• 한국패류학회지
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• 제21권1호
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• pp.47-56
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• 2005

A series of radiotracer experiments were employed to quantitatively compare the biokinetics of uptake from the dissolved phase (influx rates), uptake from the various types of food source (assimilation efficiency), and loss (efflux) of Ag between Potamocorbula amurensis and Macoma balthica. Simultaneously, influx rates of dissolved Cd in both clams were determined to compare with those of Ag. Effects of salinity on influx rates were evaluated in these 2 euryhaline species, as were effects of clam size. Influx rate of Ag and Cd (${\mu}g g^{-1}$ [dry wt.] $d^{-1}$) increased linearly with metal concentrations. Influx rates of Ag in both clams were 3 to 4 times those of Cd. Absolute influx rates of the 2 metals were 4 to 5 times greater in P. amurensis than M. balthica, probably because of differences in biological attributes (i.e. clearance rate or gill surface area). As salinity was reduced from 20 to 2.5 psu, the influx rate of Cd in P. amurensis increased 4-fold and that of Ag increased 6-fold, consistent with expected changes in speciation. Weight-specific metal influx rates (${\mu}g g^{-1}$ [dry wt.] $d^{-1}$) were negatively correlated with the tissue dry weight of the clams, but most rate constants determining physiological turnover of assimilated metals were not affected by clam size.

• Journal of Microbiology and Biotechnology
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• 제20권9호
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• pp.1288-1294
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• 2010

Rhizobium phaseoli strains were isolated from the mung bean (Vigna radiata L.) nodules, and the most salt tolerant and high auxin producing rhizobial isolate N20 was evaluated in the presence and absence of L-tryptophan (L-TRP) for improving the growth and yield of mung bean under saline conditions in a pot experiment. Mung bean seeds were inoculated with peat-based inoculum and NP fertilizers were applied at 30-60 kg/ha, respectively. Results revealed that imposition of salinity reduced the growth and yield of mung bean. On the contrary, the separate application of L-TRP and Rhizobium appeared to mitigate the adverse effects of salt stress. However, their combined application produced more pronounced effects and increased the plant height (28.2%), number of nodules per plant (71.4%), plant biomass (61.2%), grain yield (65.3%), and grain nitrogen concentration (22.4%) compared with untreated control. The growth promotion effect might be due to higher auxin production in the rhizosphere and improved mineral uptake that reduced the adverse effects of salinity. The results imply that supplementing Rhizobium inoculation with L-TRP could be a useful approach for improving the growth and yield of mung bean under salt stress conditions.

• 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.

• 한국어류학회지
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• 제18권3호
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• pp.202-208
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• 2006

점농어 치어의 수온과 염분에 따른 대사율 변화를 조사하기 위해 평균 무게 $5.5{\pm}0.3g$인 개체를 대상으로 수온 (15, 20, $25^{\circ}C$)과 염분 (0, 15, 30 psu)에 따른 산소 소비율을 측정하였다. 9가지 실험 조합의 산소 소비율은 유수식 형태의 호흡실을 이용하여 24시간 동안, 3반복 측정하였다. 수온은 점농어 치어의 산소 소비율에 유의한 영향을 미쳤지만(p<0.001), 염분과 수온 염분의 상호작용은 영향을 미치지 않았다(p>0.05). 각 염분 조건에서 수온 상승에 따라 산소 소비율은 유의적으로 증가하였다(p<0.001). 15, 20 그리고 $25^{\circ}C$에서의 시간당 평균 산소 소비율은 각각 328.8~342.3, 433.9~441.0 그리고 $651.5{\sim}659.9mg\;O_2\;kg^{-1}\;h^{-1}$이었다. $Q_{10}$ 값은 염분의 영향은 받지 않았으며, 수온에 따라 변하였다. 15~20, $20{\sim}25^{\circ}C$ 그리고 전 수온 범위에서의 $Q_{10}$ 값은 각각 1.63~1.75, 2.24~2.26 그리고 1.92~1.98이었다. 대사에 의한 에너지 손실은 수온의 증가에 따라 유의하게 증가하였다(p<0.001). 15, 20 그리고 $25^{\circ}C$에서의 호흡 대사로 인한 일간 평균 에너지 손실은 각각 224.6~233.8, 296.3~301.2 그리고 $444.9{\sim}450.7kJ\;kg^{-1}\;d^{-1}$이었다. 이 실험 결과는 점농어 치어를 염분 적응 후 염분 차이에 의한 에너지 손실 없이 해수뿐만 아니라 담수에서 사육이 가능하다는 것을 나타내며, 사육관리 및 성장을 위한 생체역학 모델 결정에 활용할 수 있다.

• 한국해양환경ㆍ에너지학회지
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• 제14권2호
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• pp.130-137
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• 2011

부영양화가 진행된 연안역의 퇴적환경개선을 목적으로, 수정만으로 부터 분리한 저서미세조류 Achnanthes sp., Amphora sp., Navicula sp.와 Nitzschia sp.의 성장에 미치는 수온과 염분의 영향을 정치배양으로 살펴보았다. 최대 성장속도는 Achnanthes sp.의 경우 $25^{\circ}C$와 25 psu(0.60 /day), Amphora sp.에서 $15^{\circ}C$와 25 psu(0.56 /day), Navicula sp.에서 $20^{\circ}C$와 30 psu(0.53 /day) 그리고 Nitzschia sp.에서 $20^{\circ}C$와 25 psu(0.48 /day)로 나타났다. 그리고 4종의 최적성장(최대성장 속도의 70% 이내)로부터, Amphora sp., Navicula sp.와 Nitzschia sp.는 광온성 및 광염성종으로 나타났으며, Achnanthes sp.는 낮은 수온영역에서 성장하기 어려운 협온성 종으로 특징지을 수 있었다. 따라서 Amphora sp., Navicula sp.와 Nitzschia sp.는 부영양화나 빈산소수괴 문제와 같이 오염된 연안역의 개선을 위한 식물환경복원용으로 유용한 미세조류일 것으로 판단된다.

• The Plant Pathology Journal
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• 제24권4호
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• pp.407-416
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• 2008

Studies were conducted to determine the effects of temperature, solute potential and carbon source on the mycelial growth, sclerotia development, and apothecium production of an isolate of Sclerotinia sclerotiorum. Mycelial growth rate was greatest at $25^{\circ}C$ on potato dextrose agar (PDA) medium amended with up to 2% NaCl (${\psi}s{\leq}1.91\;MPa$) and thereafter, growth rate declined. The least number of sclerotia were produced at $20^{\circ}C$on both PDA and malt extract agar (MEA) amended with 8% NaCl (${\psi}s=6.62\;MPa$). With increasing temperature and decreasing solute potential the number and size of sclerotia were significantly reduced. The combined effect of temperature, solute potential and carbon source on sclerotia production were highly significant and had an impact on the development of the rind layer cells of sclerotia. These cells lacked a transparent cell wall which was surrounded by a compact melanized layer, and some of these cells appeared to be devoid of cell contents or were totally vacuolated. The survival of the sclerotia with increase in salinity and temperature appeared to affect melanization and the nature of the rind cells. The observations of this study re-enforces the need for an integrated disease management to control S. sclerotiorum.

• 물과 미래
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• 제25권1호
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• pp.111-119
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• 1992

간척사업에 있어 용수원이 되는 깊은 담수화호에서는 체절후 온도 및 염분농도차에 의한 이층류가 발생하게 되며 이중 저층염분수는 밀도류 흐름의 구조특성상 배수\ulcorner문만으로 배제가 어려우므로 별도의 저층배수시설을 계획하여 담수호화를 촉진하고 있다. 성층화된 담수화호에서 상층부의 염도변화에 영향을 주는 요소로는 크게 나누어 세가지로 대별한다. 첫째는 상, 하층간의 밀도차에 의한 내부경계면의 난류현상, 둘째는 상층부의 흐름과 요동(바람,파)에 의한 혼합작용, 셋째는 하층부 호저토에서 발생되는 염분의 확산이다. 따라서 담수호화 모형을 위한 이층류흐름의 염분평행방정식을 구획하고 이 모형이 가지는 여러 가지 매개변수를 현장에서 실측된 염분농도변화에 부합하도록 유도하였다.

• 한국수산과학회지
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• 제46권3호
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• pp.252-258
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• 2013

The quality and quantity of food organisms in fish seed production are important. The marine microalgae Nannochloropsis oculata are used as initial food organisms in the field. We investigated the effects of salinity (0, 10, 20, 30, 40 and 50 psu) on the lipid and fatty acid composition of N. oculata. Cultivation of N. oculata at varying salinities showed the highest growth rate at 20 psu. Total lipid content ranged from 17.26 to 18.63% at salinities from 0 to 50 psu). The nonpolar lipid content increased markedly at 30 psu and was highest at 15.55%. The polar lipid content was lowest at 30 psu, by 84.45%. It was also found that the omega-3 and EPA contents were inversely proportional to salt concentration. For the polar and nonpolar lipid compositions, there was no significant effect of salinity. Omega-3 polyunsaturated fatty acid content especially the content of EPA in the seawater larvae is the essential fatty acid in this food organism. It is thus advantageous to culture N. oculata at 20 psu.

• 수산경영론집
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• 제46권3호
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• pp.63-72
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• 2015

This study aims to empirically analyze the relationship between climate change elements and catch amount of coastal fisheries, which is predicted to be vulnerable to climate change since its business scale is too small and fishing ground is limited. Using panel data from 1974 to 2013 by region, we tested the relationship between the sea temperature, salinity and the coastal fisheries production. A spatial panel model was applied in order to reflect the spatial dependence of the ocean. The results indicated that while the upper(0-20m) sea temperature and salinity have no significant influence on the coastal fisheries production, the lower(30-50m) sea temperature has significant positive effects on it and, by extension, on the neighboring areas's production. Therefore, with sea temperature forecast data derived from climate change scenarios, it is expected that these results can be used to assess the future vulnerability to the climate change.

• 한국양식학회지
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• 제17권4호
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• pp.246-250
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• 2004

Survival of 12.7 g (average body weight) Litopenaeus vannamei was examined at temperatures of 14, 16, 18, 28, 32, 34 and 36$^{\circ}C$ and salinities of l0, 20, 30 and 40 ppt after 7 days. Hemolymph osmolality was measured at 12 combinations of salinities (l0, 20, 30 and 40 ppt) and temperature levels (18, 28 and 34$^{\circ}C$) after 14 days. The results show that the species have their best survival between temperatures of 18 and 3$0^{\circ}C$ and salinity above 20 ppt. Hemolymph osmolality increased with increased salinity at all temperatures tested. The isosmotic point calculated from the linear relationship between hemolymph osmolality and medium osmolality and recorded as 826, 809 and 1,117 mOsm/kg which is equivalent to 29.4, 28.8 and 40.2 ppt at 18, 28 and 34$^{\circ}C$, respectively. The slopes obtained from the relationship between hemolymph osmolality and medium osmolality were 0.314, 0.276 and 0.541 for L. vannamei at 18, 28 and 34$^{\circ}C$, respectively, suggesting that the shrimp at 34$^{\circ}C$ regulated osmotic concentration much worse than those at 18 and 28$^{\circ}C$. This result also indicated that L. vannamei living at 34$^{\circ}C$, showed more fluctuation in hemolymph osmolality than those at 18 and 28$^{\circ}C$.