Logging impacts on forest carabid assemblages in Japan

Abstract

We hypothesized that small-area logging (<1 ha) would greatly affect microhabitats of carabid beetles. To test this hypothesis, we studied the carabid assemblages at Kamigamo Experimental Station, Kyoto, Japan, from June 1999 to May 2001. From the analysis of the number of individuals and niche breadth, the numbers of large carnivores (Carabus dehanii Chaudoir, Carabus maiyasanus Bates, and Carabus yaconinus Bates) and large insectivores (Chlaenius posticalis Motschulsky and Haplochlaenius costiger (Chaudoir)) decreased because of logging, whereas the small carabids, Synuchus arcuaticollis (Motschulsky) and Synuchus cycloderus (Bates), may not have been negatively influenced by logging. The mass of the FH layer significantly affected the total number of Pterostichus latemarginatus (Straneo) and marginally affected the number of S. cycloderus. However, soil water content (%) and the mass of the L layer did not affect the total number of individuals in any species. The results of this study imply that (1) the richness of the FH layer and vegetation, that is, the potential food abundance and habitat richness, is involved in determining species richness and the density of the carabid assemblages and (2) even small-area logging may have a negative impact on the density of the large predatory carabids, which are sensitive indicators of forest disturbance.