• Korean journal of applied entomology
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• v.56 no.2
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• pp.121-133
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• 2017

This study was conducted to investigate the community structure of arthropods, including various insect pests and their natural enemies, in walnut orchards. Furthermore, we tried to compare the species richness and community structure of arthropods by three different sampling methods, including beating, funnel trap, and pitfall trap. Arthropods were surveyed in three walnut orchards located at Gimcheon, Buyeo, and Hwaseong in South Korea from May to September, 2016. A total of 408 arthropod species were identified from 4,372 individuals, and 63 species were collected in all study sites. The species richness was the highest in funnel trap, while the abundance was the highest in pitfall trap. The species composition of the insects collected by the beating method was more similar to that of the funnel trap than the pitfall trap. Although the distributions of the economically important pests were different according to the study sites, six species, including Dichocrocis punctiferalis, Pseudaulacaspis pentagona, Gastrolina depressa, Lycorma delicatula, Metcalfa pruinosa, and Pochazia shantungensis, are the potentially important pests in walnut orchards. We also found a variety of predators and parasitoids, which will be important for walnut pest management.

• Korean Journal of Environment and Ecology
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• v.29 no.4
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• pp.539-551
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• 2015

This study was carried out to investigate the changing pattern of forest insect communities in 2013 after harvesting of forest in 2012, and provide a basic data for the method of efficient management for preservation of forest biodiversity. Five types of cutting method in pine tree forest were selected to compare the coleopteran insect communities at Hajang-myeon, Gangwon-do, Korea, in 2013. In this study, we investigated the effects of timber harvest with green-tree retention on coleopteran insects. They were sampled with Lindgren funnel traps for five experimental sites during July to October, 2013. A total of 1,112 individuals in 156 species of 40 families by Lindgren funnel traps. Also, the analysis of coleopteran insects community was performed. Although the difference of density is not prominent among the survey areas in the early stages, it was appeared a tendency to increase in density and abundance of insects in the experimented sites excluding the control areas. Among them, strip clear-cutting area showed a increase of density and abundance in this study.

• Journal of Environmental Science International
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• v.19 no.2
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• pp.185-196
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• 2010

The distribution of benthic macroinvertebrates in Daecheon stream, an urban stream of Busan, was investigated to analyze the community structure of benthic macroinvertebrates. The collection was performed monthly at five(A~E) sites divided into three parts, upper, middle and lower, of stream from January to November, 2004. In physicochemical analysis of environmental factors, water quality parameters such as BOD, COD, conductivity and ABS were relatively increased in sites B and C. Whereas sites A, D and E showed little variations with good water quality parameters. However, water quality parameters in all surveyed sites showed gradual decrease with time toward improvement of water quality. A total of 8,226 individuals including 4 phyla, 6 classes, 9 orders, 302 families and 44 species were identified from five sites. The most dominant group was insect(class Insecta), and order Ephemeroptera and Diptera among insect was the largest member in species(30.6%) and individuals(75.0%) of benthic macroinvertebrates, respectively. The primary dominant species were Gammarus sp. and Ephemera strigata in site A, whereas Chironomus sp. and Brenchiura sowerbyi were dominated commonly in the other sites. In community analysis of benthic macroinvertebrates of Daecheon stream diversity index showed relatively low values, whereas dominance index was significantly high. Diversity index was the highest in site A, whereas the dominance index was the highest in site B. However, diversity index showed gradual increase with time showing adverse mode in dominance index. From these results, it can be suggested that long-term ecological monitoring of benthic macroinvertebrate fauna is needed for sustainable management of Daecheon stream.

• Journal of the Korean Institute of Landscape Architecture
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• v.18 no.4
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• pp.7-16
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• 1991

This research investigated soil, plants, insects and birds in the Mongchon Earth Fort, establishing the 11 plots, according to planting treatment, in order to present management method for ecological stability of species in the ground covering plots. The results of analysizing the investigated data summarize as follows. 1. In the ground covering plots without upper layer, the density and coverage of middle and low layer in the natural plots were higher than those in the artificial plots. 2. In the ground covering plots without upper layer, the density and coverage of low layer were higher than those in the artificial, while the density and coverage of herb layer in the natural plots were lower. 3. Whether there was upper layer or not, the total species diversity and enenness of the ground covering community in the natural plot without artificial treatment and natural treatment plot were higher than those ground covering. 4. In the ground covering plots with upper layer, the species diversity of ground covering in the plots without artificial treatment is high, while the species diversity in the plots with natural treatment caused the secondary succession is higher than that of the natural plot. 5. In the ground covering plots without upper layer, the species diversity in the plots with artificial management was higher than that of natural plots, while the evenness in the plots with artificial management was lower. 6. In the ground covering plots with upper layer the species diversity of insect in the plot of natural state was higher than that of insect in the plots with artifical treatment. 7. Synthetically, in the area with upper layer the species diversity of the ground covering community in the natural plot was high, while in the area without upper layer, the species diversity of it in the plots with artificial treatment was high. The insect turned up frequently in the plots of high species diversity of the ground covering, so the bird did in the plots of high species diversity of the ground covering and insects.

• Mycobiology
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• v.42 no.4
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• pp.331-338
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• 2014

To examine the effects of water stress and Cenangium ferruginosum (CF) on the fungal endophytic community of needles of Pinus koraiensis (PK), fungal endophytes isolated from the needles of 5-year-old PK seedlings were compared before and after exposure to water stress conditions and artificial inoculation with CF ascospores. Artificial CF inoculation was successfully confirmed using PCR with CF-specific primers (CfF and CfR). For comparison of the degree of water deficit in water-stressed and control groups of PK seedlings infected with CF, the water saturation deficit and water potential were measured. Lower water potential estimates were found in the water-stressed seedlings than in the control group. The fungal endophytes isolated from the second-year needles of non-water-stressed seedlings before and after CF inoculation revealed that primary saprobes were approximately 30% and 71.7%, respectively, and the remaining endophytes were rot fungi or pathogens. Sixty days after CF inoculation, diverse fungal endophytes in the first-year needles were isolated from the water-stressed seedlings. However, some fungal endophytes isolated from the non-water-stressed seedlings were also identified. Fungal endophytes in the second-year needles of the water-stressed and non-water-stressed seedlings were approximately 8% and 71.7% of saprobes, respectively, and the remaining endophytes were rot fungi or pathogens. On the basis of the results, we conclude that water deficit and CF can have an effect on fungal endophytic communities in the needles of PK seedlings.

• Journal of Ecology and Environment
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• v.29 no.4
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• pp.323-330
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• 2006

We investigated the impact of watermelon grafted onto Cucumber Green Mottle Mosaic Virus (CGMMV)-resistant transgenic watermelon rootstock on insects as non-target organisms in a greenhouse in 2005. We quantitatively collected insect assemblages living on leaves and flowers, and we used sticky traps to collect alate insects. We compared the patterns of insect assemblages and community composition, cotton aphid (Aphis gossypii Glover) on watermelon leaves and western flower thrip (Frankliniella occidentalis Trybom) on watermelon male flowers, between CGMMV-resistant transgenic watermelon (TR) and non-transgenic watermelon (nTR). Non-parametric multidimensional scaling (NMS) ordination verified that insect assemblages on leaves and sticky traps were different between TR and nTR (P<0.05). The insect assemblages on male flowers were not statistically significant. Multi-response permutation procedures proofed our results from NMS results (P>0.05). Conclusively, TR watermelons appear to have some adverse effects on the population of cotton aphids on leaves and sticky traps, but watermelon male flowers do not show an adverse effect. Further research is required to assess the effect of TR on the aphid and western flower thrip. Life table experiments might support the specific reason for the adverse effects from leaf assemblages. Assessment of non-target impacts is an essential part of the risk assessment of non-target insects for the impact of transgenic organisms.

• Ecology and Resilient Infrastructure
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• v.4 no.1
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• pp.44-53
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• 2017

In order to investigate the response in fauna and biological communities of terrestrial insects to the vegetation encroachment on the sandbar, species composition, species diversity, functional species traits and community structure of land-dwelling insects sampled by a pit-fall trap were compared at the bare and vegetated sandbar of a typical sand-bed stream, the Naeseong Stream, Korea. Species diversity of the insects was increased but their density was decreased as the riparian vegetation encroached at the sandbar. In particular, indicator species of bare sandbar such as Cicindela laetescripta and Dianemobius csikii, were found at the bar sandbar. The insect communities were clearly classified at the bare and vegetated sandbar according to coverages of riparian plants. The food web of the bare sandbar was composed of detritus - detritivore and scavenger - predator consisted mainly of Coleoptera. On the other hand, the food web of the vegetated sandbar was composed of plants - sucking and chewing herbivore - parasitoid and predator. These results showed that biodiversity of terrestrial insects was increased, food web was changed from grazing to detritus food chain, and insect fauna specific bare sandbar disappeared as the riparian vegetation invaded on the sandbar of a sand-bed stream.

• Korean Journal of Ecology and Environment
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• v.55 no.4
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• pp.305-319
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• 2022

The community temperature index (CTI) reflects the temperature and environmental preferences of the community. We investigated the distribution patterns of major aquatic insect assemblages (Ephemeroptera, Plecoptera, and Trichoptera; EPT) based on CTI in streams of South Korea. We selected unpolluted 151 study sites at upper streams(less than 3^rd) with less than 1.5 mg L^-1 of biochemical oxygen demand. Study sites were clustered into six groups based on the similarities of their EPT composition. All three orders showed a continuous decrease in the number of species as CTI increased, especially in Plecoptera. In addition, the functional feeding groups were also significantly changed according the CTI changes. Temperature tolerance range of each group's indicator species varied according to the CTI of the group. Finally, changes of CTI reflected differences of EPT assemblages according to the differences of environmental condition including temperature. Therefore, CTI can be applied to the evaluation and preservation of stream ecosystems and prediction of community changes due to climate change.

• Korean Journal of Environmental Biology
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• v.33 no.3
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• pp.330-337
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• 2015

Pre-monsoon dynamics of zooplankton community were investigated in Yongwol West River tributary; wetland shaped Korean Peninsula. Zooplankters were collected at three sites (stn 1: Yongwol West River, stn 2: Pyungchang River, stn 3: Jucheon River) monthly during the period between March and July 2014 except April. Totally 58 taxa of zooplankton occurred, consisting of 27 species of rotifer, 18 species of cladoceran, eight species of copepod, four kinds of aquatic insect larvae and one nematod. Lotic cladocerans of Alona spp. belonging to Chydoridae occurred frequently while typical lentic ones of Bosmina spp. and Daphnia spp. were not distributed, then sampling sites may be located in lotic waters. Zooplankton abundance recorded as $4,451-8,011indiv{\cdot}m^{-3}$ in Jucheon River but never exceeded $500indiv{\cdot}m^{-3}$ in other rivers. In Yongwol West River, dominant taxa were aquatic insect larvae from March through June and succeeded to cladocerans and copepods in July. Similar succession was observed in Jucheon River where aquatic insect larvae dominated in March and changed to cladocerans and copepods from May with high abundance. No such succession of zooplankton community was detected in Pyunchang River. Species diversity indices were the highest in Yongwol West River except in March. High values of dissolved oxygen ($9.0-11.0 mg{\cdot}liter^{-1}$) may show the characteristics of mountain streams. Water temperature increased gradually from $10.1^{\circ}C$ to $27.9^{\circ}C$ and pH varied within generally high range between 7.9-8.9, respectively. High value of pH seems to be derived from lime stone mines and cement factories around the studied area.

• Korean Journal of Environmental Biology
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• v.35 no.4
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• pp.476-491
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• 2017

The water spider (Argyroneta aquatica), a rare member of its species, is one of the few insects known to live under water all over the world. In Korea, the water spider can be found only in the Eundae-ri, Yeoncheon, Gyeonggi province, where they are designated as a natural monument. However, loss of habitat is obvious, as the Eundae-ri wetland undergoes hydrarch succession. Loss of habitat has a direct impact on the water spider population. Thus protective measures for the water spider are needed to preserve the water spider habitat. In this study, a sweeping and visual survey of insect species was conducted in the water spider habitat from May to September 2015. The characteristics of each one of the different insect species and the community features were analyzed in this study. A total of 3,929 insects representing 276 species from 13 orders collected for the analysis. The most frequently collected insects from the Order Hemiptera represented 24.2% of total species and 82.3% of the total number of insects. Community analyses showed dominance, diversity, evenness, and richness indices of 0.23, 2.27, 0.41, and 31.2, respectively. Compared with the previous survey data, these results showed that reduction of the spider's wetland habitat caused the most commonly collected insects to adapt and spread to the surrounding terrestrial environment.