• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.57 no.3
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• pp.214-227
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• 2021

The distribution of tidal current and tidal induced residual current, topographical eddies and tidal residual circulation in the waters surrounding the Geumo Island-An Island channel were identified through numerical model experiments and vorticity balance analysis. Tidal current flows southwest at flood and northeast at ebb along the channel. The maximum flow velocity was about 100-150 cm/s in neap and spring tide. During the flood current in the neap tide, clockwise small eddies were formed in the waters west of Sobu Island and southwest of Daebu Island, and a more grown eddy was formed in the southern waters of Geumo Island in the spring tide. A small eddy that existed in the western waters of Chosam Island during the ebb in neap tide appeared to be a more grown topographical eddy in the northeastern waters of Chosam Island in spring tide. Tidal ellipses were generally reciprocating and were almost straight in the channel. These topographical eddies are made of vorticity caused by coastal friction when tidal flow passes through the channel. They gradually grow in size as they are transported and accumulated at the end of the channel. When the current becomes stronger, the topographic eddies move, settle, spread to the outer sea and grow as a counterclockwise or clockwise tidal residual circulation depending on the surrounding terrain. In the waters surrounding the channel, there were counterclockwise small tidal residual circulations in the central part of the channel, clockwise from the northeast end of the channel to northwest inner bay of An Island, and clockwise and counterclockwise between Daebu Island and An Island. The circulation flow rate was up to 20-30 cm/s. In the future, it is necessary to conduct an experimental study to understand the growth process of the tidal residual circulation in more detail due to the convergence and divergence of seawater around the channel.

• 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.

• ALGAE
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• v.25 no.4
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• pp.173-182
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• 2010

Four Rhizosolenia species of marine diatom were appeared at 30 sites in Korean coastal waters from September 2008 to February 2010. The cell shape, diameter, length of pervalvar axis, external process, segment and areolation characters of the species were examined. All four species were cylindrically shaped, but the external processes differed. Segment striations were regularly straight, and velum showed hexagonal, circular pore and narrow slit. Rhizosolenia formosa and R. hyalina were only occurred in September 2008 from the Yellow Sea, R. bergonii was appeared throughout the year from Korea Strait and Yangyang coasts, and R. setigera was abundantly showed in all seasons from all site. R. formosa is a newly recorded species in Korean coastal waters.

• Journal of Species Research
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• v.13 no.2
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• pp.178-184
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• 2024

Two species (Lucicutia clausi, L. flavicornis) of Lucicutia (Lucicutiidae Sars, 1902) have been reported in Korean waters and one species(L. gaussae) is newly added the Tsushima Warm Current realm. Specimens from Korean waters are morphologically consistent with previous morphological characteristics of L. gaussae, but these differ in the following characteristics: 1) the male antennule with one process on segments XIX-XX, one process on segment XVIII, and three processes on segments XXI-XXIII; 2) in male leg 5, basis of left leg in the Korean specimen with small spine processes on the protrusion; 3) in male leg 5, the third exopodal segment of left leg without an inner marginal spine. In this study, we provide a redescription of L. gaussae insufficiently described by previous authors.

• Animal cells and systems
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• v.14 no.3
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• pp.213-219
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• 2010

Bottlenose dolphins (Tursiops sp.) commonly inhabit Korean waters, including the coastal waters of Jeju Island. However, their taxonomic position was unclear because of the validity of this genus. The genus Tursiops has recently been determined to comprise two species: the common bottlenose dolphin (Tursiops truncatus) and the Indo-Pacific bottlenose dolphin (Tursiops aduncus). To confirm the taxonomic position of bottlenose dolphins frequenting the coastal waters of Jeju Island, the external morphology and osteology of specimens from Jeju Island were examined. Photographs of free-swimming individuals were also used for determining external morphological characters. The cranial and meristic measurements fell within the ranges of T. aduncus. Osteological ratios were also consistent with those of T. aduncus. The presence of a prominent ventral spot was observed among some individuals. As a result, the dolphins mainly distributed in the coastal waters of Jeju Island were identified as Indo-Pacific bottlenose dolphins (T. aduncus) in terms of their cranial characters and ventral spotting. We propose a new Korean name, 'Nambang-keun-dol-go-rae'.

• Korean Journal of Ichthyology
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• v.36 no.1
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• pp.84-93
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• 2024

The sharks identified in the coastal waters of Korea are known to date to 9 Orders, 21 Families, 32 Genera and 47 Species. Therefore, recent studies and records of shark appearance in Korean waters were reviewed and organized. As a result, Halaelurus buergeri was separated from the Family Scyliorhinidae into the Family Pentanchidae based on the supraorbital crest absent on cranium above eyes. Accordingly, compared to the previous study, Family Pentanchidae, Genus Hexanchus, and 2 Species Hexanchus griseus and the Alopias superciliosus were added, resulting in a total of 49 species of sharks in 9 Orders, 22 Families, and 33 Genera in coastal waters of Korea. A list of these species, a search table, and the history of scientific name changes are provided, and proposed a new Korean name of 'Bul-beom-sang-eo-gwa' of the Family Pentanchidae.

• Economic and Environmental Geology
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• v.41 no.1
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• pp.15-32
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• 2008

The hydrochemical and isotopic (stable isotopes and noble gas isotopes) analyses for hot spring waters, cold groundwaters and surface water samples from the Seokmodo hot spring area of the Ganghwa province were carried out to characterize the hydrogeochemical characteristics of thermal waters and to interpret the source of thermal water and noble gases and the geochemical evolution of hot spring waters in the Seokmodo geothermal system. The hot spring waters and groundwaters show a weakly acidic condition with the pH values ranging from 6.42 to 6.77 and 6.01 to 7.71 respectively. The outflow temperature of the Seokmodo hot spring waters ranges from $43.3^{\circ}C\;to\;68.6^{\circ}C$. Relatively high values of the electrical conductivities which fall between 60,200 and $84,300{\mu}S/cm$ indicate that the hot spring waters were mixed with seawater in the subsurface geothermal system. The chemical compositions of the Seokmodo hot spring waters are characterized by Na-Ca-Cl water type. On the other hand, cold groundwaters and surface waters can be grouped into three types such as the Na(Ca)-$HCO_3$, Na(Ca)-$SO_4$ and Ca-$HCO_3$ types. The ${\delta}^{18}O\;and\;{\delta}D$ values of hot spring waters vary from -4.41 to -4.47%o and -32.0 to -33.5%o, respectively. Cold groundwaters range from -7.07 to -8.55%o in ${\delta}^{18}O$ and from -50.24 to -59.6%o in ${\delta}D$. The oxygen and hydrogen isotopic data indicate that the hot spring waters were originated from the local meteoric water source. The enrichments of heavy isotopes ($^{18}O\;and\;^2H$) in the Seokmodo hot spring waters imply that the thermal water was derived from the diffusion Bone between fresh and salt waters. The ${\delta}^{34}S$ values ranging from 23.1 to 23.5%o of dissolved sulfate are very close to the value of sea water sulfate of ${\delta}^{34}$S=20.2%o in this area, indicating the origin of sulfate in hot springs from sea water. The $^3H/^4He$ ratio of hot spring waters varies from $1.243{\times}10^{-6}\;to\;1.299{\times}10^{-6}cm^3STP/g$, which suggests that He gas in hot spring waters was partly originated from a mantle source. Argon isotopic ratio $(^{40}Ar/^{36}Ar=298{\times}10^{-6}cm^3STP/g)$ in hot spring waters corresponds to the atmospheric value.

• 한국해양학회지
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• v.8 no.2
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• pp.61-67
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• 1973

The small shrimp of the genus Acetes which is abundantly distributed in shallow waters along the western coast of Korea has long been considered as Acetes japonicus Kishinouye. In the other hand Liu(1956) has suggested that A. chinensis was possibly distributed in Korean waters, judging from the information from Yoshida(1941), but none of the specimen was collected from this area. After careful examination of the specimens of Acetes collected from the station (37$^{\circ}$39'N, 126$^{\circ}$23'E) in Sokmo channel, central part of Korea authors agreed that the population distributed in this area is consists of Acetes chinensis Hansen. In the present paper the diagnosis of Korean species of Acetes chinensis has first described with taxonomic revision and it is the new record for Korean waters.

• Korean Journal of Environmental Biology
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• v.40 no.4
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• pp.631-640
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• 2022

Labidocera pavo Giesbrecht, 1889 and L. sinilobata Shen and Lee, 1963, belonging to the detruncata group in the genus Labidocera were collected from the southwestern coastal waters of Korea, using a Norpac net (0.2 mm mesh size). Labidocera sinilobata, known to be endemic species in estuary of Chinese rivers, is the first record in Korean waters. In Chinese waters, this species has only been briefly documented and illustrated. In the study, their morphological characteristics were fully redescribed with careful examination of the fine epidermal structure using a SEM (Scanning Electron Microscope) in addition to their illustrations and compared with species of the detruncata species-group.

• Fisheries and Aquatic Sciences
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• v.26 no.7
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• pp.455-459
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• 2023

40 species of the family Caprellidae Leach, 1814 are recorded in Korean waters. Caprella aino Utinomi, 1943 was newly collected from seaweed farms from the southeastern waters of Korea. C. aino was firstly reported in Japanese waters in 1943. Adults of C. aino and Caprella mutica Schurin, 1935 are easily distinguished in that C. aino have pereonite II and gnathopod II without setae and two small tubercles of articulation of gills in pereonite III-IV, while C. mutica do pereonite II and gnathopod II covered with setae and those of pereonites III-VII with many tubercles. However, subadult C. mutica is hardly distinguishable from C. aino in that tubercles of pereonite III are less developed and they have inconspicuous setae of pereonite II and gnathopod II. Nevertheless, C. aino is distinguished from subadult C. mutica because adult C. aino have dorsal tubercles on pereonite IV, V, VI, VII unlike that of C. mutica. We report C. aino as a new record in Korean water with comparison of C. mutica.