• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.3 no.3
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• pp.149-157
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• 1998

Seasonal changes of topography, sediment grain size and accumulation rate in the Gomso-Bay tidal flat, west coast of Korea, have been studied in order to understand the seasonal accumulation pattern and preservation potential of the tidal-flat sediments. Seasonal levelings across the tidal flat show that the landward movement of both intertidal sand shoals and cheniers accelerates during the winter and typhoon periods, but it almost stops in summer when mud deposition is instead predominant at the middle and upper tidal flats. Seasonal variations of mean grain size were largest on the upper part of middle tidal flat where summer mud layers were eroded during the winter and typhoon periods. Measurements of accumulation depths from sea floor to basal plate reveal that accumulation rates were seasonally controlled according to the elevation of tidal-flat surface. The upper tidal flat where the accumulation rate of summer was generally higher than that of winter was characterized by a continuous deposition throughout the entire year, whereas in the middle tidal flat, sediment accumulations were concentrated in winter relative to summer and were intermittently eroded by typhoons. The lower tidal flat were deposited mostly in winter and eroded during summer typhoons. Can cores taken across the tidal flat reveal that sand-mud interlayers resulting from such seasonal changes of energy regime are preserved only in the upper part of the deposits and generally replaced by storm layers downcore. Based on above results, it is suggested that the storm deposits by winter storms and typhoons would consist of the major part of the Gomso-Bay sediments.

• Korean Journal of Environmental Biology
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• v.36 no.2
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• pp.107-116
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• 2018

In this study, the distribution of sedimentary environment and benthic macro-fauna in habitats and non-habitats of Zostera marina were investigated. The purpose of this study was to obtain basic data about the sedimentary environment and benthic macro-fauna in the habitats and non-habitats of Z. marina. Sand was dominant within habitat environments, whereas the non-habitats were predominantly composed of silt. As a result, the habitats of Z. marina have a different grain size and organic matter content compared to the non-habitats. These differences in the sedimentary environment were expected to influence the species composition of benthic animals. Benthic communities in the habitats of Z. marina showed a higher density and a greater number of species than in the non-habitats. As a result of an ecological index evaluation, the species diversity index (H') was $3.44{\pm}0.10$ for the habitat; the non-habitat was analyzed as $2.34{\pm}0.35$. It was also found that the stability of community in the habitats was higher than that in the non-habitats. The cluster analysis also clearly showed that habitats and non-habitats of Z. marina have distinct characteristics.

• Journal of The Korean Society of Integrative Medicine
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• v.10 no.4
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• pp.121-136
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• 2022

Purpose : Marine therapy is an activity that promotes public health such as constitution improvement, immunity improvement, and anti-aging by utilizing marine therapeutic resources such as seawater, mud, seaweed, salt and sea climate. In Europe developed countries, the marine therapy industry has been developing for centuries, with France, Germany, and Israel leading the way. Currently, it has achieved great industrial achievements and is of great help in improving the human health. The purpose of this study is to investigate how marine therapeutic resources benefit to human health, as well as how to study and utilize their efficacy. We analyzed previous research articles related to the effects of marine therapeutic resources. Methods : The study included a total of 830 published literatures in the last 20 years from the Republic of Korea and other contries. PubMed and Google Scholar were utilized to collect the foreign source while the local scientific publications were accessed through the Korean Education and research Information Service (KERIS) and Korean studies Information Service System (KISS). The keywords used to search foreign literature were "marine therapy", "Thalassotherapy", "seawater", "deep seawater", "saline groundwater", "sand therapy", "mud therapy", "hydrotherapy", "seaweed", "Sun light", "sea salt", "marine animal", and "marine microorganisms" were combined, and for the domestic literature, the keywords were "marine therapy", "marine therapeutic resources", "seawater", and "sand". Results : A total of 830 research papers were found as a result of searching for domestic and international papers related to marine therapeutic resources. The collected documents were classified into 175 seawater resources, 259 marine mineral resources, 41 marine environment, and 355 marine organisms. The efficacy of each marine therapeutic resources was analyzed. By resources type, there were about 213 papers on the efficacy of seaweed, followed by about 175 papers on seawater, 142 on microorganisms, 124 on mud/peat, and sand, salt, minerals and others are appeared in order (Table 1). Conclusion : Korea has the highest marine biodiversity index, excellent tidal flats, four distinct seasons, and various sea environments of the East sea, Yellow sea, South sea and Jeju sea. For this reason, Korea has a much more diverse marine therapeutic resources than other advanced countries in the marine therapy industry. prebiously, we thought that the sea was only valuable as a shipping port and fishery industry. But now, it been shown that the ocean can become a new industrial field which can contribute to human health and well-being by providing healing and therapy to people through the gift of marine resources.

• Korean Journal of Ecology and Environment
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• v.57 no.2
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• pp.61-74
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• 2024

Daemadeung, located in the estuary of the Nakdong River, is formed by sand dunes and possesses well-developed intertidal flats. This study aimed to investigate the habitat of benthic microalgae, photosynthetic pigments, and photosynthetic efficiency in the intertidal flats of Daemadeung from January to December 2011. The inorganic nitrogen content in the sediment pore water was primarily composed of ammonium, while nitrate + nitrite was dominant in the upper layer water. The concentration of chlorophyll a and fucoxanthin in the sediment surface was significantly higher than the mean of all the sediment layer. The average Fv/Fm of benthic microalgae during the entire survey period was 0.52±0.03, with the highest value (0.61±0.08) observed in February. The rETR_max showed a seasonal trend, being high from spring to early autumn (April to October) and low from winter to early spring (January to March, November, December), with the highest value (153.05±2.30 µmol electrons m^-2 s^-1) in July and the lowest (38.49±5.17 µmol electrons m^-2 s^-1) in January. The average Fv/Fm of diurnal microalgae was 0.48±0.03, with the highest value (0.61±0.08) observed at noon. The rETR_max showed a highest peak at noon (54.24±11.35 µmol electrons m^-2 s^-1) and reached its lowest point at 16:00 (26.17±4.75 µmol electrons m^-2 s^-1). These findings suggest that the productivity of benthic microalgae varies significantly depending on the survey time and sediment depth. Therefore, to quantify the productivity of benthic microalgae using Diving-PAM, surveys should be conducted based on tidal conditions, and simultaneous pigment analysis of sediment layers should also be performed.

• Journal of the Korean association of regional geographers
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• v.19 no.2
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• pp.223-233
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• 2013

Yeonpyeong Island, an island of Ong-jin County, is a very important and meaningful area in terms of its geo-politics and natural environment. But in spite of well preserved natural environment, because of limited access and security risk, there were little researches. In this sense this study would be meaningful for inquiring into the regional geomorphology of Yeon-pyeong Island. The major findings of this study are as follows. 1) 12 sites among 20 sites was evaluated 1st grade, and this means that geomorphic value of Yeon-pyeong Island is very excellent. 2) Coastal landforms of Yeon-pyeong Island are classified three major types which are rocky coast which consist of wave-cut platform and sea cliffs, sand or shingle beaches and coastal plain in the embayment area, and tidal flat areas and small uninhabited islands. 3) Cross sectional shape of Yeon-pyeong Island is asymmetric, since coastal erosion of island concentrate on the northern and western shore. 4) Quality and value of tidal flats will be deteriorate unless the dyke construction is stopped.

• Journal of Wetlands Research
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• v.7 no.2
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• pp.53-67
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• 2005

Cheonsu bay, which is typically a semi-closed type, is characterized by various environments such as channels, sand bars, small islands and tidal flats. The construction of Seosan A and B sea dikes from 1983 to 1985 might continuously change sedimentary environments in the northern part of the bay. In order to investigate sedimentary environment, surface and core sediments were sampled at the Hwangdo tidal flat and adjacent sea in June and October 2003. The surface sediments consisted of five sedimentary facies. Generally, the surface sediments in October were changed coarser on the tidal flat and little changed in the subtidal area compared to those in June 2003. Sedimentary facies analysis of three core sediments suggested that wave and tidal current were relatively strong in the tidal flat near Hwangdo, whereas the energy was relatively low in the tidal flat near channel. Sediment accumulation rates in the Hwangdo tidal flat during 11 months indicated that sediments deposited in the central part, whereas eroded in eastern and western sides of the tidal flat. These caused that sea dike changed tidal current patterns and sediment supplies.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.6
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• pp.1014-1025
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• 2014

We measured the concentrations of various geochemical parameters [grain size, ignition loss (IL), chemical oxygen demand (COD), acid volatile sulfide (AVS), and trace metals (Fe, Cu, Cd, Pb, Cr, Mn, As, Zn, and Hg)] in the surface sediments of two intertidal oyster Crassostrea gigas farming areas (Iwon and Mongsan tidal flats) on the Taean Peninsula, Korea, to evaluate the pollution level of organic matter and trace metals in sediment. The intertidal sediments in the study region comprise mostly sand with a mean grain size of 2.5-3.5 Ø. The concentrations of IL, COD, AVS, and trace metals in the sediment of two study regions were either similar or lower in oyster farming areas relative to non-farming areas, apparently due to biological uptake or physical and biological sediment reworking. Based on the results for the pollution evaluation of organic matter and trace metals derived from sediment quality guidelines, enrichment factor, and geoaccumulation index, our results suggest that the sediment in these two intertidal oyster farming regions is not polluted by organic matter and trace metals.

• Journal of Korea Water Resources Association
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• v.35 no.4 s.129
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• pp.425-442
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• 2002

The land reclamation area of Saemangeum(Kunsan) is located between $126^{\circ}10'\;E{\sim}126^{\circ}50'\;E\;and\;35^{\circ}35'\;N{\sim}36^{\circ}05'\;N$ at the western coast of the Korean peninsula. The reclamation area of Saemangeum has a range of 5.6m spring tide and the maximum tidal current speed is about $1.41m\;s^{-1}$. In ordinary spring tide. Most of the sediments deposited on the tidal flats are transported from the Geum river, the Mankyung river and the Dongjin river. The soil in this area consists of silty sand with the depth of 10m to 30m. The wind in winter is strong from the direction of northwest. Saemangeum coastal area is being constructed 33km the sea dike and 40,100ha reclamation area. The purpose of this study Is to find the residual circulations in four seasons before and after the dike construction by a robust diagnostic and prognostic numerical model.

• Journal of Species Research
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• v.8 no.4
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• pp.319-336
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• 2019

During an investigation of unrecorded prokaryotic species in Republic of Korea, a total of 53 bacterial strains belonging to the class Gammaproteobacteria were isolated from soil, seawater, tidal flats, rhizosphere, salt ponds, beach sand, urine, manure, sediment, and animal intestine (Russian grayling butterfly [Hipparchia autonoe], mouse [Mus musculus], and sea bass [Lateolabrax japonicus]). Strains were identified to species using the 16S rRNA gene sequence, showing high similarity (>98.7%) with the closest bacterial species and forming a robust clade in the neighbor-joining phylogenetic tree. The 53 strains of Gammaproteobacteria in this study have not been report previously in Korea. Therefore, we describe 27 genera of 16 families in 7 orders: 13 strains in the order Alteromonadales, 1 strain in the order Chromatiales, 11 strains in the order Enterobacterales, 7 strains in the order Oceanospirillales, 10 strains in the order Pseudomonadales, 8 strains in the order Vibrionales, and 3 strains in the order Xanthomonadales. Gram reaction, strain ID, isolation source, and morphological and basic biochemical characteristics are described for each species.

• 한국해양학회지
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• v.27 no.4
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• pp.277-289
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• 1992

Kyeonggi Bay, a macrotidal coastal embayment in the Yellow Sea coast of central korea, is fringed by vastly developed tidal flats. About 400 surface sediment samples were collected from the intertidal and subtidal zones of Kyeonggi Bay for a study of the sediment distribution pattern and the surface sediment characteristics of this environment. The kyeonggi Bay surface sediment becomes progressively finer in the shoreward direction, from offshore sand to shoreward silty sand and sandy silt. This shoreward-fining trend is repeated again on the tidal flat and, as a consequence, a grain-size break occurs near the low-water line which separates the intertidal area from the subtidal one. The intertidal and subtidal sediments differ from each other in textural characteristics such as mean grain size and skewness and this can be interpreted to result from differences in hydraulic energy and morphology between the two environments. The mineral and chemical compositions of the Kyeonggi Bay sediments are largely controlled by the sediment grain size. Smectite was nearly absent in the clay mineral assemblage of Kyeonggi Bay sediment. The contents of Co, Cu and Ni were high in the Banweol tidal flat, which suggests a continuous process of accumulation of these metals. the intertidal environment appears to respond rapidly to artificial coastal modifications, the effects of which should be taken into consideration when planning a dam construction or coastal reclamation.