• Korean Journal of Fisheries and Aquatic Sciences
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• v.12 no.2
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• pp.119-123
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• 1979

The cute toxicity test of mercury, cadmium and copper to yellowtail, Seriola quinqueradia, and to rock-bream, Oplegnathus fasciatus, were conducted by static bioassays from 18 July to 27 October, 1978. In the tests, tile least sensitive heavy metals were cadmium to rock bream and copper to yellowtail. The test species were most sensitive to mercury among all the chemicals used. The 24hr-LC 50 value for the yellowtail was 0.11mg/l for mercury, 0.82mg/l for cadmium and 1.03mg/l for copper. While the 48hr-LC 50 value for the rock bream was 1.40mg/l for mercury and 1.73mg/l for copper.

• Journal of Species Research
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• v.5 no.3
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• pp.517-529
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• 2016

Two scale worms of the family Polynoidae, Arctonoe vittata (Grube, 1855) and Hyperhalosydna striata (Kingberg, 1856) were found for the first time from Korea by SCUBA diving survey. The two species are free-living organisms or associated commensally with a wide variety of other invertebrates. Specimens of A. vittata were collected from the East Sea and were closely associated with asteroids, holothuroids, gastropods and nudibranchs species. Specimens of H. striata were collected from Jeju-do Island, and of these, one specimen was collected in a tube of eunicid species. The two species can be easily distinguished from their congeners by distinct morphological characteristics as follows: (1) A. vittata has pigmented band near segment eight and two kinds of neurochaetae; (2) H. striata has reddish-brown longitudinal striped elytra. The morphological key characteristics of both species agreed well with their original descriptions and redescriptions. In this study, the descriptions, detailed illustrations and ecological photographs of two species based on Korean materials were provided.

• The Korean Journal of Malacology
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• v.21 no.1
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• pp.19-24
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• 2005

This study was undertaken with the intent to describe the influence of water temperature and food concentration on the filtration rates of the Asiatic clam, Corbicula fluminea. The clams were collected at Lake Geumho near Yeongsan river, during March 2001. Food organism, Scenedesmus sp. (KMCC FC-34), was indoor-cultured in f/2 medium, and was used to measure the filtration rate of the clams. Filtration rate of the clams was measured by indirect method. Cell concentrations of food organisms were determined by direct counting cells using the hemacytometer under the light microscope. The filtration rate of the clams increased with water temperature up to circa $25^{\circ}C$. Above this temperature, the filtration rate decreased rapidly. The minimal filtration rate of the clams was recorded at $5^{\circ}C$. Thermal coefficient, $Q_10$ values at low temperature range were much higher than those at high temperature range. These results indicate the asiatic clam is more sensitive in cold water like most of marine bivalves. There was a strong reversed correlation between filtration rate and food concentration. Filtration rate of the clams was reduced as food concentration was increased.

• Journal of Environmental Science International
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• v.26 no.5
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• pp.639-649
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• 2017

Measurements of polychlorinated biphenyls (PCBs) were taken in surface sediments inside Seogwipo and Hallim Harbors of Jeju Island, Korea, to evaluate their distribution. These harbors typically have heavy ship traffic. The samples were collected three times (in June, October, and December, 2013). PCB concentrations in sediments from Seogwipo Harbor were higher than in those from Hallim Harbor, but both levels were very low, compared with those in other parts of the world. Sedimentary PCB levels had a strong correlation with organic carbon and fine granule mud content. PCB concentration values in the examined surface sediments were much lower than Sediment Quality Guidelines (SQGs) such as ER-L (Effect Rrange-Low), TEL (Threshold Effects Level) and ISQG (Interim Sediment Quality Guideline)-low value applied in countries, such as USA, Canada, and Australia. This suggests that the PCBs did not have significant biological effects on benthic organisms in the marine environment.

• Fisheries and Aquatic Sciences
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• v.19 no.7
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• pp.31.1-31.6
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• 2016

Background: The objective of this study was to develop an efficient selectable marker for transgenic Dunaliella salina. Results: Tests of the sensitivity of D. salina to the antibiotic chloramphenicol and the herbicide Basta$^{(R)}$ showed that cells ($1.0{\times}10^6cells/ml$) treated with 1000 or $1500{\mu}g/ml$ chloramphenicol died in 8 or 6 days, respectively, whereas D. salina cells ($1.0{\times}10^6cells/ml$) treated with 5, 10, 20, or $40{\mu}g/ml$ Basta$^{(R)}$ died in 2 days. Therefore, D. salina is more sensitive to Basta$^{(R)}$ than to chloramphenicol. To examine the possibility of using the phosphinothricin N-acetyltransferase (pat) gene as a selectable marker gene, we introduced the pat genes into D. salina with particle bombardment system under the condition of helium pressure of 900 psi from a distance of 3 cm. PCR analysis confirmed that the gene was stably inserted into the cells and that the cells survived in $5{\mu}g/ml$ Basta$^{(R)}$, the medium used to select the transformed cells. Conclusions: The findings of this study suggest that the pat gene can be used as an efficient selectable marker when producing transgenic D. salina.

• ALGAE
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• v.22 no.2
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• pp.141-146
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• 2007

Seagrass bed is an important component in coastal and estuarine ecosystems, providing food and habitats to a wide variety of marine organisms. Recently, seagrass coverage has declined significantly due to anthropogenic impacts such as cultural eutrophication and reclamation, and thus efforts are under way to prevent further losses and restore disturbed seagrass habitats worldwide. Seagrass transplantation techniques for habitat restoration include vegetative and seed-based methods. Seagrass seeds can be collected easily, and sowing seeds is an economically effective method for large-scale restoration. However, large numbers of seed can be lost by seed predation and physical disturbance in the planting areas. In the present study, Zostera marina seeds were coated with loess to reduce seed loss by predation and sweeping away by the water currents, and germination rates of coated seeds and seedling growth were examined to assess the feasibility of the seed-coating method for large-scale restoration. Germination rate of the coated seeds with loess was significantly higher than that of the uncoated seeds. Additionally, seedling growths were not significantly different between the coated and the uncoated seeds. These results suggest that coating of eelgrass seeds with loess enhances success of seed germintion with no harmful effects on seedling growth. Therefore, the seed coating method using loess may be an effective and applicable seedbased transplanting technique for large-scale restoration.

• ALGAE
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• v.22 no.3
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• pp.221-228
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• 2007

Frequent occurrences of green tides caused by Ulva species (Ulvales, Ulvophyceae) associated with eutrophication along enclosed coasts are currently causing environmental problems in coastal ecosystems. In addition, increasing intercontinental introductions of coastal marine organisms, including Ulva, are also a serious issue. However, due to the considerable morphological plasticity of this genus, the taxonomy of Ulva species based on morphological studies is problematic. Therefore, in order to elucidate the species diversity and seasonal changes of the dominant Ulva species in Mikawa Bay, central Honshu, Japan, we made seasonal collections of Ulva species at seven localities, and identified the dominant species using the ITS2 rDNA region sequences. We identified the following nine taxa as common Ulva species in the area: 1) Ulva pertusa Kjellman; 2) U. ohnoi Hiraoka et Shimada; 3) U. linza L.; 4) U. californica Wille; 5) U. flexuosa Wulfen; 6) U. fasciata Delile; 7) U. compressa L.; 8) U. armoricana Dion et al.; 9) U. scandinavica Bliding. Among the species, U. pertusa was most common and dominant from spring to summer, and U. ohnoi from autumn to winter. Ulva californica and U. scandinavica have not been reported before from Japan.

• Journal of the korean society of oceanography
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• v.37 no.2
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• pp.82-89
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• 2002

Butyltins (BTs) were measured in 2 species of shellfish and 16 species of fish collected along the Korean coast. Tributyltin (TBT) was detected in the mussels and oysters of sentinel organisms (20 to 940 ng Sn/g dry wt), indicating widespread contamination of TBT in the Korean coast. The elevated concentrations of TBT in the shellfish found in the sites near harbors or shipyards suggested that antifouling paints are probable major sources of butyltins in these areas. The TBT compound was detected in 12 out of 16 fish samples. The concentrations of TBT in fish muscles wee between 7 and 151 ng Sn/g dry wt, while the level in whole body of anchovy was very high (793 ng Sn/g dry wt). Exposure doses to Korean people via consumption of these marine products wee evaluated. The results suggested that the environmental levels of TBT were below the level of concern.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.17 no.3
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• pp.189-201
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• 2012

Radiocarbon is a powerful tool for studies of carbon cycling in the ocean. Development of measurement technology of accelerator mass spectrometry has enabled researchers to measure radiocarbon even in specific compounds. In this paper, a brief introduction on radiocarbon measurement and reporting of radiocarbon data is provided. Researches that used radiocarbon measurements on bulk organic matter, organic compound classes, and specific organic compounds are reviewed. Examples include works to understand the cycling of particulate and dissolved organic matter, biochemical composition of particulate organic matter, post-depositional transport of sedimentary organic matter, selective incorporation of fresh organic matter by benthic organisms, chemoautotrophy by archaea, and sources of halogenated chemical compounds found in marine mammals.

• Korean Journal of Environmental Biology
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• v.31 no.1
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• pp.10-18
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• 2013

Oil spills have occurred throughout the years of industrialization and represent a global challenge as they affect vast areas of the ocean. The toxicity of crude oil to aquatic organisms has been extensively investigated, but the potential impacts of crude oil on vertebrate development remain largely unknown. Here, we investigated the effects of dispersants used in treating a recent oil spill, as well as that of crude oil, on vertebrates by using the zebrafish (Danio rerio) model species, which has been widely used in empirical studies of both early embryonic development and adult physiology. Chronic exposure to crude oil resulted in marked developmental abnormalities, including pericardial edema, abnormal trunk vessel development, retardation of axonal branching, and abnormal jaw development. Embryonic development was affected more severely by exposure to the oil-dispersant combination than to the oil alone. Thus, the zebrafish in vivo model system suggests that dispersant treatment can have detrimental developmental effects on vertebrates and its potential impact on marine life, as well as humans, should be carefully considered in clean-up efforts at the site of an oil spill.