Although Carabidae is among the best-studied families of beetles in Europe from the faunistic point of view, there is still a lack of available information on the ecological requirements of the particular carabid species. The habitat preferences that determine the distribution of species are largely influenced by habitat structure and microclimate. In addition to other factors, these habitat parameters are influenced by the nature of the vegetation. Therefore, our study investigated the influence of tree species on carabid beetle communities. We conducted the research at 9 stands in the Borova Hora Arboretum (Zvolen, Central Slovakia). Each studied site represents a monoculture of one of nine tree species. At each site, some soil and leaf litter attributes (pH, conductivity, and content of H, C, N and P) were evaluated. Ground beetles were collected by pitfall trapping during the vegetation periods in 2008–2011. In total, 3012 individuals of 29 species were obtained. Significant differences in the total dynamic activity and species richness of the carabid beetle communities among the compared forest stands were revealed. The results of the research confirmed statistically significant relationships among 1) the soil conductivity and both the richness and Shannon diversity of the ground beetle communities, 2) the litter and soil N content and richness, the Shannon diversity and the species composition of the ground beetle communities. The Shannon diversity and richness were negatively related to the soil conductivity and positively related with the N content. Our research showed that dominant tree species indirectly influence diversity and composition of carabid communities via the soil properties.

Influence of tree species and soil properties on ground beetle (Coleoptera: Carabidae) communities

The positive effects of habitat heterogeneity on biodiversity are well established, but it is unclear how the diversity of less frequently studied but ecologically important taxa such as harvestmen (Opiliones) may vary across habitat boundaries generated by fine-scale traditional land-use We investigated how harvestmen community metrics (composition, abundance, and diversity) varied across forest-meadow ecotones in a protected and naturally highly biodiverse karst region where biodiversity conservation plays an important role We sampled harvestmen across forest edges adjacent to hay meadows in the Veľka Fatra Mts (Central Slovakia) during two vegetation seasons using pitfall traps In total, 13 species from 4 families were collected The total number of captured harvestmen was greatest in forests and lowest in meadows and species composition varied between these two habitats (with forest edges forming a transitional community) Species diversity (exponential of Shannon’s H´) was marginally greater within forest edges compared to forest and meadow habitats Harvestmen epigeic activity-density (an abundance proxy) was correlated positively with tree canopy cover, and negatively with the cover of herbaceous layer Our findings have implications for biodiversity conservation as they highlight the importance of forest habitats for the conservation of understudied taxa such as harvestmen in heterogenous landscapes modified by humans

Harvestmen (Opiliones) community structure varies across forest-meadow ecotones in a biodiverse karst region

Carabid beetles, predatory insects, are abundant in forests and sensitive to environmental changes. The distribution patterns and diversity of carabid beetles in several natural forests were studied to provide a basis for evaluating the importance of a forest in the protection of carabid beetle diversity. Carabids were captured by pitfall traps during their seasonal activity from 2012 to 2013 in a poplar-birch forest, ash-walnut forest and broad-leaved Korean pine forest. A total of 5252 individuals, representing 21 species, were collected. Carabid abundance was highest in the broad-leaved Korean pine forest and lowest in the ash-walnut forest. Carabus billbergi Mannerheim and Pterostichus pertinax (Tschitscherine) were the dominant beetle species in each stand. Carabus canaliculatus Adams was dominant in the poplar-birch and ash-walnut forests, and Leistus niger Gebler was dominant in the ash-walnut forest. The carabids were affected differently by stand factors. C. billbergi and P. pertinax was positively correlated with mean DBH. C. canaliculatus and L. niger were not positively correlated with any stand factors. The broad-leaved Korean pine forest with greater age, large DBH and thick leaf litter fostered a high diversity of carabid species. The main yearly activity period for most carabids was during July. Different carabid species responded differently to seasonality, and the activity period of several species was relatively late (August) in the year.

The distribution patterns and temporal dynamics of carabid beetles (Coleoptera: Carabidae) in the forests of Jiaohe, Jilin Province, China

The study presents a comparison between the diversity of the carabid beetles taxocoenoses and their spatial distribution in different forest types of high conservation value in Strandzha (8 sites), the Rhodopes (4 sites) and Belasitsa (6 sites) mountains. The diversity indices have demonstrated the highest species richness and the highest diversity values in the riverside sites of Strandzha Mountain. The lowest species richness has been found in the tertiary relict forest of oriental beech with undergrowth of rhododendron (Strandzha Mountain) and in the centuryold sweet chestnut forest (Belasitsa Mountain). The lowest values of diversity and evenness have been found in the beech forest sites in Strandzha and the Rhodopes due to the prevalence of the Aptinus species. This low diversity is a natural condition for the studied sites. The classification of the ground beetles complexes from the studied sites by similarity indices and TWINSPAN has been made. A high level of dissimilarity among the sites has been found, showing unique species composition and abundance models in each site. Carabid beetles taxocoenoses in the forests of Strandzha Mountain have shown a low similarity level by species composition and abundance even in the range of the same mountain. Indicator species have been shown. The ordination of the carabid complexes has showed that the sites have been distributed continuously along two significant gradients. The first gradient has been found to be the altitude (probably due to the temperature conditions) in a combination with the hydrological regime. The second significant gradient probably has been under the complex influence of the climate conditions and vegetation type. Carabidae; diversity; conservation; Bulgaria.

Rumyana Kostova

Papers

Ground beetles (Coleoptera Carabidae) diversity patterns in forest habitats of high conservation value, Southern Bulgaria