To identify the key effects of human disturbance on terrestrial ecosystems is a major issue in the contemporary conservation. We compared the community structure of ground beetles among different forest patch sizes according to the different forest types. In addition, we examined how different functional groups and species responded to patch size, and habitat and geographical variables. We sampled ground beetles in 9 continuous forests and 18 patches including 6 deciduous, 6 Korean pine, and 6 Japanese red pine. Ground beetles were collected using 5 pitfall traps in each site, and replaced every month during May to October in 2013. Individual-based rarefaction curves indicated that higher species richness was found in continuous forests than forest patches irrespective of the forest types. Positive relationships were found between forest patch size and species richness of each functional group associated with forest habitat. When all patch size, geographical, and habitat variables were considered simultaneously for multiple regressions, patch size, longitude, latitude, elevation, organic matter, and litter depth were generally selected as significant predictor variables of the abundance and species richness of forest specialists, brachypterous, dimorphic, and large-bodied species, although longitude was only selected as a best predictor for 27 study sites in MRT. In conclusion, decreasing patch size is a major factor to the loss of biodiversity for ground beetles. To reduce biodiversity loss caused by habitat fragmentation, therefore, protecting as large as old-growth forests and improving habitat quality are critical for the biodiversity conservation and enhancement.

The effects of thinning on community diversity of wood-boring beetles were examined in Japanese Larch (Larix kaempferi) forest in In-je, South Korea in 2013. Three study sites were selected and thinning in the plots was conducted in 2010, spring 2012, and autumn 2012, respectively. Wood-boring beetles were collected every week using the 12-unit Lindgren multi-funnel traps with pheromone lure (Ipsdienol +50/-50 40mg, Ipsenol +50/-50 40mg) from mid-April to early November. Total 5 families (Cerambycidae, Curculionidae, Dryophthoridae, Scolytidae, Platypodidae), 62 species, and 26,638 individuals were collected. Diversity indices were 2.08, 2.02 and 0.76, and evenness indices were 0.55, 0.49 and 0.19 in 2010, spring 2012 and autumn 2012 thinning area, respectively. Among wood-boring beetles, the number of species of bark and ambrosia beetles were accounted for 44.4, 41.9 and 46.3% in 2010, spring 2012 and autumn 2012 thinning area, respectively. The number of individuals of bark and ambrosia beetles were accounted for 86.9, 82.2 and 98.4% in 2010, spring 2012 and autumn 2012 thinning area, respectively. Our results showed that the density of wood-boring beetles was the highest in the most recent thinning area, suggesting that thinning timing can influenced on the abundance of bark and ambrosia beetles. Among them, Ips subelongatus, I. acuminatus, and I. sexdentatus are species that mainly attack Japanese Larch. Ips subelongatus emerged faster than others and was the most dominant species.

The present study is aimed to evaluate forest health in a fragmented urban forest using insects which are rarely used for evaluation of forest health. It is supposed that forest would be health if insect community in an urban forest is similar to that in healthy forests. Ants (Formicidae) and ground beetles (Carabidae) surveyed by pitfall trap method in the Hongneung forest located in the urban area of Seoul were compared with those in the Gwangneung forest. The Gwangneung forest is supposed to be health due to its high biodiversity and well-conserved nature. Ants of the Hongneung forest was much more abundant compared with those of the Gwangneung forest. However, ground beetles showed the opposite patterns; much more abundant in the Gwangneung forest than in the Hongneung forest. Species richness was higher in the Gwangneung forest than in the Hongneung forest, but species diversity was higher in the Hongneung forest. This dominance decreased species diversity in the Gwangneung forest. Thus, characteristics of insect community in the Hongneung forest were greatly different with that in the Gwangneung forest. This great difference of insect communities between the target and reference sites may indicate whether the Hongneung forest would not be health according to the working hypothesis, or may indicate simply the characteristic of the fragmented urban forest. In order to determine the significant decision, the repetitive studies are needed on this regard.

The wood-boring and bark beetle (Cerambycidae, Curculionidae, Scolytinae) community in Korean white pine, Pinus koraiensis Sieb. & Zucc., forests was surveyed using Malaise traps in 2007. A total of 1,669 wood-boring and bark beetles were collected, including 193 cerambycids from 16 species, 221 curculionids from 21 species, and 1,255 scolydid beetles from 6 species, of which the dominant species was the ambrosia beetle Xyleborus mutilatus Blandford. Ranked by order of population size, the wood-boring and bark beetle community in Korean white pine showed high dominance by one species of Scolytinae, suggesting the community was unstable and had low biological diversity. Thinning in Korean white pine forests influenced the abundance of bark and ambrosia beetles, whose populations in particular stands increased 1 year after thinning, and then decreased the following year.

We've collected litter-dwelling predatory arthropods (spiders and carabid beetles) by using pitfall traps at four different fire intensity treatment areas (control, ground fire, canopy fire, and canopy fire with plantation) at four different regional areas in 2005. We analyzed the arthropod community structures with PC-Ord for the difference of arthropod community among the various fire intensity treatments and control. Our objective was to verify if there was any difference between fired areas and non fired area (control) and between canopy fire with plantation and canopy fire without plantation. From our arthropod community structures, we found there was distinct community composition difference between fired areas and non-fired area as well as between control and canopy fire treatment with plantation or non-plantation. However, we are not sure yet that there was any distinct difference between control and ground fire treatments. Our results from the multivariate analysis, Non-parametric Multidimensional Scaling ordination, could be relatively conclude that the main difference of arthropod community between fired areas and non-fired areal and canopy fire with plantation or non-plantation was caused from the difference of arthropod habitat pattern such as litter depth, litter volumem, CWD cover or volume, and et. al. When we compared to control and other treatments, we could also conclude that the canopy fire treatment with non-plantation was relatively closed to control than the canopy fire treatment with plantation.