• 수산해양교육연구
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• 제25권5호
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• pp.1205-1213
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• 2013

We investigated the optimum salinity and temperature conditions for the mass culture of small rotifer, Keratella sp.. In the salinity experiment ranging from 0-34‰, the population growth of Keratella sp. drastically increased continuously up to 15‰, and then slightly increased over 20‰. Their maximum density reached 1,007 inds./mL at 0‰. A pre-reproductive phase was shorter in low salinity than in high salinity. The highest number of offspring per female (10.2 inds.) and lifespan of the female (10.7 days) were obtained at 0‰, but there were no significant differences compared to those at 5‰. In the temperature experiments ranging from 16-$32^{\circ}C$, the highest maximum density (1,766 inds./mL) was shown at $24^{\circ}C$. The number of offspring per female significantly increased with increasing temperature, and the highest number of offspring per female was 10.4 inds. at $24^{\circ}C$. The lifespan of female increased with decreasing temperature and the longest lifespan was 12.8 days at $16^{\circ}C$.

• 한국환경과학회지
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• 제28권7호
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• pp.607-615
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• 2019

The purpose of this study is to biological treatment of high salinity wastewater using Aerobic Granular Sludge (AGS). In laboratory scale's experiments research was performed using a sequencing batch reactor, and evaluation of the denitrification reaction in accordance with the injection condition of salinity concentration, surface properties of microorganisms, and sludge precipitability was performed. The results showed that the salinity concentration increased up to 1.5%, and there was no significant difference in the nitrogen removal efficiency; however, it showed a tendency to decrease gradually from 2.0% onward. The specific denitrification rate (SDNR) was 0.052 - 0.134 mg $NO_3{^-}-N/mg$ MLVSS (mixed liquor volatile suspended solid)${\cdot}day$. The MLVSS/MLSS (mixed liquor suspended solid) ratio decreased to 76.2%, and sludge volume index ($SVI_{30}$) was finally lowered to 57 mL/g. Using an optical microscope, it was also observed that the initial size of the sludge was 0.2 mm, and finally it was formed to 0.8-1.0 mm. Therefore, salinity injection provides favorable conditions for the formation of an AGS, and it was possible to maintain stable granular sludge during long-term operation of the biological treatment system.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.316-316
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• 2017

The objective of this study is to estimate quantitatively soil salinity and soil loss at upland soils in agriculture land region in Saemangeum reclaimed land on the south Korea coasts. Soil loss and soil salinity are the most critical problem at reclaimed tidal saline soil in Korea. The several thematic maps of research area such as land cover map, topographic and soil maps, together with tabular precipitation data used for soil erosion and soil salinity calculation. Meteorological data were measured directly as air temperature, wind speed, solar radiation, and precipitation. The experiment was conducted 2% sloped lysimeter ($5.0m{\times}20.0m$) with 14 treatments and it were separated by low salinity division (LSD) and high salinity division (HSD) install. The cation content in ground water increased during time course, but in the case of land surface water the content was variable, and $K^+$ was lower than that of $Na^+$ and $Mg^{2+}$. At the LSD under rainproof condition, the salinity was directly proportional to soil water content, but at the HSD the tendency was no reversed. In condition of rainproof, the amount of soil salinity was higher at the HSD than at the LSD. Positive correlation was obtained between the soil water content and available phosphorous content at the rainfall division, but there was no significance at the surface soil of the rainproof division. Sodium adsorption ratio and anion contents in soil were repressed in the order of vinyl-mulching > non-mulching > bare field. According to the result of analyzing soil loss, soil loss occurred in a vinyl-mulching, a non-mulching and a bare field in size order, and also approximately 11.2 ton/ha soil loss happened on the reclaimed land area. The average soil loss amount by the unit area takes place in a non-mulching and bare field a lot. Our results indicate that soluble salt control and soil erosion are critical at reclaimed tidal saline soil and the results can provide some useful information for deciding management plans to reduce soil loss and salt damage for stable crop production and diverse utilization or cultivation could be one of the management options to alleviate salt damage at reclaimed tidal saline soil in Korea.

• 한국수산과학회지
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• 제12권4호
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• pp.293-296
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• 1979

굴(Crassostrea gigas)의 질소배설과 산소소비에 미치는 수온 및 염분의 상호영향을 조사한 결과는 다음과 같다. 1. 굴은 수온과 염분변화에 따라 질소배설율과 배설암모니아 및 아미노산간의 배설비에 현저한 변동을 보였으며 산소소비량에도 역시 많은 변동을 보였다. 2. 질소배설율과 산소소비율은 염분이 증가함에 따라 특히 고염분일 때 고수온$(29^{\circ}C)$의 경우에 현저히 감소하였으나 저온분에서는 상당히 증가하였다. 이것은 생리적 내성의 고온단계와 저염분에 대한 포상작용에 기인한 결과라고 생가된다. 3. 암모니아를 주로 배설하였으나 상당한 량의 아미노-질소도 배설하였으며, 특히 상염분-온난온도대$(32.5\%_{\circ}-22^{\circ}C$에서는 아미노산의 배설량이 우세하였다. 그리고 어느 실험온도에서나 고염분에서 아미노-질소의 배설량은 감소하였고 저염분에서는 증가하였다. 4. 배설암모니아-질소에 대한 소비산소의 원자비 (O: N비)는 저온$(15^{\circ}C)$에서는 현저히 낮고 상온 및 고온($22^{\circ}$ 및 $29^{\circ}C$)에서는 높았다. 그러나 저온분의 경우 고온에서는 현저히 감소되었다.

• 한국수자원학회논문집
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• 제47권3호
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• pp.297-306
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• 2014

본 연구에서는 해수유입과 강우유출에 따른 용원수로 내의 염분도 분포를 모의하기 위해 EFDC (Environmental Fluid Dynamics Code) 모형을 이용하였다. 유량경계조건은 대표 방류구에서 유출되는 양을 모니터링하여 면적비 유량법으로 산정하였으며, 수위경계조건으로는 시간별 조위 값을 입력하였다. 강우량에 따른 염분도 모의 결과는 일 강우량 245 mm의 유출조건을 반영하였으며, 그 결과 Site 1~2 지점과 망산도 부근 방류구가 위치한 곳에서는 염분도가 0 ppt에 가까운 수치가 나타났으며, 반면 비강우시에는 30 ppt가 넘는 것으로 나타났다. 용원수로 내측지점(Site 2~5)에서의 2010년 1월 1일~12월 31일까지의 염분도 시계열 변화 모의결과와 월별 실측값을 비교하여 나타내었다. 용원수로의 지점별 염분도를 분석한 결과, 내측지점(Site 1~4)과 송정천지점(Site 7~8)에서 염분도가 낮게 나타났다. 이러한 결과를 바탕으로 망산도 부근 염분도를 집중적으로 조사한 결과, 1차 조사결과 누적강우량은 17 mm로 염분도 농도는 21.9~28.8 ppt로 측정되었으며, 2차 조사결과 누적강우 량은 160.5 mm로 염분도 농도는 2.33~8.05 ppt로 나타났다. 결과적으로 용원수로에서는 해수의 순환이 원활하게 이루어지지 않으므로, 이로 인하여 염분도의 차이가 크게 나타났으며 특히 강우시에는 염분도가 급격히 낮아지는 것으로 나타났다.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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• pp.556-564
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• 1993

The response of salt affected rice soils to salinity reclaimation by flushings and chemical amelioration by lime and gypsum were evaluated . Soils with good drainage system responded well to simple reclimation . The effects of seawater intrusion were reduced efficiently in a very short time. Yields of rice crops recovered to their potential level within one to two seasons of cropping. Soil profile strength was also improved under well drained areas. However, when drainage system was ineffective the problems of salinity and soil strength remained unsolved. Under both condition, water depth management played important role in the survival of rice crop under the sline soil conditions.

• Journal of Microbiology and Biotechnology
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• 제20권11호
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• pp.1506-1512
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• 2010

The present study examined the salinity-induced oxidative damage and differential response of enzymatic and nonenzymatic antioxidants of Nostoc muscorum. As compared with carotenoid content that showed induction, the chlorophyll and phycocyanin contents were inhibited after salt stress. Acceleration of lipid peroxidation and peroxide production suggested the onset of oxidative damage. The activities of all studied enzymatic antioxidants were significantly increased by salt stress, with maximum induction occuring with superoxide dismutase (154.8% at 200 mM NaCl treatment). Interestingly, under severe stress condition (250 mM NaCl), ascorbate peroxidase seemed to be more crucial than catalase for peroxide scavenging. Among the studied nonenzymatic antioxidants, ${\alpha}$-tocopherol was induced maximally (56.0%); however, ascorbate and reduced glutathione were increased by only 8.9% after 250 mM NaCl treatment as compared with control cells. Therefore, salinity was found to induce the antioxidative defense system of N. muscorum.

• 한국작물학회지
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• 제43권1호
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• pp.11-14
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• 1998

This study was conducted to find out a desirable screening condition for the salinity tolerance in germination of rice. Seeds of 33 rice varieties were tested in NaCl solutions with various concentration levels. The germination percentage had a decreasing tendency with increasing NaCl concentration and inhibition concentration of 50% germination was 320mM. Standard deviation of germination percentage was highest (28.6) under 300mM NaCl. There was a highly significant correlation between the 50% germination concentration and the germination percentage at 20th day after seeding in 300mM NaCl. Also in 300mM NaCl, the germination percentage at 20th day after seeding was significantly correlated with the germination percentage at the 6th day after seeding. The salinity tolerance on the basis of germination percentage at 6th day after seeding in 300mM NaCl, was strong in 'Hyangnambyeo', 'Ilmibyeo', 'Kancheogbyeo', and 'Namwonbyeo', while weak in 'Ansanbyeo', 'Odaebyeo', 'Nonganbyeo', 'Dasanbyeo', and 'Namcheonbyeo'.

• 수산해양기술연구
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• 제24권4호
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• pp.150-157
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• 1988

여수연해 정치망 어장의 6월, 7월, 8월의 해황변화에 따른 어황관계를 조사하고 분석한 결과는 다음과 같다. 1) 하천수의 유입이 많은 내해와 돌산연안의 정치망 어장에서는 고온.저염분수가 분포하고 외해에는 저온 고염분수가 분포한다. 2) 정치망 어장부근에는 6월의 와류형성과 8월의 수온약층 형성으로 어류가 군집을 하는데 영향을 미쳐 좋은 어획량을 보여 주고 있다. 3) 정치망 어장에서 어획수온범위는 11$^{\circ}C$~28$^{\circ}C$이며 좋은 어획량을 나타내는 범위는 21$^{\circ}C$~27$^{\circ}C$였다. 또한 염분의 범위는 31.60$\textperthousand$~34.80$\textperthousand$이고 어획이 가장 좋은 범위는 33.80$\textperthousand$~33.99$\textperthousand$였다. 4) 어획대상물의 어획순위는 삼치, 전갱이, 삼치, 정어리, 고등어, 갈치의 순으로 나타났다.

• Environmental Analysis Health and Toxicology
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• 제24권1호
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• pp.9-16
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• 2009

Effects of salinity and standard toxic metals on fertilization and embryo development rates were investigated in the sea urchin, Hemicentrotus pulcherrimus. Spawning was induced by injecting $1{\sim}2$ mL of 0.5 M KCl into the coelomic cavity. Males released white or cream-colored sperms and females released yellow or orange-colored eggs. The fertilization rate was below 30% when salinity was 20 psu and lower, but was almost above 90% when salinity was 25 psu and higher. The embryo development rate was below 60% when salinity was 25 psu and lower, but was above 80% when salinity was between 30 and 35 psu. The fertilization and embryo development rates in the control condition(not including Cu and Cd) were greater than 90%, but decreased a high negative correlation with the increasing of Cu(r=-0.80, r=-0.78) and Cd(r=-0.90, r=-0.82) concentrations, respectively. The fertilization and embryo development rates were significantly inhibited in the addition of Cu($EC_{50}$=17.30 ppb, $EC_{50}$=10.32 ppb) and Cd($EC_{50}$=364.57 ppb, $EC_{50}$=244.04 ppb), respectively. These results suggest that salinity concentrations for successful fertilization and normal embryogenesis of H. pulcherrimus are above 25 psu and 30 psu, respectively, and the biological assays of fertilization and embryo development rates using H. pulcherrimus are useful methods for the ecological toxicity test of marine pollution elements.