In lowland areas of the world and high-altitude European mountains, the species compositions, body sizes, and wing forms of carabid beetles are known to change according to vegetation structures. However, little is known regarding the assemblage structure and habitat associations of carabid beetles in Japanese alpine-subalpine areas. We surveyed carabid beetles in four habitats (snow beds, alpine meadows, Pinus scrub, and fell-fields) in the alpine-subalpine zone on Mt. Hakusan, Japan. We surveyed carabid beetles six times between mid-July and late September. Nonmetric multidimensional scaling (NMDS) and analysis of similarities (ANOSIM) revealed three distinct carabid beetle assemblages in snow beds and alpine meadows, Pinus scrub, and fell-fields. The carabid beetle assemblages in the four habitats consisted predominantly of small and/or wingless species with differential spatiotemporal variability in abundance. Biota-environment (BIO-ENV) analyses showed that the percentage coverage by Pinus scrub, soil water content, and ground surface temperature were among the most significant variables affecting carabid beetle compositions. Given their small sizes and reduced wings, which are characteristic traits for limited mobility, and high-level habitat specificity, carabid beetles in the alpine-subalpine zone may serve as an important target group to monitor the impacts of global environmental change on mountain ecosystems.

Abstract. Rural biodiversity in East Asia is at risk due to the loss of habitat diversity, and good indicators are needed to evaluate diverse habitats in rural landscapes. We examined whether the higher taxa (classes and orders) of soil invertebrates discriminated among several types of secondary forests such as broad-leaved deciduous forests, conifer forests and bamboo forests, primary forests, grasslands and/or wetlands, better than species assemblages of a well-established indicator, ground beetles (Coleoptera, Carabidae and/or Staphylinidae), in three East Asian regions (Japan, South Korea and the Russian Far East). We collected soil invertebrates with pitfall traps and used community composition and an ordination technique to test their performance as indicators. In Japan, the higher taxa of soil invertebrates discriminated finely among a wide range of habitats, and soil moisture seemed to be an important factor underlying habitat arrangement by these taxa along an ordination axis. While species assemblages of ground beetles detected large faunal differences among grasslands, wetlands and a composite group of three forest-type habitats (oak, conifer and bamboo forests), it failed to discriminate among any of the three forest-type habitats. When the analysis included only these types of forests, ground beetles were found to be able to discriminate finely among them, indicating limited performance in relation to the range of habitats 164 S.-I. TANABE ET AL.covered. In the other two countries, the higher taxa of soil invertebrates showed a performance similar to that of species assemblages of ground beetles, possibly because of the narrow range of habitats analyzed. We conclude that the higher taxa of soil invertebrates are an effective tool for assessing the diversity of rural habitats across the East Asian region, where taxonomic knowledge at the species level is still insufficient. Our results may be applied broadly to other regions where agricultural intensification and land abandonment have caused quantitative and qualitative changes in rural landscapes.

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