THE EFFECT OF FRAGMENTATION AND INTENSIVE MANAGEMENT ON CARABID BEETLES IN CONIFEROUS FOREST

We studied the effects of forest fragmentation and management practices on carabid beetle (Coleoptera: Carabidae) assemblages in the Japanese red pine forests of Naju City, South Korea. A total of 2,058 carabid individuals, representing 15 species, were collected by pitfall trapping from May to September 2010 in three forest types: native forest (relatively undisturbed forest), managed forest (planted trees with clear-cutting of the herb layer), and forest patch (fragmented forest). We showed that the different forest types differed significantly in terms of their carabid assemblages. The managed forest had the most distinct assemblage, with a lower species richness and abundance than the other two forest types. Although forest fragmentation did not significantly affect the species richness of carabid beetle assemblages, the abundance of some carabid beetles (forest specialists and large-sized species) was significantly altered by forest fragmentation and intensive forest management. Sub-tree layer and herb cover were the strongest environmental variables determining the carabid assemblage composition. Forest fragmentation is an inevitable change in landscape structure, particularly in urbanized and pre-urban areas, and it constitutes a threat to biodiversity through landscape homogenization. Therefore, it is necessary to identify appropriate management practices, designed to minimize the damage caused by the loss and modification of natural habitats, together with maintenance and enhancement of the biodiversity in urban areas.