• The Korean Journal of Malacology
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• v.24 no.3
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• pp.215-228
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• 2008

This study was performed to find out the community structure of macrobenthos and the environmental factors around Munseom coastal water in Jeju Island from June to December, 2007. Mean temperature and mean salinity were $19.6^{\circ}C$ and 34.03 psu, indicating stable water masses. Concentrations of DO, COD and SS were as low as those in the standard sea-water-quality classes I. Chlorophyll a concentrations ranged from 0.40 to 1.09 mg/L (mean, 0.69 mg/L), and higher concentration was observed in December rather than in June due to a blooming in winter. The mean concentration (their ranges are in parentheses) of nitrate, phosphate, and silicate were 0.15 mg/L (0.073-0.264 mg/L), 0.01 mg/L (0.004-0.011 mg/L) and 0.23 mg/L (0.039-0.464 mg/L), respectively. The values were higher near the Munseom due to influxes from the land. Of the 112 species that were identified, 40 species (36.0%) were Mollusca; 33 (28.8%) were Cnidaria; 13 (11.7%) were Porifera; 8 (7.2%) were Arthropoda and 17 species (15.3%) were others including Echinodermata. Density and biomass were estimated to be 4,340 individual/$m^2$ and $53,107.8\;gwwt/m^2$ respectively. Anthozoa was the most dominant group in abundance ($2,132\;ind./m^2$) as well as in the number of species, whereas Cnidaria was predominant in biomass ($37,630.9\;gwwt/m^2$). The dominant species were Dendronephthya gigantea, Scleronephthya gracillimum, Anthoplexaura dimorpha, Dendronephthya castanea, Thecocarpus niger, Dendronephthya spinulosa, Dendronephthya putteri, and Acabaria bicolor in the depth of 10-30 m. The seasonal variations of the number of individual and biomass of Cnidaria and Mollusca were observed. There was a slow increment in June, a decrement in October, and a drastic increasing in December. The biodiversity, evenness and richness index in surveyed stations were 2.715-3.413 (H'), 0.758-0.851(E'), and 5.202-8.720 (R) respectively. The dominance index was the highest in station M2 and the lowest in station M1.

• Economic and Environmental Geology
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• v.53 no.6
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• pp.729-742
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• 2020

In this study, we analyze seabottom conditions and characteristics integrated with topographic data, seafloor mosaic, underwater images and orthophoto(drone) of soft-hard bottom area around the Sib-Ri rock in the northern shore of the East Sea(Gyeongpo Beach, Gangneung). We obtained field survey data around the Sib-Ri rock(about 600 m × 600 m). The Sib-Ri rock is formed by two exposed rocks and surrounding reef. The artificial reef zone made by about 200 ~ 300 structures is shown the western area of the Sib-Ri rock. The underwater rock region is extended from the southwestern area of the exposed the Sib-Ri rock with 9 ~ 11 m depth range. The most broad rocky seabottom area is located in the southwestren area of the Sib-Ri rock with 10 ~ 13 m depth range. The study area were classified into 4 types of seabottom environment based on the analysis of bathymetric data, seafloor mosaics, composition of sediments and images(underwater and drone). The underwater rock zones(Type I) are the most distributed area around the Sib-Ri Rock(about 600 m × 600 m). The soft seabottom area made by sediments layer showed 2 types(Type II: gS(gravelly Sand), Type III: S(Sand)) in the areas between underwater rock zones and western part of the Sib-Ri rock(toward Gyeongpo Beach). The artificial reef zone with a lot of structures is located in the western part of the Sib-Ri rock. Marine algae(about 6 species), Phylum porifera(about 2 species), Phylum echinodermata(about 3 species), Phylum mollusca(about 3 species) and Phylum chordata(about 2 species) are dominant faunal group of underwater image analysis area(about 10 m × 10 m) in the northwestern part of the Sib-Ri rock. The habitat of Phylym mollusca(Lottia dorsuosa, Septifer virgatus) and Phylum arthropoda(Pollicipes mitella, Chthamalus challengeri hoek) appears in the intertidal zone of the Sib-Ri rock. And it is possible to estimate the range and distribution of the habitat based on the integrated study of orthphoto(drone) and bathymetry data. The integrated visualization and mapping techniques using seafloor mosaic images, sediments analysis, underwater images, orthophoto(drone) and topographic data can provide and contribute to figure out the seabottom conditions and characteristics in the shore of the East Sea.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.6
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• pp.853-865
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• 2022

In this study, from August to October 2019, we conducted a survey of the spatial distribution and dominant species of macrobenthos on the rocky intertidal zones of 38 specified islands distributed along the southern coast of Korea. On the basis of observation made using 50 × 50 cm quadrats, we identified a total of 80 species, among which, Mollusca were the most abundant fauna, with 54 species that accounted for 67.4% of the total, followed by Crustacea with 15 species (18.7%). The recorded numbers of Cnidaria, Porifera, and Echinodermata species ranged from 1 to 6. In terms of the regional patterns of species richness, specified islands in Yeosu were found to be the most species rich, supporting 61 species, whereas islands in Hadong, Namhae, and Chujado were found to have a similar level of species richness, ranging from 42 to 46 species. Islands in Boseong and Goheung were home to the fewest species, with only 29 species being recorded. At the sampling station scale, we noted a considerable difference in faunal richness, ranging from 6 (St. 6) to 33 (St. 20) species. Among the recorded species, Echinolittorina radiata was identified as the dominant species on 15 specified islands, with the next most abundant species being Tetraclita japonica, considered an indicator species of climate change, which was recorded on 11 islands. In terms of frequency, E. radiata, found on 36 islands, was identified as the most frequently occurring species, followed by Reishia clavigera (30 islands), Mytilisepta virgata (29), Nerita japonica (28), Ligia. exotica (27), and Littorina brevicula (26). Of the 80 species identified, 9, 4, and 2 species of Mollusca, Crustacea, and Cnidaria, respectively, are classified as Marine fauna of accepted foreign export, whereas 50 are Red List species, 44 are species of Least Concern, 3 are Data Deficient species, and 1 species was not evaluated. However, during the survey, we found no Near Threatened or Not Applicable species. On the basis of the findings of this survey, it would appear that the abundance and richness of macrobenthic fauna inhabiting the rocky intertidal zones of specified islands along the southern coast of Korea differ according to different habitat conditions, particularly with respect to the duration of exposure and the extent and properties of the substrata. The findings of this study will provide baseline data for future monitoring and management of specified islands in Korea.

• Korean Journal of Environment and Ecology
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• v.18 no.1
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• pp.75-91
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• 2004

Biodiversity and seasonal community composition of benthic macroinvertebrates were studied from Upo wetlands in Gyeongsangnam-do, Korea, comprising Upo (4 sites), Mokpo (2 sites), Sajipo (1 site), Jjokjibeol (1 site), Yeobeol (1 site), and Topyeongcheon (2 sites) areas from October 2002 to August 2003. As a result, it was known that Upo wetlands retained relatively well-preserved littoral zones which may provide good habitats for benthic macroinvertebrates; however, frequent disturbances of littoral zones caused by flood were the major factor affecting on the survival and distribution of benthic macroinvertebrates in the areas. During the study period, a total of 135 species of benthic macroinvertebrates in 10 genera, 59 families, 16 orders, 7 classes, and 3 phyla were collected those of which are the highest degree of diversity of the taxa ever known in Korean wetlands: aquatic insects 103 spp. (Diptera 27 spp., Odonata 24 spp., Coleoptera 19 spp., Hemiptera 16 spp., Ephemeroptera 9 spp., Trichoptera 7 spp., and Collembola 1 sp.), Crustacea 2 spp., Mollusca 19 spp. (Gastropoda 12 spp. and Bivalvia 7 spp.), and Annelids 11 spp. (Oligocaeta 1 sp. and Hirudinea 10 spp.). Sajipo (St.G) and Jjokjibeol (St.H) areas yielded relatively larger numbers of species, 54 spp. and 53 spp., respectively, while more than 40 species occurred at most other sites. Based on quantitative sampling (0.5m${\times}$2m), aquatic insects (88.0％), particularly chironomids in Diptera (61.0％), occupied major proportion of the total individuals of benthic macroinvertebrates, while Mollusca (5.3％), Annelida (3.5％), and Crustacea (3.2％) occupied minor proportions. In standing water areas, diverse groups of benthic macroinvertebrates such as chironomids, demselflies, aquatic bugs, aquatic beetles, crustaceans, and gastropods were dominant in terms of individual number; in the running water areas, on the other hand, chironomids and baetid mayflies were dominant. However, gastropods, i.e. viviparids, were the dominant group of benthic macroinvertebrates in most study areas in terms of biomass. Dominance indices were 0.22-0.51 (mean$\pm$sd 0.42$\pm$0.09) in autumn, 0.31-0.96 (0.02$\pm$0.23) in winter, and 0.30-0.89 (0.57$\pm$0.18) in summer; diversity indices were 3.50-4.26 (3.80$\pm$0.24) in autumn,1.55-4.50 (3.10$\pm$1.01) in winter, and 1.35-3.77 (2.55$\pm$0.09) in summer. Highly movable or true aquatic benthic macroinvertebyates such as aquatic bugs, aquatic beetles, and gastropods recovered earlier after flood. In the study sites of Upo wetlands, Upo and Sajipo areas showed relatively higher values of average diversity index which may indicate a good habitat condition for benthic macroinvertebrates.

• The Korean Journal of Malacology
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• v.12 no.2
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• pp.109-121
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• 1996

Histochemical experiment was carry out respectively to confirm the properties of the salis (Achatina fulica and Incilaria fruhstorferi). SDS-PAGE was carried out to compare and invertigate the distribution aspects of protein patterns between the two species. Five types(A, B, F, H and I)of gland cells with four neutral mucopolysaccharide cells and one acid mucopolysaccharide cells and one acid mucopolysaccharide cell were observed in acinous of Achatina fulica, while six types were observed in acinous of Incilaria fruhstorferi: ond acid mucopolysaccharide cell(type-A) and four neutral mucopolysaccharide cells(type-B, C, D and F) and one cell that acid mucopolysaccharide is only mimbrane that surrounded granule(type-E). The results are follows:The thpe-A fland cell is commonly observed between the two species. The type-A gland cell in Achatina fulica possesses a nucleus with a developed heterdchromatin, and the cytoplasm was filled with round granules. The granules were surrounded with an uncertain boundary mimbrane and confirmed with neutral mucopolysaccharides, but is confirmed acid mucopolysaccharide in Incilaria fruhstorferi.The type-B gland cell is obwerved in the two species, too. The type-B gland cell in Achatina fulica was round shaped, and included an evenly alrge nucleus. The uncleoplasm included granules that were confirmed in the neutral mucopolysaccharides of the two species. The type-C and D gland cells exist only in Incilaria fruhstorferi, nucleoplasm was well developed heterochromatins. The type-E gland cell appears in the acinous surrounded the salivary gland of Incilaria fruhstorferi. Thdse granules appear irregular irregular shape and size and the cytoplasm is formed in alveolar. The type-F gland cells are commonly observed in the salivary glands of the two species. They are similar with the type-B gland cell, but the granular shape is comparatively small and irregular, and possess the neutral mucos granules. The type-H gland cells are mainly seen in only Achatina, and in nucleus is a well developed heterochromatin. The cytoplasm is filled with round small granules with acid mucopolysaccharide for alcianophilia observed. The type-I cell was small cell with an irregular shape and only observed in the gland cells of Achatina fulica. The heterochromatins were developed in the nucleus and the granules are not observed in cytoplasm.Secretory ducts of saliva are composed of the interlobular duct and interlobar secretory duct. In Achatina fulica the interlobular duct consists of a simple cuboidal epithelium, while the endothelium of intralobar secretory duct of Incilaria fruhstorferi consists of a simple squamous epithelium and in the cytoplasm is filled with granules(type-G secretory cell). A SDS-PAGE was carried out to confirm that the protein band pattern consist of salivary gland. In conclusions, five more bands in Achatina fulica and three bands in Incilaria fruhstorferi were confirmed in MW<29 kDa. one main band coincides comparatively with both and is between 29-45 kDa. There are four main bands in Achatina fulica and two main bands in Incilaria fruhstorferi between 45-66.5 kDa respectively. The bands in Achatina fulica seem more complex than in incilaria fruhstorferi.

• Korean Journal of Environment and Ecology
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• v.30 no.1
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• pp.104-109
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• 2016

In Korea, the government has invested the installation of artificial reefs (ARs) which deploying to enhance the restoration of marine environment and productivity on the coastal area at the part of 222,627ha, from 1971 to 2014 for 44 years. The number of ARs are gradually increasing, while their comparison and corelation analysis were not much studied. Therefore, this study is to analyse temporal variation of ARs which composed of concrete named the Horn triangle reefs were deployed at Pohang, Jangkil-ri, a depth of 5 to 7m, in 2003, was monitored 4 times from 2009 to 2011. In results, the biodiversity investigated that the dominant species was Mollusca Omphalius pfeifferi except in 2009. The different species mainly depend on spatial-temporal variation. In this type of study can be used to the R&D, management and government policy of ARs as well improving marine environment.

• Korean journal of applied entomology
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• v.50 no.2
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• pp.83-96
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• 2011

This study was conducted to investigate the influence of natural degrading polymer film covering in rice paddies on the benthic macroinvertebrate community structure in Dangsu-dong, Suwon, Gyeonggi-do from May 2009 to September 2009. We compared 5 treatments: golden apple snail farming (GF), natural degrading polymer film + organic farming (NOF), natural degrading polymer film + chemical farming (NCF), conventional farming (CF), and no fertilization (NF) as the control. The total number of species was highest in NOF followed by GF, NF, NCF, and CF. The total number of individuals was highest in NOF followed by NCF, CF, NF, and GF. The Dominance index (DI) ranged from 0.43 to 0.95. The highest dominance index was in GF followed by NCF, NF=CF, and NOF. The species diversity index (H') for each experimental plot ranged from 0.49 to 2.93. The average species diversity index was highest in NOF followed by NF, GF, CF, and NCF. After the natural degrading polymer film covered the paddies, the benthic macroinvertebrates tended to recover, but leeches and aquatic beetles increased. Mollusca and Annelida, which are sensitive taxa, decreased in both species and individual numbers after the soil was covered with the natural degrading polymer film. The number of species tended to recover. However, the number of individuals continued to decrease.d, especially individuals. Since then, the number of species tended to recover. However, the number of individuals decreased.

• Journal of Food Hygiene and Safety
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• v.13 no.3
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• pp.201-205
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• 1998

In Korea, a small proportion of fishery products are contaminated with a considerable amount of potentially hazardous contaminants. So, there is generally a high risks to consumers. Inorganic contaminants with the greatest potential for toxicity are Sb, As, Cd, Pb, Hg, Se and the Sulfides. As appears to be much more variable than the others. This study was performed to assess the levels of the As in fisheries caught from the waters of the western coast of Korea. The samples included 26 kinds of fishes, 18 kinds of Mollusca, 3 kinds of Crustacea and 7 kinds of salted fishes. The Moisture content of molluscans was significantly higher than that of others (p<0.05). And the As contents of crustaceans were significantly higher than those of fishes, molluscans and salted fishes (p<0.05). The As content of Turban shell was 51.62 ppm, which was the highest among the samples. Also, the As contents of eel, cuttle fish and blue crab were found to be higher than in other fisheries. This variability offers a solution for the reduction of exposure to As through restricting the harvest of aquatic organism from the western coast of Korea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.5
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• pp.288-291
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• 1988

We have veen already reported the distribution of PSP of bivalve mollusca in southern coast of Korea and also analyzed their characteristics. The purpose of this study was to develop detoxification method for PSP infested sea mussel, Mytilus edulis, by rearing methods or processing treatments. There was no significant detoxification effect when the PSP infested sea mussel was reared in a tank with water recirculation system, but the toxicity of sea mussel rapidly decreased during the rearing time in a water flow system with filtered water. The detoxification rate of PSP during the rearing for 5 days in a water flow system tank with $15-17^{\circ}C$ of sea water was $94\%$ in case of high toxic sample with more than $2,600{\mu}g/100g$ and about $40\%$ in case of low toxic sample with less than $100{\mu}g/100g$. The toxicity of PSP extracted from the sample with 0.1N/ HCl solution was about 2-5 times higher than that extracted with distilled water. When sea mussel contained $100-150{\mu}g-PSP$ per 100g of edible meat was boiled for 30 min with tap water, the toxicity was destroyed as the level of PSP undetected by mouse assay. We can suggest that boiling of sea mussel with tap water was one of the most significant detoxification methods, but it was not enough to be safe in case of extremely high intoxicated sea mussel with PSP. For example, the digestive gland of sea mussel contained more than $9593{\mu}g/100g$ was heated in a can with tap water at $116^{\circ}C$ for 65 min. the residual PSP was more than $170{\mu}g$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.5
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• pp.297-302
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• 1988

We have veen already reported the distribution of PSP of bivalve mollusca in southern coast of Korea and also analyzed their characteristics. The purpose of this study was to develop detoxification method for PSP infested sea mussel, Mytilus edulis, by rearing methods or processing treatments. There was no significant detoxification effect when the PSP infested sea mussel was reared in a tank with water recirculation system, but the toxicity of sea mussel rapidly decreased during the rearing time in a water flow system with filtered water. The detoxification rate of PSP during the rearing for 5 days in a water flow system tank with $15-17^{\circ}C$ of sea water was $94\%$ in case of high toxic sample with more than $2,600{\mu}g/100g$ and about $40\%$ in case of low toxic sample with less than $100{\mu}g/100g$. The toxicity of PSP extracted from the sample with 0.1N/ HCl solution was about 2-5 times higher than that extracted with distilled water. When sea mussel contained $100-150{\mu}g-PSP$ per 100g of edible meat was boiled for 30 min with tap water, the toxicity was destroyed as the level of PSP undetected by mouse assay. We can suggest that boiling of sea mussel with tap water was one of the most significant detoxification methods, but it was not enough to be safe in case of extremely high intoxicated sea mussel with PSP. For example, the digestive gland of sea mussel contained more than $9593{\mu}g/100g$ was heated in a can with tap water at $116^{\circ}C$ for 65 min. the residual PSP was more than $170{\mu}g$.