• Journal of the Korean Society for Marine Environment & Energy
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• v.8 no.2
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• pp.100-110
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• 2005

We carried oui a study on the marine environment and distribution of phytoplankton community, such as chlorophyll a, species composition, dominant species and standing crops in the Northern East China Sea during early summer of 2004. According to the analysis of a T-S diagram, three characteristics of water masses were identified. We classified them into the coastal water mass, the cold water mass and the oceanic water mass. The first was characterized by the low temperature and the low salinity originated from China territory, the secondary was characterized by the low temperature, the low salinity and the high density originated from bottom cold water of Yellow Sea, and the third was done by the high temperature and salinity originated from Tsushima warm current. The internal discontinuous layer among them was farmed at the intermediate depth (about $5{\sim}30m$ layer). And the thermal front by upwelling region between the cold water mass and Tsushima warm current appeared in the central parts of the South Sea of Korea. The Phytoplankton community in the surface and stratified layers was a total of 44 species belonging to 26 genera. Dominant species were Prorocentrum triestinum, Scrippsiella trochoidea, Skeletonema costatum & Leptocylindrus mediterraneus. Standing crops of phytoplankton in the surface layer fluctuated between $0.3{\times}10^3$ cells/L and $10.8{\times}10^3$ cells/L. Diatoms appeared mainly in the Tsushima warm current regions, and flagellates occurred in the frontal zone and the low salinity regions where was the transfer areas of Chinese continental coastal waters. Chlorophyll a concentration by controlled phytoflagellate ratio in the South Sea of Korea was high values in the frontal zone and sub-surface layer. It was high concentration in the upwelling and coastal waters regions, but low concentration in the Tsushima warm current regions. The Chl-a maximum layers appeared in the thermochline depth or sub-surface layer lower than thermocline. The phytoplankton production in the South Sea of Korea was controlled by the expanded coastal waters of Chinese Continent which include a high concentrations of nutrients.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.1
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• pp.1-9
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• 1999

Hydrographic survey was carried out in the mid-eastern Yellow Sea from Keum River to Taean Peninsula in order to study the motion of the freshwater from the Keum River during July 07-12, 1997 when a large volume of freshwater was discharged from the Keum River weir. The low-salinity (less than 30.0 psu) plume was distributed over the large area between the Keum River and Ochong Island, 60 km northwest off the Keum River mouth. A band of relatively low saline water, originating from the Keum River, was also observed to the north of Ochong Island. The strong haline front had advanced from near Sibidongpa Island to Ochong Island, 25 km northwest of Sibidongpa Island, for 48 hours. A northwestward flow of a speed greater than 0.2 m/s was observed in the surface plume layer to the north of Sibidongpa Island where the water column was strongly stratified. The observed mean flow and the change of the frontal position are interpreted as resulting from the spreading of the Keum River plume. These results suggest that the discharge from the Keum River plays an important role in the coastal circulation of the mid-eastern Yellow Sea adjacent to the river.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.24 no.4
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• pp.237-247
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• 1991

To characterize the community structure and spatial distribution of phytoplankton, observations on seawater temperature, salinity, nutrients, primary productivity and abundance and species composition of phytoplankton were made in the polar front region and its neighborhood off the east coast of Korea in summer 1990. Among the 96 taxa identified, Rhizosolenia setigera and Thalassionema nitzschioides were the most dominant species. The assemblage at the surface and 50 m depth was quite different in the northern inshore part of the study area but similar in the southern and offshore part. Principal component analysis by the species abundance showed that the phytoplankton consisted of the communities representing the surface of the northern inshore part with the neritic-warm dinoflagellates, the Northern Korean Cold Water with the cold water diatoms and the southern and offshore part, which seems to represent the Eastern Korean Warm Water, with the warm water diatoms. At the frontal region, diatoms were mixed with warm and cold water species. Primary productivity and phytoplankton standing crops were higher at the front than the neighboring waters. Nutrients were markedly high at the Northern Korean Cold Water. Horizontal advection of the Northern Korean Cold Water accompanied by nutrient supply seems to contribute to the high phytoplankton biomass at the front.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.38 no.3
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• pp.241-248
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• 2002

The combined hydroacoustic and demersal trawl surveys to investigate the distribution characteristics of fish schools in the Yellow Sea and the East China Sea were carried out during the spring of 1997 by the training ship "Nagasaki Maru" of Nagasaki University. Fish samples were collected by bottom trawling from 9 trawl stations randomly selected in the survey area, and the species and length compositions of trawl catches are examined. Hydroacoustic data were collected by using a Furuno FQ-50 scientific echo sounder operating at 50KHz and the data stored in field were later processed in the laboratory. The results obtained can be summarized as follows ：1. In the 9 trawl surveys conducted in the Yellow Sea and the East China Sea, 78 species including 80 species of fishes, 4 species of Cephalopoda and 6 species of Crustacea, were identified. The most abundant species in these stations were swimming crab(Portunus trituberculatus), Japanese horse mackere(Trachurus japonicus), redlip croaker(Larimichthys polyactis) and the catch per one hour in each station ranged 7.7 to 182.5 kg/hour. 2. The mean volume backscattering strength for the entire water column and the bottom layer of the 0-10 m from bottom friction were -74.6 ㏈ and -68.2 ㏈, respectively. That is, the mean volume backscattering strength for the bottom layer was 6.4 ㏈ higher than that for the entire water column 3. In the surveys during the spring of 1997, the geographical distribution characteristics of fish schools suggests a trend of decreasing fish abundance toward the coast area of Korea and the highest demersal concentrations appeared in waters between the Cheju Island and the Tsushima Island 4. The distribution density of fish school in the East China Sea and Yellow Sea during the 1997 acoustic survey were estimated to be 6.65$\times$10$^{-5}$ kg/㎥ in the entire water column and 2.86$\times$l0$^{-4}$ kg/㎥ in the bottom layer, respectively.pectively.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.3 no.1
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• pp.45-52
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• 1998

The transport of suspended matter was interpreted in the coastal zone off Taean Peninsula during the summer (June) in 1996. Coastal waters were homogenous in water temperature and salinity, whereas offshore waters were characterzed by the strong thermocline. Mixing between coastal and offshore waters are negligeable, largely lessened, due to the existence of strong tidal front between the two water masses. In the offshore area, less saline coastal waters from the Kyunggi Bay are considered to be transported southward along the mid-depth layer of thermocline. Concentration of suspended matters was higher than 5 mg/l in the northern coastal area near the Kyunggi Bay, but generally less than 2 mg/l in the offshore area. Less saline waters along the mid-depth layer in the offshore area sustain maximum turbidities throughout the water column. Therefore suspended matters supplied from the coastal area of Kyunggi Bay are considered to be transported southward by the advective movement of less saline coastal waters. Mean particle size of the suspended matters shows 2~9 ${\mu}m$. Coarse grains (mean size larger than 7 ${\mu}m$) are predominant in the less saline coastal waters extending to the offshore mid-depth waters. Such size distributions of suspended matters together with the characteristics of water masses are considered to be an indicator for the southward movement of suspended matters derived from Kyunggi Bay.

• Journal of the Korean earth science society
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• v.24 no.4
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• pp.303-314
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• 2003

Ocean-air observation using an Automatic Weather Station (AWS) and Conductivity Temperature Depth (CTD) was conducted in the Mid-Yellow Sea off Korea during 8-10 July 2002. A water mass lower than 17$^{\circ}C$ around the Taean peninsula and a tidal front between 36$^{\circ}$20'N and 36$^{\circ}$30'N were observed. The horizontal distribution of air temperature was similar to that of sea surface temperature (SST). Hourly observation around Dukjuk island showed the cold and saline southwesterly and the warm and fresh northeasterly in phase with tidal current. Sea fogs two times formed at 2300 LST 8-0130 LST 9, and 0300-0600 LST 9 July 2002 during the observation period, respectively. During the initial stage of fogs, winds became northeasterly at the speed of 2-4m/s$^{-1}$, and air temperature dropped to 18$^{\circ}C$, as the North Pacific High weakened. The satellite image indicated that sea fogs formed over warm water in the western Yellow Sea and moved eastward toward the observation site, which could be called a steam fog. The fogs dissipated when wind speed and air temperature increased.

• Korean Journal of Environmental Biology
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• v.31 no.1
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• pp.19-36
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• 2013

Physiochemical characters of sea waters during summer flood- and winter dry-seasons and their spatial variations were investigated along the coastal area off the eastern South Sea, Korea. Using the hierarchical clustering method, in this study, we present comprehensive analyses of coastal waters masses and their seasonal variations. The results revealed that the coastal water of the study area was classified into six water masses (A to F). During summer season, the surface water was mainly occupied by the coastal pseudo-estuarine water (water mass B) with low salinity and high nutrients and the river-dominated coastal water (water mass C) with low nutrients, respectively. The bottom water was dominated by cold water (water mass D) with very low temperature, high salinity and high nutrients, compared to masses of surface water. Notably, the water mass B, with high concentrations of nutrients (silicate and nitrogen) and low salinity, which is strongly controlled by the water quality of river freshwater, seems to play an important role in controlling the water quality and further regulating physical processes on ecosystem in the eastern coastal area of South Sea. The water mass D (bottom cold water) coupled with a strong thermocline, which exists in near-bottom layer along the western margin of Korea Strait, has a low temperature, pH and DO, but abundant nutrients. This water mass disappears in winter owing to strong vertical mixing, and subsequently may act as a pool for nutrients during winter dry-season. On the other hand, vertically well-mixed water column during the winter season was typically occupied by the Tsushima (water mass E) and the coastal water (water mass F) with a development of coastal front formed in a transition zone between them. These winter water masses were characterized by low nutrient concentration and balance in N/P ratio, compared with summer season with high nutrient concentrations and strong N-limitation. Accordingly, the analysis of water masses will help one to better chemical and biological processes in coastal area. In most of the study area, characteristically, the growth of phytoplankton community is limited by nitrogen, which is clearly different with coastal environment of West Sea of Korea, with a relative lack of phosphorus. It showed the western and the southern coasts in Korea are substantially different from each other in environmental and ecological characteristics.

• Archives of design research
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• v.13 no.4
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• pp.203-212
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• 2000

If researching popular culture is understanding a mechanism to make us the general public, then researching, design is discovering and developing a mechanism to qualitatively improve the life of the general public's life. Since this means that the relation of popular culture and design is correlated among social, cultural and historical ties, but this study isolated popular culture and design as a separate variable, and examined and analyzed cultural factors such as the constantly changing objective, role, contents and formativeness(Gestaltung) of design through already researched various(6) criteria of the concept of popular culture. Thus, this study strives to present the orientation of design with culture by including cultural thinking starting from the stage of design, design planning.

• 한국해양학회지
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• v.22 no.4
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• pp.217-227
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• 1987

The heat budget of the south eastern region (33$^{\circ}$N-36$^{\circ}$N, 120$^{\circ}$E-125$^{\circ}$E) of the Yellow Sea was calculated by using the meteorological and oceanographical data. The sensibly heat, the evaporation heat and the long wave back radiation have annual variation and increases toward south with strong gradient along the Cheju channel in winter, but they all show tendency to decrease toward eastern coastal area in summer. The area is roughly divided into three parts, the central part, the coastal part and the southern part, according to the characteristics ovariation and distribution patterns of the exchanged heats. The amplitude of the annual variation of total heat exchange in the southern part is very large compare to those of the central and coastal part. The studied area is appeared to be heated mainly by the evaporation heat and the sensoble heat, based on the results of this study.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.3
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• pp.289-296
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• 2002

Using results obtained from field surveys in the outflow region of the Keum River in winter (February 22), spring (May 9), summer (July 31) and autumn (October 17) in 2000, it was described the nutrient front relating to the hydrography. It showed that the horizontal gradients was sharp in the distributions not only in salinity but also in nutrients in the region of the mouth of estuary far away about 20 km from the dyke of the Keum River during the year. The two layer structure was a ubiquitous feature in the inner estuarine side of the region showing the maximum horizontal gradients in salinity and nutrients. Although the absolute values in salinity and nutrient concentrations were distinguished by season, the nutrient front seperates the saltier and nutrients poor water in the open sea from the brackish and nutrients rich water of the plume. These results suggest that the nutrient front coincides with the esturine front in the region of freshwater influence (ROFI) of the Keum River.