• Journal of Environmental Science International
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• v.19 no.8
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• pp.1035-1046
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• 2010

The purpose of this study is to investigate distribution of the vegetation and insects of coastal dunes in the Yangyang area. The field survey was carried out Osan and Dongho coastal dunes during the period from June to July 2008. A total of 68 taxa were identified including 30 families, 60 genera, 59 species, and 9 varieties. 1 species(Glehnia littoralis) was recorded as designated rare plant of Korea Forest Service. The naturalized plants were 8 families, 13 species. The urbanization rate of naturalization index was 4.8% and 19.1% respectively. The land insect appeared with the 10 order, 23 families including 10 Korean specific species and 16 environmental indicator species for coastal dune. The species in Order Coleoptera was most, followed by Hemiptera, Orthoptera and Odonata respectively.

• Korean Journal of Environmental Biology
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• v.26 no.3
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• pp.226-232
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• 2008

Sampling of the ground beetles in four 'gotjawal' terrains of Jeju island was conducted from April to October, 2007, using pit-fall trap. Totally 2,887 individuals of 23 species belonged to 4 families were collected. The species diversity index was the highest at Aeweol gotjawal (AW), while it was the lowest in Hangyeong-Andeog gotjawal (HA). Clustering analysis revealed that the insect communities of four gotzawals were grouped in only one cluster. Jocheon-Hamdeog gotjawal (JH) formed a cluster with Gujwa-Sungsan gotjawal (GS) at the lowest chord distance (0.24). At the higher chord distance of 0.50, AW fused the cluster of JH and GS. HA fused with the rest three terrains, forming a single cluster at the highest chord distance of 0.98.

• International Journal of Industrial Entomology and Biomaterials
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• v.43 no.1
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• pp.22-28
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• 2021

Natural nonwoven silk fabric has attracted researchers' attention owing to its unique properties as a biomaterial. It is fabricated by reeling, wetting, and hot pressing natural silk filament from silkworm cocoons. In this study, silkworm cocoons were immersed in water at different temperatures for various durations to examine the effects of wet treatment on their crystallinity and morphology. As the treatment temperature and time increased, the cocoon's silk filament separation became more evident, and fibroin strands were observed in it. The crystallinity indexes of the silkworm cocoons increased until a treatment time of 2 h and remained constant thereafter. The increase in the crystallinity index using wet treatment was enhanced by increasing the treatment temperature. Although the weight loss of the silkworm cocoon was insignificant until 40℃, it was appreciable above this temperature, and the degree of weight loss constantly increased with increases in the treatment temperature and time.

• Mycobiology
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• v.46 no.2
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• pp.85-91
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• 2018

Endophytic fungi strains (n = 81) were isolated from the leaves, barks, and fruits of Camellia oleifera from Hunan province (China) to delineate their species composition and potential as biological control agents of C. oleifera anthracnose. The fungi were identified by morphological and phylogenetic analyses. Fungal colonization rates of the leaves, barks, and fruits were 58.02, 27.16, and 14.81%, respectively. The isolates were identified as 14 genera, belonging to two subdivisions, Deuteromycotina and Ascomycotina; 87.65% of all isolates belonged to Deuteromycotina. The dominant species, occurring with a high relative frequency, were Pestalotiopsis sp. (14.81%), Penicillium sp. (14.81%), and Fusarium sp. (12.35%). The Simpson's and Shannon's diversity indices revealed the highest species diversity in the leaves, followed by the barks and fruits. The similarity index for the leaves versus barks comparison was the highest, indicating that the number of endophytic fungal species shared by the leaves and barks was higher than barks and fruits or leaves and fruits. Based on the results of dual culture experiments, only five strains exhibited antifungal activity against C. oleifera anthracnose pathogen, with isolate ty-64 (Oidium sp.) generating the broadest inhibition zones. Our results indicate that the endophytes associated with C. oleifera could be employed as natural agents controlling C. oleifera anthracnose.

• Korean journal of applied entomology
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• v.59 no.2
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• pp.83-91
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• 2020

We assessed efficacy of spraying pesticides from an unmanned helicopter to control two insect species, Monochamus alternatus and M. saltuarius, which are vectors of pine wood nematodes. Control efficacy of thiacloprid FL (33×), acetamiprid ME (33×), and flupyradifurone SL (33×) was determined by placing caged insects in the canopy of pine trees (Pinus sp). Water-sensitive paper was used to record the spray pattern of pesticide droplets and the degree of coverage; furthermore, we investigated peripheral scattering due to spraying. The three pesticides showed > 96% control efficacy against the targeted vectors, and pesticide droplet spray patterns were similar. Peripheral scattering was observed up to 20 m in front and 10 m to the left, right, and behind the targeted area. The coverage index of all the directions at 5 and 10 m distance was 6-7 and 2, respectively.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.23 no.6
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• pp.167-185
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• 2020

The purpose of this study is to prepare a plan for improving the bird habitat environment of Linear Park. To this end, after grasping the status of bird habitats on the Gyeongchun Line Forest Road, a representative linear park in Seoul, the habitat environment was evaluated and the correlation with the bird habitat was analyzed to derive a plan to improve the habitat environment. The results for correlation between diversity of birds and habitat environment were as follows. For the habitat environment inside the park, the order of positive correlation was in the order of park area (0.92), number of insect species (0.87), green area ratio (0.77), average width of linear park (0.74), Biotope area ratio (0.73), Immigration planted species (0.57). Also, for habitat environment outside the park, the bird diversity was influenced in the order of area outside the park (0.88), green area ratio of the park (0.76). Thus, in order to enhance the diversity of birds found in the park, the bird habitat environment inside the park needs to expand the park area, secure insect diversity, enhance green area ratio and ecological area ratio, expand the width of linear park, and lower the impermeable layer. For the bird habitat environment outside the park, wider area, green area ratio, and forest area of the park influenced on better bird habitation while lower ratio of road space and building-to-land ratio influenced on higher bird diversity. It is necessary to create an environment inhabitable for various species of birds and to make a healthy and pleasant city urban system for co-existence of human and living creatures.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.4
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• pp.54-61
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• 2017

Strengthening the protection and management of very old trees is an important aspect of urban site preservation, urban design and construction. Rating various danger factors to evaluate the degree of danger posed can help to create the correct protective countermeasures. In order to develop the danger evaluation index, this study performed four round surveys by using the Delphi method and collected opinions from experts in related fields. Necessary indexes were fully added in the first and second round while the indexes falling beyond the guidelines were deleted. From the final analysis results, five areas derived a total of forty-one indicators to create a degree of danger index from vigour status, growth and development status, diseases and insect pests, soil status, and management status. The degree of danger evaluation index can provide basic data for the protection of very old trees.

• Journal of Ecology and Environment
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• v.46 no.4
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• pp.324-333
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• 2022

Background: The Korean scarlet dwarf, Nannophya koreana Bae (Odonata: Libellulidae), is anendangered dragonfly with an increasing risk of extinction owing to rapid climate changes and human activities. To prevent extinction, the N. koreana population and their habitat should be protected. Therefore, suitable habitat evaluation is important to build the N. koreana restoration project. The habitat suitability index model (HSI) has been widely used for habitat evaluation in diverse organisms. Results: To build a suitable HSI model for N. koreana, 16 factors were examined by seven experienced researchers. A field survey for N. koreana observed sites and spatial analysis were conducted to improve the model. Five factors were finally selected by this procedure (crown density, open water surface, water depth, pioneer plant cover, and type of water source). Finally, the N. koreana HSI model was generated with the five adjusted factors based on interview, field survey, and spatial analysis. This model was validated by a current N. koreana habitat in 2021. With this model, 46 sites in Uljin-gun, Korea, were surveyed for N. koreana habitats; five sites were identified as core habitats and seven as potential core habitats. Conclusions: This model will serve as a strong foundation for the N. koreana restoration project and as a reference for future studies on N. koreana and other endangered insect populations. Further analysis and long-term data will improve the efficacy of this model and restore endangered wildlife.

• Korean Journal of Microbiology
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• v.51 no.3
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• pp.209-220
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• 2015

In this study, gut bacterial communities in xylophagous insects were analyzed using the pyrosequencing of 16S rRNA genes for their potential biotechnological applications in lignocelluloses degradation. The result showed that operational taxonomic units (OTUs), species richness and diversity index were higher in the hindgut than in the midgut of all insect samples analyzed. The dominant phyla or classes were Firmicutes (54.0%), Bacteroidetes (14.5%), ${\gamma}-Proteobacteria$ (12.3%) in all xylophagous insects except for Rhinotermitidae. The principal coordinates analysis (PCoA) showed that the bacterial community structure mostly clustered according to phylogeny of hosts rather than their habitats. In our study, the two carboxymethyl cellulose (CMC)-degrading isolates which showed the highest enzyme activity were most closely related to Bacillus toyonensis $BCT-7112^T$ and Lactococcus lactis subsp. hordniae $NCDO\;2181^T$, respectively. Cellulolytic enzyme activity analysis showed that ${\beta}-1,4-glucosidase$, ${\beta}-1,4-endoglucanase$ and ${\beta}-1,4-xylanase$ were higher in the hindgut of Cerambycidae. The results demonstrate that xylophagous insect guts harbor diverse gut bacteria, including valuable cellulolytic bacteria, which could be used for various biotechnological applications.

• Korean journal of applied entomology
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• v.60 no.1
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• pp.123-133
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• 2021

In order to use Osmia cornifrons more effectively in apples, we investigated the pollination effect and nesting activity of O. cornifrons on 'Hongro', the middle-season cultivar, and 'Fuji', the late-season cultivar. There was a significant difference in the nesting activity and pollination effect of O. cornifrons depending on the apple cultivar. The nesting activity, rate of trap nesting, and reproduction in 'Fuji' were 2.5, 1.5, and 3.8 times greater than in 'Hongro', respectively. The pollination effect according to cultivar 'Fuji' was 1.6 times greater than that of 'Hongro' in the central fruit set. In terms of the quality of fruit, the asymmetry index of 'Fuji' was 2.5 times lower than that of 'Hongro', and the number of apple seeds of 'Fuji' was 1.9 times greater than that of 'Hongro'. The main reason for this result was the air temperature. The activity of O. cornifrons was most affected by air temperature (R2 = 0.578). It is expected that the nesting activity and pollination effect are great in 'Fuji' (17.4-24.1℃) when the temperature during the blooming period is higher than that of 'Hongro' (12.5-20.2℃). Our study provides important information on stable apple production for apple cultivators, and can be used as an evidence for changes in flora and insect fauna caused by climate change.