• Journal of fish pathology
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• v.25 no.3
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• pp.165-172
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• 2012

Vibrio alginolyticus (V. alginolyticus), which is one of bacterial pathogens evoking severe infection in fish and shellfish as well as in human has been found at high frequency around all coast areas in Korea. Both V. alginolyticus and V. alginolyticus specific bacteriophage were isolated from sea water and various fishes from fish farms on west coast in Korea. In a morphological study based on electron microscope, the purified phage appeared to be composed of hexagon head of 60 nm and short tail of 20 nm. In the denatured SDS-PAGE analysis, the structural proteins of the phage were found to be 7 different protein fractions ranging from 37.8 to 198 kda. The kind of nucleic acid of the phage was ascertained to a double stranded DNA.

• Journal of the Korean earth science society
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• v.28 no.3
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• pp.357-366
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• 2007

In Gomso Bay, on the west coast of Korea, the surface sediments sampled in 1991 and 2006 were analysed to identify the long-term variations of tidal flat sediments. Silt and clay contents have decreased in the bay-mouth tidal flats whereas sand and clay contents have decreased on the inner-bay and bay-head tidal flats over the last 15 year period. In particular, the clay contents of the tidal flats in 2006 were relatively low when compared to those of both tidal flats adjacent to other semi-enclosed bays and those of the tidal flats in 1991. The variations of textural compositions in the tidal flat sediments have led to changes of the sedimentary facies. It indicates that the changes must have been made by the changes of hydrodynamic conditions impacted by human activities, such as the construction of sea-walls, land reclamation, structures of farms constructed compactly near the low water line, and the Saemangeum dyke constructed in the northern part of the area where this research was conducted.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.886-891
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• 2013

We analyzed surface sediments to explain the substrate characteristics of sea cucumber Stichopus japonicus habitat. The analyses included grain-size determination, water content (WC), loss on ignition (IL), chemical oxygen demand (COD), and acid volatile sulfide (AVS) content. We obtained data on sea cucumber density, weight, and length at each station in a marine farming area in the middle of Korea's Taean coast on the West (Yellow) Sea in May, 2012. The apparent density of S. japonicus was high in coarse and bimodal sediments, whereas it was low in fine and unimodal sediments. The mass of S. japonicus was greater in fine than in coarse sediments, showing a different trend from sea cucumber density. The values for WC, IL, COD, and AVS in surface sediments were higher in areas with high densities of S. japonicus than in areas with low sea cucumber densities. In particular, the concentration of AVS was much higher than the value proposed in Japanese criteria for areas with high S. japonicus density.

• Journal of the Korean Society for Marine Environment & Energy
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• v.15 no.2
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• pp.89-100
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• 2012

The aim of this study knows to occurrence characteristics and monthly transition of foreign marine debris by changing in the marine environment for the national marine debris monitoring areas in the west coastal area. The Jeju Island (5,112) had the highest number for foreign marine debris flowed in the coast. Many areas in the next were surveyed by Hajo Island (1,967), Imja Island (507). Plastic bottles were the most common type to 2,925 piece of the whole collection. Then, the monthly occurrence amount was concentrated in July, September. At this time, analysis results of the marine environment are as follows: The sea surface wind of southerly or southeasterly were predominated. In addition, the sea surface circulations were dominated by inflow of seawater southward along the China Coast and northward from the East China Sea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.6
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• pp.662-668
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• 2017

This study investigated the antimicrobial resistance patterns of Escherichia coli and Vibrio parahaemolyticus isolated from oysters Crassostrea gigas, short-necked clams Ruditapes philippinarum and corb shells Cyclina sinensis from the West Coast of Korea from June through November 2013. The antimicrobial susceptibility patterns of the isolated strains of E. coli and V. parahaemolyticus to 12 antimicrobial agents used in Korea for clinical or veterinary therapy were analyzed. Antimicrobial resistance to at least one antibiotic was seen in 52.0% of the E. coli isolates (156 strains) and 44.3% of the V. parahaemolyticus isolates (194 strains). The resistance of the E. coli (34.0%) and V. parahaemolyticus (41.8%) isolates to ampicillin was highest. Multiple antimicrobial resistance against at least three antimicrobials was seen in 9.0% of the E. coli isolates and 1.0% of the V. parahaemolyticus isolates.

• Journal of Ocean Engineering and Technology
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• v.21 no.1 s.74
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• pp.7-17
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• 2007

Based on the Boussinesq wave model, the wave distribution in the Chagui-Do sea area in Jeju was simulated by applying the directional irregular waves at an incident boundary. The time and spatial variations of monthly mean wave height and period were investigated, which aims to provide basic information on optimal sites for wave power generation. The grid size and time interval of the Boussinesq wave model were validated by examining wave distributions around a surface piercing wall, fixed at sea bottom with a constant slope. Except for the summer season, the significant wave height is dominated by wind waves and appears to be relatively high at the north sea of Chagui-Do, which is open to the ocean, while it is remarkably reduced at the rear sea of Chagui-Do because of its blocking effect on incident waves. In the summer, the significant wave height is higher at the south sea, and it is dominated by the swell waves, which is contributed by the strong south-west wind. The magnitude of significant wave height is the largest in the winter and the lowest in the spring. Annual average of the significant wave height is distinctively high at the west sea close to the Chagui-Do coast, due to a steep variation of water depth and corresponding wave focusing effect. The seasonal and spatial distribution of the wave period around Chagui-Do sea reveals very similar characteristics to the significant wave height. It is suggested that the west sea close to the Chagui-Do coast is the mast promising site for wave power generation.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.7 no.4
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• pp.247-256
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• 2002

Distribution of surface and suspended sediments was studied to understand sedimentary processes of finegrained sediment near the cooling water intake of Pyongtaek power plant on the west coast of Korea. The grainsize of surface sediment during the winter was coarser in the opened northern area than sheltered southern area. During the summer, finer sediment was found in the east (landward) than west due under dominantly the influence of tidal current. The concentration of suspended sediments was higher in the winter than summer and in the mid- to deep waters than surface waters. Asymmetry of tidal current induced net landward transport of suspended sediments. Landward transport of suspended sediments was most significant at the beginning of flood time when water level is low. Net suspended sediment fluxes ranged from 3.4$\times$10$^{-3}$ kg.m$^{-2}$ .s$^{-1}$ to 5.7$\times$10$^{-3}$ kg.m$^{-2}$ .s$^{-1}$ This large landward transport of suspended sediments is attributable to combination of enhanced flow induced by intake of cooling water and artificial structures near the water intake.

• Journal of Fisheries and Marine Sciences Education
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• v.16 no.1
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• pp.110-123
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• 2004

Five Islands in the West Sea of Korea (Baekryeong-do, Daecheong-do, Socheong-do, Yeonpyeong-do, and Woo-do) are located very close to the North Korea's coast and all of them are under the jurisdiction of South Korea. The North and South Korean naval vessels clashed twice in the West Sea of Korea on June 15, 1999 and on June 29, 2002. These incidents were resulted from conflicts over the validity of the Northern Limit Line(NLL) and the appropriate maritime boundary between the two Koreas. From the viewpoint of South Korea, the North Limit Line is a lawful Maritime Military Demarcation Line under the Korean Military Armistice Agreement and it must be maintained as a maritime boundary between two Koreas until being substituted by a peace treaty. In conclusion, the maritime boundary between two Koreas cannot be settled easily by the principles of the International Law of the Sea at present.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.55 no.3
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• pp.206-216
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• 2019

This study is aimed to compare stock assessment models depending on how the models fit to observed data. Process-error model, Observation-error model, and Bayesian state-space model for the Korean Western coast fisheries were applied for comparison. Analytical results show that there is the least error between the estimated CPUE and the observed CPUE with the Bayesian state-space model; consequently, results of the Bayesian state-space model are the most reliable. According to the Bayesian State-space model, potential yield of fishery resources in the West Sea of Korea is estimated to be 231,949 tons per year. However, the results show that the fishery resources of West Sea have been decreasing since 1967. In addition, the amounts of stock in 2013 are assessed to be only 36% of the stock biomass at MSY level. Therefore, policy efforts are needed to recover the fishery resources of West Sea of Korea.

• Journal of Environmental Science International
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• v.31 no.9
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• pp.767-779
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• 2022

In this study, sediment cores were sampled from tidal flats (six sites) in the west and south coastal wetlands, the blue carbon stock in the tidal flat sediments was calculated, and the blue carbon stock characteristics and influencing factors were analyzed. The sediment particle size of the west coastal tidal flats was larger than that of the south coastal tidal flats, and the organic carbon content in the south coastal tidal flats was more than twice that of the west coastal tidal flats. Blue carbon stock per unit area was 28.4~36.8 Mg/ha on the west coastal tidal flats and 69.8~89.8 Mg/ha on the south coastal tidal flats, which was more than twice higher in the south coastal tidal flats than in the west coastal tidal flats. The total amount of blue carbon stock in the tidal flats was the highest in Suncheon Bay tidal flats at 153,626 Mg, and followed by Gomso Bay tidal flats at 141,750 Mg, Hampyeong Bay tidal flats at 58,420 Mg, Dongdae Bay tidal flats at 44,900 Mg, Cheonsu Bay tidal flats at 36,880 Mg, and Jinhae Bay tidal flats at 26,205 Mg. Blue carbon stock per unit area was higher in the south coastal tidal flats, but the total amount of blue carbon stock in the tidal flats was higher in the west coast. The slope of the regression function of blue carbon stock with respect to the organic carbon content in the tidal flat sediments was estimated to be about 0.05 to 0.07, and the slope of the regression function was higher in the west coastal tidal flats than in the south coastal tidal flats.