Many spiders belonging to Enoplognatha Pavesi, 1880 and Parasteatoda Archer, 1946 of Theridiidae were collected with sweep net between shrubs and bushes in the mountain forest during a survey of the mountain spider fauna. Among the spiders collected, male Enoplognatha gramineusa Zhu, 1998 and female Parasteatoda ryukyu (Yoshida 2000) were recognized as newly recorded spiders to Korean spider fauna. The present work describes these two spiders with measurements and morphological illustrations.
The present study was conducted to investigate the differences in managed farming practices, including low-intensive farming, duck farming, and golden apple snail farming, in a rice ecosystem by comparing terrestrial arthropod communities. A total of 75 species from 70 genera belonging to 43 families in 11 orders were identified from 9,622 collected arthropods. Araneae, Hemiptera, and Coleoptera were the richest taxa. Collembola was the most abundant, followed by Diptera, Hemiptera, and Araneae. Bray- Curtis similarity among the farming practices was very high (76.7%). The biodiversity of each farming practice showed a similar seasonality pattern. The richest species group was the predators, followed by the herbivores. The species richness and diversity of ecologically functional groups among the farming practices were not statistically significant, except for the abundance of predators in golden apple snail farming. The biodiversity seasonality of ecological functional groups in each farming practice showed similar patterns. The biomass of Araneae, Hemiptera, Coleoptera, and Diptera was greater than the other taxa, in general. The biomass of each ecological functional group showed little difference and the biomass fluctuation patterns in each farming practice were almost the same. Collectively, the community structures and biodiversity of terrestrial arthropods among the farming practices in the present study were not different. The present study may contribute to sustain rich biodiversity in irrigated rice fields and to advanced studies of food webs or energy flow structures in rice fields for ecological and sustainable agriculture.
In recent, habitat fragmentation is one of the major factors to threat to biodiversity loss, because habitat fragmentation caused by urbanization and land-use change affect reducing of habitat amount and changing of environmental condition. In particular, increasing of forest edges by habitat fragmentation cause changing of microclimate and distribution of organisms in forest. This study was conducted to examine the distributional patterns of ground beetle assemblages along forestedge- crop gradients in Hoengseong-gun, Gangwon-do. We selected 8 study sites as line gradients from forest interior to crop (+80m, +40m, +20m, 0m, -20m, -40m, -80m). Ground beetles were collected by pitfall traps from May to October in 2012. A total of 61 species were identified from 3,739 collected beetles. Species richness was the highest at forest edge (GLM with Tukey’s test, F6, 49=2.56, P=0.031). Although abundance was higher at both forest interior and edge, but not showed statistical significance (F6, 49=2.06, P=0.076). Species composition of forest interiors were significantly different from forest exteriors (crops) by non-metric multidimensional scaling (NMDS) and cluster analysis with similarity profile test (SIMPROF), while forest edges showed intermediate characteristics. Although our study sites may not represent the overall Korean forest, we confirmed that forest edges are important habitats for generalists and open-habitat species as well as forest specialists. In conclusion, management of both forest edge and its surroundings are needed to conserve biodiversity in forest,
Environmental changes such as land-use change including reclamation cause effects on the ecosystem seriously. Present study investigated community structure of hemipterans in several reclaimed lands from western coast of South Korea in 2010, because among arthropods, hemipterans are more influenced by land-use change which caused the change of dominant plants. Six reclaimed lands were selected for our study based on the ages of reclaimed land (0, 5, 12, 16, 20, and 31 years). Dominant plant species of reclaimed lands were belonging to Poaceae, Phragmites communis and Oryza sativa in Yeongsangan II, Sabkyocheon, Geumgan I and Gyehwado, Secale cereale in Seokmun, and Imperata cylindrica and Calamagrostis epigeios in Sihwa. A total of 31 species in 10 families were identified from 4475 collected hemipterans. In Sihwa, Shannon’s diversity was very low compared to other 5 reclaimed lands due to dominance of Paromius exiguus. Because I. cylindrica and C. epigeios were 1st and 2nd host plants of P. exiguus (2824 individuals only collected from Sihwa). In multivariate analysis, 6 reclaimed lands grouped into 2 major groups showing 49.8% in Bray-Curtis similarity between 2 groups. From these results, land-use change such as reclamation project may cause the outbreak of insect pests by destruction of ecosystem functions and simplification of plant community, although community structure of hemipterans may be stable over age of land reclamation.
This study was conducted to examine the community structure of ground beetles between coniferous and deciduous forest in rural landscapes along latitudinal gradient, such as Miryang-si, Yeongdong-gun, Icheon-si, and Cheolwon-gun from April to October in 2009. A total of 19 species belonging to 15 genera of 9 subfamilies were identified from 6,253 collected ground beetles. Between forest stands, 14 species belonging to 10 genera of 7 subfamilies were identified from 2,874 ground beetles in coniferous forests and 14 species belonging to 11 genera of 7 subfamilies were identified from 3,379 ground beetles in deciduous forests. Dominant species from 4 regions were Synuchus nitidus (59.4% of total) and Synuchus cyloderus (28.5%) respectively. Analysis of similarity (ANOSIM) showed no difference between forest stands, but it was significantly different among regions. Non-metric multidimensional scaling showed that 8 study sites were divergence to 2 major groups between Miryang-si and the others. Overall, community structure of ground beetles showed no difference between forest stands. In conclusion, rural forests is being discussed about important role in biodiversity conservation such as refuge from human activity, and thus, studies on the community structure of ground beetles in the rural forests will be important to manage the biodiversity in agricultural landscapes, because ground beetles are well known for general predator groups in the ecosystems.