EAGER: Integrating Succession Into Metacommunity Theory: Diversity-Age Relationships Across Temporal and Spatial Scales

本研究旨在整合演替和元群落生态学的基本生态学概念。演替被定义为群落中存在的物种类型和数量（物种多样性）随时间的变化。元群落是一组相互作用的群落，它们通过多个潜在相互作用的物种的个体运动（分散）联系在一起。元群落研究的重点是物种在本地群落中的扩散在决定物种多样性跨空间尺度（本地和区域）中的作用。然而，群落演替阶段在构建元群落物种多样性中的作用尚不清楚。本研究将探讨池龄（即群落演替阶段）对河狸池元群落物种多样性和食物网大小的影响。由于许多海狸池塘本质上是恢复的生态系统，因此本研究的结果将对恢复生态学具有重要意义，因为它表明了群落演替阶段在恢复过程中的相关性。此外，这些发现将有助于决定目前在美国和欧洲广泛进行的海狸重新引入工作的地点和时间。该项目还将为一名博士生和几名本科生提供研究培训。此次外展活动将使一所农村高中的50名学生受益。PI将与一名高中学生教师开发一个实验室和教学模块，向学生介绍生态演替和海狸干扰。研究将在不同演替阶段解决以下问题：1)物种多样性和性状组成对栖息地年龄和当地环境的响应更强烈，还是对区域尺度上的过程的响应更强烈？2)生态系统年龄是否影响食物链长度？如果是这样，这是区域驱动因素（如新物种的殖民化）还是本地驱动因素（如池塘大小、生产力）的结果，还是两者兼而有之？研究者将通过分析海狸池元群落（三个流域的溪流和海狸形成的池塘）的群落和物种特征多样性、环境栖息地特性（水化学、面积、最大深度和流速）、性状-环境关系以及顶端捕食者的营养地位来解决这些问题。

This study seeks to integrate the fundamental ecological concept of succession and metacommunity ecology. Succession is defined as changes over time in the type and number of species (species diversity) present in a community. A metacommunity is a set of interacting communities, which are linked by the movement of individuals (dispersal) of multiple potentially interacting species. Metacommunity studies have focused on the role of species dispersal among local communities in determining species diversity across spatial scales (local and regional). However, the role of the community successional stage in structuring species diversity within metacommunities is not well understood. The study will investigate the role of pond age (i.e., community successional stage) on the species diversity and the size of food webs of metacommunities of beaver ponds. Since many beaver ponds are essentially restored ecosystems, the results of this study will be significant for restoration ecology, by indicating how relevant the successional stage of the community is within the restoration process. In addition, the findings will facilitate decisions about the location and timing of beaver reintroduction efforts that are currently widespread in the US and Europe. This project will also provide research training for one doctoral student and several undergraduate students. The outreach activities will benefit 50 students from a rural high school. The PI and a high school student teacher will develop a laboratory and teaching module to introduce students to ecological succession and beaver disturbance. The study will address the following questions across different successional stages: 1) Does species diversity and trait composition respond more strongly to habitat age and the local environment, or to processes at the regional scale? 2) Does ecosystem age influence food chain length? If so, is this the result of a regional driver (e.g. colonization of new species) or local driver (e.g., pond size, productivity), or both? The investigator will address these questions by analyzing community and species trait diversity, environmental habitat properties (water chemistry, area, maximum depth and flow rate), trait-environment relationships, and the trophic position of apex predators in replicated studies of beaver pond metacommunities (streams and beaver-formed ponds of three watersheds).