will collaborate with the Hefner Museum of Natural History at Miami University to create a display explaining how patterns of human land-use affect wildlife. Finally, the methodology developed for this study may provide the basis for species management plans.Specifically, the goal of this project is to test the hypothesis that landscape connectivity explains discrepancies in a species? realized versus potential distribution, based on availability of suitable habitat. Using cricket frogs (Acris blanchardi) as a model system, investigators will address the following aims: (1) assess which land-use and environmental factors are most important for habitat suitability and are predictive of species presence, (2) determine the current eastern edge of the range and whether there is a discrepancy between the actual cricket frog distribution and the distribution of suitable habitat (potential distribution), and (3) assess whether a gradient in landscape connectivity from the interior to edge of the range can explain differences in realized and potential distributions. Aims 1 and 2 will be addressed using ecological niche modeling and ground-truthing surveys. The niche model will use presence data from previous surveys and include both climatic and land-use data layers. Aim 3 will be addressed by incorporating niche model results in landscape connectivity analyses based on graph theory. Connectivity will be compared between the interior of the range, the range edge, and outside the range. Due to recent contraction and expansion of the cricket frog range boundary, investigators predict areas of suitable habitat outside the current range. Low levels of landscape connectivity at the range boundary and outside the range are predicted to explain why cricket frogs are unable to occupy their entire potential range.