• Proceedings of the Korean Aquaculture Society Conference
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• 2005.05a
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• pp.80-81
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• 2005

To investigate the food organisms of the Acanthogobius hasta during the juveniles stage, the stomach contents of fish, captured in the intertidal zone of Chungchong- nam-do Sochon-gun Su-myon Dodun-ri (Fig. 1) between on early June from end of May 2003, were observed. Total length of the juveniles of A. hasta was 5.5 mm ${\sim}$ 8.9 mm size, and the participation rate of feeding was 69.6%. Main food organisms were such as copepods, decapods, polychaete larvae, amphipods and these occupied more than dry weight 3.9%. Copepods among them dominated the most quantitys by average 62.7%, and next, food organisms appeared much by order of decapods, polychaete larvae and amphipods etc.. Therefore, most important food organisms of juvenile stage of A. hasta were copepods, decapods, polychaete larvae, amphipods etc.

• Proceedings of the Korean Aquaculture Society Conference
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• 2005.05a
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• pp.82-83
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• 2005

To investigate the food organisms of the Chaenogobius mororanus during the juveniles stage, the stomach contents of fish, captured in the intertidal zone of Chungchong- nam-do Sochon-gun Su-myon Dodun-ri (Fig. 1) between on early June from end of May 2003, were observed. Total length of the juveniles of C. mororanus was 5.0 mm ${\sim}$ 8.4 mm size, and the participation rate of feeding was 71.4%. Main food organisms were such as copepods, decapods, polychaete larvae, amphipods and these occupied more than dry weight 3.9%. Copepods among them dominated the most quantitys by average 62.0%, and next, food organisms appeared much by order of decapods, polychaete larvae and amphipods etc.. Therefore, most important food organisms of juvenile stage of C. mororanus were copepods, decapods, polychaete larvae, amphipods etc.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.60 no.2
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• pp.101-113
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• 2024

This study investigated the species composition and community structure of aquatic organisms captured using coastal beam trawling in Gomso Bay, Jeollabuk-do, from January to December 2022. Throughout the experimental period, a total of 20,246 individuals belonging to 94 marine species were captured, with a combined biomass of 602,828 g. Fish exhibited the highest abundance, comprising 56 species, followed by crustacea (21 species), bivalvia (8 species), cephalopoda (5 species), gastropoda (3 species), and holothuroidea (1 species). The dominant species was Leiognathus nuchalis, constituting 14.0% of the total individuals, followed by Portunus trituberculatus at 12.1%, Oratosquilla oratoria at 10.4%, Crangon hakodatei at 9.9%, and Metapenaeus joyneri at 7.9%. The diversity index ranged from 1.72 to 2.55, with the lowest diversity observed in March and the highest in July. Cluster analysis based on species composition of the 27 most common species showed that aquatic organisms were divided into three groups: spring and summer organisms (Group A) and summer organisms (Group B) and autumn and winter organisms (Group C).

• Environmental Analysis Health and Toxicology
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• v.16 no.2
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• pp.57-66
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• 2001

Marine organisms such as fish (Sebastes schlegeli) and mussels were cultured in sea water tanks placed at Dukpo area which was contaminated by the two oil spill accidents. Results showed that PAHs concentrations in flesh tissue were higher than in fish fiver. This was explained by the cytochrome P45O 1A induction in fish limier after PAHs exposure. Other studies showed that higher PAHs levels were detected in mussels cultures in oil contaminated area than in control site. From these results, we concluded that Dukpo area is still polluted by oil including PAHs and it takes a long time to recover of oil contamination after the oil spill accidents.

• Journal of Fisheries and Marine Sciences Education
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• v.26 no.1
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• pp.1-9
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• 2014

One of freshwater rotifer (Brachionus calyciflorus) is very useful as a live food organism for early larval rearing of freshwater aquaculture industry. However, the knowledge about freshwater rotifer culture is scarce. On the other hand, marine rotifer culture as live food organisms is done, almost perfectly. In this study, I show to be benefit experimental results for successful freshwater larval rearing through the observation with microcosm structure in freshwater rotifer culture tanks.

• Journal of Radiation Protection and Research
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• v.41 no.1
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• pp.1-6
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• 2016

Background: It is very difficult to set a regulatory guidance or criteria for the protection of non-human species from the ionizing radiation, because there are no generally or internationally accepted methods for demonstrating the compliance with such criteria. It is needed that Korea develop the primary dose rate standards for the protection of both aquatic and terrestrial biota in the near future. Materials and Methods: The potential dose rates due to both external and internal radiation exposures to marine organisms such as plaice/flounder, gray mullet, and brown seaweed collected within territorial seas around the Korean Peninsula were estimated. Results and Discussion: The total dose rates to plaice/flounder, gray mullet and brown seaweed due to $^{40}K$, a primordial radionuclide in marine environment, were found to be 0.2%, 0.08% and 0.3% of approximately the values of the Derived Consideration Reference Levels (DCRLs, i.e. $1-10mGy{\cdot}d^{-1}$), respectively, as suggested by the International Commission on Radiological Protection (ICRP) publication 124. The total dose rates to marine fishes and brown seaweed due to anthropogenic radionuclides such as $^{90}Sr$, $^{137}Cs$ and $^{239+240}Pu$ were considered to be negligible compared to the total dose rate due to $^{40}K$. The external exposure to benthic fish due to all radionuclides was much higher than that of pelagic fish. Conclusion: From this study, it is recommended that the further study is required to develop a national regulatory guidance for the evaluation of doses to non-human species.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.4
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• pp.345-350
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• 2010

We studied the organisms attached to Sargassum beds in Gamak Bay from November 2007 to June 2008. The water temperature ranged from 3.3 to $28.7^{\circ}C$ and salinity from 30.6 to 33.8 psu. Eighteen species $143,432\;ind./m^2$ were sampled during study periods. The biomass of the Sargassum beds ranged from a highest of $196.08\;g\;dw/m^2$ in March to a lowest of $0\;g\;dw/m^2$ in July. The major dominant species were Barleeia angustata ($134,430\;ind./m^2$), Caprellidae sp.($2,443\;ind./m^2$) and Gammaridae sp.($4,201\;ind./m^2$). The ecological indices of diversity, evenness, and richness were 0.11-0.86, 0.04-0.39, and 0.74-1.06, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.5
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• pp.576-588
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• 2017

Some of the mariculture grounds near Ongjin-gun, Korea, were designated as mariculture management areas in 2007. Areas are so designated when the environmental quality of the mariculture ground deteriorates or there is an outbreak of hypoxia or harmful red tide that kills mariculture organisms. We surveyed the water and sediment quality and examined the mortality of mariculture organisms in the Ongjin-gun mariculture area. In a survey conducted in 2016, the water quality was better than the environmental quality standards for mariculture grounds, excepts for dissolved inorganic nitrogen, and the sediment quality was good. However, there was still mortality of mariculture organisms in some of the designated management areas. The areas that met the environmental quality standards should be delisted and the areas in which we observed mortality should be classified as management areas. This will enable the sustainable development of aquaculture and preserve healthy mariculture grounds.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.5
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• pp.506-515
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• 2011

To elucidate demersal organism community structure, abundance, and biomass by period and region in the Uljin marine ranching area, otter trawl surveys were conducted at six stations from February 2008 to December 2009. During the survey period, a total of 118 species was collected in the Uljin marine ranching area, including 76 pisces, 27 mollusca and 15 crustaceans. The average abundance of individuals was 806 ind./$m^2$ and average biomass was 31,853 g/m2. The numbers of species, species richness, individuals per area and biomass per area were higher in 2009 than in 2008. Cluster and MDS analysis, based on a Bray-Curtis similarity matrix of fourth root transformed data of number of species and individuals per area, showed division into two different groups of demersal organisms in 2008 (Group 1) and one demersal organism community in 2009 (Group 2). From cluster and MDS analysis using the similarity of the demersal community among six stations, the Uljin marine ranching area was divided into Group A (St. 2, St. 4, St. 5 and St. 6) and Group B (St. 1 and St. 3).

• Biomolecules & Therapeutics
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• v.23 no.5
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• pp.479-485
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• 2015

This study was performed to investigate the sedative-hypnotic activity of ${\gamma}$-aminobutyric acid (GABA)-enriched fermented marine organisms (FMO), including sea tangle (FST) and oyster (FO) by Lactobacillus brevis BJ20 (L. brevis BJ20). FST and FO were tested for their binding activity of the $GABA_A$-benzodiazepine and 5-$HT_{2C}$ receptors, which are well-known molecular targets for sleep aids. We also measured the sleep latency and sleep duration during pentobarbital-induced sleep in mice after oral administration of FST and FO. In $GABA_A$ and 5-$HT_{2C}$ receptor binding assays, FST displayed an effective concentration-dependent binding affinity to $GABA_A$ receptor, similar to the binding affinity to 5-$HT_{2C}$ receptor. FO exhibited higher affinity to 5-$HT_{2C}$ receptor, compared with the $GABA_A$ receptor. The oral administration of FST and FO produced a dose-dependent decrease in sleep latency and increase in sleep duration in pentobarbital-induced hypnosis. The data demonstrate that FST and FO possess sedativehypnotic activity possibly by modulating $GABA_A$ and 5-$HT_{2C}$ receptors. We propose that FST and FO might be effective agents for treatment of insomnia.