• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.6
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• pp.402-408
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• 2002

Rice cultivar 'Janganbyeo' was cultivated by irrigating the saline waters of high salinity (3.0%) and medium saliniy (1.5%) for 4 days, and low salinity (0.5%) for 30 days at tillering, early meiosis and heading stage. Leaf injury due to salinity was most severe at tillering stage in 1999, but at heading stage in 2000. Heading date was delayed by 1 to 5 days by treatment of saline waters only at tillering stage. Culm length and panicle length were most severely shortened by treatment at early meiosis stage. Yield and yield components except for panicle number were decreased most by high salinity treatment regardless of growth stages. In particular, ripening ratio and grain weight among the yield components were decreased most conspicuously by the saline water treatment regardless of salinity and growth stage. Regarding grain weight grain-filling rate and duration, there is no remarked difference among the concentrations and treatment durations of saline water at tillering stage. However, their reductions were very different among the concentrations and treatment durations of saline water at early meiosis stage, being greatest when treated with high salinity for 4 days and followed by low salinity for 30 days. Also their reductions were very severe only when treated with high salinity for 4 days at heading stage.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.3
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• pp.52-62
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• 2008

By analyzing specific plant distributions and physicochemical characteristics of topsoil in a reclaimed dredging area, baseline data was found of natural landscape planting sites, and developing dredged fill ground. The reclaimed dredging area is five different stands (1, 2, 3, 4 and 5) which were examined in this research. They are located from sea level to 15 meters in altitude and exhibited typical characteristics of the salt marsh in Gwangyang Bay. Species with high constancy in the vegetation on the reclaimed soil were classified into four stages. A total of 12, 15, 22, 27 and 35 different plant species were found and also increased in stands 1, 2, 3, 4 and 5, respectively. Moving from stand 1 to 5, halophytes decreased and non-halophytes increased. Desalination at each stage of the reclaimed dredging area was a driving force affecting the performance and distribution of halophytes and non-halophytes. Overall, 35 quadrats of soil were selected and analyzed for specific physicochemical characteristics of topsoil between O${\sim}$20cm. Results of the physicochemical analysis such as altitude, slope, vegetation and kind of reclaimed dredging soil, exhibited irregular increases or decreases. As survey areas moved from stand 1 to 4, desalination areas, soil acidity, electric conductions, content of salinity, available phosphorus, potassium, chlorine, calcium, and magnesium indicated decreasing patterns; however, total nitrogen, silt, and clay content increased. Cluster analysis and PCA by environmental data within the stands clearly showed five distinct vegetation patterns on the tested reclaimed area. These results indicate that the differences of performance and distribution of vegetation are due to the SAR in the reclaimed soil and related to the natural survival strategy at the given hostile habitat.

• Atmosphere
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• v.22 no.1
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• pp.97-107
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• 2012

To investigate variation of aerosol number concentration at each different size with three-dimensional (3D) wind components in ocean area, aerosol particles and 3D wind components were measured in the Ieodo Ocean Research Station, which is located to 419 km southwest from Marado, the southernmost island of Korea, from 25 June to 8 July 2010. The Laser Particle Counter (LPC) and ultrasonic anemometer were used to measure the size of aerosol particles and 3D wind components (zonal (u), meridional (v), and vertical (w) wind) respectively. Surface weather chart, NCEP/NCAR reanalysis data and sounding data were used to analyze the synoptic condition. The distribution of aerosol number concentration had a large variation from bigger particles more than 1.0 ${\mu}m$ in diameter by wind direction during precipitation. In the number concentration of aerosol particles with respect to the weather conditions, particles larger than 1.0 ${\mu}m$ in size were decreased and sustained to the similar concentration at smaller particles during precipitation. The increase in aerosol number concentration was due to the sea-salt particles which was suspended by southwesterly and upward winds. In addition, the aerosol number concentration with vertical wind flow could be related with the occurrence and increasing mechanism of aerosol in marine boundary layer.

• Journal of Species Research
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• v.6 no.2
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• pp.101-118
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• 2017

In an investigation of indigenous prokaryotic species in Korea, a total of 57 bacterial strains assigned to the classes Betaproteobacteria and Gammaproteobacteria were isolated from diverse environments. Samples were collected from fresh water, natural caves, soil, paddy fields, lakes, sea water, jeotgal (fermented seafood), salt flats, soil from abandoned mines, plant roots, digestive organs of both Japanese crested ibis (Nipponia nippon) and Burmese python (Python molurus bivittatus) and tidal flats. From the high 16S rRNA gene sequence similarity (>98.7%) and formation of robust phylogenetic clades with closely related species, it was determined that each strain belonged to an independent and predefined bacterial species within either the Betaproteobacteria or Gammaproteobacteria. There is no official report or publication that describes these 57 proteobacterial species in Korea. Overall, in the class Betaproteobacteria there were 16 species in 12 genera of 4 families in the order Burkholderiales and two species in two genera of one family in the order Neisseriales. Within the class Gammaproteobacteia, there were five species in four genera of four families in the order Alteromonadales, 12 species in 11 genera of one family in the order Enterobacteriales, four species in four genera of three families in the order Oceanospirillales, 11 species in four genera of two families in the order Pseudomonadales, two species in the order Vibrionales and five species in five genera of one family in the order Xanthomonadales. Gram reaction, colony and cell morphology, basic biochemical characteristics, isolation source and strain IDs are described in the species description section.

• Journal of the Korean Geographical Society
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• v.47 no.2
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• pp.193-207
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• 2012

This study discussed characteristics of Shindu Coastal Dune as habitat, and relationship between geodiversity and biodiversity. It was identified spatio-temporal variation of incoming nutrients depended on geomorphic differences of foredunes. The main incoming path of nutrients into coastal dune was considered as influx with movement of wind blown sands from the beach and tidal f lat. Concentrations of Na, Mg, K, Ca, and P in blown sands were compared. Concentrations of Na, Mg, and K showed high and irregular pattern in favorable condition of influx of blown sand. So these nutrients were related with geomorphic characteristics of foredunes. However, Na was also influenced by other factor such as salt spray. P was independent from effects of sea water and blown sands. In the case of Ca, a large coastal dune system rather than localized forms of foredunes made differences in the variation. Due to differences in spatio-temporal variation of nutrients, patterns of major vegetation could be inferred to appear differently. This study shows geomorphic dynamics of coastal dunes as habitat, and will provide information for coastal dune management and for understanding biological distribution and growth pattern in coastal dune.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.1 no.2
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• pp.87-96
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• 1968

As the raw material of fish paste, the experiment on shark meats was conducted from July to December 1967 at the Fisheries Research and Development Agency, Pusan, Korea. The result and the conclusion obtained by the experiment are as follows. 1. Much salt-soluble protein was found in the shark meat comparing with to the other fish. 2. Deodorization of shark meat, using less than $0.05\%$ of acetic acid was most preferable for the elasticity and flexibility of its product. 3. Keeping raw material at low temperature was necessary in maintaining its elasticity. 4. In setting shark fish paste, keeping the raw material at $35-40^{\circ}C$ for 40-70 minutes was the most desirable condition. 5. The best temperature and the duration of heating were 40-60 minutes at $89-90^{\circ}C$, Meanwhile, heating at high temperature was preferable for the storage for a long period, but the elasticity and quality has decreased a little accordingly. 6. For the increase of its palatability, adding $30\%$ of yellow corvenia meat or $20\%$ sea eel meat were more preferable. 7. Pre ervation of the product for 20 days at $20^{\circ}C$ or 50 days at $5^{\circ}C$ was possible by adding $0.2\%$ potassium sorbinate to the product as antiseptic.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.10 no.1
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• pp.56-68
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• 2005

We measured nitrate and other nutrients in sediment pore waters retrieved from three sites at the southern upper-tidal flats of the Ganghwa Island. Denitrification rate is estimated by applying a simple 1-D model to the nitrate profiles. Results from Jangwha and Dongmak sites are $7.8{\sim}9.4{\times}10^{-7}{\mu}mol{\cdot}cm^{-2}{\cdot}sec^{-1}$, and $1.4{\sim}3.6{\times}10^{-7}{\mu}mol{\cdot}cm^{-2}{\cdot}sec^{-1}$, respectively. Rates are comparable to those reported around the world in an order of magnitude. Denitrification was lower in summer. The rates were about 1.5 times higher at site where the surface sediments consist of relatively coarser particles. This implies that particle size would control the reactant supply to the subsurface sediment. One may claim the denitrification as an evidence of the biogeochemical purification function of tidal flat. However, the purification seems not a general attribute of a tidal flat when whole system is scrutinized by a thermodynamic criterion. Currently the term 'tidal flat' is used when describing the diverse coastal wetlands such as salt marshes, sandy tidal flats and muddy tidal flats, which exhibit quite different ecological functions. Thus it is worthy of mentioning that the classification of coastal wetlands on the basis of sedimentological characteristics and biogeochemical functions should facilitate our understanding.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.2 no.2
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• pp.78-86
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• 1997

To clarify the phytoplankton blooms in Lake Shihwa after the construction of a dyke, a study on the environmental factors, the distribution of chlorophyll-a, phytoplankton standing stocks, dominant species and primary productivity was carried out in Lake Shihwa and adjacent coastal areas from October, 1995 to August, 1996. Lake Shihwa is brackish water with mixing of freshwater from tributaries and the remaining salt water at the bottom. The dense phytoplankton bloom of average value of 168.6 ${\mu}gChl-a\;l^{-1}$ have occurred throughout the year in Lake Shihwa which is eutrophicated by the large input of nutrients from inflowing 5 tributaries and Shihwa Industrial Complex. The major organisms of algal bloom in Lake Shihwa were diatoms, Cyclotella atomus, Nitzschia sp. and Chaetoceros sp. in autumn and winter, and dinoflagellate Prorocentrum minimum and Chrysophyceae in spring and summer. The autumn and winter diatom blooms were limited by the depletion of silicate in the lake. Diatom blooms have occurred in the coastal areas adjacent to Shihwa lake from winter to summer due to the inflow of nutrient rich-water from Lake Shihwa. The primary productivities in the Lake Shihwa ranged from 2,653 mgC $m^{-2}\;day^{-1}$ to 9,505 mgC $m^{-2}\;day^{-1}$ with an average of 3,972 mgC $m^{-2}\;day^{-1}$. However, most of the high primary production was limited to the shallow euphotic zone due to the inhibition of light penetration. The primary productivities during autumn and winter were limited by the depletion of silicate. Lack of photosynthesis and the decomposition of falling organic matter under the middle of water column accelerated the depletion of dissolved oxygen in the bottom layer.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.9 no.4
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• pp.196-203
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• 2004

To understand the geochemical processes in the Han River Estuary, distributions and behaviors of nutrients, dissolved organic matters, and uranium were investigated and analyzed during estuarine tidal mixing in June 2000 and February 2001. The distribution of inorganic nutrients showed very dynamic distributional patterns implying an apparent nitrification process and a concave non-conservative mixing along the salinity gradient. Dissolved organic carbon was high in the upstream region and decreased sharply in the low salinity region of around 5 psu. The 3-D fluorescence characteristic of dissolved organic matter showed two distinct fluorophores in the study area. Biomacromolecules originated mainly from the indigenous biochemical processes and geomacromolecules from terrestrial humic materials. In the study area, the distribution of geomacromolecule showed a concave non-conservative property along the salinity gradient presumably due to the flocculation and removal processes in the estuary. Meanwhile, distribution of the dissolved uranium, mainly in the form of stable uranium carbonate complex, also showed a concave non-conservative property along the salinity gradient in the Han River Estuary. From this study, the removal rate of dissolved uranium in the Han River Estuary was estimated to be about 7.1 ton per year.

• Journal of the Korea Concrete Institute
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• v.24 no.5
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• pp.553-558
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• 2012

Airborne chlorides are transported to inland by sea wind to be attached to seashore concrete structure surface then penetrated into concrete structure members. Since the surface attached chloride amount are dependent on the amount of airborne chlorides, the prediction of distribution of airborne chlorides is important information in preventing chloride corrosion problems in seashore concrete structures. The prediction of surface chloride amount from airborne chlorides environment is extremely difficult than concrete directly in contact with seawater. In addition, their penetrating tendency is different from that of concrete immersed in seawater. In this study, properties of surface and penetrated chlorides under airborne chlorides environment are investigated. Concrete specimens were manufactured and exposed to marine environment for 3 years. The specimens were analyzed at the time durations of 1, 2, and 3 years to check surface chloride amount to penetrated chloride depth. The results revealed that there were certain differences according to surface roughness of concrete and with and without washing effect due to rainfalls. The evaluation results showed that penetrated chlorides depend on amount of airborne chlorides and duration of exposure. In addition, a notable tendency of having deeper chloride penetration and higher chloride content in concrete members under long-term exposure was observed.