• Ocean and Polar Research
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• v.25 no.1
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• pp.1-7
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• 2003

The purpose of this study was to determine changes in the growth rates and the degree of shell bioerosion exhibited by endolithic organisms of the Japanese scallop family, Patinopecten (Mizuhopecten) yessoensis, on the coast of Furugelm Island (Peter the Great Bay, northwest of East Sea = Sea of Japan) over the last three decades. The areas studied are affected by lumen (Tumangang) River run-off, which is enriched by organic matter and polluting agents. It was found that the linear growth rates of the Japanese scallops living along the coasts of Furugelm Island have decreased over the last three decades. The degree of bioerosion of scallop shells has significantly increased for the same period. These phenomena may be explained by a gradual increase in bottom sediment silting, organic enrichment and pollution of the areas being studied. It was found that the degree of scallop shell bioerosion increased with the scallop's age. At present, In each age group, the shells of the scallops sampled from the muddy sand showed greater erosion than the shells of individuals collected from the sandy substrate.

• Animal Systematics, Evolution and Diversity
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• v.9 no.2
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• pp.115-121
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• 1993

Only 12 species of marine harpacticoid copepods are ercorded in Koran waters. With the study on the taxonomy of harpacticoid copepods in Korean waters, Lourinia armata(Claus, 1866) was found in the samples from the rocky shore of Names off the east coast and Chiju Hrbor in June and August 1992, respectively. This species is reported to be distributed in the far east Asian coasts for the first time. It was redescribed and figured.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.451-454
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• 2008

Potential tsunamis which may occur near Ryukyu Islands were simulated. Propagation characteristics of the potential tsunamis over the southwestern sea and the influence of tsunamis on the southwestern coast of Korean Peninsula were analyzed. The shallow water area in the east sea of China and the deep water Okinawa Trough play an important role in wave transformation and propagation of the potential tsunamis. The propagation characteristics of the potential tsunamis generated near Ryukyu Islands can be described as in followings : In the first stage after generation, the tsunamis propagate with high speed both northeastward and southwestward along the Okinawa Trough. As a result the waves are elongated and the tsunami height is significantly reduced. The elongated crest of tsunamis spans the whole distance of the Okinawa Trough and lines up toward the edge of the continental shelf of East China Sea. Then, the tsunamis are propagating towards the southeast coast of China. Thus, the influence of tsunamis on the Korean coasts becomes weak.

• 한국해양학회지
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• v.29 no.1
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• pp.28-41
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• 1994

The hourly sea level data are analyzed in order to find the general characteristics of the storm surges at the coasts of Korea, Japan and Russia. the surges are calculated by removing the predicted tides from the observed sea level at 44 tidal stations. In korea, positive and negative surges of the west coast are larger than those of the south and east coasts. The magnitudes of negative surges are larger than those of positive surges at the west of Japan. The surges of the northern Russian coast are relatively larger than those of the southern west coast of japan. The yearly maximum positive surges at the west coast of Korea, are found to be caused by extratropical storm, but the maximum positive surges at the south or the east coast of Korea are due to the summer typhoon. Mostly the yearly maximum negative surges occur at the west coast of Korea (particularly Inchon), and they are caused by extratropical storm.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.6
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• pp.561-569
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• 2013

EOF analysis of tidal residual derived from 2003~2009 tide data was used to identify the spatio-temporal variability. The effect of sea surface air pressures and winds on the tidal residual was also investigated by the correlation analysis. The first mode accounting for 68 % of the total variance represented concurrent sea level rise or fall, and the second mode accounting for 21 % of the total variance explained alternative sea level rise and fall between West Sea coast and both South Sea and East Sea coasts. While northerly and southerly winds dominated the tidal residual in the eastern coast of Yellow Sea, the effect of sea surface air pressures on the tidal residual increased along the coastal regions from South Sea to East Sea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.3
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• pp.306-316
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• 2003

We conducted a time-series analysis of temperature and salinity of sea water around Jeju Island, Korea. Monthly mean temperature and salinity was influenced by precipitation and weather conditions on Jeju as well as by oceanographic conditions of the open sea such as the Tsushima Warm Current and sea water in coastal areas. Salinity of Jeju coastal waters was the highest in April, and it was always over 34.00 psu with tiny fluctuation between December and June. Due to the effects of the Tsushima Warm Current, Jeju coastal waters maintained high salinity and stability. Low salinity and its large fluctuations during summer were closely associated with the China Coastal Water and precipitation in Jeju. The place of the lowest water temperature was the northeast coasts of Jeju (Gimneong, Hado, Jongdalri). In winter, as warmer water of the Tsushima Warm Current appeared in western area of Jeju dwindled flowing along the northern coasts of Jeju area and becoming cool, the lowest water temperature often appeared locally in Gimnyeong and its vicinitly in summer. The Tsushima Warm Current flows into the east entrance of Jeju Strait, but its influence is weak because of geometry and strong vertical mixing due to fast tidal currents.

• Journal of Aquaculture
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• v.20 no.2
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• pp.81-84
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• 2007

We studied two research items that can be undetermined issues in the artificial seed production of the Japanese scallops, Patinopecten yessoensis, batch-specific quality of the reproductive outputs and nursery acclimation, in the embayed waters of Yangyang, Gangwon, Korea. The first batch of the spawner showed better results in terms of survival, growth, and resistance against parasitic ciliate infection over the second batch that was obtained in 5 days after first batch from the same spawner. The early attached spats directly placed in the farming ground (the unacclimated) were resistant against the water current of the open environment, by showing survival of about 80% for a month, a normal survival compared with other results. However, the spat survival during the nursery acclimation was significantly lowered in comparison with that in the unacclimated condition (P<0.01). We discussed the research results of the two items, particularly focusing on their availability for mass seed production for aquaculture in the Korean coastal waters of the East Sea (Sea of Japan).

• Ocean and Polar Research
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• v.42 no.3
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• pp.263-270
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• 2020

The distribution and genotypes of the sea nettle Chrysaora pacifica have been reported in the South Sea of Korea; however, little research work has been attempted in the East Sea. Here, we collected similar jellyfishes from the East Sea coasts (Goseong, Yangyang and Sokcho), and identified them to the sea nettle morphologically. In addition, the genotypes of these sea nettle were compared with those from the South Sea (Tongyeong and Geoje). Phylogenetic analysis by using the mitochondrial COI sequences showed that the genus Chrysaora was clearly separated from other taxa to be formed a monophyletic group, with each species distinctly separated. C. pacifica in the East and South Seas was separated geographically by the COI phylogeography, representing potentially different populations. The COI gene of the Korean C. pacifica had approximately 7 times more genetic variation than the nuclear ITS rDNA, and thus it might be considered as a useful marker for genetic analysis of the jellyfish population.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.10a
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• pp.290-294
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• 2001

Satellite data, with Sea Surface Temperature(SST) by NOAA and Sea Level(SL) by Topex/poseidon, are used to estimate characteristics on the variations and correlations of SST and SL in the East Asian Seas from January 1993 through May 1998. In the oceanic climate, the variations of SL shown the high values in the main current of Kuroshio and the variations of SST shown not the remarkable seasonal variations because of the continuos compensation of warm current by Kuroshio. In the continental climate, SL shown high variations in the estuaries(the Yellow River, the Yangtze River) with the mixing the fresh water in the mouth of estuaries of the saline water in the coasts of continent and SST shown highly the seasonal variations due to the climatic effect of continents. In the steric variations in summer, the eastern sea of Japan, the East China Sea and the western sea of Korea shown the increment of sea level with 10~20cm. But the Bohai bay in China shown relatively the high values of 20~30cm due to the continental climate. Generally the trends of SST and SL increased during all periods. That is say, the slopes of SST and SL presented 0.29$^{\circ}C$/year and 0.84cm/year, respectively. The annual and semi-annual amplitudes shown a remarkable variations in the western sea of Korea and the eastern sea of Japan.

• Korean Journal of Environmental Biology
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• v.40 no.4
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• pp.477-496
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• 2022

During a survey of free-living marine nematodes of Korea, two new marine desmoscolecid nematodes belonging to subgenus Quadricoma Filipjev, 1922 were discovered. Tricoma (Q.) jejuensis sp. nov. and T.(Q.) unipapillata sp. nov. are described based on specimens obtained from washings of coarse sediments from eastern and southern coasts of Korea. Tricoma (Q.) jejuensis sp. nov. is characterized by having 33 quadricomoid body rings and inversion at main ring 23, pentagonal head with truncated anterior end, a pair of ocelli situated at main ring 6, somatic setae comprising of 8 pairs of subdorsal setae and 12 pairs of subventral setae, and relatively short spicules (42-46 ㎛ long). Tricoma (Q.) unipapillata sp. nov. is characterized by 44 quadricomoid body rings and inversion at main ring 32, somatic setae comprising of 7 pairs of subdorsal setae and 10 pairs of subventral setae, globular head truncated anterior end, relatively short and stumpy cephalic setae with cuticular flange, one single naked ventral median genital papillae situated on main ring 20, and spicules with a proximally marked capitulum. Detailed morphological descriptions and illustrations of these two new species are provided in this study.