• Title/Summary/Keyword: West Sea

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Nomenclature of the Seas Around the Korean Peninsula Derived From Analyses of Papers in Two Representative Korean Ocean and Fisheries Science Journals: Present Status and Future (국내 대표 해양·수산 과학논문 분석을 통한 우리나라 주변 바다 이름표기에 대한 제언)

  • BYUN, DO-SEONG;CHOI, BYOUNG-JU
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.23 no.3
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    • pp.125-151
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    • 2018
  • We grouped the names attributed to the seas surrounding the Korean Peninsula in maps published in two major Korean ocean and fisheries science journals over the period from 1998 to 2017: the Journal of the Korean Society of Oceanography (The Sea) and the Korean Journal of Fisheries and Aquatic Science (KFAS). The names attributed to these seas in maps of journal paper broadly were classified into three groupings: (1) East Sea and Yellow Sea; (2) East Sea, Yellow Sea, and South Sea; or (3) East Sea, West Sea and South Sea. The name 'East Sea' was dominantly used for the waters between Korea and Japan. In contrast, the water between Korea and China has been mostly labelled as 'Yellow Sea' but sometimes labelled as 'West Sea'. The waters between the south coast of Korea and Kyushu, Japan were labelled as either 'Korea Strait' or 'South Sea'. This analysis on sea names in the maps of 'The Sea' and 'KFAS' reveals that domestic researchers frequently mix geographical and international names when referring to the waters surrounding the Korean Peninsula. These inconsistencies provide the motivation for the development of a basic unifying guideline for naming the seas surrounding the Korean Peninsula. With respect to this, we recommend the use of separate names for the marginal seas between continental landmasses and/or islands versus for the coastal waters surrounding Korea. For the marginal seas, the internationally recognized names are recommended to be used: East Sea; Yellow Sea; Korea Strait; and East China Sea. While for coastal seas, including Korea's territorial sea, the following geographical nomenclature is suggested to differentiate them from the marginal sea names: Coastal Sea off the East Coast of Korea (or the East Korea Coastal Zone), Coastal Sea off the South Coast of Korea (or the South Coastal Zone of Korea), and Coastal Sea off the West Coast of Korea (or the West Korea Coastal Zone). Further, for small or specific study areas, the local region names, district names, the sea names and the undersea feature names can be used on the maps.

Spatiotemporal Distribution of Pacific Anchovy (Engraulis japonicus) Eggs in the West Sea of Korea

  • Hwang, Sun-Do;McFarlane, Gordon A.;Choi, Ok-In;Kim, Jong-Sik;Hwang, Hak-Jin
    • Fisheries and Aquatic Sciences
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    • v.10 no.2
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    • pp.74-85
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    • 2007
  • Pacific anchovy (Engraulis japonicus) eggs were collected during the spawning season (2000-2003) using a revised ring net in the coastal waters adjacent to the Geum River Estuary in the West Sea of Korea (Yellow Sea). Anchovy eggs were present from May to September, showing a peak in spawning from June to July when the water temperature and salinity were $17-27^{\circ}C$ and above 30.00 psu, respectively. During the main spawning season, no clear diel cycle (regarding the 24-h sampling period of dusk, night, dawn, and daytime) was detected in the vertical distribution of anchovy eggs near Eocheong Island (50-60m depth). Judging from the developmental stages of the collected eggs, it appeared that anchovies spawned mostly at night and that the eggs hatched at dusk and during the night. The density of anchovy eggs was high in the southwest-northeast direction in June, and spawners appeared to move offshore in July. Mean egg density was higher in June 2002 than in June 2003 when water temperatures and salinities were lower. This study on the spatiotemporal distribution of eggs will contribute to developing management plans for the Pacific anchovy in Korea.

Toxicity Assessment of Ocean Dumping Wastes Using Fertilization and Embryo Development Rates in the Sea Urchin (Strongylocentrotus nudus) (둥근성게(Strongylocentrotus nudus)의 수정 및 배 발생률을 이용한 해양배출 폐기물의 독성평가)

  • Hwang, Un-Ki;Rhee, Choong-Won;Kim, Kwang-Seop;Kim, Hyoung-Choul;An, Kyoung-Ho;Park, Seung-Youn
    • Environmental Analysis Health and Toxicology
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    • v.24 no.1
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    • pp.25-32
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    • 2009
  • Toxicity of ocean dumping wastes(dye waste, urban sewage, food waste) were examined by observing fertilization and embryo development rates of the Sea Urchin, Strongylocentrotus nudus. Spawning was induced by injecting 1 mL of 0.5 M KCl into coelomic cavity. Males released white or cream-colored sperms and females released yellow or orange-colored eggs. Experiments were began within 30 min after the collection of both gametes. The fertilization and embryo development rates tests were performed for 10 min and 48 h after fertilization, respectively. The fertilization and embryo development rates in the control condition(not including ocean dumping wastes sludge elutriate) were greater than 90%, but markedly decreased with increasing concentrations of ocean dumping waste sludge elutriate. The fertilization and normal embryogenesis rates were significantly inhibited in all waste sludge elutriate from dye waste($EC_{50}$=5.76; $EC_{50}$=4.53), urban sewage($EC_{50}$=9.82; $EC_{50}$=9.67) and food waste($EC_{50}$=3.90; $EC_{50}$=3.27), respectively. The NOEC(>3.13%) and LOEC(3.13%) of fertiliztion and normal embryogenesis rates very similar in all waste sludge elutriate. These results suggest biological assay using the fertilization and embryo development rates of S. nudus are very useful test method for the ecological toxicity assessment of ocean dumping wastes.

Northern Limit Line and its Problems of the Law of the Sea in the Sea Area around Five South Korean Islands of the West Sea (북방한계선(北方限界線)과 서해5도(西海5島) 주변수역(周邊水域)의 해양법문제(海洋法問題))

  • CHOl, Jong-Hwa;KIM, Young-Gyu
    • Journal of Fisheries and Marine Sciences Education
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    • v.16 no.1
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    • pp.110-123
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    • 2004
  • Five Islands in the West Sea of Korea (Baekryeong-do, Daecheong-do, Socheong-do, Yeonpyeong-do, and Woo-do) are located very close to the North Korea's coast and all of them are under the jurisdiction of South Korea. The North and South Korean naval vessels clashed twice in the West Sea of Korea on June 15, 1999 and on June 29, 2002. These incidents were resulted from conflicts over the validity of the Northern Limit Line(NLL) and the appropriate maritime boundary between the two Koreas. From the viewpoint of South Korea, the North Limit Line is a lawful Maritime Military Demarcation Line under the Korean Military Armistice Agreement and it must be maintained as a maritime boundary between two Koreas until being substituted by a peace treaty. In conclusion, the maritime boundary between two Koreas cannot be settled easily by the principles of the International Law of the Sea at present.

Distribution of ichthyoplankton in the West coastal waters of Korea (서해연안 해역에 분포하는 부유성 난 및 자치어의 분포특성)

  • YOUN, Byoung-Il;LEE, Seung-Jong;SOHN, Myoung-Ho;HAN, Song-hun;LEE, Hyung-been;KIM, Maeng-jin;HAN, Kyung-Ho
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.55 no.3
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    • pp.243-251
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    • 2019
  • The ichthyoplanktons were sampled by Bongo net to study the distribution of the eggs and larvae in the West coastal waters of Korea during the study period (February, May, August and October of 2017). Collected fish eggs were divided into Engraulis japonicus and unidentified species. The most dominant species, Engraulis japonicus accounted for 79.52% of the total fish egg, which was followed by unidentified species (20.48%). The total of 36 taxa in fish larvae were identified based on morphological and molecular characteristics. Fish larvae were dominant by Gobiidae species. 48.30% of the total catch in abundance, which was followed by Engraulis japonicus (31.86%). These two taxa composed 80.16% of the total collected fish larvae. The seasonal diversity index of species from the collected fish larvae in the West coastal waters in 2017 was 0.625-1.883 and the evenness index was 0.380-0.865. In addition, dominance index was 0.618-0.920 and richness was 0.573-3.189.

Distribution and Occurrence of Swimming Crab, Portunus trituberculatus Larvae in the Mid-western Coast of Korea in the Yellow Sea (우리나라 서해중부 연안의 산란철 꽃게유생 분포 및 출현량)

  • Jo, Hyun-Su;Park, Won-Gyu;Kwon, Dae-Hyeon;Cha, Byung-Yeul;Im, Yang-Jae
    • Journal of Fisheries and Marine Sciences Education
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    • v.25 no.4
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    • pp.991-997
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    • 2013
  • Distribution and occurrence of swimming crab, Portunus trituberculatus larvae were investigated in the mid-western coast of Korea in the Yellow Sea. P. trituberculatus larvae were collected in July and August from 2010 to 2012. Bongo net with 303 mesh was deployed once with a double oblique tow. Zoea I (ZI) densities were highest in all sampling months. Then densities of later larval stages decreased dramatically. In general, larval densities at the stations in northern parts and coastal areas were higher than those at the southern and offshore area. Because egg bearing seasons of P. trituberculatus in the study area are between April and August, larval densities, particularly, of ZI may be underestimated. Considering higher densities of ZI and lower ones of later stages, larvae may be transported to growing area and returned to the parental populations. Larval densities and sea surface temperature were not correlated.

Monthly Variation of Phytoplankton Composition and Water quality in Cupped Oyster Crassostrea gigas Culture Area in Iwon, Korea (이원면 굴, Crassostrea gigas 양식어장의 월별 식물플랑크톤 종조성 및 수질환경 변화)

  • Kim, Su Kyoung;Kim, Byeong Ho;Oh, Eun Kyoung;Song, Gi Chul;Park, Soung Yun;Hahn, Ki Yeon;Lim, Hyun Jeong
    • The Korean Journal of Malacology
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    • v.30 no.3
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    • pp.249-258
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    • 2014
  • Phytoplankton species composition and ecological index (diversity, evenness, richness and dominance) were analysed from April 2013 to March 2014 at 10 stations of cupped oyster, Crassostrea gigas culture area in Iwon coast, Korea. Seasonal and positional variation of phytoplankton standing crops, biomass, dominant species and water quality were distinctively different according to occasionally inflow of Iwon dam reservoired water. The composition of phytoplankton species were Bacillariophyceae 98, Dinophycease 22, Chlorophycease 13, Cyanophyceae 8, Silicofalgellate 4, Euglenophyceae 2, Cryptophyceae 1 species. The most dominant species was Bacillariophyceae as 64.0%. The highest biomass of phytoplankton recorded in September as $40,910{\times}10^3$ cell/L at the station 1, near from inland water inflow area. Ecological indices (diversity, richness, evenness, and dominance index), used for structural change of phytoplankton community and water quality (temperature, dissolved oxygen, salinity) showed difference of spatiotemporal property also.

Comparison of maturation and secondary spawning of fleshy shrimp Penaeus chinensis fed different kinds of diets

  • Youngguk Jin;Yu-Hyeon Jeon;Sukyoung Kim;Eunha Jeong;Su-Kyoung Kim
    • Fisheries and Aquatic Sciences
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    • v.25 no.12
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    • pp.619-625
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    • 2022
  • The study carried out a 15-day feeding trial of the fleshy shrimp broodstock that have just finished their first spawn using five different maturation feed types (three types of manufactured feed, fresh feed, and commercial feed) to induce multiple spawning in the shrimp and then analyzed and compared hemolymph levels of total protein, total lipid, hemocyanin, glucose, and cholesterol as well as ovary histology between the treatments to identify the potential of the experimental diets to be utilized as maturation feed. The study found that the manufactured diets of polychaetes + clam and polychaetes + clam + squid resulted in significantly higher levels of lipid and protein in shrimp hemolymph suggesting an indicator of multiple spawning in the fleshy shrimp. The other manufactured diet of polychaets + squid led to the highest 2nd spawning with significantly lower levels of lipid, protein, and cholesterol in shrimp hemolymph. The fresh feed treatment showed similar hematological as well as histological responses to the manufactured diet of polychaetes + squid, but with a significantly lower spawning volume compared to the other treatments. The study demonstrated that the manufactured diets could replace fresh feed as maturation feed and attain a higher shrimp maturation than the commercial feed.