• Journal of Marine Life Science
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• v.6 no.2
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• pp.97-105
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• 2021

Tegillarca granosa, is one of the most important fishery resources throughout Asia. However, due to industrialization factories, marine environmental pollution, and global warming, the marine fishery production has drop sharply. In order to understand the genetic factors of the blood clam, which is a major fishery resource on the southern coast of Korea, the whole genome of blood clam was studied. The assembled genome of T. granosa was 915.4 Mb, and 19 chromosomes were identified. 25,134 genes were identified, and 22,745 genes were functionally annotated. As a result of performing gene gain and loss analysis between the blood clam genome and eight other types of shellfish, it was confirmed that 725 gene groups were expanded, and 479 gene groups were contracted. The homeobox gene cluster of blood clam showed a well-preserved genetic structure within lophotrochozoan ancestor. T. granosa genome showed high similarity between three hemoglobin genes with Scarpharca broughtonii. The blood clam genome will provide information for the genetic and physiological characteristics of blood clam adaptation, evolution, and the development of aquaculture industry.

• Journal of the Korean Society of Earth Science Education
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• v.15 no.1
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• pp.91-102
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• 2022

Sinsu Island in Korea National Marine Park is suitable for geological learning and geotourism as various geological structures, geological activities, and fossils can be observed. In this study, eight geosites were developed by analyzing 2015 revision science curriculum. The 3D panoramic geological virtual field trips were developed according to the three-step outdoor learning model. The 3D panoramic geological virtual field trips, which consist of 8 classes, are composed of cooperative learning by group, enabling autonomous inquiry activities. It is designed to realize convergence education that can learn not only geology but also creativity and humanity through nodular Limestones, exfoliation, salt weathering, perforated shell holes, sedimentary structures and environments, dinosaurs habitats, and volcanic activity. Five experts revised and supplemented the Delphi analysis method to verify the validity of the development purpose and direction. The satisfaction with the geological field for Sinsu Island course was 4.52, indicating that the overall satisfaction with the field course was high. By reflecting on the opinions of each student and reinforcing safety education, we completed the 3D panoramic geological virtual field trips for Sinsu Island. The 3D panoramic geological virtual field trips in Sinsu Island in Korea National Marine Park will be a good example of geology learning tourism where you can make memories and enjoy while studying geology.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.6
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• pp.880-889
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• 2021

The home meal replacement (HMR) market has attracted significant attention due to COVID-19 pandemic and products that utilize the combination of different processed ingredients are now being developed. In this study, Broughton's ribbed ark Scapharca broughtonii was soaked in seasoned soy sauce with the incorporation of mustard leaf Brassica juncea (M-BRA), which is known to have a unique texture as well as excellent functional properties such as antioxidation, to develop a regional specialty product. The optimal conditions for manufacturing M-BRA from the seasoned soy sauce (the sauce to be added [X₁] and the soaking time [X₂]), were examined using response surface methodology (RSM) to analyze the significance of the salinity (Y₁), amino-N content (Y₂), and overall acceptance (Y₃). The coefficient of determination (R²) between X₁-X₂ and Y₁-Y₃ were close to 1, thereby confirming the suitability of the RSM model. The optimal conditions were seasoned soy sauce addition of 140% and soaking time of 156 min. The M-BRA manufactured under these conditions exhibited superior overall acceptance compared to seasoned commercial soy sauce, which was used as a control. We expect that the market for M-BRA manufactured by combining marine and agricultural materials will expand owing to superior overall acceptance compared with commercial products.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.6
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• pp.869-879
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• 2021

Methods for the development of home meal replacement seafood tailored to consumer needs for the advanced use of Broughton's ribbed ark Scapharca broughtonii (BRA) in Korea are required. In this study, we developed a cheese-topped, semi-dried, and seasoned Broughton's ribbed ark (S-BRA) tailored for the younger generation with an improved texture and fish odor. The optimization of conditions to improve the texture and fish odor was performed using RSM. The design of the model was appropriate because there was no significant difference (P>0.05) between the predicted and actual values of moisture content, hardness, and overall acceptance, and the optimal preparation conditions were a vinegar content of 2.68%, a soaking time of 62 min, a drying temperature of 60℃, and a time of 162 min. The S-BRA manufactured under these optimal conditions exhibited a lower odor intensity compared to the unsoaked and undried control, suggesting that the fish odor of S-BRA has been improved. The moisture content related to the texture of the S-BRA was lower than that of the control, and the hardness was higher. Therefore, the S-BRA developed in this study will appeal to people of all ages, especially the younger generation; their consumption is expected to increase.

• Journal of Life Science
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• v.31 no.4
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• pp.442-451
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• 2021

Microplastics are fragments of any type of plastic with a size less than 5 mm. Ocean pollution by microplastics is now a worldwide concern in relation to marine ecosystems and human health. The widespread contamination by microplastics means that they can be ingested by and accumulated in diverse species of wildlife, such as fish, mussels, oysters, clams, and scallops. Once ingested, the microplastics can be observed in the intestines, liver, and kidney, and even in the brain. Seafood is one of the major sources of protein intake in humans; therefore, seafood consumption could be pathway for human microplastics exposure. Accumulating evidence indicates that repeated oral exposure to microplastics induces pathologic and functional changes in the reproductive, cardiac, gastrointestinal, endocrine, and even nervous systems of rodents. Maternal exposure to microplastics during gestation and lactation alters metabolic homeostasis in the offspring. Given that seafood provides more than 20% of the total protein intake by over 310 million people worldwide, a reasonable assumption is that microplastics could be substantially accumulated in the human body and impair physiological function. In this review, we have summarized the current status of microplastics contamination in the ocean, their accumulation and toxicities in marine animals and rodents, their exposure to humans, and their potential impacts on human health.

• Journal of the Korean Geotechnical Society
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• v.23 no.6
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• pp.103-114
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• 2007

Sands distributed in Jeju island's coastal areas, Korea, can be classified as silicate sand derived from volcanic rock, carbonate sand derived from shells, and mixed sands containing both silicate and carbonate sands. These three types of sands typically exist in Jeju coastal areas. Samples of silicate, carbonate and mixed sands were obtained from Samyang beach, Gimnyeong beach, and Jeju harbor area, respectively. Compression tests were conducted to assess the compression characteristics of these sands. As a result of these tests, each sand showed different behaviors. For Samyang beach sand, it appeared that initial compression is a larger than the other two sands. For Cimnyeong and Jeju harbor sands, however, the additional compression occurred after initial compression. This could result from the crushing, shattering, and rearrangement of sand particles. In addition, settlement behavior of Jeju harbor ground according to the construction stages was analyzed using the measured data. It showed that in addition to the initial elastic compression, a considerable additional compression occurred with time. The settlements of Jeju harbor ground were predicted by using the elastic settlement calculation methods (empirical methods) and the compression test method. The empirical methods, which did not consider the crushing, shattering, and rearrangement of particles could show smaller result than that occurring actually.

• Korean Journal of Environmental Biology
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• v.28 no.4
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• pp.179-187
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• 2010

The Theory of Island Biogeography describes that the number of species on an island affected by island area and distance from the mainland. This study was performed to compare and analyze the community structure of the macro-invertebrates in three isolated islands, around Korean waters in terms of the Theory of Island Biogeography. Macrobenthic animals were collected using a modified underwater quadrat in August 2009. A total of 104 macrobenthic species were sampled with a mean density of 399 individuals $m^{-2}$ and biomass of 1,506.70 g $m^{-2}$. Based on the abundance and biomass data, there were 10 dominant species accounting for approximately 67.17% of total individuals. The highest densities were found in the amphipoda Amphipoda spp., the bivalvia Modiolus agripetus and Mytilus coruscus, the Sipunculida Phascolosoma scolops and the polychaeta Syllidae unid.. On the contrary, the top ten species made up 95.66% of the total biomass while the three most abundant, the bivalves M. coruscus, Streostria circumpicta and M. agripetus. The conventional multi-variate statistics (cluster analysis and non-metric multi-dimensional scaling) applied to assess spatial variation in macrobenthic assemblages. Cluster analysis and nMDS ordination analysis based on the Bray-Curtis similarity identified 2 station groups. The group 1 was consisted with Gageodo (except for lower station at Transect 2) and Dokdo station and was numerically dominated by the polychaetes Eunice antennata and Syllidae unid., the cirripedia Megabalanus rosa and the bivalvia M. coruscus. However, group 2 was associated with Sohwado station and was characterized by high abundance of the anomura Petrolisthes japonicus, the gastropoda Lirularia pygmaea and the brachiopoda Coptothyris grayi. In conclusion, these results suggested that the species diversity and community structure of macrobenthos in three isolated island seemed slightly related to island area and distance from the mainland.

• Korean Journal of Environmental Agriculture
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• v.25 no.1
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• pp.47-57
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• 2006

This study was carried out to select the Eco-tree for successful phytoremediation of abandoned metalliferous mines. We examined vegetation and heavy metal concentrations of woody plants in abandoned mining areas, and also conducted seed germination and seedling growth experiment on contaminated soils from Gahak and Geumjeong mines. Pinus densiflora, Robinia pseudoacacia, Lespedeza bicolor and Alnus japonica showed high frequency in the survey areas and had high heavy metal concentrations compared to other species. Heavy metal concentrations were higher in roots than in leaves and stems. The seed germination rate was in the order of P. densiflora, L. bicolor, R. pseudoacacia, and Alnus japonica from the incubactor and greenhouse experiment. In the incubator experiment germination rate was highest in the control soil for P. densiflora and A. japonica. Germination rate of P. densiflora was highest on the 100% contaminated soil for Gahak mine while germination rate decreased with increased percentage of contaminated soil for Geumjeong mine. In the greenhouse experiment germination rate was lowest on the 40% contaminated soil for Gahak mine while germination rate was lowest on the 20% contaminated soil for Geumjeong mine and increased with increased percentage of contaminated soil. Shoot growth was highest for L. bicolor while root growth was highest for R. pseudoacacia except for 20% contaminated soil in Geumjeong mine.

• Korean Journal of Environmental Agriculture
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• v.29 no.2
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• pp.206-213
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• 2010

The aim of this study was to provide basic informations for restoring a habitat of Nannophy pygmaea Rambur. Environments and flora of the habitats were investigated in Youngdong, Sanbuk, and Nongam South Korea. The habitats were abandoned paddy fields with tree-unshaded space and with the water depths of about 2 - 10 cm all the year round. The water quality was recorded 5.44 - 7.33 in pH, 0.017 - 0.480 dS/m in EC, 1.34 - 4.94 mg/L in T-N and 0.06 - 0.46 mg/L in T-P. The pH and EC showed a wide range values, and T-N and T-P showed a high values comparatively. This result implies that a water quality does not important as the condition for a habitat of the species. A total of 86 vascular plant taxa belonging to 35 families, 60 genera, 67 species, 2 subspecies, 14 varieties and 3 forma were recognized in the habitats. Twenty two species (25.6%) overlapped among the habitats; Equisetum arvense, Salix koreensis, Persicaria thunbergii, Stellaria alsine var. undulata, Hypericum laxum, Kummerowia striata, Epilobium pyrricholophum, Oenanthe javanica, Mosla dianthera, Utricularia vulgaris var. japonica, Plantago asiatica, Eupatorium lindleyanum, Juncus diastrophanthus, J. effusus var. decipiens, J. papillosus, Aneilema keisak, Alopecurus aequalis, Arthraxon hispidus, Carex dickinsii, Cyperus sanguinolentus, Eleocharis acicularis for. longiseta and E. congesta. Biological type was determined to be HH-R5-D4-e(t) type; HH 39 taxa (45.3%), R5 42 taxa (48.8%), D4 59 taxa (68.6%) and e (or t) 23 taxa (26.7%).

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.6
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• pp.694-707
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• 2016

This study investigated the community structure of macrobenthic assemblages in the Taehwa River Estuary, Ulsan, Korea. Macrobenthos were collected with a Van Veen Grab Sampler during February and November 2012. The total species number and mean density were $176species/9.6m^2$ and $1,992inds./m^2$, respectively. Polychaetes were the most dominant faunal group in terms of species (91 species) and abundance ($1,463inds./m^2$). The major dominant species were polychaetes Minuspio japonica ($609{\pm}1,221inds./m^2$), Hediste japonica ($174{\pm}318inds./m^2$), Tharyx sp.1 ($106{\pm}283inds/m^2$), Lumbrineris longifolia ($79{\pm}207inds./m^2$), bivalve Theora fragilis ($114{\pm}272inds./m^2$) and amphipod Grandidierella japonica ($88{\pm}223inds./m^2$). Based on community statistics (cluster analysis and non-metric multidimensional scaling (nMDS) ordination), the macrobenthic community was divided into three station groups. Group I(freshwater dominated stations 2-6 with coarse sediment) was characterized by a high abundance of polychaetes Minuspio japonica, Hediste japonica, Capitella capitata, Pseudopolydora kempi, amphipods Grandidierella japonica and Apocorophium acutum. Group II (ecotone, stations 7-9 with mixed sediment) was numerically dominated by bivalve Theora fragilis, polychaetes Cirriformia tentaculata, Tharyx sp.1, Lumbrineris longifolia and Chaetozone sp. Finally, Group III (seawater dominated stations 10-12 with fine sediment) was characterized by a high density of polychaete Magelona japonica. These results showed that changes in salinity gradient and sedimentary characteristics were the main factors behind spatial changes in the macrobenthic communities of the Taehwa River Estuary.