• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.4
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• pp.401-409
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• 1983

The distribution of anchovy eggs and larvae was studied using the ichthyoplankton samples and oceanographic data collected in the western and southern waters of Korea over the period of April through June in 1981 and 1982. Three water masses, the Tsushima Warm Current, the South Korean Coatal Water and the Yellow Sea Bottom Cold Water, are found to exert extensive influences of the distribution of anchovy eggs and larvae. The Tsushima Warm Current contacts with the South Korean Coastal Water to produce a coastal front between Cheju Island and Tsushima Island in the southern waters of Korea. Off the west coast of Korea, a coastal front is also formed running parallel with the western coast-line of Korea in the area between the Yellow Sea Bottom Cold Water and the extended part of the South Korean Coastal Water. In the southern waters of Korea anchovy eggs were found chiefly in the coastal waters inside the front, and larvae appeared to both sides on the front. The distribution of anchovy eggs and larvae off the west coast of Korea, however, was limited largely to the coastal waters of more than $12^{\circ}C$ in temperature. In the southern waters of Korea prelarvae appeared in the coastal area, and postlarvae in the offshore area. While in the western waters of Korea prelarvae were found in the southern part of the waters, and postlarvae in the northern part. Anchovy eggs and larvae were distributed in the considerably limited area of the coastal waters off the south coast of Korea in 1981 when the temperature gradient of the coastal front was sharper than in 1982.

• Journal of the korean society of oceanography
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• v.31 no.4
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• pp.196-206
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• 1996

Vertical profiles of the chlorophyll ${\alpha}$, phytoplankton abundance, nutrients and sigma-t were compared with the vertical distribution of phytoplankton species in conjunction with $^{14}$C primary production in the Southern Waters of the East Sea, Korea. In the upper mixed layer the water column was only weakly stratified and ambient nitrogenic nutrient concentrations were markedly depleted. Dissolved silicate seemed to be another limiting nutrient in the surface layer. The occupation of different water depths by several dominant diatom species was well explained by the degree of silicification of each cell and the silicate concentration of ambient seawater. Subsurface chlorophyll maxima were continuously observed in the lower parts of the euphotic layer and the depth coincided with nutricline, supporting our view that chlorophyll maximum was sustained partially by enhancement of in situ growth of phytoplankton and partially by increase of cellular chlorophyll content. The persistence of chlorophyll maximum layer was attributed to the physiological adaptation of the phytoplankters to low light intensities and to the utilization of regenerated nutrients. Integrated water column production of organic matter by photosynthesis appeared to be better related to phytoplankton cell division than to the cell growth in terms of biosynthesis of pigments and other intracellular components.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.3 no.1
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• pp.29-37
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• 1991

A two-dimensional numerical model. using finite element method. was applied to calculation of the tides and tidal currents of four major tidal constituents($M_2, ;S_2, ;K_1, ;O_1$) in the southern part of the East Sea. The model results were compared with the observed data and with the existing tidal charts. and the computed results showed good agreement with the observation. As a result, the detailed tidal charts for four major tidal constituents and the tidal current ellipses of the M$_2$and $K_1$tides were produced respectively. The results indicate that the amphidromic point of diurnal tide locates near Korean coastal lines closer than that of the chart drawn by Nishida(1980).

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.47 no.3
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• pp.194-202
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• 2011

Maturation and spawning of the Shotted halibut, Eopsetta grigorjewi was investigated based on the samples captured in South Korean waters from January 2008 to December 2009. Gonadosomatic index began to increase in December, and reached maximum between January to March. After spawning it began to decrease from May. Reproductive season was estimated to January-April, with peak in February. Fecundity was proportional to the size of the female, with the clutch size varying from 170,000 eggs in the smallest female (total length, 28.9cm) to 1,300,000 eggs in the largest (total length, 41.5cm). Size at 50% sexual maturity (TL50), determined from mature females, was 28.8cm. Annual reproductive cycles of this species could be divided into six successive stages; immature stage (May-October), nucleolus stage (November-January), yolk vesicle stage (January-February), vitellogenic and ripe stage (January-April) and spent stage (April-May).

• Journal of fish pathology
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• v.10 no.2
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• pp.137-142
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• 1997

A monogenean gill parasite, Prosomicrocotyla gotoi, and a digenean intestinal fluke. Opecoelus sphaericus, were found from greenilngs (Hexagrammos otakii) captured at the Korean southern sea. P. gotoi was characterized by having two separated frills of opisthaptor and distinguished from P. chirii in testis and clamp numbers. O. sphaericus had three pairs of finger-like marginal appendages on the ventral sucker and the parasite was distinguished from O. nipponicus in the location pattern of testes. These two helminth species were the first recording species in Korea.

• 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.

• Proceedings of KOSOMES biannual meeting
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• 2003.11a
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• pp.175-180
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• 2003

Water temperature data of National. Fisheries Research and Development Institute (NFRDI) during periods of 19m to 2002 were analyzed to investigate the effect of the water temperature on catches of anchovy and laver in the eastern part of the Southern Waters of Korea The annual catches of anchovy and laver increased gradually although they showed fluctuations each year. Our findings indicated tint the catches cf anchovy and laver were controlled by various oceanographic conditions, mainly water temperature. The appearance of cooler sea surface water, warmer water at 0 to 20 m depth, and bottom water of about $15^{\circ}C$ caused relatively lower catches.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.851-855
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• 2013

To determine the status of sunfish fishery, fishing places, body size, weight, etc. were investigated from 2010 to 2012 in Busan Cooperative Fish Market. Most of the sunfish were caught by large purse seine around Jeju island, and the fishing ground of sunfish were reached from Heuksando in the southern Yellow Sea to Guryongpo in the southern East Sea. The range of total length (TL) of the sunfish caught by purse seine was 55-271 cm, and the estimated length-weight relationship was $BW=8E-06TL^{3.3797}$. From the relationship, the weight of 50 cm in total length was estimated to be ca. 4 kg, TL 100 cm was ca 46 kg, TL 200 cm was ca 478 kg, and TL 271 cm was estimated to be 1,336 kg.

• 한국지구물리탐사학회:학술대회논문집
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• 2009.10a
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• pp.113-118
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• 2009

An uplift or a subsidence of a wide area can be derived from change of gravity value, change of geoid, change of heights at measurement points etc. In the past decade, 1) the absolute gravity value acquired at a point in Daejeon decreased, 2) the geoid height on the Yellow Sea Area derived from satellite altimetry data increased, 3) the height of the southern part of Korean Peninsula increased. By synthesizing these, we can interpret that the wide area including the southern part of Korean Peninsula and the Yellow Sea is uplifting with the velocity of about 2 mm/yr.

• Journal of the korean society of oceanography
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• v.33 no.4
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• pp.196-204
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• 1998

$^{14}$C uptake experiments were carried out in and around the cold water mass in the southern part of the Korean East Sea in August and October 1995 to assess spatial and seasonal variability of primary productivity and its relation to physical and chemical factors. The cold and high saline water mass in the bottom layer extended upward to the surface layer and developed along the eastern coast of Korea in August. Chlorophyll-a concentration was maintained high in the cold water mass through August to October and its maximum concentration was 6.3 ${\mu}$g 1$^{-1}$ at Stn. 209-4 in August. Primary productivity and daily primary productivity ranged from 0.29 to 8.02 mgC m$^{-3}$ hr$^{-1}$ and from 58.3 to 63.1 mgC m$^{-2}$ d$^{-1}$, respectively, throughout the study period. Primary productivity of the cold water mass was higher than that of offshore waters in both summer and autumn seasons. P$_{max}$ and I$_{max}$ of the cold water mass in August were higher than those in October, except Stn. 208-5. These results suggest that high primary productivity in the cold water mass may be established by the upwelled nutrients and light adaptaion to convected phytoplankton due to upwelling of the bottom waters.