• ALGAE
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• v.21 no.3
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• pp.317-321
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• 2006

The effects pH and salinity on the brown alga Sargassum fulvellum were investigated in the context of the removal of two major associated animals, Caprella scaura and Gammaropsis utinomi. Optimum quantum yield (Fv/Fm) of S. fulvellum was also examined in the same experimental conditions as an index of stress. Experiments on pH and salinity tolerances of the two animal species indicated that mortality was more than 80% at extremes of pH (2, 3, 4, 10, 11, 12) and salinity (0, 3.5, 7, 10, 44 psu) after a 5 min treatment. Lethal time (LT50) from pH 2 to pH 4 was less than 90 sec in C. scaura, and less than 70 sec in G. utinomi. From 0 to 10 psu, LT50 was less than 20 sec in C. scaura and less than 60 sec in G. utinomi. The quantum yield of S. fulvellum was not significantly different from controls within the pH range 4~10, and within the salinity range of 7-40 psu. When exposed to pH and salinity conditions outside these ranges, the effect of these factors on the removal of two animal species was higher, but quantum yield was highly reduced. These results indicate that the optimal conditions for removing the animal species without affecting optimum quantum yield were pH 4-10, and salinities 7-10 psu and 44 psu.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.3
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• pp.194-198
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• 2004

This study was conducted to identify the appropriate nitrogen fertilizer application rate for improving rice quality in tidal reclaimed area, at the Gyehwado substation of the Honam Agricultural Research Institute during 2002-2(103. The experimental fields contained 0.1% (low salinity) and 0.3-0.4% (medium salinity) Nacl in soil solution. Plant height at panicle formation stage was tall ay heavy nitrogen level and the effect of heavy nitrogen was higher in low than in high soil salinity condition. Heading date was not affected by applied nitrogen levels from 8 to 16 kg/10a in low soil salinity condition but it was one day later in 24 kg/10a nitrogen level when compared with the standard nitrogen level,20 kg/10a. In middle soil salinity condition, the heading date was one day earlier in 8 to 16 kg/10a and similar in 24 kg/10a, when compared with 20 kg/10a nitrogen level. And also it was four days later in middle than in low soil salinity condition. In low soil salinity condition, grain number $\textrm{m}^2$ increased but ripened grain ratio decreased as the nitrogen application increased and finally, milled rice yield was not different among heavy nitrogen application levels compared with 12 kg/10a. Head rice ratio was high and protein content was low in 12 kg/10a or lower nitrogen level. In middle soil salinity condition, grain number $\textrm{m}^2$ increased and ripened grain ratio was not affected as the nitrogen application increased. And finally, milled rice yield increased with increasing nitrogen application levels, Head rice ratio was high and protein content was not affected by nitrogen application levels. Therefore, on the basis of milled rice yield and rice grain quality inreclaimed land, the appropriate nitrogen application level would be 12 kg/10a in low soil salinity condition and 20 kg/10a in middle soil salinity condition.

• Journal of Environmental Health Sciences
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• v.24 no.1
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• pp.120-131
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• 1998

This study was performed to define the physicochemical characteristics of food waste and food wastewater, and to find the effect of moisture content variation and salinity variation on aerobic composting for food wastes. In moisture content variation experiment, the samples of 2-1, 2-2, 2-3 and 24 were prepared by the moisture content of 83.8%, 70.9%, 64.8% and 45.1%, respectively. In salinity variation experiment, the samples of 3-1, 3-2, 3-3 and 3-4 were prepared by the salinity of 0.99%, 1. 69%, 1.75% and 2.34%, respectively. In both experiments, aerobic composting reactors were operated by the mode which was composed of half an hour's stirring and 2 hour's aeration per day, for 45 days. The followings are the conclusions that were derived from this study. 1. In the study of physicochemical characteristics of food waste and food wastewater, the values of pH were 4.19 and 3.96, the values of salinity were 0.91% and 1.17%, and the values of conductivity were 7.6 mS/cm and 18.2 mS/cm, respectively. 2. In food waste, the moisture content was 60.3%, organic compound content was 96.1%, total carbon was 48.0%, total nitrogen was 1.5%(therefore, C/N ratio was 32), and the concentration of total phosphorus was 1.34 mg/kg. 3. The time of temperature ascending was delayed, the highest temperature was lowered, the duration period of high temperature was shortened by the increasing of moisture content. In the higher moisture content, anaerobic condition was formed, bad smell was released, insects were gathered and multiplicated, and the reaction rate of composting was reduced. 4. In moisture content experiment, C/N ratios were changed from the range of 31.2-34.8 at the beginning phase to that of 20.4-28.4 at the last phase. 5. In salinity experiment, the reduction rate of volume was increased(40.3%) when the salinity was decreased(0.99%). Also, the reduction rate of mass was increased(51.8%) when the salinity was decreased(0.99%). This fact denotes that salinity hinders the process of composting. 6. the concentrations of total nitrogen and total phosphorus were increased from 0.74% to 1.10%, and from 0.82 mg/kg to 3.44 mg/kg, respectively when the salinity was decreased from 2.34% to 0.99%.

• KSBB Journal
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• v.16 no.4
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• pp.344-350
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• 2001

The effect of salinity stress of Brassica olearacea and Capsicum annuum were studied at various levels of salinity conditions(Na-gluconate, K-gluconate, NaCl, KCl). The effects of salinity stress were measured by seedling growth rates and secondary metabolites contents of the stressed plants. Each seedling studied on the response of different salinity stress. Seedling growth of Capsicum annuum was inhibited up to 200 mM salt tolerance and Brassica olearacea was inhibited up to 400 mM salt tolerance. The produced anthocyanin was separated to high value from 200 mM NaCl in case of Brassica olearana and 50 mM K-gluconate in case of Capsicum annuum. The BADH activity was very high in Brassica olearacea seedlings treated with 200 mM NaCl and in Capsicum annuum seedlings treated with 100 mM K-gluconate. The BADH activities were increased during the early culture days, it induced betaine synthesis. The salinity stress promoted BADH activiy, subsequently endogenous betaine contents were increased, and it seemed to be secure seedling from salinity stress. The salinity concentration of 200 mM was effective on the inhibition of seed germination and on the increase of proline accumulation in tissue. The inhibition of seedling growth and accumulation of secondary metabolites in seedling were caused osmotic hypersensitivity against salinity stress.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.2
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• pp.124-129
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• 2000

The purpose of this study is to estimate the degradation rate and process efficiency of the composting according to the salinity concentration. The samples of food waste for this study were collected in Pocheon-Gun, Kyungki-Do. The collected samples were adjusted to the optimum range of moisture content, pH and C/N ratio. After that, adding the saline, the samples with 3 different salinity concentrations(1%, 5% and 10%) were made. Then each sample was fed into the reactor with temperature controller. During the aerobic composting process, the change of the physical and chemical properties of the sample as temperature, pH, C/N ratio and $CO_2$ and $O_2$ concentration in the reactor were measured. From the experiment of this study, the result are following. The highest temperatures are $59^{\circ}C$ at RUN 1(1% salinity conc.), $49^{\circ}C$ at RUN 2(5% salinity conc.) and $45^{\circ}C$ at RUN 3(10% salinity conc.). The change of $CO_2$ production and $O_2$ consumption have the positive correlation with the change of the temperature. $CO_2$ production and $O_2$ consumption are peaked at the low salinity concentration. During composting, Run 1, RUN 2 and RUN 3 are increased pH to 8.9, 8.6 and 7.2 and slowly decreased C/N ratio to 18.9, 19.1 and 22.1 and moisture content to 51.1%, 53.7% and 55.0%, respectively. It is supposed that increasing salinity concentration causes the retarding of the microbial degradation activities during the composting. And for the efficient composting, the salinity concentration in the sample hat to be maintained below 5%.

• Horticultural Science & Technology
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• v.30 no.4
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• pp.417-425
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• 2012

Salinity stress is one of the most serious factors limiting the productivity of agricultural crops. The aim of this study was to assess inter-cultivar (intraspecific) variation for salinity tolerance in six Korean rapeseed (Brassica napus L.) cultivars at the seedling stage. The effect of three different salinity stress levels (EC 4, 8, and 16 $dS{\cdot}m^{-1}$) on seedlings of six cultivars was investigated through leaf size, leaf dry weight, and leaf chlorosis. At the highest salinity level (16 $dS{\cdot}m^{-1}$), the mean decrease of leaf dry weight in 'Sunmang', 'Tammi', 'Tamla', 'Naehan', 'Youngsan', and 'Halla' was about 56.2, 56.9, 78.4, 79.3, 77.4, and 80.9%, respectively. 'Tammi' and 'Sunmang' showed much less reduction in leaf dry weight than all the other cultivars. In addition, diluted seawater treatments increased the occurrence of leaf chlorosis in six cultivars. At EC 8 and 16 $dS{\cdot}m^{-1}$, 'Naehan', 'Youngsan', and 'Halla' showed a higher level of leaf chlorosis than 'Tammi' 'Sunmang', and 'Tamla'. On the basis of these results, six cultivars were placed into salinity-tolerant and sensitive groups. 'Tammi' and 'Sunmang' were the salinity-tolerant cultivars, while 'Naehan', 'Halla', 'Youngsan', and 'Tamla' were the salinity-sensitive cultivars. 'Tammi' and 'Naehan' rated as the most tolerant and most sensitive cultivar, respectively. To further analyze protein expression profiles in 'Tammi' and 'Naehan', 2-D proteomic analysis was performed using the plants grown under diluted seawater treatments. We identified eight differentially displayed proteins that participate in photosynthesis, carbon assimilation, starch and sucrose metabolism, amino acid metabolism, cold and oxidative stress, and calcium signaling. The differential protein expressions in 'Tammi' and 'Naehan' are likely to correlate with the differential growth responses of both cultivars to salinity stress. These data suggest that 'Tammi' is better adapted to salinity stressed environments than 'Naehan'.

• Horticultural Science & Technology
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• v.34 no.6
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• pp.818-829
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• 2016

This study evaluated the responses of 18 potato cultivars to three levels of salinity stress (electrical conductivity, EC: 1.0, 4.0, and $8.0dS{\cdot}m^{-1}$). Stem, leaf, root, chlorophyll, tuber yield, and proline content were investigated and statistically analyzed using analysis of variance (ANOVA) and correlations. Stem number and stem diameter were not affected by salinity, but stem length and aerial weight showed highly significant responses to salinity. Aerial weight decreased with increasing salinity levels in most cultivars, while it increased in some the cultivars 'Daejima', 'Goun', 'Haryeong', and 'LT-8'. Leaf number, leaf area index, and leaf weight were most significantly affected by salinity and the cultivar ${\times}$ salinity interaction. Root length, root weight, total chlorophyll and chlorophyll a were affected by salinity, but not by the cultivar ${\times}$ salinity interaction. The opposite trend was shown in chlorophyll b. Although there was great variability among cultivars, tuber yield decreased in all cultivars, and was most significantly influenced by salinity and the cultivar ${\times}$ salinity interaction. 'Superior', 'Kroda', 'Romana', and 'Duback' gave better tuber yields under salinity at EC 4.0 and $8.0dS{\cdot}m^{-1}$ than the cultivars with better aerial weights. Proline content was increased by salinity in all cultivars, and was more remarkable in the cultivars with better aerial weights than in cultivars such as 'Superior' and 'Kroda' with better tuber yields. Leaf number, leaf area index, leaf weight, and root length parameters were considered to be useful criteria in the evaluation of salt tolerance because of their high positive correlation with tuber yield; however, given its negative correlation with tuber yield under high salinity, proline content was not. Salinity tolerances varied greatly among potato cultivars. The low correlation between growth and yields of aerial parts under high salinity suggests that, in commercial agriculture, it might be more practical to compare relative yields to controls. Additionally, 'Superior', 'Kroda', 'Romana', and 'Duback' might be very useful cultivars to use in breeding programs to develop salinity-tolerant potatoes, as well as for sustainable potato production in saline areas.

• Mycobiology
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• v.33 no.1
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• pp.51-60
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• 2005

Pot greenhouse experiments were carried out to attempt to increase the salinity tolerance of one of the most popular legume of the world; cowpea; by using dual inoculation of an Am fungus Glomus clarum and a nitrogen-fixer Azospirillum brasilense. The effect of these beneficial microbes, as single- or dual inoculation-treatments, was assessed in sterilized loamy sand soil at five NaCl levels ($0.0{\sim}7.\;2ds/m$) in irrigating water. The results of this study revealed that percentage of mycorrhizal infection, plant height, dry weight, nodule number, protein content, nitrogenase and phosphatase activities, as well as nutrient elements N, P, K, Ca, Mg were significantly decreased by increasing salinity level in non-mycorrhized plants in absence of NFB. Plants inoculated with NFB showed higher nodule numbers, protein content, nitrogen concentration and nitrogenase activities than those of non-inoculated at all salinity levels. Mycorrhized plants exhibited better improvement in all measurements than that of non-mycorrhized ones at all salinity levels, especially, in the presence of NFB. The concentration of $Na^+$ was significantly accumulated in cowpea plants by rising salinity except in shoots of mycorrhizal plants which had $K^+/Na^+$ ratios higher than other treatments. This study indicated that dual inoculation with Am fungi and N-fixer Azospirillum can support both needs for N and P, excess of NaCl and will be useful in terms of soil recovery in saline area.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.9 no.4
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• pp.199-206
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• 2011

The influence of water salinity on the hydraulic conductivities of compacted bentonites with several dry densities were studied. The hydraulic conductivity increases with increasing salinity only when the dry density of bentonite is relatively low. The degree of increase becomes more remarkable at a lower dry density of bentonite. For bentonite with the density of 1.0 $Mg/m^3$ and 1.2 $Mg/m^3$, the hydraulic conductivity of the 0.4 M NaCl solution increases up to about 7 times and 3 times, respectively higher than that of freshwater. However, for the bentonite with a dry density higher than 1.4 $Mg/m^3$, the salinity has an insignificant effect on the hydraulic conductivity, and the hydraulic conductivity is nearly constant within the salinity range of 0.04 to 0.4 M NaCl. The pre-saturation of the bentonite specimen with freshwater has no significant influence on the hydraulic conductivity.

• Korean Journal of Materials Research
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• v.26 no.7
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• pp.382-387
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• 2016

Gas hydrates are crystalline solids in which gas molecules (guests) are trapped in water cavities (hosts) that are composed of hydrogen-bonded water molecules. During the formation of gas hydrates in seawater, the equilibria and kinetics are then affected by salinity. In this study, the effects of salinity on the equilibria of $CO_2$ and R134-a gas hydrates has been investigated by tracing the changes of operating temperature and pressure. Increasing the salinity by 1.75% led to a drop in the equilibrium temperature of about $2^{\circ}C$ for $CO_2$ gas hydrate and $0.38^{\circ}C$ for R-134a gas hydrate at constant equilibrium pressure; in other words, there were rises in the equilibrium pressure of about 1 bar and 0.25 bar at constant equilibrium temperature, respectively. The kinetics of gas hydrate formation have also been investigated by time-resolved in-situ Raman spectroscopy; the results demonstrate that the increase of salinity delayed the formation of both $CO_2$ and R134-a gas hydrates. Therefore, various ions in seawater can play roles of inhibitors for gas hydrate formation in terms of both equilibrium and kinetics.