• Journal of agriculture & life science
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• v.44 no.6
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• pp.45-50
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• 2010

Soil characteristics by site types (slope, topography and stand) were analyzed to provide the basic information for sustainable management of Nari basin in Ulleung Island. The content of total N of Nari basin was lowest at the north slope, this site had also significantly low soil pH and content of available P. The result of soil pH and content of total N analysis by topography, ranged from 5.13 of summit to 5.59 of plain and from 0.63% of plain to 0.87% of hill, respectively. Soil pH, content of total N and available P by stand were significantly different, which showed that stand types are more significant in explaining the soil properties. Available P content by slope, topography and stand ranged from 2.79 to 8.46 ppm, 3.99 to 8.46 ppm and 5.03 to 11.59 ppm, respectively. It was concluded that forest soil around Nari basin has relatively low available P content compared to other forest soil.

• The Journal of Engineering Geology
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• v.34 no.1
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• pp.13-24
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• 2024

The purpose of this study is to identify the geology, geologic structure, hydrogeology and geomorphic characteristics of the Nari Basin and establish the controls on the discharge of water 20,000~40,000 m³/day from the Choosan Yongchulso, Ulleung Island, South Korea. Pumice and lapilli tuffs showing well-developed stratification are the predominant rock types surrounding the spring. The spring shows a structure whereby discharge occurs along a lens-like erosion cave formed by differential erosion of strata comprising tuff or pumice tuff. The Choosan Yongchulso is located at the point where the planation surface of the Nari Basin' ends and steep slopes begin. The basin is bounded on all sides by these steep slopes, except in the north, where the Choosan Yongchulso is located. Given these geomorphic characteristics, the Choosan Yongchulso is regarded as the ultimate outlet of the basin catchment area.

• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.1
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• pp.23-35
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• 2010

For the sustainable conservation of forests within and around the somma of Nari basin in Ulleung Island, the stand structure and dynamics with the aspect, altitude and stand types were estimated by using analyses of importance value, plant species diversity, S$\o$rensen's similarity index and distributions of diameter classes. Results of the importance value analysis with vegetation stories on each stand showed that Fagus engleriana and Acer okamotoanum were dominant in most stands regardless of the aspect and altitude of the forest around the somma of Nari basin and the plant species composition among stands was not significantly different. The forest within Nari basin was composed of pine, beech, alder and deciduous-mixed stand. Moreover, the species composition was greatly different among the four stands. The diversity of plant species within stand was in general higher within Nari basin than around the somma, and among stands within Nari basin, the plant species diversity of pine and deciduous-mixed stand showed higher values than that of beech and alder stands. The similarity index among stands with aspect and altitude showed that the index among stands of eastern, western and northern slope in forest around the somma and forest within the basin ranged from 0.68 to 0.69, and the similarity among four stands with altitude was very high having index range from 0.85 to 0.95. The patterns of diameter class distribution of the major dominant species from four altitude classes followed an almost normal bell-shaped distribution. The results were interpreted as an indication that these forests will in general maintain a stable stand structure. Therefore, despite diverse topographic features around Nari basin, the stand structure and plant species composition among stands were not diversified as expected. For the conservation of diversity of forest plant species and of forest ecosystems, a promising and intensive program should be considered.

• Journal of agriculture & life science
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• v.45 no.3
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• pp.1-7
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• 2011

This study was carried out to provide the basic information for effective preservation and management of forest community of Nari basin in Ulleung Island. Forest community in Nari basin was classified into Fagus engleriana community, Sorbus amurensis community, Pinus densiflora community, Celtis jessoensis community and Alnus maximowiczii community. As the result of DCCA ordination analysis, sea level among environmental factors had high correlation with community distribution. Fagus engleriana community and Sorbus amurensis community correlated highly with aspect, Na content, and C/N ratio. There was a high correlation between Celtis jessoensis community and the content of Ca and K. Alnus maximowiczii community was distributed in site where CEC content is high. Pinus densiflora community was distributed in site where the content of Ca and CEC is high.

• Korean Journal of Environmental Biology
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• v.36 no.1
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• pp.21-32
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• 2018

This study was carried out to define the characteristics of the identified ground-dwelling invertebrate communities at Nari basin and Tonggumi area in Ulleungdo Island, designated as a nationally important agricultural heritage. The habitat types were divided into the following categories: crop land, forest, and ecotone, and the soil-dwelling invertebrates were collected according to habitat type. The ground-dwelling invertebrates were collected using a pitfall trap, and a self-organizing map (SOM) was applied to the invertebrates dataset to define the characteristics in invertebrates distribution. The SOM clearly classified the relevant information into four clusters, and extracted ecological information from the invertebrates dataset. The cluster II was composed of invertebrate communities which are collected in the Tonggumi area. The Tonggumi area is where mountainous areas were developed for agricultural purposes, which has geographical features commonly observed in Ulleungdo Island. It is noted that the cluster II has different characteristics as compared other clusters. The results of this study are expected to be used for the preservation of agricultural environment and maintenance of biodiversity by providing basic data, on the biotope of Ulleungdo Island designated as a nationally important agricultural heritage and information on the characteristics of the applicable ground-dwelling invertebrate communities.

• The Journal of Engineering Geology
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• v.29 no.3
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• pp.223-236
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• 2019

Resistivity surveys can identify the distribution of geological units and structures (including fragmented fault zones), the extent of weathered and modified geological strata, and the characteristics of groundwater. This study aims to analyze the underground sedimentary layers and geological structures near the Nari and Albong Basins of Ulleung-do, Korea, focusing on six survey lines to identify the spatial trends in subsurface resistivity. A modified dipole array method (D method) was employed, combining resistivity results obtained by existing dipole array methods (A and C methods). The modified method provides optimal analysis of the cross-section of underground resistivity, and shows a clear boundary between a low-resistivity zone (${\leq}500{\Omega}{\cdot}m$) of sedimentary layers and weak zones, and a high-resistivity zone (${\geq}5,000{\Omega}{\cdot}m$) of volcanic rock (trachyandesite). The estimated average thickness of the sedimentary layers is 50~100 m for the Albong Basin and 100~200 m for the Nari Basin. An anomaly zone, different from the weak zone in the bedrock, is identified as a caldera fault, and the low-resistivity zone extends from the surface down to the lowest survey depths.

• The Journal of Engineering Geology
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• v.18 no.3
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• pp.321-330
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• 2008

This study, geological survey was carried out in order to study on the geology, geological structure and volcanic activity of the Ulleung-do volcano body. Ulleung-do is the volcano body of about 3,000m heights from the East Sea seabed. The geology of Ulleung-do is divided into basaltic agglomerate, trachytic agglomerate, trachyte, trachytic pumice and trachyandesite in ascending orders. The faults in caldera of Nari Basin came to make the reverse triangle style in compliance with sinking. The faults in circumference of Nari Basin are ranging with northeast-southwest direction and northwest-southeast direction. The Quaternary volcanic activities in the Ulleung-do are divided into 5 activity period. The engineering geologists and the applied geologists were not easy to apply because complicated geology of Ulleung-do. Therefore, this study supplied simple geology of Ulleung-do for them.

• Korean Journal of Plant Taxonomy
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• v.47 no.1
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• pp.46-50
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• 2017

The genus Lilium comprises about 100 species and is a major element of the family Liliaceae in temperate region of North Hemisphere. In the light of recent studies on the genus, we tried to examine the taxonomy of three Korean species (L. hansonii, L. tsingtauense, and L. distichum) belonging to section Martagon. The four available chloroplast regions (rbcL, matK, ndhF, and atpB) in Lilium species were selected and analyzed for a maximum likelihood phylogeny. As a results, three Korean species of section Martagon formed a monophyletic group. However, they nested within paraphyletic section Sinomartagon. Further, the discussions on taxonomic affinities of Korean species have made based on comparison between topology of phylogenetic tree and morphology.

• The Korean Journal of Mycology
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• v.43 no.1
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• pp.53-57
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• 2015

Ulleungdo is a volcanic island inhabited by a variety of animals and plants in an oceanic climate in the East Sea. The presence of filamentous fungi has been rarely reported in Ulleungdo. Thus, in this study some plants in the Nari basin and soils in the Dodong region were sampled. Fungi were isolated from the soil and identified by microscopical and molecular biological methods. Coniothyrium aleuritis, Hypocrea valdunensis, Pestalotiopsis uvicola and P. caudate were identified and found to be undescribed species in Korea.

• Korean Journal of Plant Taxonomy
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• v.36 no.2
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• pp.129-136
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• 2006

Thymus quinquecostatus var. magnus (Nakai) Kitam., an endemic taxon in Ulleung Island, is lectotypified. The lectotype is designated based on careful examination of the original materials (deposited in TI) cited in the protologue of the variety. In addition, taxonomic identity of T. quinquecostatus var. japonicus H. Hara, a problematic name often mistakenly referred to the above taxon, was throughly reexamined.