• Korean Journal of Microbiology
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• v.37 no.2
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• pp.124-129
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• 2001

For elucidating the effect of salinity to the effect of wastewater treatment, the heterotrophic bacterial numbers, total bacterial numbers, and the bacterial community structure by FISH method were analyzed. The total bacterial numbers were not significantly changed by the salinity. But the heterotrophic bacterial numbers and bacterial community structures were drastically changed by the increase of salinity. In case of 1% salinity, the heterotrophic bacterial numbers and structure were slightly changed comparing to those of contol. In case of 2% and higher salinities, the numbers of heterotrophic bacteria and the proportions of Eubacteria, Proteobacteria $\alpha$-group, $\rho$-group and Cytophaga-Flavobacterium groups were deceasing. By these results, the salinity stress to bacterial community in waste water treatment was unveiled, and for sustaining the waste water treatment system, the salinity should be lower than 1%.

• Journal of Plant Biology
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• v.36 no.3
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• pp.219-224
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• 1993

The effects of environmental factors on the growth of Enteromorpha compressa germlings from Daeyulri (34$^{\circ}$36'N; 127$^{\circ}$47'E), the southern cost of Korea were examined in laboratory culture through combinations of irradiance and salinity and temperature and salinity. They showed a maximum growth rate at 125 $\mu$E.m-2.s-1 and 32$\textperthousand$ of irradiance and salinity combination, and at 15$^{\circ}C$ and 32% of temperature and salinity combination. Optimal parameters for the growth of germlings were 15$^{\circ}C$, 125 $\mu$E.m-2s-1 and 32$\textperthousand$. The germlings of E. compressa were survived in a wide range of irradiance, temperature and salinity levels, even though they had relatively low irradiance optimum. In the field E. compressa occurred commonly during autumn and spring seasons and disappeared in summer, except for particular habitats. This may be caused by the salinity and water temperature of this area rarely drop below 26$\textperthousand$ and 8$^{\circ}C$ during winter. A broad tolerance to environmental and rapid growth of germlings made them a wide geographical distribution over the world and a survival in both the upper and lower intertidal zones.

• 한국해양학회지
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• v.27 no.4
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• pp.290-302
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• 1992

Seasonal variations of salinity in the upper 500 m of the tropical Atlantic Ocean are examined, based on both climatological seasonal salinity observations and numerical simulations with hydrological forcing. The seasonal cycle of sea surface salinity has strong seasonal variations caused by shifts of the freshwater surplus zone (i.e. the intertropical convergence zone) and the river outflow. The climatological seasonal salinity in this analysis concurs with other independent observations described by Default (1981) and Levitus (1982), but provides more consistent patterns with temperature structure. The effect of salinity on density below 100 m depth in the tropical Atlantic is negligible compared to tat of temperature, which in the mixed layer salinity affects density significantly. The systematic difference between observed and simulated salinity is found to be the fact that the simulated salinity is higher in the subtropics than the observed salinity, and possible sources about the difference are also discussed.

• Korean Journal of Environmental Biology
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• v.33 no.4
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• pp.450-458
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• 2015

The heat shock proteins (Hsps), one of the most highly conserved groups of proteins, play crucial roles in protecting cells against environmental stressors, such as temperature, salinity, heavy metals and pathogenic bacteria. The glutathione S-transferases (GST) have important role in detoxification of oxidative damage, environmental chemicals and environmental stress. The purpose of this study is to investigate the gene expression of Hsp70 and GST on change of temperature and salinity in Mytilus coruscus. The M. coruscus was cultured in incubator of separate temperature and salinity (8, 20, $30^{\circ}C{\times}20$‰, 25‰, 30‰) for 28 days. Ten individuals in each group were selected after each 14 and 28 days exposure. Results that the expression of Hsp70 mRNA was no significant changed in M. coruscus exposed to temperature ($8^{\circ}C$, $20^{\circ}C$, $30^{\circ}C$) and salinity (20‰, 25‰, 30‰) for 14 days. Whereas the expression of Hsp70 mRNA was increased in exposure to temperature $30^{\circ}C$ and salinity (20‰, 25‰, 30‰) for 28 days. The expression of GST mRNA was increased in exposure to temperature $30^{\circ}C$, salinity (25‰, 30‰) for 14 days and temperature ($8^{\circ}C$, $20^{\circ}C$, $30^{\circ}C$), salinity (20‰, 25‰, 30‰) for 28 days. These results suggest that Hsp70 and GST were played roles in biomarker gene on the thermal and salinity stress.

• Journal of Environmental Science International
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• v.22 no.9
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• pp.1115-1129
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• 2013

The study area is located on the western coast, and the inner development construction has been ongoing since 2011. The purposes of current study are to effectively simulate and quantitatively predict a temporal and spatial distributions of water temperature and salinity due to the stages of inner development construction in saemangeum reclaimed area. The transient-state numerical modeling using EFDC model is done, and the numerical simulation results are validated reasonably by repetitive numerical model calibration procedures with respect to field measurements of water temperature and salinity. The spatial distributions of water temperature and salinity show similar trends before and after construction of the dikes. In spring season, the salinity has maximum value of 21 psu, while, in summer season, the salinity shows 7 psu in a whole modeling domain. Thus, it is clearly observed that salt water is replaced by freshwater. However, the salinity and temperature reach their initial conditions at the end of the year. The salinity after construction of the dikes is lower than that before construction of them at Mankyeong area. On the other hands, after construction of the dikes, the salinity after dredging operations is higher than that before dredging. Because drastical increasing of water volume in Saemangeum Lake leads to increasing of stagnation time at bottom layer, and salt water is easily intruded to the two estuaries. Therefore, it may be concluded that hydrodynamic characteristics on Saemangeum are dominated by either Mankyeong and Dongjin discharge or sluice gates in/out-flow amounts, and thus they must be properly considered when rigorous and reasonable predictions of water temperature and salinity according to the stages of inner development construction.

• Journal of Aquaculture
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• v.16 no.1
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• pp.31-36
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• 2003

Two experiments were conducted for the physiological and growth responses of yearling sea bass, Lateolabrax japonicus (total length 24.4$\pm$1.5 cm, body weight 125.4$\pm$25.4 g) by the manipulation of salinity. To study the physiological responses of the sea bass by acute salinity change, we changed water salinity from 30 ppt into 2 ppt in rearing tank through 1 hour or 6 hour. To access the effect of salinity in the growth of sea bass, we also examined the growth of the sea bass in 2, 10, 20 and 30 ppt for 180 days. After salinity change, all yearlings appeared some stress response and ions changes in blood. The yearlings showed a slow recovery by an acute salinity exchange, but a fast recovery by slow salinity exchange. In the study about the influence of salinity in growth, although the food intake of yearlings in 20 ppt was significantly higher than the yearling in the other salinities, feed efficiency was higher in 10 ppt than the other salinities. However, the food intake and the feed efficiency in 2 ppt were significantly lower than in other groups. The growth of yearlings was significantly faster in 20 ppt than in the other salinities, but the growth showed significantly slower in 2 ppt than in the other salinities.

• Journal of the Korean earth science society
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• v.41 no.5
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• pp.469-477
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• 2020

Salinity is not only an important variable that determines the density of the ocean but also one of the main parameters representing the global water cycle. Ocean salinity observations have been mainly conducted using ships, Argo floats, and buoys. Since the first satellite salinity was launched in 2009, it is also possible to observe sea surface salinity in the global ocean using satellite salinity data. However, the satellite salinity data contain various errors, it is necessary to validate its accuracy before applying it as research data. In this study, the salinity accuracy between the Soil Moisture Active Passive (SMAP) satellite salinity data and the in-situ salinity data provided by the Ieodo ocean research station was evaluated, and the error characteristics were analyzed from April 2015 to August 2020. As a result, a total of 314 match-up points were produced, and the root mean square error (RMSE) and mean bias of salinity were 1.79 and 0.91 psu, respectively. Overall, the satellite salinity was overestimated compare to the in-situ salinity. Satellite salinity is dependent on various marine environmental factors such as season, sea surface temperature (SST), and wind speed. In summer, the difference between the satellite salinity and the in-situ salinity was less than 0.18 psu. This means that the accuracy of satellite salinity increases at high SST rather than at low SST. This accuracy was affected by the sensitivity of the sensor. Likewise, the error was reduced at wind speeds greater than 5 m s^-1. This study suggests that satellite-derived salinity data should be used in coastal areas for limited use by checking if they are suitable for specific research purposes.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.3
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• pp.238-242
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• 2003

Reclaimed tidal areas for rice cultivation are irrigated with salt mixed water when there is severe drought. Therefore, we identified the critical concentration of saline water for rice growth on a reclaimed saline soil in Korea. The experiment was conducted at the Kyehwado substation of the National Honam Agricultural Experiment Station (NHAES) during 2001-2002. Two experimental fields with 0.1-0.2% for low soil salinity and 0.3-0.4% for medium soil salinity levels were used. The experiment involved four levels of salt solution mixed with sea water (at 0.1, 0.3, 0.5, 0.7%) compared with a control using tap water in a split-plot design with three replicates. Saline solution was applied only two times at seedling stage (10 DAT and 25 DAT) for 5 days. Gyehwabyeo and dongjinbyeo, japonica rice varieties, were used in this experiment. Plant height and number of tillers sharply decreased in the 0.5% saline water in low soil salinity level and 0.1% in medium soil salinity level. For yield components, panicle number per unit area and percentage of ripened grain dramatically decreased in the 0.5% saline water in low soil salinity and 0.1% in medium soil salinity level. But 1,000-grain weight of brown rice decreased sharply in the 0.5% saline water in low soil salinity and 0.3% in medium soil salinity, indicating that this component was not much affected unlike other yield components. Milled rice yield decreased significantly with saline water level in both low and medium soil salinity. In the 0.7% low saline soil, the yield index was only 36% compared with the control. In medium soil salinity, even the control plot showed only 62% yield index compared with the control in the low soil salinity treatment. Results indicated that the critical concentration of saline water for rice growth in terms of economical income of rice production was 0.5% in low soil salinity and tap water in medium soil salinity.

• Fisheries and Aquatic Sciences
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• v.5 no.3
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• pp.229-234
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• 2002

Possibility of raising sunshine bass during the winter season in Korea was investigated. Also, the effect of feed on growth and body composition of sunshine bass was compared at the various salinity. Twenty sunshine bass $(Mean\;weight\;\pm S.D.\: :\;53.9 \pm 0.24 g)$ were stocked into the eighteen circular flow-through tanks. A 2 (feed) $\times$ 3 (salinity) factorial design with triplicate was used for this study. Feed was prepared into the 2 groups: the raw fish-based me>ist pellet (MP) containing $59.5\%$ crude protein and $9.4\%$ crude lipid, and commercial sinking red sea bream feed (CF) containing $49.9\%$ crude protein and $9.4\%$ crude lipid, respectively. And salinity was prepared into the 3 groups: freshwater $(0\%)$, brackishwater $(15\%)$, and seawater $(32\%)$. Fish were fed to satiation twice daily for 6 days a week. Fish were all survived at the end of the 8-week feeding trial. Weight gain (WG) and specific growth rate (SGR) of sunshine bass were significantly (P<0.05) affected by both feed and salinity. WG and SGR of sunshine bass fed the MP were significantly (P<0.05) higher than those of fish fed the CF in the same salinity. Amount of dry feed fed was significantly (P<0.05) affected by both feed and salinity. Feed consumption by sunshine bass fed on the MP was significantly (P<0,05) higher than by fish fed on the CF in the same salinity. Feed efficiency ratio (FER) was significantly (P<0,05) affected by salinity, but not by feed. Protein efficiency ratio (PER) was significantly (P<0.05) affected by both feed and salinity. Moisture and protein content of the whole-body of fish was not significantly (P>0.05) affected by either feed or salinity. However, lipid and ash content of the whole-body of fish was significantly (P<0.05) affected by salinity, but not by feed. In conclusion, the MP was superior to CF for growth of sunshine bass during the winter season in Korea and no mortality occurred. And sunshine bass seemed to grow better in freshwater $(0\%)$ and brac-kishwater $(15\%)$ than seawater $(32\%)$ under these experimental conditions, in terms of improvement in FER and PER in freshwater or brackishwater.

• Korean Journal of Microbiology
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• v.29 no.5
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• pp.339-343
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• 1991

Heterotrophic activity, total bacteria and salinity were determined seasonally in the estuary of Naktong River over half tidal cycle. Heterotrophic activity was determined by the uptake of [U- $^{14}$ C]glucose. Heterotrophic activity fluctuated with the tides and was decreased as salinity increased. Teh great activity occurred near low ebb tide at all seasons except summer. The main environmental factor affecting hetreotrophic activity was the salinity rather than water temperature in the estuary of Naktong River. In order to estimate the effect of salt, salt was added to estuarine water. Vmax for glucose of salt-added water was 17% and 77% of original estuarine water at station 1 and 2 respectively and slight increase was observed at station 3. Respiration rate and Kt+Sn for glucose of salt-added sample increased at all 3 stations. The increase of the Kt value implies the reduced affinity of bacterial population for glucose. The effects of salinity on the heterotrophic activity were more extensive in the upper region of estuary than at the mouth.