• Title/Summary/Keyword: Yellow sea

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STUDIES ON THE FREEZING OF YELLOW SEA BREAM (옥돔의 동결에 관한 연구 2. 동결에 의한 옥돔조직의 변화)

  • SONG Dae-Jin;KANG Yeung-Joo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.12 no.3
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    • pp.131-136
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    • 1979
  • Histological changes of yellow sea bream, Branchiostegus japonicus japonicus, were observed under microscope during freezing storage for 6 months at $65^{\circ}C$ and $-35^{\circ}C$, and the results were compared with the muscle structure of fresh muscle. The freezing storage of yellow sea bream at $-^{\circ}C$ showed more changes in muscle structure than that stored at $-35^{\circ}C$. In the view point of the changes of the muscle structure, the yellow sea bream can be stored up to 1 month at $65^{\circ}C$ and 3 months at $-35^{\circ}C$. The freezing of yellow sea bream at $-5^{\circ}C$ showed higher extracellular freezing than that at $-35^{\circ}C$.

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The Seasonal Environmental Factors Affecting Copepod Community in the Anma Islands of Yeonggwang, Yellow Sea (황해 영광 안마 군도 해역의 요각류 출현 양상에 영향을 미치는 계절적 환경 요인)

  • Young Seok Jeong;Seok Ju Lee;Seohwi Choo;Yang-Ho Yoon;Hyeonseo Cho;Dae-Jin Kim;Ho Young Soh
    • Ocean and Polar Research
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    • v.45 no.2
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    • pp.43-55
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    • 2023
  • This study was conducted to understand the seasonal patterns and variation of the copepod community in the Anma Islands of Yeonggwang, Yellow Sea, with a focus on seasonal surveys to assess the factors affecting their occurrence. Throughout the survey period, Acartia hongi, Paracalanus parvus s. l., and Ditrichocorycaeus affinis were dominant species, while Acartia ohtsukai, Acartia pacifica, Bestiolina coreana, Centropages abdominalis, Labidocera rotunda, Paracalanus sp., Tortanus derjugini, Tortanus forcipatus occurred differently by season and station. As a results of cluster analysis, the copepod communities were distinguished into three distinct groups: spring-winter, summer, and autumn. The results of this study showed that the occurrence patterns of copepod species can vary depending on environmental conditions (topographic, distance from the inshore, etc.), and their spatial occurrence patterns between seasons were controlled by water temperature and prey conditions. One of the physical mechanisms that can affect the distribution of zooplankton in the Yellow Sea is the behavior of the Yellow Sea Bottom Cold Water (YSBCW), which shows remarkable seasonal fluctuations. More detailed further studies are needed for clear grounds for mainly why to many Calanus sinicus in the central region of the Yellow Sea are seasonally moving to the inshore, what strategies to seasonally maintain the population, and support the possibilities of complex factors.

Distribution of DMS Concenturation in the Atmosphere over Yellow Sea - Preliminary Measurements 1mm Duk-Juk Island (한국 황해지역의 DMS 분포특성에 대한 연구 - 덕적도를 중심으로)

  • Kim, Ki-Hyun;Kim, Ji-Young;Song, Ki-Bum;Kim, Na-Young;Lee, Gang-Woong;Bae, Gwi-Nam
    • Journal of the Korean earth science society
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    • v.21 no.1
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    • pp.51-58
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    • 2000
  • This study was performed to accumulate database for natural sulfur emissions in the Yellow Sea region of Korea. The atmospheric concentrations of dimethylsulfide(DMS) were measured during two intensive field experiments (April and September 1999) from Duk-Juk Island located in the Yellow Sea. Ship-measurement of DMS was made additionally between Chungdo(China) and Inchun(Korea) across the Yellow Sea during June 1999. The mean(and ISD) of DMS concentrations in Duk-Juk Island during two field campaigns was $24.0{\pm}40.5$(n=40, April) and $61.1{\pm}37.9$ pptv(n=35, September), respectively. The atmospheric DMS measured from ship experiments was generally low and close to the background concentrations in the open sea area. The temporal distributions of DMS concentration were complicated in some sense but comparable to those of ambient meteorological parameters. On the basis of our measurements of atmospheric DMS(and evidence found from previous studies), the sea-to-air flux of DMS in the Yellow Sea is estimated to be about 4Gg S/yr. This amount of natural S emissions is relatively lower than the estimates derived for Cheju Island. Therefore, additional experiments may be desperate to derive more reliable figures for natural sulfur emissions in the Yellow Sea region.

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Studies on the Fishery Biology of Pomfrets, Pampus spp. in the Korean Waters 5. Distribution and Fishing Condition (한국근해 병어류의 자원생물학적 연구 5. 분포와 어황)

  • CHO Kyu Dae;KIM Jeong Chang;CHOE Yong Kyu
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.22 no.5
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    • pp.294-305
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    • 1989
  • Basedon statistical data of pomfret (Pampus spp.) catches by the stow net during $1970\~1985$, the distribution and migration of pomfrets and fishing conditions were investigated in relation to oceanographic conditions, in the East China Sea and the Yellow Sea. The main fishing grounds of Pomfrets were formed around the Great Yangtze Sand Bank which locates between the Cheju Island and the mouth of the Yangtze River. Its area occupied only 11 percent of all fishing grounds, and about 70 percent of total catch was found there. The coefficient of variation(CV) in catch was below 0.01 in the whole fishing grounds and that of tile main fishing grounds (14 fishing areas) was $0.001\~0.003$. This area was indicated markedly by the inflow of Yellow Sea Warm Current from spring to autumn, and this mixing area which formed the oceanic front among the China Continental Shelf Water, the Yellow Sea Bottom Cold Water and the Tsushima Warm Current. The pomfrets migrates to south-north according to the expansion and contraction of the Tsushima Warm Current including the Yellow Sea Warm Current and the Yellow Sea Bottom Cold Water. Therefore, it migrates to north of the Yellow Sea in summer and to southern part of the East China Sea in winter. The most frequent range of the water type for high catch was $10\~12^{\circ}C$ in temperature and $32.4\~33.4\%_{circ}$ in salinity. The ranges was occupied more than 70 percent of total catch on fishing season. The frequency range of the water type was not different between the abundant fishing periods and the poor fishing periods in terms of the maximum catches.

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On the Wintertime Wind-driven Circulation in the Yellow Sea and the East China Sea : Part I. Effect of Tide-induced Bottom Friction (황해.동중국해의 겨울철 취송 순환에 대하여: Part I. 조류에 의한 저면 마찰력의 영향)

  • Lee, Jong-Chan;Kim, Chang-Shik;Jung, Kyung-Tae;Jun, Ki-Cheon
    • Ocean and Polar Research
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    • v.25 no.spc3
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    • pp.361-371
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    • 2003
  • The effect of bottom friction on the steady wind-driven circulation in the Yellow Sea and the East China Sea (YSECS) has been studied using a two-dimensional numerical model with and without tidal forcing. Upwind flow experiment in YSECS has also been carried out with a schematic time variation in the wind field. The surface water setup and circulation pattern due to steady wind forcing are found to be very sensitive to the bottom friction. When the effects of tidal currents are neglected, the overall current velocities are overestimated and eddies of various sizes appear, upwind flow is formed within the deep trough of the Yellow Sea, forming a part of the topographic gyre on the side of Korea. When tidal forcing is taken into account, the wind-induced surface elevations are smoothed out due to the strong tide-induced bottom friction, which is aligned almost normal to the wind stresses; weak upwind flow is farmed in the deep trough of the Yellow Sea, west and south of Jeju. Calculation with wind forcing only through a parameterized linear bottom friction produces almost same results from the calculation with $M_2$ tidal forcing and wind forcing using a quadratic bottom friction, supporting Hunter (1975)'s linearization of bottom friction which includes the effect of tidal current, can be applied to the simulation of wind-driven circulation in YSECS. The results show that steady wind forcing is not a dominant factor to the winter-time upwind flow in YSECS. Upwind flow experiment which considers the relaxation of pressure gradient (Huesh et al. 1986) shows that 1) a downwind flow is dominant over the whole YSECS when the northerly wind reaches a maximum speed; 2) a trend of upwind flow near the trough is found during relaxation when the wind abates; 3) a northward flow dominates over the YSECS after the wind stops. The results also show that the upwind flow in the trough of Yellow Sea is forced by a wind-induced longitudinal surface elevation gradient.

The study on efficient transport system in Circle Yellow-Sea region using rail & sea multi transport system (철도-해운 복합운송 시스템을 이용한 환황해권 수송 효율화 연구)

  • Han, Ji-Young;Yoo, Jae-Kyun;Lee, Yoon-Mi
    • Proceedings of the KSR Conference
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    • 2010.06a
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    • pp.389-396
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    • 2010
  • After analyzing network of the region of western sea, which is the center of Circle Yellow-Sea economic region, and Circle Bo-Hai and the delta of a long river economic region, which are belong to three major economic region of China, as an efficient strategy, rail & sea multi-transport system of Korea-China joint SOC strategy is suggested. Rail & Sea multi-transport system, which is the links of railroads and shipping transport, can be subdivided into train-ferry, which is the transport of loaded trains into a vessel, and transshipment, which is transshipment of containers from railroads to vessels. And, the way of railroads transport through a tunnel under the sea is also suggested.

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Temperature Variabilities at Upper Layer in the Korean Marine Waters Related to Climate Regime Shifts in the North Pacific (한국주변해역 상층부의 수온 변동과 북태평양 기후체제와의 관계)

  • Rahman, SM M.;Lee, Chung Il
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.22 no.1
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    • pp.145-151
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    • 2016
  • Temperature variability at the upper layer related to climate regime shifts in the Korean waters was illustrated using water temperature, climate index. Three major climate regime shifts (CRS) in 1976, 1988 and 1998 in north Pacific region had an significant influence on the major marine ecosystems structure pattern. Three marginal seas around Korean peninsula; East Sea, East China Sea and Yellow Sea also got important impact from this kind of decadal shift. We used 10m sea water temperatures in four regions of Korean waters since 1950 to detect major fluctuation patterns both seasonally and also decadal shift. 1988 CRS was occurred in all of the study areas in most seasons however, 1998 CRS was only detected in the Yellow Sea and in the southern part of the East Sea. 1976 CRS was detected in all of the study area mainly in winter. After 1998 CRS, the water temperature in the southern part of the East Sea, East China Sea and Yellow Sea were going into decreased pattern; however, in the northern part of the East Sea, it was further shifted to increasing pattern which was started from 1988 CRS period.

The Yellow Sea Ecoregion Conservation Project : the Present Situation and its Implications (황해생태지역 보전사업 추진현황 및 시사점)

  • Kim, Gwang Tae;Choi, Young Rae;Jang, Ji Young;Kim, Woong-Seo
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.15 no.4
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    • pp.337-348
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    • 2012
  • The Yellow Sea Ecoregion Conservation Project is a joint international project which is carried out under the purposes of conserving the habitats in the Yellow Sea Ecoregion and biodiversity from various threats that damage ecosystems, informing the importance and value of the Yellow Sea Ecoregion, and promoting the understanding and interests of Korea, China and Japan. Subsequent to the Yellow Sea Ecoregion Planning Programme which had been performed during the period from 2002 to 2006, the Yellow Sea Ecoregion Support Project has been performed over 7 years in total from 2007 to 2014. Panasonic is sponsoring the financing of the project, and the organizations in charge of the project by country are Korea Institute of Ocean Science & Technology for Korea and World Wide Fund for Nature branches for China and Japan. While the Yellow Sea Ecoregion Planning Programme was focused on the biological assessment and the selection of potential priority area by scientific review, the Yellow Sea Ecoregion Support Project is oriented toward practical activities targeting more diversified stakeholder. Especially, this project plans to support direct conservation activities in the region and participation and cooperation from local residents. The project plan is comprised of 3 phases. During the first period from 2008 to 2009, small grant projects were operated targeting 16 institutions of Korea and China, and for the second period from 2010 to 2012, one place each was selected as demonstration site for habitat conservation in Korea and China respectively and supported for three years to introduce the conservation method based on international standards such as the management of marine protected areas, ecosystem-based management and community-based management and simultaneously to develop habitat conservation activities suitable for national and regional characteristics. During the period from 2013 to 2014 which is the last phase, the project plans to distribute the performance of small grant projects and demonstration site activities through a series of forums among stakeholder. Through the activities described above, the recognition of general public on the conservation of the Yellow Sea Ecoregion was changed positively, and community-based management began to be reflected in the policies for the marine protected areas of central and local government.

The Effect of Yellow Soil on Mortality of Korean Scallops, Patinopecten yessoensis at Indoor Tank

  • Oh, Bong-Se;Jung, Choon-Koo;Kwon, Mun-Gyeong;Lee, Jung-Sick
    • The Korean Journal of Malacology
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    • v.26 no.3
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    • pp.179-183
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    • 2010
  • In other to understand the effect of yellow soil to mortality of Korean scallops, P. yessoensis, We investigated its mortality at indoor tanks. The environmental conditions such as water temperature, Salinity, Do and pH were continued constantly during the experimental periods. The 100% of survival rate showed in two experiments groups such as 0.1% and 0.4% of concentration of yellow soil and the other groups as 0.05% and 0.2% of concentration of yellow soil was appeared one dead scallop at each group for 8 days of the experiment periods. the gills of scallop in high concentration of yellow soil (0.2% and 0.4% groups) were covered by yellow soil particles so that this group's scallop should be got a high stress from yellow soil. I think this situation will be more continued for long time the scallop will become to dead. The results of bacteriological analysis did not isolated from haemolymph of scallops and no Perkinsus infectious disease in scallops and the scallops showed necrosis and degeneration on digestive grand and gills of scallop.

Geographical Distribution and Catch Fluctuations of Mottled Skate, Beringraja pulchra in the Eastern Yellow Sea (황해 동부해역 참홍어의 지리적 분포특성과 어획량 변동)

  • Jang, Myunghun;Jo, Hyun-Soo;Kweon, Dae-Hyun;Cha, Byung-Yul;Hwang, Jahye;Han, Kyung-Nam;Im, Yang-Jae
    • Korean Journal of Ichthyology
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    • v.26 no.4
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    • pp.295-302
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    • 2014
  • Mottled skates, Beringraja pulchra, mainly found in the Yellow Sea were caught by otter trawl at 30 stations from 2002 to 2013 to identify the distribution patterns and ecology of the fish in the eastern Yellow Sea. A total of 442 individuals of mottled skate were caught at the 112 hauls of the total 892 hauls. The fish was widely distributed in the entire survey area in spring and autumn, and mainly caught in the northern offshore in summer and in the southern part in winter. The under-yearlings of the mottled skate were mainly caught in the offshore in spring and autumn. The mottled skates were found at the temperature ranges of $3.8{\sim}14.5^{\circ}C$, and the salinity of 31.2~34.2. The catch data of the fish suggested that water temperature be a critical factor for the distribution with the optimal ranges of $5{\sim}14^{\circ}C$. Salinity and water depth were not critical as much as the water temperature for the distribution of the mottled skates in the Yellow Sea. Also, the annual fluctuations of the fish catch were reviewed using the catch data from korea fisheries cooperative and national statistics from 1991 to 2009.