ABSTRACT: Ecological communities are jointly structured by dispersal, density-independent responses to environmental conditions, and density-dependent biotic interactions. Metacommunity ecology provides a framework for understanding how these processes combine to determine community seagrass meadows along the British Columbia coast. We tested the hypothesis that eelgrass Zostera marina L. epifaunal invertebrate assemblages are influenced by local environmental conditions but that high dispersal rates at larger spatial scales dampen the effects of environmental differences. We used hierarchical joint species distribution modelling to understand the contribution of environmental conditions, spatial distance between meadows, and species co-occurrences to epifaunal invertebrate abundance and distribution across the region. We found that patterns of taxonomic compositional similarity among meadows were inconsistent with dispersal limitation, and meadows in the same region were often no more similar to each other than meadows over 1000 km away. Abiotic environmental conditions (temperature, dissolved oxygen) explained a small fraction of variation in taxonomic abundance patterns across the region. We found novel co-occurrence patterns among taxa that could not be explained by shared responses to environmental gradients, suggesting the possibility that interspecific interactions influence seagrass invertebrate abundance and distribution. Our results suggest that biodiversity and ecosystem functions provided by seagrass meadows reflect ecological processes occurring both within meadows and across seascapes and that management of eelgrass habitat for biodiversity may be most effective when both local and regional processes are considered.

中文翻译：

---

超越一个单一的补丁：本地和区域过程解释了海草表生真菌群落中的多样性模式

摘要：生态群落是由分散，对环境条件的密度独立响应以及密度依赖性生物相互作用共同构成的。元社区生态学提供了一个框架，用于了解这些过程如何结合起来以确定不列颠哥伦比亚省沿岸的社区海草草甸。我们测试了鳗el Zostera码头的假说表生乳杆菌无脊椎动物组合受当地环境条件的影响，但在较大空间尺度上的高分散率会减弱环境差异的影响。我们使用分层联合物种分布模型来了解环境条件，草地之间的空间距离以及物种共生对表层无脊椎动物的丰度和分布的贡献。我们发现草甸之间的分类学组成相似性模式与扩散限制不一致，并且同一地区的草甸彼此之间的相似性通常不超过1000公里以外的草甸。非生物环境条件（温度，溶解氧）解释了该地区生物分类丰度模式的一小部分变化。我们发现分类群之间的新共生模式无法用对环境梯度的共同响应来解释，这表明种间相互作用可能影响海草无脊椎动物的丰度和分布。我们的结果表明，海草草甸提供的生物多样性和生态系统功能反映了草甸内部和整个海景中都发生的生态过程，并且在考虑本地和区域过程的情况下，对鳗草栖息地进行生物多样性管理可能是最有效的。