• 한국수산과학회지
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• 제16권4호
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• pp.335-340
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• 1983

양식 김에 미치는 수온, 염분 및 해수중의 현탁부니의 영향을 조사하였다. 1. 김의 광합성률은 실험수온 $8{\sim}16^{\circ}C$까지는 수온이 높아짐에 따라 증가하였으나 $18^{\circ}C$에서는 감소되었다. 2. 실험염분 $21.5{\sim}33.5\%0$ 범위에서, 김의 광합성률은 $29.5\%0$에서 다소 증가하였고 $21.5\%0$에서는 감소하였다. 3. 김의 광합성률은 부니의 농도가 증가함에 따라 또 처리일수가 경과함에 따라 현저히 감소하였다. 4. 김의 광합성률에 미치는 염분과 부니의 복합영향을 보면, 저염분영향이 큰 $21.5\%0$에서 부니의 영향이 컸고, $33.5\%0$에서도 비슷한 경향을 보였다. 5. 김의 생체량은 부니의 농도가 증가함에 따라 또 처리일수가 경과함에 따라 현저히 감소하였다.

• 수산해양교육연구
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• 제26권6호
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• pp.1315-1321
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• 2014

We investigated the optimum salinity and temperature conditions for the mass culture of small rotifer, Proales similis. In the salinity experiment ranging from 1, 5, 10, 15, 20, 25 and 33‰, growth tended to decrease with salinity increase. Most agreeable salinity for rotifer growth was 1‰ in which maximum density and specific growth rate (SGR) were obtained. In the temperature experiments ranging from 15, 20, 25, 30 and $35^{\circ}C$, continuous growth of rotifer populations was found up to $35^{\circ}C$. The highest maximum density (2,060 inds./mL) of rotifer was observed at $25^{\circ}C$ in given temperature regime. Also, the SGR of females showed increasing tendencies with the increase of temperature. These results suggest that the optimum salinity and temperature for mass culture of P. similis may be 1‰ and $25^{\circ}C$, respectively.

• 한국수산과학회지
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• 제54권4호
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• pp.426-433
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• 2021

This study aimed to determine the appropriate salinity condition for optimal cultivation of the juvenile hybrid grouper Epinephleus akaara♀×E. lanceolatus♂ in conditions of decreasing salinity. The survival, growth, metabolic rate, stress, and histological response were investigated in juvenile hybrid grouper exposed to different salinities for 30 days. At 0 psu, the survival rate of the juvenile hybrid grouper was 60% on the 2nd day of exposure and all individuals died on the 3rd day of exposure. At salinities above 3 psu, all animals survived throughout the exposure period. Growth rate for body weight of the juvenile hybrid grouper was the highest in the control and the lowest at 10 psu. Plasma osmolality of the juvenile hybrid grouper exposed to different salinities was 313-355 mg Osmol/kg at salinities above 10 psu, and then decreased to 225-264 mg Osmol/kg at salinities below 5 psu. The oxygen consumption rate tended to decrease as the salinity decreased. Stress responses of the juvenile hybrid grouper were analyzed with decreasing salinity. Therefore, it is considered that a salinity of more than 20 psu is suitable for the culture of the juvenile hybrid grouper.

• Journal of Ecology and Environment
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• 제35권2호
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• pp.73-78
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• 2012

$Calotropis$ $procera$ L. is a perennial shrub distributed in saline areas of deserts of South Asia. Salt stress is a very challenging subject in arid and semi-arid areas. Germination stage is very sensitive and many plants do not germinate in saline soil. The objective of this study was identifying the salinity effect on seed germination of $Calotropis$ $procera$ L. The experimental design was a complete randomized block design with NaCl and $CaCl_2$ at five levels of isobar concentrations: 0.0, -0.01, -0.05, -0.1, and -0.15 MPa. Osmotic potential had significant effects ($P$ < 0.01) on germination percentage, germination rate, shoot length, root length, and seedling dry weight. All seedling characteristics decreased with decrease in osmotic potential. Shoot length and root length decreased more than the seedling characteristics. Germination was completely inhibited in -0.1 Mpa. Priming with NaCl and $CaCl_2$ (-0.1 MPa) for four days had significant effects ($P$ < 0.01) on the germination percentages. Priming improved the seedling characteristics in all samples, especially in -0.05 Mpa, but a decrease with decrease in osmotic potential.

• 한국양식학회지
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• 제22권1호
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• pp.28-33
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• 2009

본 연구에서는 강도다리의 담수순화방법으로 급격한 염분변화(AD)와 단계적인 염분변화(SD II과 III)를 주었을 때 강도다리의 생리적 반응을 조사하였다. AD에서 Ht, RBC 및 Hb는 Exp. II에 비해 증가하는 값이 높게 나왔으며 회복하는 속도도 느렸다. 그러나 SD II는 Ht, RBC 및 Hb에서 실험개시시수준과 실험종료시의 값이 유의한 차이를 보이지 않았다. AD에서 cortisol의 농도는 실험개시시 $2.1{\pm}1.0{\mu}g/mL$로부터 실험개시 후 6시간째에 $13.7{\pm}0.2{\mu}g/mL$ 급격히 증가하였으나 10일째에 $3.10{\mu}g/mL$로 실험개시시 수준으로 회복되었다. SD I에서 cortisol의 농도는 실험개시시 $2.1{\pm}1.0{\mu}g/mL$로부터 6시간째에 $13.6{\pm}0.6{\mu}g/mL$로 증가하였고, 실험종료시인 10일째에 $3.1{\pm}0.4{\mu}g/mL$로 회복되었다. SD II에서 cortisol의 농도는 실험개시시 $2.1{\pm}1.0{\mu}g/mL$로부터 6시간째와 12시간째에 각각 $10.5{\pm}2.5$, $10.8{\pm}5.6{\mu}g/mL$로 증가하는 경향을 보였으나 48시간째부터 실험개시시 수준으로 회복되는 경향을 보였다. 글루코스 농도는 AD, SD I과 II에서 cortisol의 경향과 다르게 유의한 차이를 나타내지 않았다. 삼투질농도는 실험개시시 $286.8{\pm}3.3\;mOsm/kg$으로 나타났으며, AD와 단계적 염분변화 실험구인 SD I, II에서는 실험종료 시에 각각 $266.3{\pm}8.5$, $242.0{\pm}12.5$, $269.5{\pm}4.9\;mOsm/kg$으로 유의하게 감소하는 경향을 보였다. 혈장의 $Na^+$, $K^+$ 및 $Cl^-$ 농도는 AD의 경우, $Cl^-$(mEq/L)만이 실험개시시의 수준과 유의한 변화를 볼 수 없었고, $Na^+$(mEq/L)와 $K^+$(mEq/L)는 유의하게 감소하는 경향을 보였다. SD I에서도 $Cl^-$(mEq/L)만이 실험개시시의 수준과 유의한 변화를 볼 수 없었고, $Na^+$(mEq/L)와 $K^+$(mEq/L)는 유의하게 감소하는 경향을 보였다.

• Membrane and Water Treatment
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• 제9권1호
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• pp.53-62
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• 2018

In this study, vacuum membrane distillation (VMD) was used to treat high-salinity wastewater (concentration about 17%) discharged by chlor-alkali plant after resin regeneration. The feasibility of VMD for the treatment of real saline wastewater by using Polyvinylidene fluoride (PVDF) microporous plate membrane with a pore diameter of $0.2{\mu}m$ was investigated. The effects of critical operating parameters such as feed temperature, velocity, vacuum degree and concentration on the permeate water flux were analyzed. Numerical simulation was used to predict the flux and the obtained results were in good agreement with the experimental data. The results showed that an increase in the operating conditions could greatly promote the permeate water flux which in turn decreased with an increase in the concentration. When the concentration varied from 17 to 25%, the permeate water flux dropped marginally with time indicating that the concentration was not sensitive to the decrease in permeate water flux. The permeate water flux decreased sharply until zero due to the membrane fouling resistance as the concentration varied from 25 to 26%. However, the conductivity of the produced water was well maintained and the average value was measured to be $4.98{\mu}s/cm$. Furthermore, a salt rejection of more than 99.99% was achieved. Overall, the outcome of this investigation clearly indicates that VMD has the potential for treating high-salinity wastewater.

• 한국농공학회논문집
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• 제62권3호
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• pp.85-94
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• 2020

Since the salinity of irrigation water is a critical constraint to the production of certain vegetable crops, salinity was considered as one of the most important factors of irrigation water. The purpose of this study were to monitor and assess the effects of saline irrigation water on strawberry and red radish growth in protected cultivation. One control and three treatments, which were differentiated according to the level of salinity in irrigated water, were employed for each vegetable to assess the effects of the irrigation with saline water. Monitoring has shown that using irrigation water with salinity above a certain level causes excessive accumulation of sodium (Na⁺) in both strawberry and red radish. Increased Na+ content was analyzed to be able to decrease the sugar content in strawberry. In addition, the salinity higher than the threshold level of irrigation water was found to reduce the growth and yield of strawberry and red radish. This study could contribute to suggest criteria for safe use of saline water in protected cultivation, although long-term monitoring is needed to get more representative results.

• 한국수산과학회지
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• 제46권2호
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• pp.201-215
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• 2013

The characteristics of the oceanographic environment in the Aleutian Basin of the Bering Sea during spring in 1996, 1997, and 1999 were clarified. An investigation of the water properties revealed five basic layers in the Bering Sea during spring: (1) a surface layer of warm and low-salinity water induced by solar heating, (2) a subsurface layer of cold and low-salinity water propagated slowly by heat from the surface layer, (3) a thermocline layer where salinity was constant but temperature sharply decreased, (4) a temperature inversion layer, and (5) a deep layer with a gradual decrease in temperature and increase in salinity toward the bottom. The ranges of water temperature and salinity were $1.8-5.5^{\circ}C$ and 31.81-34.08 in 1996, $1.5-7.2^{\circ}C$ and 31.9-34.06 in 1997, and $0.5-5.6^{\circ}C$ and 32.0-34.11 in 1999, respectively. The water temperature of the surface layer was approximately $1.6^{\circ}C$ higher in 1997 than in 1996 and 1999. The lowest temperature at a depth of 100-150 m was about $1^{\circ}C$ lower in 1999 than in 1996 and 1997. Nutrient levels (nitrate, phosphate, and silicate) contributing to the control of the growth of phytoplankton were higher in the Aleutian Basin than in the eastern continental shelf and Bogoslof Island area. This was closely associated with the phytoplankton distribution. Nutrient concentrations were lowest at a depth of 25 m. The high primary production at that depth was confirmed from the vertical distribution of chlorophyll a. Chlorophyll a levels were above $4.0{\mu}L^{-1}$ in some areas in 1996 and 1999, but below $2.0{\mu}L^{-1}$ in most areas in 1997. Zooplankton density was about three times higher in 1999 than in 1997.

• Journal of Plant Biotechnology
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• 제42권3호
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• pp.168-179
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• 2015

We previously identified the rice gene, OsSAP, as an encoder of a highly conserved putative senescence-associated protein that was shown to have anti-apoptotic activity. To confirm the role of OsSAP in inducing abiotic stress tolerance in rice, we introduced OsSAP and AtBI-1, a plant homologue of Bax inhibitor-1, under the control of the CaMV 35S promoter into the rice genome through Agrobacterium-mediated transformation. The OsSAP transformants showed a similar chlorophyll index after salinity treatments with AtBI-1. Furthermore, we compared the effects of salinity stress on leaves and roots by examining the hormone levels of abscisic acid (ABA), jasmonic acid (JA), gibberellic acid (GA3), and zeatin in transformants compared to the control. With the exception of phytohormones, stress-induced changes in hormone levels putatively related to stress tolerance have not been investigated previously. Hormonal level analysis confirmed the lower rate of stress in the transformants compared to the control. The levels of ABA and JA in OsSAP and AtBI-1 transformants were similar, where stress rates increased after one week and decreased after a two week period of drought; there was a slightly higher accumulation compared to the control. However, a similar trend was not observed for the level of zeatin, as the decrease in the level of zeatin accumulation differed in both OsSAP and AtBI-1 transformants for all genotypes during the early period of salinity stress. The GA3 level was detected under normal conditions, but not under salinity stress.

• 한국수산과학회지
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• 제53권4호
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• pp.620-627
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• 2020

Oxygen consumption and blood physiology of olive flounder Paralichthys olivaceus (mean body weight 106.6±6.8 g, mean±SD) was investigated at salinities of 34.0 (control), 33.7, 33.3, 32.6, 31.3, 28.6, 23.1, 12.2 and 0.0 psu at 20.0℃, respectively. Stepwise salinity changes (34.0→33.7→33.3→32.6→31.3→28.6→23.1→12.2→0.0 psu) with an interval of 24 h for each salinity induced a significant (P<0.05) increase of oxygen consumption rate (OCR) in fish exposed from 31.3 to 0.0 psu compared to that of control fish. The maximum OCR was found in fish exposed to 23.1 psu, which was accompanied by 36.2% higher energy consumption than the control fish. Fish exposed to each salinity for 24 h induced a significant decrease of blood plasma Na⁺ in 0.0 psu and Cl^- in 12.2 and 0.0 psu (P<0.05), and increase of plasma glutamic oxaloacetic transaminase (GOT) in 0.0 psu compared to the control fish (P<0.05). The results of this experiment show that P. olivaceus exposed to concentrations below 31.3 psu requires more energy costs to adapt to salinity changes than 34.0 psu under our experimental conditions.