• Journal of the Korean Magnetics Society
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• v.26 no.6
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• pp.213-218
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• 2016

This study reviewed mineral composition on Scoria samples of this area, atomic value state of oxidized steel, and magnetic property in order to look into characteristics of scoria that was distributed in southern area of mountainous areas, Halla Mt. of Jeju Island. By XRD analysis, mineral composition was confirmed, and characteristics of iron compounds existed in samples were investigated through $M{\ddot{o}}ssbauer$ spectroscope. Composing minerals could be learnt as feldspar basalt from XRD analysis because composting minerals were composed of quartz and feldspar anorite mainly, and iron compounds were made up with olivine, pyroxene, ilmenite, hematite, and magnetite. By $M{\ddot{o}}ssbauer$ spectroscope analysis on these iron compounds. it consisted of hematite and magnetite which showed hyperfine magnetic field of sextet mostly, and also doublet by olivine, pyroxene, ilmenite could be seen as appearing together. As a result of comparing with samples of Jeju western area having been announced in previous research, I.S. and Q.S. values of olivine, $Fe^{2+}$, were 122 mm/s and 3.09~3.13 mm/s respectively, and a fact could be known that $Fe^{2+}$ olivine having similar structure each other was contained, and the ratio of $Fe^{3+}/Fe_{tot.}$. was 85.90~92.82 %. From these findings, it was able to be presumed that they belonged to samples having been formed on the land at the same period of time. As a result of investigating area ratio of tetrahedron (A site) and octahedron (B site) regarding magnetite in samples, it was turn out to be 0.22~0.55 less than 2.

• Korean Journal of Environment and Ecology
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• v.21 no.3
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• pp.278-289
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• 2007

This study investigated species formation and their vegetation on the roadsides of 1100 Road and 5 16 Road in Hallasan National Park from August 2004 to December 2006 to provide basic data for distributional attribute of the naturalized plants. The vascular plants investigated on the roadsides of Hallasan National Park were found to be 62 families, 145 genera, 197 taxa in total, in which naturalized plants were recorded as 11 families, 29 genera, and 37 taxa. The floristic formation at 1100 Roadside was composed of Festuca arundinacea-Dactylis glomerata association, which was again divided into Trifolium pratense-Plantago lanceolata sub-association and Sasa quelpaertensis-Gleichenia japonica sub-association. The florisitic composition of the 5 16 Roadside was sorted as Festuca arundinacea-Dactylis glomerata association, Oplismenus undulatifolius-Potentilla fragarisiiforlia, elatior association, Ambrosia artemisiifolia, and etatior-Persicaria thunbergii association. Among the naturalized plants distributed at this area, the annual plant accounts for 51.4%[19 taxa] and the plant of European origin accounts for 70.3%[26 taxa]. As for the background of the introduction of these plants, the case of introduction for forage or a mixture with grain and for pasture was 35.1% and 21.6% respectively, showing higher introduction circumstances than others. As shown in the study, most of the roadsides were occupied by the naturalized plants- Festuca arundinacea and Dactylis glomerata association and various naturalized plants; thus we can assume that it's because Festuca arundinacea and Dactylis glomerata association were mostly used for re-vegetation of the destroyed areas due to road construction or expansion or road maintenance and improvement project.

• Korean Journal of Environment and Ecology
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• v.25 no.5
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• pp.658-665
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• 2011

An wild boar species which has been known as an extinct species on Jeju Island, was recently observed in the surrounding areas of Mount Halla. Based on the molecular techniques, this study examines whether they are crossbred with domesticated pig breeds. Intraspecific genetic relationships with other wild boar populations and molecular sexing were examined as well. Total of four molecular markers on mitochondrial DNA(control region and ND2) and nuclear DNA(MC1R and KIT) were applied to test crossbreeding between with domesticated pig breeds, such as Landrace, Large White, Berkshire, Hampshire, and Duroc. All individuals of wild boar population had identical mtDNA control region(CR) sequences. In addition, the sequences were the same as those of some native pig breeds which are distributed in Northeast China, but different from those previously reported from the Korean Peninsula up to date. These results suggest that this population may have originated from a genetic lineage had been not previously studied and genetically related to Chinese native pig breeds. Molecular sexing results show that there are twice as many females as male. Thus the population is under expansion and its size will dynamically increase if not controlled.

• Analytical Science and Technology
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• v.24 no.1
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• pp.24-37
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• 2011

The ionic compositions of atmospheric aerosols were investigated and characterized in coastal and mountainous sites of Jeju Island, which were Gosan and Mt. Halla-1100 sites respectively. It was found that the concentrations of nss-$SO_4^{2-}$ (non-sea salt sulfate) and $NH_4^+$ at two measurement sites were almost similar and they showed high concentrations in June at the same time. The concentration of soil-originated nss-$Ca^{2+}$ (non-sea salt calcium) was generally associated with that of anthropogenic $NO_3^-$ and its concentration was increased during spring season. From the comparison of time-series variation and regression analysis of ionic species between two measurement sites, TSP (total suspended particulate) in Gosan site was directly influenced by sea salt particles and the concentration levels of nss-$SO_4^{2-}$, $NH_4^+$, nss-$Ca^{2+}$, $K^+$, and $NO_3^-$ were mainly related with long-range transported air pollutants rather than local pollution sources.

• Korean Journal of Plant Resources
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• v.34 no.5
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• pp.491-501
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• 2021

This study was carried out to investigate the occurrence of seedlings of Korean fir (Abies koreana) in Korean fir forest located on the eastern slope of Mt. Halla National Park. Between June and August in 2016, the systematic sampling method was applied to 125 plots of 5 m × 5 m quadrats and field survey was came out to measure the characteristics of sites and understory vegetation. Correlation analysis was applied to the variables quantified from the data collected. Total number of flora found at the study site is 31 in families, 44 in genera, and 56 in species. The main lower layer vegetation was investigated such as Jeju dwarf bamboo, Toothed club moss (Lycopodium serratum), Pacific fir moss (Lycopodium chinense), Climbing hydrangea (Hydrangea petiolaris) etc. Among these plant species, the vegetation which had a high positive correlation with the frequency and the coverage of seedlings of Korean fir were Jeju dwarf bamboo, Toothed club moss and Pacific fir moss.

• Journal of Ecology and Environment
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• v.44 no.4
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• pp.275-285
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• 2020

Background: In Korea, Symplocos prunifolia Siebold. & Zucc. is only found on Jeju Island. Conservation of the species is difficult because little is known about its distribution and natural habitat. The lack of research and survey data on the characteristics of native vegetation and distribution of this species means that there is insufficient information to guide the management and conservation of this species and related vegetation. Therefore, this study aims to identify the distribution and vegetation associated with S. prunifolia. Results: As a result of field investigations, it was confirmed that the native S. prunifolia communities were distributed in 4 areas located on the southern side of Mt. Halla and within the evergreen broad-leaved forest zones. Furthermore, these evergreen broad-leaved forest zones are themselves located in the warm temperate zone which are distributed along the valley sides at elevations between 318 and 461 m. S. prunifolia was only found on the south side of Mt. Halla, and mainly on south-facing slopes; however, small communities were found to be growing on northwest-facing slopes. It has been confirmed that S. prunifolia trees are rare but an important constituent species in the evergreen broad-leaved forest of Jeju. The mean importance percentage of S. prunifolia community was 48.84 for Castanopsis sieboldii, 17.79 for Quercus acuta, and 12.12 for Pinus thunbergii; S. prunifolia was the ninth most important species (2.6). Conclusions: S. prunifolia can be found growing along the natural streams of Jeju, where there is little anthropogenic influence and where the streams have caused soil disturbance through natural processes of erosion and deposition of sediments. Currently, the native area of S. prunifolia is about 3300 ㎡, which contains a confirmed population of 180 individual plants. As a result of these low population sizes, it places it in the category of an extremely endangered plant in Korea. In some native sites, the canopy of evergreen broad-leaved forest formed, but the frequency and coverage of species were not high. Negative factors that contributed to the low distribution of this species were factors such as lacking in shade tolerance, low fruiting rates, small native areas, and special habitats as well as requiring adequate stream disturbance. Presently, due to changes in climate, it is unclear whether this species will see an increase in its population and habitat area or whether it will remain as an endangered species within Korea. What is clear, however, is that the preservation of the present native habitats and population is extremely important if the population is to be maintained and expanded. It is also meaningful in terms of the stable conservation of biodiversity in Korea. Therefore, based on the results of this study, it is judged that a systematic evaluation for the preservation and conservation of the habitat and vegetation management method of S. prunifolia should be conducted.

• The Korean Journal of Ecology
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• v.24 no.6
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• pp.377-380
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• 2001

Herbivory is an important selective forces on plants by reducing the ability of the plant to compete with its neighbors and to produce offspring. Oak nut weevil(Mechoris ursulus Roelofs) females lay eggs in unmatured acorns and cut off the branch of oviposited acorns. To investigate the influences of branch-cutting behavior of oak nut weevils on oak production, we surveyed the horizontal and vertical distribution ranges of damaged oaks and depth of sites of overwintering larvae and quantified the amounts of biomass and acorn removed by the weevils on deciduous oak species. All of the endemic oak species in Korea were damaged by oak nut weevils in all of the study sites including Mt. Halla and Mt. Seorak. The upper limit of vertical distribution of damaged oaks by the weevils raried from 700 m to 900 m. Mostly their larvae were found in soil from 8.1 cm to 10.0 cm depth in winter. Percentage of annual net primary productivity($720g{\cdot}m^{-2}{\cdot}day^{-1}$) of oak species removed by the weevils was about 7%, which is higher than the percentage removed by all the herbivores in typical temperate forest(5%) and equivalent to that by all the herbivores in tropical forest. The predation percentage of annual acorn production by oak nut weevil was 27% in Q. mongolica and 33% in Q. acutissima. This results indicate that the branch-cutting behavior of oak nut weevil may be the most important factor regulating oak population and affecting other predators dependent on acorns.

• Korean Journal of Environmental Biology
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• v.37 no.3
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• pp.249-259
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• 2019

We investigated the tritrophic interactions associated with elevation and openness of dwarf bamboo (Sasa quelpaertensis Nakai) vegetation on Mt. Halla, Jeju Island. The interactions between dwarf bamboo plants and its consumers were investigated in four study sites with and without canopy along the elevation gradient. The ecological traits of dwarf bamboo included leaf area, water content, nitrogen content and carbon/nitrogen ratio. Arthropods were collected using a sweeping net and they were later divided into three different feeding guilds: herbivorous, omnivorous and predators. We found that the elevation and canopy openness on dwarf bamboo vegetation was positively related and as elevation increased and canopy opened, the bamboo densities and C/N ratio increased. However, the leaf area, water content and the N content decreased. The study sites with closed canopy indicated a relatively higher species richness of arthropods including insects. We concluded that the tritrophic interactions is closely related to the ecological characteristics of the dwarf bamboos, which is affected by elevation and canopy openness.

• The Journal of the Korea Contents Association
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• v.11 no.12
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• pp.442-454
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• 2011

The study seeks to explore essential factors that influence tourists' continual revisit intentions to storytelling. The variables some factors such as education value, emotional value, theme value, satisfaction, and revisit from the model to achieve the research objective. The survey was conducted by users who has previously experienced tourism storytelling. Structural equation modeling is used to investigate the relationships between the factors and results show that 'education value', 'emotional value', and 'theme value', a variables are positively related to tourists satisfaction and revisit intentions. In particular, two factors which are education and theme had strongly significant of tourist's attitude. The identified factors that influence revisit intentions on storytelling can be useful for analyzing the market trends and suggesting industrial guideline of Jeju Island and Mt. Halla.

• Journal of Plant Biology
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• v.34 no.4
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• pp.341-347
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• 1991

The character and differential species of Abies koreana community, a subalpine coniferous forest, on Mt. Hall a and its vegetation unit were reviewed, based on literature published up to date. Song and Nakanish (1985a) originally described Saso-Abietetum koreanae Song et Nakanishi 1985 for the community. At that time, we were fully justified in establishing the nomenclature. Nevertheless, against this nomenclature, Yim and Kim (1990) made a objection, and it was renamed as what is called Saso quelpaertensi-Abietetum koreanae (Song et Nakanishi) corr. Yim et Kim 1990. In their previous study(Yim et al., 1990) being the root of the nomenclature, however, they did not study on the full layers containing the moss layer of bryophyte and lichen for the stratification of the Abies koreana community, in spite of the importance of the species of moss layer for the selection of character and differential species of vegetation units belonging to Vaccinio-Piceetea Br.-Bl. 1939, and also the floristic composition from their study was not compared with that of the vegetation units of the subalpine coniferous forests in Korea Peninsula, Japan, Maritime Province of Siberia and Northeast China. Among the four character species selected by them, it is clear that Maianthemum bifolim and Lonicera maackii are species no having the characteristic value from the phytosociological viewpoint. Besides, Sasa quelpaerthensis described in their nomenclature is a synonym of S. palmata (Suzuki, 1978). Therefore, their nomenclature is invalid and comes under a contravention (Infringement of Priority) to the Code of Phytosociological Nomenclature (Barkman et al., 1986). Saso-Abietetum koreanae was amply justified also by author's recent study (Song, 1991)examined throughout the range of subalpine coniferous forest in Korea. With the discussion of justification of Saso-Abietetum koreanae, a association discussion was brought in the present review.