• The Korean Journal of Malacology
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• v.28 no.3
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• pp.259-267
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• 2012

Due to the oil spill incident in December 2007, every facility of oyster culture was removed in western coast especially in Taean and Seosan. To restore oyster resources in Taean and Seosan, we brought oyster seeds from southern area and monitored their growth. In addition we monitored the culture environment throughout the year, and observed the number of oyster larvae and attached spats on collectors during summer. The factors of water environment were appropriate for oyster culture in both study area. The growth of shell height was larger in Uihang-ri, Taean than Jungwang-ri, Seosan. Spawning was more intensive in a short time in Jungwang-ri, Seosan than Uihang-ri, Taean. The number of oyster larvae and spats of collectors were much more in Jungwang-ri, Seosan than Uihang-ri, Taean. This study showed that transplantation of healthy oyster seeds from southern area can be a way of restoration of oyster resources in western coast. In addition, systematic approaches are necessary by building a better understanding of regional characteristics to restore and enlarge the oyster culture farms in western coast. In summary Uihang-ri, Taean will be appropriate for cultivation farms and Jungwang-ri, Seosan for seedling grounds to increase oyster culture productivity.

• Journal of Korea Port Economic Association
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• v.17 no.2
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• pp.61-87
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• 2001

The purpose of this paper is to analyze the location, population growth. and cargo concentration of Korean port-cities. In the location theory, Sommer (1976) and McGee (1967) models are newly introduced, as are the Rimmer (1967), Bird (1965), Hoyle (1981) models. which were already introduced in previous studies from Korea. Analysis of population growth in the Korean port-cities is conducted using data from 1966 to 1998. Rimmer and Hoyle's concentration models are used to measure cargo concentration from 1966 to 2000. The main results of this paper are as follows: First, Korean ports are concentrated on the East Sea, the Southern Sea, and the West Sea. Their locations are closely related with the hinterland. the inland city, and growth of port-cities. In considering the foreign countrys' cases, Korean port-cities are similar to the models of Bird and Hoyle. Second, the populations of Ulsan and Pohang grew at the fastest rate in 1966-1998, while the port cities in the Honam and Jeiu region grew at much lower ratios. Most port cities are located near large industrial complexes. Third the growth rates of Gwangyang, Daesan, Pohang, Pyungtaeg, and Samchunpo increased, while those of Busan. Mukho, Masan, Mogpo, Yeosu, and Sokcho declined. Of particular note, the growth rate of Busan remained negative after the late 1980s. Fourth. empirical results using the Rimmer (1967) model indicate that Gwangyang, Daesan, Pyungtag, and Pohang have shown the concentration. But the deconcentration was shown from the Busan, Mukho, Janghang, Gunsan, Mogpo, Yeosu, Masan, Sokcho. and Jeju. Fifth, the concentration of ports located in West coast region has shown the mixed results between concentration and deconcentration except the concentration of early 1970s and 1990s. The concentration of ports located in East coast region has shown the concentration before the middle of 1980s. And deconcentration after the middle of 1980s have appeared. The Southern coast region has shown the continuous deconcentration except the partial concentration of early 1986. and 1991. Planners of Korean ports should find out the factors of concentration and deconcentration of each ports and should determine factors such as investment priority level. size and scope in order to ensure the balanced development of regional ports and port-cities.

• Korean Journal of Environmental Biology
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• v.21 no.2
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• pp.101-113
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• 2003

The spatial distributional pattern of macrobenthic fauna was investigated to assess the summer benthic environmental conditions in Gwangyang Bay, the southern coast of Korea. The macrobenthic faunal community from 38 sites in Gwangyang Bay comprised 154 species and showed an overall mean density of 1,280 individuals $m^{-2}$. Polychaetes were the most important component of the macrofaunal community in species richness, abundance and biomass. The dominant species in abundance were polychaetes like Tharyx sp. (44.8%), Lumbrineris longifolia (14.0%), Heteromastus filiformis (3.6%), a mussel Mytilus edulis, and an amphipod crustacean Corophium sinense. The abundance and biomass in the western part of the bay were lower than those in the channel regions and mouth of the bay. The community indices showed the same trend in the spatial distribution with the abundance and species richness. All macrobenthic faunas were assigned into a specific functional group according to their ecological responses to the environmental stress. The benthic community health based on the Benthic Pollution Index (BPI) or Biotic Coefficient (BC) seemed to be in the normal to unbalanced er transitional condition, indicated by the dominance of small polychaete worms like Tharyx sp. in the mouth part of the bay.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.6 no.3
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• pp.164-179
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• 2001

Spatio-temporal variation in species composition, abundance and distribution of fisheries resources caught by large purse seine off Korea from 1991 to 1994 was analysed. Out of 19 species, Scomber japonicus (54.7%), Sardinops melanostictus (20.4%), Trachurus japonicus (9.1%), and Scomberomorus niphonius (6.2%) were predominated in catch. These 4 pelagic fishes occupied 90% of total catch. Major pelagic fishes caught by large purse seine were dispersed to northward from spring to summer, and migrated to the southern wintering ground during winter. Fishing effort (number of haul) was high in summer, but catch per unit effort showed a peak in winter. The high CPUE in winter seemed to be related to aggregation of the pelagic fish to the wintering ground in the southern sea. After spawning, they were widely dispersed for feeding in warm months.

• Economic and Environmental Geology
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• v.37 no.2
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• pp.255-267
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• 2004

Deep-sea surface sediments acquired by multiple corer from 69 stations in the Clarion-Clipperton fracture zone of the northeast equatorial Pacific, were analyzed for shear strength properties to understand sedimentological process. The pelagic red clay from northern part of study area shows low average shear strength(4.4 kPa), while the siliceous sediment from middle area shows high(6.3 kPa). The calcareous sediment from southern area shows very low average shear strength(3.4 kPa), and transitional sediment between middle and southern area shows intermediate value(3.8 kPa) between siliceous and calcareous sediment. The depth profiles of average shear strength of pelagicred clay show gradual increment with depth due to decrease of water content with depth by general consolidation process. On the other, abrupt increment of average shear strength with depth in siliceous sediment is related to sedimentary hiatus. The very low shear strength in calcareous sediment is linked to very high sedimentation rate ofsouthern area compared with other study area.

• Korean Journal of Ichthyology
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• v.27 no.4
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• pp.310-316
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• 2015

The seasonal and interannual variation in the species composition and abundance of the fish assemblage were studied. Fish samples were collected seasonally over 4 year (2005 to 2008) using pots in the southern coast of East Sea. During the study period, a total of 32 fish species belonging to 24 families were collected. The dominant species were Conger myriaster, Paracentropogon rubripinnis, Liparis tanakae, Parapercis sexfasciata, Eptatretus burgeri and Clupea pallasii pallasii, which accounted for 91.9% of the total number of individuals collected. The number of species, number of individuals, biomass, and diversity fluctuated with season. The peak number of species and number of individuals occurred were in August 2008, whereas the biomass was the highest in August 2005 and diversity was in May 2008. The abundance of dominant species also showed some seasonal and interannual changes. A one-way analysis of similarity (ANOSIM) showed that the fish assemblage in 2008 was significantly different from those of 2005, 2006 and 2007, whereas there was no significant difference among seasons over 4 years.

• Journal of the Korean earth science society
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• v.28 no.5
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• pp.585-597
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• 2007

The characteristics of the rainfall events on the Korean peninsula have been investigated by means of regional and global observational data collected from 1954 to 2004 with an emphasis on extreme cases $80\;mm\;day^{-1}$. According to our analysis, long-term annual rainfall anomalies show an increasing trend. This trend is pronounced in the month of August, when both the amount of monthly rainfall and the frequency of extreme events increase significantly. Composite maps on August during the 8 wet years reveal warm SST anomalies over the eastern Philippine Sea which are associated with enhanced convection and vertical motion and intensified positive SLP over central Eurasia during August. The rainfall pattern suggests that the most significant increase in moisture supply over the southern parts of China and Korea in August is associated with positive SLP changes over Eurasia and negative SLP changes over the subtropical western Pacific off the east coast of south China. The frequent generation of typhoons over the warm eastern Philippine Sea and their tracks appear to influence the extreme rainfall events in Korea during the month of August. The typhoons in August mainly passed the western coast of Korea, resulting in the frequent occurrence of extreme rainfall events in this region. Furthermore, anomalous cyclonic circulations over the eastern Philippine Sea also promoted the generation of tropical cyclones. The position of pressure systems - positive SLP over Eurasia and negative SLP over the subtropical Pacific - in turn provided a pathway for typhoons. The moisture is then effectively transported further north toward Korea and east toward the southern parts of China during the extreme rainfall period.

• Journal of Veterinary Clinics
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• v.19 no.1
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• pp.14-18
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• 2002

An epidemiological study was performed to evaluate the state of fish diseases between aquaculture fishes in the area of southern Kyeongnam, especially Tongyeong-si, Geoje-si, and Goseong-gun. Examination for a total of 91 cases was carried out for a variety of fishes, including Japanese flounder(Paralichthys olivaceus), rock fish (Sebastes schlegeli), sea bass (Lateolabrax japonicus), sea breams(Pagrus major), and red drum (Sciaenops ocellatus) from November, 1999 to October, 2001. The investigation resulted in exploring 155 infectious diseases, including 62 Vibriosis, 16 Edwasiella infection, 11 Streptococcosis, 7 Pseudotuberculosis, 15 Scuticociliatida infection, 20 Gill flukes, and 9 Trichodiniasis. When the infections were classified according to fish species, Japanese flounder was infected by 30 Vibrio spp., 16 Edwardsiella tarda, 6 Streptococcus spp., 12 Scuticociliatida infection. In case of sea bass, 10 Vibrio spp. was able to isolate out of 10 outbreaks, on the other hand, rock fish was dominantly infected by gill flukes since it was observed 12 out of a total of 20 cases. With reference to seasonal fluctuation, Vibrio spp. infection was continually observed through all seasons but Edwardsiella septicaemia, Streptococcosis and Pseudotuberculosis was mainly isolated in summer and autumn when the water temperature was raised high. Scuticociliatida infection was frequently occurred from late autumn to early spring but gill flukes were watched all the year regardless of temperature. As regards, multiple infection, 47 out of 91 cases was Identified to have involved in more than 2 pathogens, especially Vibrio spp. was highly mixed with other pathogens since 42 out of 47 cases was mixed with Vibrio spp.

• Journal of the korean society of oceanography
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• v.36 no.1
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• pp.19-26
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• 2001

The biological pump is one of the important pumping mechanisms absorbing CO$_2$ from the atmosphere into the ocean and can be quantified by estimating new production. New production in the open ocean mostly depends on the supply of nitrate from the water below the mixed layer. While nitrate is affected by many biological processes, the helium isotope ($^3$He) is inert and has very simple physical properties. Using the $^3$He flux and the relation between $^3$He and NO${_3}\;{^-}$- within the thermocline, the nitrate flux supporting new production was estimated in the southern East Sea. The average ${\delta}^3$He within the mixed layer was -14$%_o$ and -l5.4$%_o$ in the winter and autumn, respectively. Through the year excess $^3$He occurs in the mixed layer except for a slight depletion of -17$%_o$ in summer. The $^3$He flux of 13$%_o$md$^{-1}$ associated with the concentration gradient at the air-sea interface was calculated from the product of the piston velocity and the excess $^3$He. Tritium decay within the mixed layer could support only 2$%_o$md$^{-1}$ of the flux. Thus, the remaining 11$%_o$md^{-1}$ could be attributed to the flux of tritiugenic $^3$He from the water below the mixed layer. Nitrate and $^3$He were positively correlated within the thermocline layer with the slope of 0.21 ${\mu}$mol kg$^{-1}$ $%_o\;^{-1}$. The annual nitrate flux estimated from the upward flux of $^3$He and the NO$_{3}\;{^-}$-$^3$He relation was 0.8${\pm}$0.2 mol(N) m$^{-2}$yr$^{-1}$. This flux corresponds to an annual new production of 64 g(C) m$^{-2}$yr$^{-1}$, which is consistent with that in the north-west Pacific.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.17 no.2
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• pp.105-108
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• 1981

The oceanic effect on the climate of the southern coast of Korea was analysed based on the sea surface temperature and in order to study relationships between the fluctuation of the sea surface temperature and that of climatic elements. Meteolorogical data from 1960 to 1979 were used. In the year when difference between the air and water temperature was maximum, the air temperature in southern coast was higher than normal year. A fluctuation of the sea surface temperature plays an important influence to determine the variation of the air temperature in the coastal area. Humidity of the coastal climate depends upon the oceanic effect in summer, but not in winter. This results may be due to prevailing wind effect. The oceanic effect on the precipitation in the coastal area is not found.