• Atmosphere
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• v.26 no.3
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• pp.357-372
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• 2016

Northeast Asian regions have recently become the main source of anthropogenic and natural aerosols. Measurement of aerosols on the sea in these regions have been rarely conducted since the experimental campaigns such as ACE-ASIA (Asian Pacific Regional Aerosol Characterization Experiment) in 2001. Research vessel observations of aerosol mass and chemical composition were performed on the Yellow and south sea around the Korean peninsula. The ship measurements showed six representative cases such as aerosol event and non-event cases during the study periods. On non-event cases, the anthropogenic chemical and natural soil composition on the Yellow sea were greater than those on the south sea. On aerosol event cases such as haze, haze with dust, and dust, the measured mass concentrations of anthropogenic chemical and element compositions were clearly changed by the events. In particular, methanesulfonate ($MSA^-$, $CH_3SO_3^-$), a main component of natural oceanic aerosol important for sulfur circulation on Earth, was first observed by the vessel in Korea, and its concentration on the Yellow sea was three times that on the south sea during the study period. Sea salt concentration important to chemical composition on the sea is related to wind speed. Coefficients of determination ($R^2$) between wind speed and sea salt concentration were 0.68 in $PM_{10}$ and 0.82 in $PM_{2.5}$. Maximum wave height was not found to be correlated to the sea salt concentration. When sea-salt comes into contact with pollutants, the total sea-salt mass is reduced, i.e., a loss of $Cl^-$ concentration from NaCl, the main chemical composing sea salt, is estimated by reaction with $HNO_3$(gas) and $H_2SO_4$(gas). The $Cl^-$ concentration loss by $SO_4^{2-}$ and $NO_3^-$ more easily increased for $PM_{10}$ compared to $PM_{2.5}$. The results of this study will be applied to verifying a dust-haze forecasting model. In addition, continued vessel measurements of aerosol data will become important to research for climate change studies in the future.

• Ocean Science Journal
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• v.40 no.1
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• pp.55-59
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• 2005

We cloned the complete cDNA of the ${\beta}-bubulin$ from the soft coral, Scleronephthya gracillimum $(K\ddot{u}kenthal)$ (Alcyonacea, Octocorallia, Anthozoa, Cnidaria), via the random sequencing of a cDNA library and the 5'-rapid amplification of cDNA end (RACE) technique. The full-length cDNA of the S. gracillimum ${\beta}-tubulin$ comprised 1541 bp, not including the poly $A^+$ stretch, also contained a complete open reading frame, which codes for a total of 445 amino acids. The amino acid residues 16402 appeared to be in a state of conservation in a variety of animals. Northern blot analysis clearly demonstrated that the sequence we have obtained is, indeed, the full-length cDNA of the ${\beta}-bubulin$ gene in S. gracillimum.

• Atmosphere
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• v.19 no.1
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• pp.67-78
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• 2009

A strong negative correlation has been detected between the North Pacific Oscillation Index (NPI) and the Effective Drought Index (EDI) in May over Korea. In May of positive NPI year, anomalous patterns caused a drought in Korea as follows: the anomalous south-low, north-high low-level pressure patterns in the northeast and southeast of Korea have strengthened the anomalous northerlies to Korea. In addition, these anomalous northerlies have prevented western North Pacific (WNP) high from moving northward. As a result, anomalous descending flows have strengthened in the mid-latitude region in East Asia. In the WNP, the anomalous south-high, north-low sea surface temperature (SST) has been widely distributed, which has strengthened anomalous south-low, north-high low-level pressure patterns. These anomalous characteristics of pressure and SST patterns observed in May of positive NPI years have already been detected in previous winter (December-February) and early spring (March, April). In addition, the anomalous negative sea ice concentration in the North Pacific during two seasons has strengthened the anomalous anticyclonic circulation in the same region and in turn made a contribution to formation of anomalous south-low, north-high pressure patterns in May.

• Atmosphere
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• v.21 no.4
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• pp.439-446
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• 2011

NCEP reanalysis data were analyzed in order to provide distribution of global wind resource and wind speed in the surface layer for the years 2000-2009. Wind speed at 10 m above ground level (AGL) was converted to wind speed at 80 m above the ground level using the power law. The global average 80 m wind speed shows a maximum value of $13ms^{-1}$ at the storm track region. High wind speed over the land exists in Tibet, Mongolia, Central North America, South Africa, Australia, and Argentina. Wind speed over the ocean increased with a large value in the South China Sea, Southeast Asia, East Sea of the Korea. Sea surface wind in Western Europe and Scandinavia are suitable for wind farm with a value of $7-8ms^{-1}$. Areas with great potential for wind farm are also found in Eastern and Western coastal region of North America. Sea surface wind in Southern Hemisphere shows larger values in the high latitude of South America, South Africa and Australia. The distribution of low-resolution reanalysis data represents general potential areas for wind power and can be used to provide information for high-resolution wind resource mapping.

• Environmental Analysis Health and Toxicology
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• v.20 no.4 s.51
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• pp.333-341
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• 2005

In order to know whether polychaetes could be used as an appropriate organism for the detection of genotoxicity, DNA strand breaks were evaluated in blood cells of a nereidae worm (Perinereis aibuhitensis) exposed to various aquatic chemical pollutants (e.g. Cd, Pb, Pyrene, Benaor[a]pyrene). Hydrogen peroxide increased DNA strand breaks up to the highest concentration (10 $\mu$M). Higher concentration than 0.1 $\mu$M showed a significantly more DNA damage than control. Cadmium and lead also showed higher DNA damage than control, over 1.0 and 1 $\mu$g/L, respectively. In case of pyrene, DNA damage was detected even at 0.001 $\mu$g/L. However, DNA damage decreased due to apoptosis at the highest concentration of pyrene and Pb. This study suggested that the polythaetous blood cells could be used effectively for screening genotoxic contaminants in the environment.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.1
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• pp.98-102
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• 2020

We examined the comparative spawning ecology of daggertooth pike conger Mureanesox cinereus and common pike conger M. bagio in the South Sea of Korea from May 2018 to December 2019. In the South Sea of Korea, the mean total length (TL) of M. cinereus was significantly smaller than that of M. bagio. The sex ratios of both species were skewed toward females. The spawning period of M. cinereus was from June to October, while the spawning period of M. bagio was from August to October. The lengths at 50%, 75%, and 97.5% sexual maturity of M. cinereus females were estimated as 54.6 cm, 60.4 cm, and 74.1 cm TL, respectively. It was not possible to estimate lengths at sexual maturity for M. bagio in the South Sea of Korea due to the absence of immature stages.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.5
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• pp.495-499
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• 2003

Age and growth of purpulish Washington clam (Saxidomus purpuratus) was investigated from 480 samples monthly collected from January to December 2002 in Jinhae Bay, Korea. Examination of outer margins of the shell revealed that the translucent zone was formed once a year from March to April, it can be used as annulus. Ages were determined from ring radius of shell, and maximum age of the the clam was 9 years. The spawning period was from May to October, and the main spawning occurred in July. The relationship between shell length (SL) and shell height (SH) was $SH=0.8405{\times}SL^{-4.9709}\;(R^2=0.97)$ and that between the shell length (SL) and total weight (TW) was $TW=0.9580{\times}10-4{\times}SL^{3.220}(R^2=0.97).$ The von Bertalanffy growth equation were $SL_t=125.57(1-e^{-0.2523(t+0.5367)},\;TW_t=549.26(1-e^{-0.2523(t+0.5367)})^{3.220}.$

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.6
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• pp.671-676
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• 2011

To determine the optimum light intensity for mass culture of the brackish-water cyclopoid copepod Paracyclopina nana, survival, growth, and productivity of the copepod were examined at several light intensities (0, 10, 100, 500, 1,000 lx). The survival rate of P. nana from nauplius to adult decreased with increasing light intensity. The highest survival rate was found under the dark condition, with 61.7% surviving; no significant difference was observed between 0 and 10 lx (51.7%) and the lowest survival rate was with 100 lx (26.7%). Survival rates at 500 and 1,000 lx were significantly lower in comparison with other conditions. The developmental period from nauplius to copepodid (5.8 days) and to adult (11.8 days) at 10 lx was significantly shorter than in the other treatments. Daily mean nauplius production of adult females over 7 days at 0, 10 and 100 lx was significantly higher than at 500 and 1,000 lx. In the 1,000 lx treatment, 99% of the adult females died on the $14^{th}$ day. The optimum light intensity for the mass culture of P. nana could be 10 lx, which had no adverse effects on survival, development, or reproduction.

• Animal Systematics, Evolution and Diversity
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• v.8 no.2
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• pp.243-258
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• 1992

For the systematic study of Korean Asteroidea the specimens collected from total 69 localities in the South Sea, Korea during the period from April, 1980 to Apirl, 1992 were indentified. As a result, 23 species, 18 genea, 8 families and 5 orders were identified of which two species, Mediaster brachiatus and Stellaster equestris have not been reported in Korea yet. Asterina perctinifera was the commonest species collected from 43 localities of 69 localities. Fifteen species were found in Korea Strait and Cheju Island area, respectively. Fifteen temperate species, 7 tropical species and 3 boreal species were found to be distributed in the South Sea of Korea. The asteroids known so far in Korea tuned out to be 43 species.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.57 no.4
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• pp.364-371
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• 2024

We studied the age and growth of anchovies Engraulis japonicus, collected using three different fishing gears (drag net, set net, and bottom trawl) in the South Sea of Korea from November 2020 to October 2021.To determine the age, 344 speciemens were analyzed by reading the otolith sagittal plane. Monthly changes in the growth of translucency at the edge and the marginal increment ratio revealed that annuli in otoliths were fully formed in March once a year. We compared four different types of growth equations, and found that the data set of observed length at age (yearly) as estimated the growth parameter (L_∞ = FL 16.17 cm, k = 0.33/year, t₀ = -1.65) fitted well on the von Bertalanffy growth curve.