• Korean Journal of Environmental Biology
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• v.33 no.2
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• pp.170-176
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• 2015

Oncholaimid nematode, Oncholaimus secundicollis Shimada, Kajihara and Mawatari, 2009, is firstly reported based on a comparative morphological study. The present specimens of O. secundicollis are collected from rocky intertidal seagrass on the eastern coast of Korea. Oncholaimus secundicollis is distinguished from all of its congeners by the following combination of morphological characteristics: buccal cavity large with thick cuticular wall and three teeth, left subventral tooth larger than right subventral or dorsal teeth, and the presence of two remarkable precloacal papillae with nine pairs of cloacal setae and single ventral tail papilla with two pairs of short setae. In this study, we provide taxonomic description and illustration of unrecorded species of the genus Oncholaimus.

• Animal Systematics, Evolution and Diversity
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• v.24 no.3
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• pp.251-263
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• 2008

Eight species and four genera belonging to two families of antipatharians have been reported in Korea. In the present study, the major specimens were collected from the coastal areas of Jejudo Island from 2005 to 2006, and the other ones which have been deposited in the Natural History Museum and the Department of Life Science, Ewha Womans University during the period from 1965 to 2004 were reexamined. As a result of this work, four species, Myriopathes bifaria, M. stechowi, M. ulex and Plumapathes pennacea are new to Korean antipatharian fauna. In this study, total six species including previously recorded species of the family Myriopathidae were described. And the distribution range of Myriopathes lata was turned out to be expanded from southwestern sea to the eastern sea, up to Ulleungdo Is. of Korea. Especially, the sexuality and the gonadal stage of M. lata which are collected during their reproduction period were also determined by means of histological analysis.

• Journal of the Korean Institute of Navigation
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• v.18 no.1
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• pp.23-30
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• 1994

By use of the Climatological Report(1982~1991) and the Marine Casualty Report(1982`1992), marine casualties caused by meteorological factors and climatic characteristics along Korean coast were analysed. Marine casualty by meteorological factors can be classified into three kinds such as collision, aground and sinking. On the whole collision was mainly caused by dense fog and heavy precipitation, and aground and sinking was caused by strong wind and high sea. As results of analysis of the distribution of wind, fog and precipitation at major ports in Korea, climatic characteristics along Korean coast are as follows. in the eastern coast, wind was relatively weak and fog was not so frequently formed, while strong wind blew all the year round and fog appeared from April to August in Ulleung Island. In the southern coast, the wind was strong in both winter and summer, fog formed frequently in late spring through mid-summer and heavy precipitation was in summer. Typhoon affecting Korea was usually passing this area to the East Sea. In the western coast, strong wind was prevailing in winter at southern region and fog was formed very frequently throughout the year.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.1
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• pp.79-83
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• 2014

Thirty five juveniles belonging to the genus Collichthys were collected using a bag net at Gang-wha-do, in the eastern Yellow Sea, between July and September, 2012, and identified using combined genetic and morphological methods. We sequenced 316 base pairs of mitochondrial DNA cytochrome c oxidase subunit I of 35 individuals, of which 22 individuals were identified as Collichthys niveatus (12.9-47.6 mm in SL) and 13 as Collichthys lucidus (13.4-40.3 mm SL). Morphologically, the number of occipital crests, an important taxonomic character during the adult stage, could not distinguish the two species during the juvenile stage, but the shape of the first anal fin spine clearly distinguished the two species even among juveniles.

• Proceedings of the KSRS Conference
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• v.1
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• pp.344-347
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• 2006

China Coastal Water (CCW) usually appears in the seas surrounding Jeju Island annually (June?October) and is very pronounced in August. The power spectrum density (PSD), sea level anomalies (SLAs), and sea surface temperatures (SSTs) were found to peak annually and semiannually. The peaks at intervals of 80-, 60-, and 43-days are considered to be influenced by CCW and the Kuroshio Current. Generally, low-salinity water appears to the west of Jeju Island from June through October and gradually propagates to the east, where CCW meets the Tsushima Current. Empirical orthogonal function (EOF) analysis of SLAs and SSTs indicated that the variance in SLAs and SSTs was 55.70 and 98.09% in the first mode, respectively. The PSD for the first mode of EOF analysis of SLAs was stronger in the western than in the eastern waters because of the influence of CCW. The PSD for the EOF analysis of SSTs was similar in all areas (the Yangtze Estuary and the waters to the west and east of Jeju Island), with a period of approximately 260 days.

• Journal of Species Research
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• v.5 no.3
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• pp.503-513
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• 2016

Two unrecorded marine nematode species, belonging to genus Paracanthonchus Micoletzky, 1924, are described on the basis of the specimens collected from rocky intertidal seagrass bed on the eastern coast of Korea. Paracanthonchus macrodon (Ditlevsen, 1918) is characterized by presence of cuticular differentiation, strongly dilated gubernaculum with numerous cusps, three post-cloacal setae, and arrangement of six (4+2) precloacal supplement. Paracanthonchus kamui Kito, 1981 is distinguished from other species of the genus by having the 4.25 turns amphideal fovea, six tubular supplement, rib-shaped gubernaculums with proximally hook-shaped and distally broaden. In this study, we provide taxonomic description and illustration of two unrecorded species of the genus Paracanthonchus by differential interference contrast microscopy. This is the first report on the species of the genus Paracanthonchus from Korea.

• The Korean Journal of Malacology
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• v.18 no.1
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• pp.27-40
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• 2002

Beach death assemblages of bivalve mollusks were studied with respect to their species composition in six localities along the eastern coast of Korea (Gangneung, Jumunjin, Daejin, Gallam, Jukbyeon, Hupo and Chooksan). In all, thirty-nine species belonging to 30 genera and 19 families were recorded, and species diversity between the sampling sites varied from 5 to 21. Biogeographical analysis showed that studied fauna has warm-water character with the predominance of subtropical and subtropical-lowboreal species and the presence of tropical-subtropical species (in total, 77 %), and only 23 % of mollusks found are cold-water and temperate species. The most abundant species were Septifer virgatus (Wiegmann, 1837), Mytilus galloprovinciallis Lamarck, 1819, Gomphina melanaegis Romer, 1861, Ruditapes philippinarum (Adams et Reeve, 1850), Mactra chinensis Philippi, 1847 and Spisula sachalinensis (Schrenck, 1862).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.6
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• pp.311-322
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• 1988

Application of the simple buoyancy adjustment model, similar to Davey's (1983), indicates that buoyancies imposed locally or from outside of the basin are the major factor of the Japan Sea circulation. Within the context of the model considered, the relatively strong SW gradient of temperature, and corresponding western boundary current, in the SW region is due to the beta-effect. Kelvin waves make the western side colder and the eastern side warmer. Buoyancy input (presumably by fresh water discharge) in the NW region, so far neglected, plays an important role in strengthening the NKCC (North Korea Cold Current) and suppressing the EKWC (East Korea Warm Current) thereby breaking the conventional branching system of the Tsushima Warm Current.

• Journal of the korean society of oceanography
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• v.37 no.3
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• pp.196-200
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• 2002

The time variation in the Kuroshio is studied by use of nine observed distances of the main Kuroshio axis from the Japanese coast. The observed distances over 1975 - 1995 are estimated from the Prompt Report of Oceanographic Conditions published by Hydrographic Department of the Maritime Safety Agency of Japan. It is shown that large sea level difference between Naze and Nishinoomote, which represents the volume transport of the southern inflow south of Kyushu, coincides with larger distance of the Kuroshio in the upstream area from off Kyushu to off eastern Kii Peninsula and smaller distance in the downstream area from off Omae-zaki to off Boso Peninsula. In contrast, large sea level difference between Nishinoomote and Aburatsu, which represents the volume transport of northern inflow south of Kyushu, corresponds to smaller distance in the upstream area and larger distance in the downstream area. Path dynamics of the Kuroshio is discussed with reference to the variation in Volume transport south of Kyushu.

• Ocean Science Journal
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• v.40 no.3
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• pp.119-125
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• 2005

Qualitative and quantitative composition of meiobenthos was studied in Amursky Bay (Peter the Great Bay, the East Sea). Ten taxonomic groups were found, where nematodes were dominant. Density of meiobenthos in ground sediments of the Bay were not uniform, and the average density was measured at $126.4{\pm}62.3ind.mo^{-2}$. 56 species of nematodes were detected, and dominant species were Sabatieria palmaris, Paracanthonchus macrodon, Sphaerolaimus limosus, S. gracilis and Oncholaimium ramosum. Five taxocenes of nematodes were allocated based on the results of cluster analysis and species domination according to density. Low diversity in species composition of nematodes was noted in the northwestern part of the Bay, which is a zone of desalination, and in the eastern part, which is exposed to household drains.