• Korean journal of applied entomology
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• v.53 no.4
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• pp.347-354
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• 2014

This study was carried out to clarify the change of butterfly community after clear cutting. Butterfly survey was conducted in clear cutting area, forest road, and forest using line transect method from May to November in 2011. A total of 32 species and 398 individuals of butterflies were observed. Abundance of food niche breadth and habitat type was significantly higher in clear cutting area than in forest. Estimated species richness and species diversity were significantly higher in clear cutting area than in forest. In clear cutting area, Leptidea amurensis and Argynnis niobe, vulnerable species, were abundant. This result suggests that grasslands formed by clear cutting play an important role to increase butterfly diversity in forest ecosystem.

• Journal of Ecology and Environment
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• v.34 no.4
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• pp.347-355
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• 2011

Effects of forest thinning on community level properties have not been understood yet in Korea. We investigated regeneration patterns and trajectories after a disturbance by applying a chronosequence approach. Light availability, litter and woody debris cover, and species composition were determined for twenty 50 m line-transect samples representing a disturbance duration gradient (within 11 years). Environmental factors such as light availability and coverage of woody debris and litter changed abruptly after thinning and then returned to the pre-disturbance state. Although species richness was gained at shrub and ground layer in a limited way in both forests, cover of various functional types revealed diversity in their responses. Notably, Alnus firma stands exhibited a larger increment of cover in woody plants. Ordination analysis revealed different regeneration trajectories between natural and planted stands. Based on ordination analysis, rehabilitated stands showed movement to alternative states compared with natural ones, reflecting lower resilience to perturbation (i.e., lower stability). Our results suggest that community resilience to artificial thinning depends on properties of the dominant species. But to get more explanatory ecological information, longer-term static observations are required.

• Fisheries and Aquatic Sciences
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• v.18 no.4
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• pp.411-416
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• 2015

We estimated abundance of the finless porpoise Neophocaena asiaeorientalis in the west coast of Korea in 2011 and compared it to the abundance data estimated by Park et al. (2007). The two researches used same line transect method operated by a vessel, and the study area were divided into the offshore and the inshore regions to assess variations in their abundance. In offshore regions population density of finless porpoises was $0.122ind./km^2$, which was lower than $0.565ind./km^2$ estimated in 2004. In inshore regions the population density was $0.151ind./km^2$, which was much lower than $0.638ind./km^2$ estimated in 2005. Thus, we estimate that the population densities of the finless porpoises in both the offshore and the inshore regions of the west coast of Korea has decreased by approximately 70% between 2004/2005 and 2011.

• Journal of Korean Society of Forest Science
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• v.105 no.2
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• pp.268-273
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• 2016

This study was conducted to clarify the differences in habitat structure and amphibian and reptile (herpetofauna) populations between before and after thinning in the coniferous and deciduous forests from June to September 2014 and 2015 at the Mt. Maewha of Hongcheon, Gangwon province, Korea. Forest structure was dramatically changed after thinning. Coverage of understory and mid-story were decreased while volume and number of downed trees were increased after thinning. We used line transect sampling method on a total of 4 transect lines, 2 lines in each forest type. 119 individuals of 5 amphibian species and 5 individuals of 3 reptile species were recorded. Mean number of amphibian species were decreased after thiining in the coniferous forest. There was no observed reptiles after thinning in the coniferous and deciduous forests. Detailed monitoring with different area, frequency and intensity might be needed to clarify more precise differences characterisitics of herpetofauna by thinning.

• Journal of the Korean earth science society
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• v.26 no.3
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• pp.253-267
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• 2005

Seasonal and spatial variations of tidal flat sediments were studied in Yeoja Bay. Results of the yearly observation of tidal flat transect lines indicated that the monthly change of grain size composition was not distinct from each tidal flat transect line, but it was quite clear that clay covered $40\~70\%$ of the sediment composition. Clay composed most highest in the northern part of the bay, and lowest in the western. As clay content increased, water and organic matter showed a tendency of increase, while the mean grain size was fixed per clay amount. Shear strength came out as 0 kPa as a whole. Seasonal variations of clay contents in each tidal flat were higher in winter and spring, but lower in summer and autumn. Thefine sediments were likely to be accumulated in the winter and spring. The average accumulation rate of each tidal flat was $-14.62\~38.57mm{\cdot}yr^{-1}$. The numbers showed $32.13mm{\cdot}yr^{-1}$ in the northern, $-14.62mm{\cdot}yr^{-1}$in the western, and $6.46mm{\cdot}yr^{-1}$ in the eastern part. During the coarse of this study sediment accumulation rates indicated that the sediments deposited continuously in the northern part of tidal flat, whereas erosion occurred in the western part. However, there was no distinct change in the eastern part. It was due to the clockwise lateral circulation in Yeoja Bay. Seasonally, sedimentation happened during the dry season (winter and spring) and erosion during the wet season (summer and autumn).

• Journal of Korean Society of Forest Science
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• v.103 no.1
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• pp.147-151
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• 2014

This study was conducted to clarify the characteristics of amphibian and reptile (herpetofauna) populations in a coniferous plantation and a deciduous forest from July to September 2013 in national forest, Hongcheon, Gangwon province, Korea. Coverage of understory, mid-story and overstory were more developed in a deciduous forest. We used line transect sampling method on a total of 4 transect lines, 2 lines in each forest type. Fifty two individuals of 4 amphibian species and 11 individuals of 3 reptile species were recorded. Mean observed number of herpetofauna species, individuals and species diversity index (H') were not significantly different between coniferous plantation and deciduous forest. This result related to ecological characteristics of herpetofauna. Habitats of herpetofauna were influenced on not only vertical structure of forests, but also climatic variables, thermoregulation and prey availability. The long-term monitoring and research on habitat preference and seasonal ecological traits of herpetofauna would be needed for conservation and management of herpetofauna in forest areas.

• Korean journal of applied entomology
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• v.50 no.2
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• pp.115-123
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• 2011

Although Guleopdo is small island of only $1.71\;km^2$, the endangered butterfly species, Argynnis nerippe, is abundant there. This study was carried out to estimate the abundance of A. nerippe in Guleopdo, using quadrate, mark-recapture, and line-transect methods. Although the study was insufficient, the population size was estimated at 4,467 to 6,700 larvae and approx. 1,000 adults. A. nerippe was the most abundant among butterfly species in Guleopdo, and it comprised 32% of the total butterflies. A total of 28 butterfly species were observed in this study, and 3 species of these species were migrating species. When the abundance of A. nerippe throughout the country during the period from 1938 to 2010 was studied, we found that it decreased abruptly in the 2000s. Presently, A. nerippe inhabits a few locations in the mid-northern region and western islands. The relatively high numbers of A. nerippe in Guleopdo was due to conservation of natural grasslands and grazing of livestock, which provides adequate habitat for this species.

• Korean Journal of Environment and Ecology
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• v.17 no.1
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• pp.1-8
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• 2003

This study was conducted to investigate the effects of road on bird community by line transect census method from May 2000 to January 2001 in Mt. Geumsan, Namhae-Gun, Kyeongsangnam-do. Canopy layer was more developed in forest area than road area. Understory vegetation of road area was more developed than forest area. Twenty six and twenty three bird species were observed in road and forest area, respectively, White's thrush and ashy minivet were observed just only in forest area, and Siberian blue robin, blue-and-white flycatcher and gold crest were in road area. The birds being to bush nesting and foraging guilds in road area were more than forest area. It is known that the road construction was negatively affected on bird community. However, road construction would be not so negative on bird community according to the results of thie study. It would be needed the maintenance of upper canopy layer and understory vegetation to reduce negative effect of road on bird communities in forest area.

• Korean Journal of Environment and Ecology
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• v.7 no.2
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• pp.213-220
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• 1994

This study was conducted to investigate bird community and to suggest a proper way how to manage and protect bird community in Tokyusan National Park. The survey was carried over 2 main trail districts by line transect method at 20, February and 22, July in 1993. The observed birds were belong to 5 orders 17 families 34 species, they also have Sparrow Hawk Accipiter nisus, Kestrel Falco tinunnculus(natural monument no. 323), White-backed Woodpecker Dendrocopos leucotos(R) and Japanese Waxwing Bombycilla japonica(R). It is estimated that grass region above 1,000m altitude provided breeding habitats for Gray-headed Bunting Emberiza fucata in summer and wintering habitats for Rosy Finch Leucosticte arctoa in winter, This shows that this region should be protected for inhabitation of these birds. Mujukucheontong valley of Tokyusan National Park, which had been a good habitat for valley-inhabituating birds before twenty years ago, has a lower species richness by increasing using density, and so this valley shoud be properly managed urgently.

• Korean Journal of Environmental Biology
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• v.38 no.4
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• pp.497-506
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• 2020

This study surveyed the altitudinal diversity and distribution of butterflies inhabiting Mt. Jirisan. Field surveys were conducted thrice (May, June, and July) using a line transect method along four routes in 2015. During the survey, a total of five families, 58 species, and 769 individuals were collected. Of the species collected, the majority belonged to the family Nymphalidae (28 species), followed by Hesperiidae (nine species), Pieridae (eight species), Lycaenidae (seven species), and Papilionidae (six species). As for the individuals, Pieridae accounted for the largest number (333 individuals), followed by Nymphalidae (309 individuals), Lycaenidae (63 individuals), Hesperiidae (33 individuals), and Papilionidae (31 individuals). A cluster analysis performed on the butterfly species distinguished three altitude zones. The butterflies showed different ecological traits in each of the altitude zones. Analysis of the altitudes of the habitats of eight dominant species revealed that each species inhabited a particular altitude. This study confirmed the hypothesis that continuous monitoring will identify changes in the altitudinal distribution and diversity of butterflies on Mt. Jirisan in response to climate change.