• Korean Journal of Plant Taxonomy
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• v.42 no.1
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• pp.98-107
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• 2012

This study was carried out to investigate the non-indigenous of Dokdo belong to Ulleung-gun, Gyeongangbuk-do, Korea, from 2008 to 2011. We divided the study into three steps depending on the recorded times of plants on Dokdo since 1973, when the ecosystem was disturbed by many plantation events. The results are as follows: 30 taxa (52.6%) until 1973, 24 taxa (42.1%) after 1973, and 3 taxa (5.3%) of cultivated plants depending on the 57 taxa of Dokdo. Management of the non-indigenous plants of Dokdo is necessary due to the great increase in interest by people, with many visitors to Dokdo.

• The Journal of the Acoustical Society of Korea
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• v.20 no.5
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• pp.92-99
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• 2001

To measure temporal variability of long- range transmission in northern part of the East Sea of Korea, low frequency acoustic sources were deployed on the continental shelf 0.4km south of Cape Shultz near the port of Vladivostok during October 1999. The transmissions of the phase modulated signals were recorded by VLA moored on the northern slope of Ulleung-do. The measured signals were processed for the acoustic arrivals and their variability in time. The temporal signal processing involves pulse compression of the phase-encoded signal, time spread and temporal coherence processing. Variability of the ocean sound speed field in time scales of short period seems to be dominated by random fluctuations caused by sound speed perturbation due to the vertical displacements associated with internal waves.

• 한국지구과학회:학술대회논문집
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• 2010.04a
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• pp.52-52
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• 2010

동해 한국대지 남부(south Korea Plateau)에서 2010년 2월에 한국해양연구원의 온누리호를 이용하여 해저지형 및 자생광물 탐사가 실시되었다. 다중빔 음향측심기를 이용한 해저지형 조사는 2-3 km 탐사측선 간격으로 약 400 L-km 정도가 실시되었다. 조사구역 A($37^{\circ}$ 16'-18'N, $130^{\circ}$ 02'-16'E)는 890-1,900 m의 수심범위와 남쪽으로 갈수록 수심이 깊어져 울릉분지(Ulleung Basin)와 연결된다. 크고 작은 소규모의 구릉이 사면을 따라 다수 분포하고 있다. 조사구역 B($37^{\circ}$ 26'-40'N, $130^{\circ}$ 23'-34'E)의 정상부는 900-1,000 m로 비교적 평평하게 나타났고, 남동방향으로는 2,200 m까지 급격하게 수심이 증가하는 사면으로 이루어져 있다. 한국대지내 노출 암반지역은 남동쪽 사면의 일부 지역에 분포하고 있다. 자생광물 탐사는 일차적으로 천부지층 탄성파탐사를 수행하여 시료채취 가능 여부를 현장에서 확인한 후에, A 및 B구역내 11개 지점에서 드렛지를 이용하여 암석시료를 채취하였다. 채취된 암석은 주로 현무암이며, 많은 양의 화산기원 부석(pumice) 및 화산재(box core 자료)도 확인되었다. 또한, 인광석으로 추정되는 암석과, 망간단괴(manganese nodules)와 망간각(manganese crust)의 일부 시료도 채취하는데 성과가 있었다.

• Journal of Species Research
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• v.11 no.2
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• pp.98-101
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• 2022

The genus Tripylina Brzeski, 1963 is a group of terrestrial nematodes that inhabit soil and semi-wet biomes, most of which have been reported from Europe, Asia, America, Africa, and New Zealand. Tripylina stramenti (Yeates, 1971) Tsalolikhin, 1983, belonging to the family Trischistomatidae Andrassy, 2007, is newly discovered from Korea. The specimens were collected from the edge of the valley of Ulleung-gun, Gyeongsangbuk-do, South Korea. Tripylina stramenti described herein shows typical morphological characters of the genus Tripylina, including six and four setae in a single whorl, present dorsal tooth and subventral teeth, prodelphic reproductive system of female, absence post-uterine sac, narrow sickle-shaped spicule of male and generally S-shaped tail. The specimens differ in their body width (from the New Zealand populations), outer labial setae length, cuticles thickness(from the West African populations), and nerve ring position (from Indian populations). This species is distinguished from other Tripylina species by its relatively large body, two anterior and subventral teeth, and single cervical seta. In this study, morphological characteristics and morphometric information of the Korean T. stramenti isolate are described, illustrated, and compared with the same species from other geographic origins.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.31 no.3
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• pp.71-78
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• 2023

To minimize the occurrence of aviation accidents in the post-COVID, continuous flight training is crucial. However, the current infrastructure of domestic airports and airfields is insufficient to prepare for and respond to accidents, and there is a need for sufficient facility capacity. Therefore, this study examines the construction of a regional airport to minimize aviation accidents and selects factors necessary for determining the site location. Among the 11 selected factors, six were considered the most important site selection factors, including noise issues, weather conditions, obstacle limitations, environmental issues, airspace conditions, and facility usability. Applying these factors, an analysis was conducted on the Songpo area of Sacheon City, Gyeongsangnam-do. Based on a comprehensive review, it can be concluded that the Songpo area is a suitable choice for a regional airport due to its excellent transportation environment, consideration of noise and environmental issues with the residential population, and other factors. Furthermore, the development of the aviation industry is expected to bring about an increase in tourism and economic benefits, and it is anticipated to make a significant contribution to the domestic aviation industry along with the construction of the currently under-construction Ulleung Airport.

• Mycobiology
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• v.48 no.5
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• pp.351-363
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• 2020

Here, we investigated fungal microbiota in the understory root layer of representative well-conserved geographically segregated natural wetlands in the Korean Peninsula. We obtained 574,143 quality fungal sequences in total from soil samples in three wetlands, which were classified into 563 operational taxonomic units (OTU), 5 phyla, 84 genera. Soil texture, total nitrogen, organic carbon, pH, and electrical conductivity of soil were variable between geographical sites. We found significant differences in fungal phyla distribution and ratio, as well as genera variation and richness between the wetlands. Diversity was greater in the Jangdo islands wetland than in the other sites (Chao richness/Shannon/Simpson's for wetland of the Jangdo islands: 283/6.45/0.97 > wetland of the Mt. Gariwang primeval forest: 169/1.17/0.22 > wetland of the Hanbando geology: 145/4.85/0.91), and this variance corresponded to the confirmed number of fungal genera or OTUs (wetlands of Jangdo islands: 42/283> of Mt. Gariwang primeval forest: 32/169> of the Hanbando geology: 25/145). To assess the uniqueness of the understory root layer fungus taxa, we analyzed fungal genera distribution. We found that the percentage of fungal genera common to two or three wetland sites was relatively low at 32.3%, while fungal genera unique to each wetland site was 67.7% of the total number of identified fungal species. The Jangdo island wetland had higher fungal diversity than did the other sites and showed the highest level of uniqueness among fungal genera (Is. Jangdo wetland: 34.5% > wetland of Mt. Gariwang primeval forest: 28.6% > wetland of the Hanbando geology: 16.7%).

• Journal of Navigation and Port Research
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• v.43 no.2
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• pp.79-85
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• 2019

Climate change is a very vital issue that can be no longer avoided. Korea has been a top-level country Iin dealing with carbon dioxide emissions since 1960. Many studies have been conducted to suppress or eliminate carbon dioxide emissions, which account for a large portion of greenhouse gases. Carbon Capture and Storage (CCS), the most practical method of them, plays a significant role. However, these methods have the disadvantage of the limits of geographical distribution and high possibility of re-emission into the atmosphere. Recently, ocean storage has been studied using Accelerated Weathering of Limestone (AWL), a technique for storing carbon dioxide in the ocean as an alternative to CCS, an underground storage. AWL is a method of converting carbon dioxide into concentrated water in the form of bicarbonate ion and discharging it to the ocean to dilute and store it. It does not cause re-emission to the atmosphere, and the discharged concentrated water increases the alkalinity of the ocean to prevent marine acidification. The objective of this study was to understand the behavior of DIC (Dissolved Inorganic Carbon) including carbon dioxide during the ocean discharge of bicarbonate ion concentrated water in AWL method. This study area was set near Ulleung-do where sufficient water depth and operational efficiency were secured. CORMIX model was used to calculate the material diffusion by submerged discharge using ship.

• Korean Journal of Plant Resources
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• v.35 no.1
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• pp.100-108
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• 2022

We found Urtica dioica L., an unrecorded alien plant, in the Han River basin of Korea. U. dioica is considered to be native to Europe, much of temperate Asia and western North Africa. This plant has been introduced to many other parts of the world. In Particularly, it reported as an invasive species from East Asia (Japan), Oceania and South America. This species is distinguished from related Korean taxa of the genus by its unisexual flower and dioecious plant species. In the Neighbor-Joining tree, U. dioica samples from the Han River Park (Sangam-dong, Mapo-gu, Seoul) and Yangjaecheon Stream (Daechi-dong, Gangnam-gu, Seoul) clustered into a clade consisting of a U. dioica s.s. Here, we provide a precise description, illustrations, a key to the related taxa, and photographs of its habitat.

• Journal of Plant Biotechnology
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• v.49 no.3
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• pp.213-221
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• 2022

Wild garlic (Allium victorialis var. platyphyllum, AVVP) is a nontimber forest product used as an edible and medicinal vegetable. AVVP is usually propagated form offspring bulbs but it takes a long time to harvest. Using tissue culture technology could overcome this problem. This study investigated the optimal conditions for shoot multiplication, root growth, and plant growth by scooping AVVP bulbs. AVVP bulbs harvested from Ulleung Island, Korea, the main producer of AVVP, were surface-sterilized and used for in vitro propagation. Shoot multiplication was performed by the scooping method. More than five multiple shoots were induced from scooped tissue in Quoirin and Lepoivre (QL) medium containing plant growth regulators (PGRs); the maximum number of multiple shoots were induced from scooped tissue in QL medium containing 0.45 μM thidiazuron (TDZ) after 16 weeks of culture. Roots were induced directly at the base of the shoots in all treatments. In vitro rooting depended on the type of PGRs, and the best root-inducing treatment was QL medium containing 9.84 μM indole-3-butyric acid (IBA). Plants with in vitro roots were transferred to pots containing artificial soil and successfully acclimatized for 4 weeks. The acclimatized plants showed a survival rate of 80% after 20 weeks and gradually promoted growth depending on the acclimatization period. The results of this study will be of great help to AVVP dissemination through sustainable mass propagation.

• Korean Journal of Environment and Ecology
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• v.33 no.6
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• pp.686-694
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• 2019

This study was carried out to identify the long-term changes to beech forest due to climate change in Ulleung-do. To study the traits of the stand structure of beech forest with micro-topography, we investigated the distribution of the basal area, important values, and indicated species in a small ridge between Albong basin and Seongin-bong peak, and 1-ha stands (20 m × 20 m, 25 sites) dominated beech species including on the upper slope and valley parts. The result showed that the indicator species characterizing the vegetation communities were Tsuga sieboldii, Rhododendron brachycarpum, and Mitchella undulata in the small ridge and Celtis jessoensis, Dryopteris crassirhizoma, and Ulmus laciniata in the valley part. Moreover, the individuals with the total DBH < 10 cm were more predominant in the small ridge and upper slope than in the valley part, the individuals with DBH = 10-25 cm were predominant in the small slope, and individuals with DBH = 25-45 cm and DBH > 45 cm were predominant in the upper slope. The reason for the predominant distribution of beech stand with DBH<10 cm in all terrains is suggested to be germination by nutritional propagation rather than secondary succession caused by artificial disturbances and seed propagation.