Hidden collembolan forest habitat: Specificity and species diversity of Collembola communities on fallen branches

Abstract

Collembola are an important class of arthropods in forest ecosystems. However, research on these organisms has traditionally focused on soil and litter layers while largely neglecting other potential habitats. Therefore, this study explored potential habitats of Collembola beyond those traditionally investigated. We hypothesized that fallen branches, which are widespread on the forest floor but have seldom been studied as habitats for collembolan communities, represent a potentially important microhabitat. We compared collembolan communities in leaf litter and soil and on fallen branches at three decomposition stages (early, middle, and late) in evergreen broad-leaved forests in the warm temperate zone of Japan. We found that Collembola communities hosted in middle- and late-stage fallen branches were more abundant and diverse than those in the soil and litter layers. In addition, Neanuridae, Hypogastruridae, and Odontellidae members mainly colonized fallen branches. These results indicate that the species diversity and community composition of Collembola differed significantly among vertical microhabitats, with the previously overlooked habitat of fallen branches supporting distinct Collembola communities and thus enhancing forest biodiversity.