This study investigated the relative influences of environmental, spatial, and historical factors, including the island‐specific history of land connectivity, on bat assemblages in the Japanese Archipelago. We collected bat distribution data from 1408 studies and assigned them to Japan's First Standard Grid (approximately 6400 km2). Japanese bat assemblages were analyzed at two scales: the entire Japanese Archipelago comprised 16 islands and exclusively the four main islands. At first, we calculated taxonomic and functional total beta diversity (βtotal) by Jaccard pairwise dissimilarity and then divided this into turnover (βrepl) and richness‐difference (βrich) components. We conducted hierarchical clustering of taxonomic beta diversity to examine the influence of the two representative sea straits, Tsugaru and Tokara, which are considered biogeographical borders. Variation partitioning was conducted to evaluate the relative effects of the three factors on the beta diversity. Clustering revealed that the Tokara Strait bordered the two major clades; however, the Tsugaru Strait did not act as a biogeographical border for bats. In the variation partitioning, shared fraction between spatial and historical factors significantly explained taxonomic and functional βtotal and taxonomic βrepl at the entire archipelago scale, but not at the four main islands scale extending only Tsugaru Strait but not Tokara Strait. Pure environmental factors significantly explained functional βtotal at both scales and taxonomic βtotal only at the four main islands scale. These results suggest that spatial and historical factors are more pronounced in biogeographical borders, primarily structuring assemblage composition at the entire archipelago scale, especially in taxonomic dimension. However, current environmental factors primarily shape the assemblage composition of Japanese bats at the main island scale. The difference in results between the two scales highlights that the primary processes governing assemblages of both dimensions depend on the quality of the dispersal barriers between terrestrial and aquatic barriers for bats.

中文翻译：

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环境、历史和空间过程对日本蝙蝠组合的分类和功能β多样性的尺度依赖性影响

本研究调查了环境、空间和历史因素（包括岛屿特定的陆地连通性历史）对日本列岛蝙蝠群落的相对影响。我们从 1408 项研究中收集了蝙蝠分布数据，并将它们分配给日本第一个标准网格（约 6400 公里）2）。日本蝙蝠群落从两个层面进行了分析：整个日本列岛由 16 个岛屿组成，其中仅包括四个主要岛屿。首先，我们计算了分类学和功能性总β多样性（β全部的）通过 Jaccard 成对差异，然后将其除以营业额（β重复）和丰富度差异（β富有的） 成分。我们对分类β多样性进行了层次聚类，以研究两个代表性海峡津轻海峡和吐卡拉海峡（这两个海峡被认为是生物地理边界）的影响。进行变异分配以评估三个因素对β多样性的相对影响。聚类显示吐噶喇海峡与两个主要分支接壤；然而，津轻海峡并不是蝙蝠的生物地理边界。在变异划分中，空间和历史因素之间的共享分数显着解释了分类和功能β全部的和分类学β重复整个群岛规模，但不是仅延伸津轻海峡而不是吐噶喇海峡的四个主岛规模。纯环境因素显着解释了功能性β全部的在尺度和分类学上β全部的仅在四个主要岛屿规模上。这些结果表明，空间和历史因素在生物地理边界中更为明显，主要是在整个群岛规模上构建组合组成，特别是在分类维度上。然而，当前的环境因素主要塑造了日本蝙蝠在主岛尺度上的聚集组成。两个尺度之间结果的差异凸显出，控制两个维度组合的主要过程取决于蝙蝠的陆地和水生屏障之间的扩散屏障的质量。