• 수산해양기술연구
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• 제44권2호
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• pp.112-119
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• 2008

The fundamental data on the catch fluctuation in the rectangular set net according to the tide age were developed based on the catches recorded from the year 1986 to 2004 in the coastal waters of Hamdeok, Jeju. Total catch by the rectangular set net had a deep connection with the tide age. In particular, during increasing tide, total catch were reduced gradually from the neap tide to the high tide. As it turned out, the slope of total catch declined by degree and showed a correlation coefficient of determination of 0.76. On the contrary, in the case of decreasing tide, there was little sign of rise in total catch. In particular, large catch seemed to occur at the next tide to the neap tide. In the relation between the catch and the tide age, the level of the correlation coefficient chosen at $p{\leq}0.05$ decreased in the order rabbitfish(-0.84) and horse mackerel(-0.71), while the significance of other dominant species were not selected.

• Journal of the korean society of oceanography
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• 제35권4호
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• pp.161-169
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• 2000

A seasonal circulation in the East China Sea and the Yellow Sea and its possible cause have been studied with CSK data during 1965-1989. Water mass distributions are clear in winter, but not in summer because the upper layer waters are quite influenced by atmosphere. To solve the problem, a water mass analysis by mixing ratio is used for the lower layer waters. The results show that the distribution of Tsushima Warm Current Water expands to the Yellow Sea in winter and retreats to the East China Sea in summer. It means that there is a very slow seasonal circulation between the East China Sea and the Yellow Sea: Tsushima Warm Current Water flows into the Yellow Sea in winter and coastal water flows out of the Yellow Sea in summer. By the circulation, the front between Tsushima Warm Current Water and coastal water moves toward the shelf break in summer so that the flow is faster in the deeper region. The process eventually makes the transport in the Korea Strait increase. The Kuroshio does not seem to influence the process. A possible mechanism of the process is the seasonal change of sea surface slope due to different local effects of surface heating and diluting between the East China Sea and the Yellow Sea.

• 수산해양기술연구
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• 제51권2호
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• pp.265-271
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• 2015

The feeding habits of Okamejei kenojei were studied using 242 specimens collected from October 2010 to September 2011 in the coastal waters of Gadeok-do, Korea. O. kenojei was carnivorous feeder that consumed mainly shrimps, crabs, and fishes. Its diet also included small quantities of stomatods, cephalopods, amphipods. The size of O. kenojei ranged from 10.4 to 47.4 cm in total length (TL). O. kenojei showed ontogenetic dietary shift. <15.0, 15.0-19.9 cm size classes fed mainly on shrimps and amphipods. 20.0-24.9 cm size class fed mainly shrimps and crabs. Thereafter, shrimps and crabs were decreased with ontogenesis while fishes and cephalopods were increased. Increasing size, the mN/ST were constantly decreased, but mW/ST were constantly increased.

• 수산해양기술연구
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• 제55권4호
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• pp.320-326
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• 2019

The diet composition of Arctoscopus japonicus was studied using 448 specimens collected in the coastal waters of East Sea, Korea. The size of the specimens ranged from 6.2-25.3 cm in total length (TL). A. japonicus were fed mainly on amphipods that constituted 76.1% in IRI. Euphausiids were the second largest prey component. The diets also include small quantities of crabs, copepods, mysids, cephalopods, monogeneans, and fishes. A. japonicus showed ontogenetic changes in feeding habits. Smaller individuals (6-10 cm, TL) fed mainly on amphipods. The proportion of amphipods decreased as body size increased, whereas the consumption of euphausiids gradually increased (10-14 cm, TL). As the body size more increased, the proportion of amphipods increased whereas euphausiids decreased (14-26 cm, TL).

• 수산해양기술연구
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• 제55권4호
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• pp.349-355
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• 2019

Reproductive ecology of rabbit fish, Siganus fuscescens were investigated from samples collected monthly in the coastal waters off Jeju Island of Korea from February to December 2014. In male and female of S. fuscescens, the values of GSI were reached high values between July to August in which the water temperature was high, and then decreased until December. The occurrence of individuals which have mature eggs in ovary were higher from July to August. Therefore, a main spawning season was estimated from July to August, with the highest peak in July. Throughout histological observation of the ovary in the spawning period, S. fuscescens belong to an group-synchronous and has a one spawning season a year. Fecundity of ovary ranged from 380,000 to 2,600,000 during the spawning period. Size at 50% sexual maturity, determined from logistic equation, were 25.1 cm TL which is over two years.

• 환경생물
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• 제17권3호
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• pp.217-232
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• 1999

본 종설은 우리나라에서 발생하고 있는 적조현상을 정리하여 적조의 정의, 명칭, 년도별 연구상황, 적조발생 원인 및 생물, 독성, 인명 및 수산물의 피해, 피해저감 및 방제기술에 대하여 소개하였다. 우리나라의 초기의 적조는 돌말류에 의해 발생되었으나, 해양오염이 심각한 1970년대 말부터 무독성 와편 모조류에 의해 그리고 1980년대 말에는 유독성 편모조류에 의해 발생되고 있다. 적조발생 규모는 초기에는 국지적이었으나 근래에는 광역화이기 때문에 수산업에 막대한 지장을 초래하고 있다. 따라서 적조에 따른 피해저감 및 방제대책의 연구가 절실히 요구된다.

• 수산해양기술연구
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• 제43권4호
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• pp.261-273
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• 2007

To analyze quantitative fluctuation in abundance and species composition in coastal waters of Dolsan, Yeosu, the fished were collected by gape net from March to November, 2000. The fish species caught by set net collected fishes were identified 63 species, 56 families, 42 orders, and the number of appearance and biomass was 2,230,297 individuals and 16,076.8kg. The most dominant orders were Perciformes, Clupeiformes and Tetraodontiformes which accounted for 71.4% of the total. The dominant species in number were Engraulis japonicus, Sardinops melanostictus, Trichiurus lepturus which accounted for 99.2% (2,211,642 individuals) of the total fishes collected. The dominant species in biomass were Engraulis japonicus which accounted for 79.7% (12,807g) of the total fishes collected. Temporal occurence of the dominant species such as the Engraulis japonicus, Sardinops melanostictus, Trichiurus japonicus, Ilisha elongata, Leiognathus nuchalis was closely correlated with water temperature, which is expressed as following regression equation, $y=0.0864x-0.2311(r^2＝0.3516)$. The species collected during the sampling yearly period were Engraulis japonicus, and migratory fish were Ilisha elongata, Trichiurus japonicus, Scomberomorus nipphnius, Scomber japonicus, Konosirus punctatus, Sphyraena pinguis, Pseudosciaena polyactis.

• 수산해양기술연구
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• 제50권2호
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• pp.131-138
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• 2014

The study aims at analyzing a species composition of the fish live in bottom of the coastal waters off Geomun island, Korea. To reach the goal of the study, a species composition and it's monthly fluctuation, a monthly fluctuation of the dominant species and it's appearance type was analyzed the fishes caught by the bottom trawl. The result obtained can be summerrized as follows; Fish caught in this area composes 14 orders, 34 families, and 47 species. The largest number of fish species was Perciformes (15 families and 19 species). The most dominant species in an number of fish was jhon dory, Zeus faber which was occupied at 22.5% from the whole number, the second most dominant species was horse mackerel, Trachurus japonicus which was occupied at 21.2%. Four groups were categorized based on appearance time period.

• 한국수산과학회지
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• 제24권5호
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• pp.356-361
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• 1991

This study was conducted to determine the decomposition rate constants of organic matter and to evaluate the process of regeneration of inorganic nutrients in coastal and open seawater. The mixture solution of glucose and glutamic acid, and night soil were used as the test organic matter. Oxygen uptake of test solution was observed every day for 5 days for evaluation of decomposition rate constants, and nutrient contents were analyzed every day for 40 days. The decomposition rate constants have been determined by Thomas slope method and compared with the values of each waters. The values of rate constants for open seawater and coastal water containing the mixture of glucose and glutamic acid were 0.23/day and 0.21/day, and those containing night soil 0.23/day and 0.20/day, respectively. The difference of decomposition rate constants between test materials was not found and the valus for each seawater was equal to each other. The nitrification process took place after 22 days for open seawater when night soil was added to the waters.

• 한국수산과학회지
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• 제23권5호
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• pp.385-393
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• 1990

전남 연안역에 출현하는 멸치 치어의 성장을 연구하기 위하여 전남 연안역의 3개 정점에서 1988년 5월부터 1989년 8월 사이에 정치망으로 멸치를 채집하였으며, 멸치의 연령은 이석에 나타난 성장선수로부터 결정하였다. 체장의 성장은 Gompertz의 성장식으로 표현하면 $$L =5.76{\times}E xp(1.66 \times(1- E xp(-0.44\;t)))$$, 또는 $$L=3.7{\times}E xp(1.99\times(1-E xp(-0.0614\;t)))$$로 표시된다. 20일부터 40일 사이의 평균 일일성장율은 0.38mm/day였으며, 일일성장율은 10일경에 최대를 보인후 서서히 감소하는 것으로 나타났다. 멸치의 성장은 채집시기나 채집장소에 관계없이 거의 일정한 것으로 나타났다.