• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.4
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• pp.526-531
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• 2021

The diet composition of john dory Zeus faber, was investigated using 266 specimens collected in the coastal waters of the South Sea, Korea. The specimens ranged in total length (TL) from 12.5 to 43.2 cm. The Z. faber fed mainly on Pisces and less often on Macrura. We further analyzed the data by dividing the specimens into five classes (<15.0 cm, 15.0-20.0 cm, 20.0-25.0 cm, 25.0-30.0 cm, ≥30.0 cm). The Z. faber diet shifted with size class from predominantly consuming Macrura to Pisces. The proportion of Macrura consumed decreased with increasing body size, whereas the consumption of Pisces increased gradually.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.10a
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• pp.288-289
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• 2000

일반적으로 수산자원생물은 본능적으로 자기 자신에게 가장 적합한 환경에서 생활하게 되며 또한 이런 적합한 환경이 재생산력을 높여 각 개체군의 번영을 조장한다. 각 개체군은 수온, 염분, 투명도, 해류, 해저지형, 저질, 먹이생물 등의 호적한 조건을 가진 장소로 찾아 이동하거나 모이게 되며, 주로 성장기의 먹이를 찾는 색이회유나 성숙에 따른 산란회유, 겨울을 지나기 위한 월동회유 등을 계절에 따라 반복하게 된다(Hardoen Jones, F.R., 1968). (중략)

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2019.05a
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• pp.249-251
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• 2019

본 연구는 수산자원, 어항기반시설을 바탕으로 어촌뉴딜300사업 수산특화형 사업의 모델을 제시하였음. 수사자원이 풍부하고 어민들의 참여가 높은 갈화마을에서 수산특화형 사업의 성공 가능성을 발견할 수 있었음.

• Korean Journal of Ichthyology
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• v.33 no.1
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• pp.37-42
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• 2021

This study sought to reveal spawning period and sex inversion of black seabream, Acanthopagrus schlegelii collected off the coast of Tongyeong, Korea. The monthly gonodosomatic index (GSI) showed the same pattern of between both sexes, and it was estimated that black seabream spawned once a year (between April and May). Histological examination revealed the transition from male to female sex, size of fork length bisexual gonad with ovarian (primary hermaphrodite; progress from male to female, MF) was seen at 20.5 to 39.6 cm and bisexual gonad with testicular (post hermaphrodite; female development and Male degeneration, FM) was seen at 26.4 to 50.2 cm. The egg diameters was in the range of 0.02 to 0.60 mm, with the smallest average egg diameter of 0.09 mm in February, the highest average egg diameters of 0.43 mm in August, and the range of fecundity was number of eggs 277,148 (33.9 cm) to 2,772,421 (34.1 cm).

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.54 no.4
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• pp.271-278
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• 2018

In this study, the conventional cylinder-shaped lower bar on the canvas was modified and its performance was tested to improve the opening force of the stow net on anchor. The improved new lower bar used in the test is consisted of 13 flat bars with a length of 1.8 m, a width of 0.075 m and a thickness of 4 mm, and a pipe with a length of 2.0 m and a diameter of 50 mm. A stow net with the improved lower bar and a stow net with an existing lower bar were installed underwater and their trajectories for 21 hours were examined. To confirm their trajectories, GPS loggers were attached to the buoys on the left and right canvases and the buoy of the hauling rope. As a result of the test, the rotation of the gear with the improved bar was smoother than that with the existing bar. As a result of comparing the changes in the interval of the buoys attached to the canvas after the low and high tide, the buoy spacing of the gear with the improved bar is wider than that of the conventional gear; moreover, the larger the interval, the smoother the rotation of the fishing gear was. Therefore, it is considered that using the improved lower bar can enhance the performance of the stow net.

• Journal of Environmental Science International
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• v.30 no.7
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• pp.585-595
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• 2021

We used seawater temperature data, measured in the Garolim Bay, to analyze temperature variation on an hourly and daily basis. Lagrange's interpolation using before and after data was applied to restore nonconsecutive missing temperature data. The estimated error of the data restoration was 0.11℃. Spectral analyses of seawater temperature showed significant periodicities of approximately 12.4 h (semidiurnal tide) and 15.0 d (long-period tide), which is close to those of M₂ and M_f partial tides. Variation in seawater temperature was correlated more with tidal height than with air temperature around the Garolim Bay. In June and December, when the seawater temperature difference between the inside and outside of the Garolim Bay was very large, the periodicities of 12.4 h and 15.0 d were highly prominent. These results indicate that the exchange of seawater between the inside and outside of the Garolim Bay induced variations in seawater temperature owing to tide. Understanding temperature variation because of tide helps to prevent abnormal mortality of cultured fish and to predict seawater temperature in the Garolim Bay.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.5
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• pp.514-523
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• 2022

Concentrations of perfluoroalkyl substances (PFASs) were measured in seawater, sediment, and biota collected from Gunsan coast, Korea to investigate their occurrence, distribution, and risk of exposure to humans through seafood consumption. The total concentrations of PFASs in seawater, sediment, and biota ranged from 5.97 to 74.9 ng/L, 0.01 to 13.3 ng/g dry weight, and 0.02 to 5.73 ng/g wet weight, respectively. Predominant PFAS compounds differed across matrices, indicating that the distribution of PFASs in multiple environmental samples is governed by their carbon-chain length. The concentrations of PFASs in seawater were significantly negatively correlated with salinity (P<0.01), suggesting terrestrial input (including land-used PFASs) as the major source of PFAS contamination in coastal environments. The estimated daily intakes (EDIs) of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) through seafood consumption were 0.05 and 0.06 ng/kg body weight/day, respectively. The EDIs of PFOA and PFOS measured in this study were lower those the proposed by the United States Environmental Protection Agency and Canada guidelines, indicating limited health risk for Korean population from PFASs through consumption of seafood from Gunsan coastal environment.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.82-83
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• 2000

수산 생물의 종에 따른 생물학적 다양성은 각기 독특한 성질을 갖는 다양한 효소들이 분포한다는 것을 의미하기도 한다. 이러한 이유로 다양한 효소자원으로서 수산동물의 가공 부산물 또는 폐기물로부터 소화 관련 효소(digestive enzymes)의 회수와 산업적 이용의 잠재성은 매우 크다고 할 수 있다. 수산동물의 소화 관련 효소는 pepsin(Gildberg et al., 1990;1991), chymotrypsin, trypsin(Heu et al, 1995), gastricsin(Sanchea- Chiang and Ponce, 1981) 그리고 elastase(Bjarnason et al., 1993)을 상으로 연구가 이루어지고 있다. 특히 수산동물과 같이 저온에 적응한 냉혈동물의 단백질분해효소는 육상의 온혈동물의 동종 효소보다 낮은 최적온도와 온도안정성 때문에 식품산업에 응용성이 넓다고 하겠다. 따라서 우리나라의 다양한 수산자원의 폐기물 및 가공부산물로부터 소화 관련 효소를 분리하여 식품산업에 있어서 가공보조제(processing aids)로서 이용 가능하리라 생각된다. (중략)

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.3
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• pp.318-328
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• 2021

We investigated the maturity and spawning of the brown sole Pseudopleuronectes herzensteini, in the coastal waters of the East Sea off Gangwon and Gyeongbuk, South Korea, using samples collected by gill net and longline fishery from January 2018 to December 2019. We analyzed oocyte development, monthly maturity stage, gonadosomatic index (GSI) and total length at maturity. Histological analysis of ovarian development in P. herzensteini revealed that the development was group-synchronous. The spawning peak in Gangwon and Gyeongbuk occurred from April to May and from February to March, respectively. Thus, the spawning season in Gangwon was 1-2 months later than that in Gyeongbuk. The length at 50% maturity for females was estimated as 24.2 cm and 19.0 cm in Gangwon and Gyeongbuk, respectively. Similarly, the length at 50% maturity for males was estimated as 19.8 cm and 16.5 cm in Gangwon and Gyeongbuk, respectively.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.59 no.3
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• pp.231-241
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• 2023

This study was investigated in order to find composition and density of fisheries resource using bottom trawl in April, July, August, and November 2022 in the East China Sea. The average density of fisheries resource was estimated using the swept area method. As a result, 35 species were collected from the East China Sea. These included 21 fishes, six crustaceans, six cephalopods and two echinoderms. Seasonally, the average density of crustacean individuals per unit area were highest in November (692.1 inds./km²), while cephalopod individuals per unit area were highest in August (39.4 inds./km²). The average density of fish individuals per unit area were highest in August at 355.0 (inds./km²).