• Journal of the Korean Society for Marine Environment & Energy
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• v.10 no.1
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• pp.21-28
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• 2007

The bioaccumulation of Pb and Cd dissolved in seawater was assessed measuring the concentrations recorded within blue mussel (Mytilus edulis) and oliver flounder (Paralichthys olivaceus) after two weeks exposure period. The Pb and Cd concentration within the whole body of two testing organisms increased according to the exposure concentrations, and the such tendency was clear specially from the mussel. Maximum metal concentration reached $5,260({\pm}70)\;{\mu}g/g$ for Pb reared under 5.0 mg/L Pb, $1,040({\pm}40)\;{\mu}g/g$ for Cd reared under 1.0 mg/L Cd in the mussel, and indicated that the bioaccumulation of Pb and Cd was directly related to the rearing medium concentrations. Bioconcentration factors (BCF) reached very high values for Pb (maximum value: $12,100{\pm}1,400$) in the mussel reared under lowest Pb concentration (0.01 mg/L). The BCF value for Cd in the mussel were also far higher at exposure to low Cd concentration than high Cd concentration. At higher external concentrations, the BCF for Cd and Pb declined. This demonstrated the ability of two testing organisms to rapidly uptake heavy metals particularly when exposed to low external concentration. The mean Pb concentration was slightly higher in the gill of mussel than in the digestive gland, while Cd showed a higher level in the digestive gland than in the gill.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.2
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• pp.222-226
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• 2017

It is well known that typhoons strongly influence marine ecosystems. For example, red tides nearly disappear after the passage of typhoons, although the physical or biological mechanism underlying this has not been elucidated. Here, a particle tracking model is executed in a three-dimensional primitive equation model to understand the process of red tide extinction after the passage of a typhoon. Red tide organisms may be regarded as tracers because they have limited mobility and thus their behavior is governed entirely by currents. Initially, tracers are randomly scattered within a limited area, and their spatial and temporal behavior is tracked during and after the passage of a typhoon. This model suggests that the extinction of red tides is significantly influenced by momentum disturbances caused by the typhoon.

• Journal of the Korean Society of Marine Environment & Safety
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• v.8 no.2
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• pp.23-27
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• 2002

Reballasting at sea, as recommended by the IMO guidelines, currently provides the best-available measure to reduce the risk of transfer of harmful aquatic organisms, but is subject to serious ship-safety limits. It is therefore extremely important that alternative, effective ballast water management and treatment methods are developed as soon as possible, to replace reballasting at sea. Filtration-Ultraviolet radiation-Electrolytic process (FUE) was evaluated for disinfection of seawater used In ballast water Optimal current density and UV light intensity were 2.0A/dm$^2$ and, 220㎼/$\textrm{cm}^2$/m with which 100% reduction time was 2sec in a Ultraviolet radiation-Electrolytic process. This study showed that FUE process was effective for the disinfection of commonly isolated bacteria and bacillus from ballast water.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.5
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• pp.351-362
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• 1989

Ecology of Crangon affinis was studied in the Nakdong River Estuary fron June 1988 to May 1989. The growth rate of female was similar to that of male. Size differences, however, were apparent between female and male. Sex ratio varies with season. The major spawning season was from June 1988 to May 1989 except for November 1988. The number of eggs of the largest ovigerous female (35.55mm TL) was over 4,000, while that of the smallest ovigerous female (15.05mm TL) more than 120. The mean number of eggs was 1778. The size of winter eggs is larger than that of the summer eggs. The mean percentage of egg loss from brooding to hatching was $29.06\%$. The rate of egg loss decreases with increasing age. Major component of food organisms includes mysids and polycheates.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.229-230
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• 2003

Shortnecked clam is a commercially important mollusks species, which is distributed all over the Yellow Sea. Consequent of the rapid increase in seed production, there is a need to understand the genetic composition of wild shortnecked clam populations in order to evaluate exactly the latent genetic effects induced by seed production operations. Many genetic and molecular researches were made because RAPD-PCR is a simple and rapid method for determining genetic diversity and similarity in various organisms with the advantage that no prior knowledge of the genome under research is needed (Fischer et at., 2000). (omitted)

• Journal of Environmental Impact Assessment
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• v.20 no.2
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• pp.199-205
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• 2011

The Saemangeum embankment construction have changed the flowing on the topography of the coastal marine environment. However, the variety of ecological factors are changing from outside of Saemangeum embankment area. The ecosystem of various marine organisms have led to changes by sea surface temperature. The aim of this study is to monitoring of sea surface temperature(SST) changes were measured by using thermal infrared satellite imagery, MODIS and Landsat. The MODIS data have the high temporal resolution and Landsat satellite data with high spatial resolution was used for time series monitoring. The extracted informations from sea surface temperature changes were compared with the dyke to allow them inside and outside of Saemangeum embankment. The spatial extent of the spread of sea water were analyzed by SST using MODIS and Landsat thermal channel data. The difference of sea surface temperature between inland and offshore waters of Saemangeum embankment have changed by seasonal flow and residence time of sea water in dyke.

• Journal of Marine Bioscience and Biotechnology
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• v.2 no.2
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• pp.77-80
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• 2007

Macroalgal tissues can be used as indicating materials for environmental assessment using several algal biotechnology techniques. As bioassay test organisms, macroalgal tissues are required as an axenic state for suitable biological indicators. Callus formation and blade regeneration under suitable culture conditions are also useful for the tests. Quantitative method using tetrazolium chloride or $alamarBlue^{TM}$ is devised on a rapid assessment of the seaweed viability. The use of RT-PCR especially differential display technique should provide the means for the detection and isolation of the responding genes induced by the environmental stress. Seaweed thriving in more environmental changes might contain more diverse biologically active substances.

• Journal of the Korean Chemical Society
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• v.33 no.3
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• pp.321-325
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• 1989

There has been a continuing interest in the sterols and sterodis of marine organisms. The most exciting results of recent studies have been the characterization of a host of novel sterols, many with unique alkylation patterns in the side chain, but some with modified ring structures. The isolation and characterization of three sterols from the Korean alga codium fragile are presented. The major sterol was (24S)-24-ethylcholesta-5,25-dien-3${\beta}$-ol (clerosterol) and two minors are codisterodl and cholesterol.

• Journal of Marine Bioscience and Biotechnology
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• v.5 no.4
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• pp.26-32
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• 2011

Green fluorescent protein (GFP), a very important biological agent that involves shifting the color of bioluminescence from blue to green in luminous coelenterates and to increase the quantum yield of light emission. GFP discovered in medusa, Aequorea victoria is a key factor of various biotechnological and cell biological applications. Beside these applications, GFP of A. victoria is generally stable, which does not require co-factors for activity and can be functionally expressed in different bacterial species. This property of GFPs from A. victoria permits them to be a unique tool to monitor gene expression and protein localization in different organisms. The present review brings out the past milestones and future perspectives on GFPs, with an elaborative reviewing on its applications.

• Animal Systematics, Evolution and Diversity
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• v.36 no.4
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• pp.408-415
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• 2020

The suborder Hyperiidea is an abundant crustacean zooplankton in pelagic communities with copepods and euphausiaceans. Hyperiidean amphipods are known to be commensals or parasites of gelatinous organisms such as medusae, siphonophores, ctenophores, and salps. Korean hyperiid amphipods have not received taxonomical attention since the 1970s. During a survey of pelagic crustacean species, two species of hyperiid amphipods, Phronima atlantica Guérin-Méneville, 1836 belonging to the family Phronimidae and Oxycephalus clausi Bovallius, 1887 belonging to the family Oxycephalidae, were found on Dokdo, East Sea, Korea. These two species are new to Korean waters. In the present study, we provide descriptions and illustrations of these two hyperiid species.