• The Journal of Engineering Geology
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• v.17 no.2 s.52
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• pp.235-251
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• 2007

Baeknokdam rock mass at the crest of Halla mountain is composed of Baeknokdam trachybasalt in the eastern region and Hallasan trachyte in the western region. On-going weathering, rockfall and collapse of Baeknokdam wall rock are closely linked to the weathering of trachyte distributed in the western region of Baeknokdam, though within the restricted area of eastern region trachybasalt blocks has been naturally formed and may be rolled down neering properties have been conducted. Based on the results of these experiments variations of mineralogical-petrographical characteristics of trachyte together with chemical and physical properties with respect to the degree of weathering have been analyzed. Weathering mechanism of Baeknokdam trachyte has been delineated by investigating the environmental cause of weathering and the peculiar features of weathered rock mass.

• Journal of Environmental Science International
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• v.19 no.4
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• pp.491-507
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• 2010

This study focuses on the fauna, seasonal prevalence and altitudinal distribution of the flies from March to November, 2008 in Mt. Hallasan, Jejudo Island, Korea. The fauna of flies was 39 species belonging to 5 Families which consist of 12 Calliphoridae, 19 Muscidae, 5 Sarcophagidae, 1 Dryomyzidae 1, Scathophagidae and 1 Anthomyiidae. The total number of flies collected was 21,605 with sex ratio of 57.98% in Mt. Halla. The ratio is higher than that of the residential area and other mountain survey sites. The average number of per trap individuals collected on the trapping day is 267, which is similar with the average of Mts. Jiryong, Juwang, Palgong and Gumo. The five dominant species showed a distinctive seasonal prevalence of 92.6% of the total flies: Chrysomyia pinguis (34.2%), Calliphora lata (25.3%), Hydrotaea dentipes(23.1%), Fannia scalaris (5.1%), and Lucilia caesar (4.9%). The seasonal prevalence of the flies was from the beginning of March to the end of November, and the highest peak time of the whole flies, males and females were different respectively. In the similarity index of the flies collected in different altitude, that of between 1,000 meters and 1,500 meters was the highest among the indices of 500 meters and above 1,000 meters. The index at each altitude was above 80% because of the same area. The diversity index of fly species was between 0.00 and 0.88 through altitudinal traps monthly. The highest index in Trap 1 was 0.88 in October, in Trap 2, 0.82 in July and in Trap 3, 0.63 in July. The diversity above 1,000 meters was most various in July. The five dominant species of C. pinguis, C. lata, H dentipes, F. scalaris, and L. caesar showed distinctive seasonal prevalence, relative abundance and altitudinal distribution respectively.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.12
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• pp.1873-1878
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• 2017

Both the introduction of the Renewable Energy Portfolio Standard (RPS) system into the electric energy market in 2012 and a decrease in the cost of constructing photovoltaic (PV) power plants have been increasing the number of MW PV plants in South Korea. Jeju Island is located at the center of three nations, South Korea, China and Japan, and its provincial government declared in 2012 that the island will be a clean region where greenhouse gases are not emitted by 2030. The Jeju provincial government is now doing its best to install PV plants and wind farms to realize a carbon-free island. In this study we investigated contribution of MW PV plants to the power of the electric grid during summer peak times on Jeju Island. Mt. Halla the highest mountain in South Korea, is located at the center of Jeju Island, and we divided the island into four regions and carried out analyses of a total of 24 PV plants. The average contribution of the PV plants in the respective region to electric power of Jeju Island during summer peak times was investigated and compared with those of the other regions. The best average contribution during the 12.5% maximum load period was obtained from the PV plants in the western region, and the value was 33% during 2015 and 2016.

• Journal of agriculture & life science
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• v.43 no.3
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• pp.1-6
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• 2009

This study has been carried out to measure the extent of damage for Witches' broom of cherry trees planted as street trees along the 5.16 road around the Halla Mountain. This study is expected to provide effective measures to prevent the infection of witches' broom. Among the cherry trees examined, almost all the trees of 40 years or over were severely infected. Those around 30 years old were infected as well, though they showing medium level of disease symptoms. However, cherry trees of less than 23 years were observed to be healthy without showing any symptoms. Cherry trees spontaneously growing within 30m width of the 5.16 road in the section from Sanchondan to Kyunwolak were less severely infected by Witches' broom (Taphrima waesneri), though there was a difference by tree age.

• Korean Journal of Microbiology
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• v.55 no.2
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• pp.171-173
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• 2019

The genus Cohnella, which belongs to the family Paenibacillaceae, inhabits a wide range of environmental niches. Here, we report the complete genome sequence of Cohnella sp. HS21, which was isolated from the rhizospheric soil of Korean fir (Abies koreana) on the top of Halla Mountain in the Republic of Korea. Strain HS21 features a 7,059,027 bp circular chromosome with 44.8% GC-content. Its genome contains 5,939 protein-coding genes, 78 transfer RNA (tRNA) genes, 27 ribosomal RNA (rRNA) genes, 4 noncoding RNA genes (ncRNA), and 90 pseudogenes. The bacterium contains antibiotic-related gene clusters and genes encoding plant cell wall-degrading enzymes.

• Journal of Climate Change Research
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• v.8 no.4
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• pp.401-414
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• 2017

Vegetation and landscape characteristics at the three highest summits of Republic of Korea, i.e. Seoraksan, Jirisan and Hallasan, are analyzed on the basis of species composition, physiognomy, vegetation distribution and structure of alpine plants, along with landform, geology, soil and habitat conditions. Dominant high mountain plants at three alpine and subalpine belts contain deciduous broadleaved shrub, Rhododendron mucronulatum var. ciliatum (31.6%), and evergreen coniferous small tree, Pinus pumila (26.3%) at Seoraksan, deciduous broadleaved tree, Betula ermanii (35.3%), evergreen coniferous tree, Picea jezoensis (23.5%) at Jirisan, and evergreen coniferous tree, Abies koreana (22.6%), deciduous broadleaved shrub, Rhododendron mucronulatum var. ciliatum, and Juniperus chinensis var. sargentii (19.4%) at Hallasan, respectively. Presence of diverse landscapes at the peak of Seoraksan, such as shrubland, grassland, dry land along with rocky areas, and open land may be the result of hostile local climate and geology. High proportion of grassland and wetland at the top of Jirisan may related to gneiss-based gentle topography and well developed soil deposits, which are beneficial to keep the moisture content high. Occurrence of grassland, shrubland, dry land, conifer vegetation, and rocky area at the summit of Hallasan may due to higher elevation, unique local climate, as well as volcanic origin geology and soil substrates. Presences of diverse boreal plant species with various physiognomy at alpine and subalpine belts, and wide range of landscapes, including rocky, grassland, shrubland, wetland, and conifer woodland, provide decisive clues to understand the natural history of Korea, and can be employed as an relevant environmental indicator of biodiversity and ecosystem stability.

• Food Science and Preservation
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• v.30 no.1
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• pp.15-27
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• 2023

Jeju Sasa borealis (S. borealis) is indigenous to the Halla Mountain area of Jeju Island, Republic of Korea. However, its dominance has retarded the development of other plant species and lowered biodiversity in this region. The aim of this study was to determine whether S. borealis silage (SS) supplementation affects the chemical composition and antioxidant activity in the fresh meat of Korean native goats (Capra hircus coreanae). The experiment was conducted on 12 Korean native goats at the finisher stage. The feeding groups were the Control (total mixed ration, TMR) and the Treatment (80% TMR + 20% SS). The animals were adapted for two weeks and then subjected to a six-month breeding experiment. Meat samples were excised from the neck, loin, rib, front leg, and hind leg of the slaughtered animals. The meat derived from the treatment group contained more taurine and anserine than that derived from the control group. Both groups did not significantly differ in terms of ω-6/ω-3 fatty acid ratio. The loin and front leg of the treatment group contained significantly higher vitamin E levels than those of the control group. DPPH, ABTS, and FRAP analyses disclosed that the loin and front leg had significantly higher antioxidant activity (p<0.05) than the other parts. Moreover, the loin and front leg cuts of the treatment group had higher antioxidant activity than those of the control group. The present study demonstrated that S. borealis supplementation could effectively improve Korean native goat meat quality.

• Korean Journal of Environmental Biology
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• v.29 no.3
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• pp.126-137
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• 2011

Although Sumunmulbangdui wetland at the Halla Mountain in Jeju Island, a kind of montane wetlands, has been considered to bear high biodiversity, no study has been reported on the bacterial diversity. In this study, soil and water samples were collected from the wetland in order to isolate novel bacterial species. Bacterial strains belonging to the phyla Bacteroidetes, Firmicutes, and Actinobacteria were isolated after spreading soil and water samples onto solid agar media. The 16S rRNA gene sequences of the strains assigned to the three phyla were compared to those of type strains of the species in the phyla. The strains that showed less than 98.7% 16S rRNA gene sequence similarity to the validly published species were considered to be novel species candidates. A total of 32 strains were regarded as novel species candidates in the phyla Bacteroidetes, Firmicutes, and Actinobacteria. Diversity of novel species candidates was very low; the candidates were confined to only few genera. In the Bacteroidetes, 13 novel candidate species were affiliated with the genera Mucilaginibacter, Sphingobacterium, Pedobacter, Flavobacterium, and Chryseobacterium. A total of 13 novel candidate species that assigned to the genera Paenibacillus Lysinibacillus, and Bacillus were identified in the phylum Firmicutes. Only two candidate species that belonged to the genera Mycobacterium and Nocardia were excavated in the Actinobacteria. Cultural, physiological, and chemotaxonomic characteristics have been determined for the novel species candidates, and the characteristics are described in this study.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.1
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• pp.1-28
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• 2019

This study analyzed the density and mortality rate of Korean fir at 9 sites where individuals of Korean firs were marked into the live and dead trees with coordinates on orthorectified aerial images by digital photogrammetric system. As a result of the analysis, Korean fir in each site showed considerable heterogeneity in density and mortality rate depending on the location within site. This make it possible to assume that death of Korean fir can occur by specific factors that vary depending on the location. Based on the analyzed densities and mortality rates of Korea fir, we investigated the correlation between topographic factors such as altitude, terrain slope, drainage network, solar radiation, aspect and the death of Korean fir. The density of Korean fir increases with altitude, and the mortality rate also increases. A negative correlation is found between the terrain slope and the mortality rate, and the mortality rate is higher in the gentle slope where the drainage network is less developed. In addition, it is recognized that depending on the aspect, the mortality rate varies greatly, and the mean solar radiation is higher in live Korean fir-dominant area than in dead Korean fir-dominant area. Overall, the mortality rate of Korean fir in Mt. Halla area is relatively higher in areas with relatively low terrain slope and low solar radiation. Considering the results of previous studies that the terrain slope has a strong negative correlation with soil moisture and the relationship between solar radiation and evaporation, these results lead us to infer that excess soil moisture is the cause of Korean fir mortality. These inferences are supported by a series of climate change phenomena such as precipitation increase, evaporation decrease, and reduced sunshine duration in the Korean peninsula including Jeju Island, increase in mortality rate along with increased precipitation according to the elevation of Mt. Halla and the vegetation change in the mountain. It is expected that the spatial patterns in the density and mortality rate of Korean fir, which are controlled by topography such as altitude, slope, aspect, solar radiation, drainage network, can be used as spatial variables in future numerical modeling studies on the death or decline of Korean fir. In addition, the method of forest distribution survey using the orthorectified aerial images can be widely used as a numerical monitoring technique in long - term vegetation change research.

• Korean Journal of Environmental Biology
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• v.29 no.3
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• pp.144-153
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• 2011

In this study, samples were collected from the Sumummulbangdui wetland at the Halla Mountain in Jeju Island in order to isolate novel bacterial strain. Bacterial strains belonging to the class Alphaproteobacteria, and Gammaproteobacteria were isolated after spreading samples onto solid agar media. The 16S rRNA gene sequences of the strains assigned to the two classes were compared to those of type strains of the species. The strains that showed less than 98.7% 16S rRNA gene sequence similarity to the validly published species were considered to be novel species candidates. A total of 19 strains were regarded as novel strains which can be regarded as novel species candidates. In the Alphaproteobacteria, 6 novel strains were affiliated with the genera Novosphingobium, and Rhizobium. A total of 13 novel strains belong to Gammaproteobacteria that assigned to the family Moraxellaceae, Pseudomonadaceae, and Enterobacteriaceae were identified. Cultural, physiological, chemotaxonomic characteristics and fatty acids compositions have been determined for the novel species candidates, and the characteristics are described in this study.