• 한국지구물리탐사학회:학술대회논문집
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• 2007.06a
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• pp.307-312
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• 2007

Seawater intrusion in estuarine regions is an important issue in protecting groundwater against salinity increase as well as in protecting construction materials against corrosion. For example, drain water ejected during accelerated consolidation for the improvement of soft ground can cause damages to farm land because the drain water from seawater intrusion zones contains salinity. In this study, we have employed correlation analysis between resistivity value and salinity of in situ pore water. The correlation analysis indicates that resistivity and salinity are in exponential relationship with good correlation. Therefore we suggest that rapid estimation of spatial distribution of NaCl is possible using resistivity data.

• The Korean Journal of Malacology
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• v.26 no.3
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• pp.171-177
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• 2010

We examined physiological responses related to the survival, oxygen consumption and filtration rate of the blood cockle, Tegillaarca granosa as a result of salinity changes. The 44-day $LS_{50}$ (median lethal salinity) at $10^{\circ}C$ for adult and juvenile was 15.8 (confidence limits 13.5-18.2 psu) and 16.2 (confidence limits 14.1-18.4 psu) psu respectively, whereas the 11-day $LS_{50}$ at $25^{\circ}C$ for adult and juvenile was 16.8 psu (confidence limits 12.9-21.2 psu) and 22.4 (confidence limits 20.5-24.7 psu) psu respictively. In conditions of decreasing salinity, Oxygen consumption and filtration rates decreased or varied irregularly as salinity decreased. The results of this study could prove important in investigating causes of mass mortality and managing shellfish aquaculture farms.

• Journal of The Korean Society of Agricultural Engineers
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• v.57 no.4
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• pp.113-120
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• 2015

The objectives of this study were to monitor and assess the effects of saline irrigation water on lettuce and carrot growth in protected cultivation. One control and 4 treatments with three replications, 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 results showed that the use of irrigation water containing above a certain level of salinity was found to cause excessive accumulation of salts in the soil as saline irrigation water increased electrical conductivity (EC) and sodium ($Na^+$) content in both lettuce and carrot soil samples, while tap water irrigation used as control decreased the salinity in the samples. The salinity higher than the threshold level of irrigation water was found to reduce the yields of lettuce and carrot, while in less than the threshold level the higher the salinity of the irrigation water increased the yields. The salinity of the irrigation water also appeared to increase the internal salinity of the plant as the $Na^+$ content in plant increased as the salinity of irrigation water increase. Increased $Na^+$ content was analyzed to be able to increase the sugar content in carrot. This study could contribute to suggest water quality criteria for safe use of saline water in protected cultivation, although long-term monitoring is needed to get more representative results.

• Journal of Environmental Health Sciences
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• v.27 no.3
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• pp.21-26
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• 2001

This study was performed to define the physicochemical characteristics of food waste and food wastewater, and to find the effect of salinity variation experiment, the samples of 1, 2, 3 and 4 were prepared by the salinity of 1.0%, 1.5%, 2.0% and 2.5%, respectively. In experiment, aerobic composting reactors were operated by the model which was composed of half an hour's stirring and 2 hour's aeration per day, for 45 days. Seeds of vegetables of Chinese cabbage and red pepper were seeded at compost-free control, compost 1, 2, 3 and compost 4 for the sake of investigation of germination rate and growth rate of those. The followings are the conclusions that were derived from this study. 1. In food waste, the moisture content was 60%, organic compound content was 95%, total carbon was 47.5%, total nitrogen was 1.6%(therefore, C/N ratio was 30). The values of pH were 4.0 and 3.8 the values of salinity were 0.9% and 1.2%, and the values of conductivity were 7.8 mS/cm and 18.0 mS/cm, respectively. 2. In salinity experiment, the reduction rate of volume was increased(40%) when the salinity was decreased(1.0%). Also, the reduction rate of mass was increased(52%) when the salinity was decreased(1.0%). This fact denotes that salinity hinders the process of composting. 3. Germination rate and growth rate of Chinese cabbage are more excellent than those of red pepper(97.14%, 5.2:2.5 cm). 4. In Chinese cabbage, germination rate and growth rate at compost with the lowest salinity are more excellent than those at compost-free control(97:94%, 5.2:4.5 cm).

• Korean Journal of Environmental Biology
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• v.21 no.1
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• pp.66-71
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• 2003

Effects of salinity on survival, growth and oxygen consumption rates were examined in the mysid, Neomysis awatschensis. Mysids were exposed to various concentrations of salinity (0, 3.4, 6.7, 10.1, 13.4, 20.2, 27.4 and 33.6$\textperthousand$) for 40 days. Survival rate was significantly declined at below 6.7$\textperthousand$ after 40 days. Body length and daily growth rate of mysids exposed at below 6.7$\textperthousand$ salinity were significantly decreased than those of mysids exposed at above 10.1$\textperthousand$ salinity. Oxygen consumpiton rate of mysid exposed at salinity raining of 10.1~39.6$\textperthousand$ during 40 days not greatly changed in comparison with that before salinity treatment, but that of mysid exposed at below 6.7$\textperthousand$ significantly decreased. These results indicated that low salinity concentration ($\leq$6.7$\textperthousand$) reduced survival, growth and oxygen consumption rates of the mysid suggesting potential influence on the natural mortality of Neomysis awatschensis in the estuarine and coastal areas.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.5
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• pp.712-718
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• 2015

The effects of salinity on survival, oxygen consumption, and hematological response of greenling Hexagrammos otakii, mean body weight 147.1±3.8 g, were investigated under salinity conditions of 33.4 (control), 33.1, 32.8, 32.2, 31.0, 28.7, 23.9, 14.5, and 3.8 psu, to evaluate physiological effects in relation to changes in salinity. The survival and hematological responses of fish were measured at each salinity after 96- and 24-h exposures. The oxygen consumption rate (OCR) of fish was measured in triplicate under conditions of stepwise salinity exposure (33.4→33.1→32.8→32.2→31.0→28.7→23.9→14.5→3.8 psu) with an interval of 24 h at each salinity, using a continuous flow-through respirometer. No fish mortality was observed in the range of 33.4 to 14.5 psu, but the survival rate was reduced to 53.3% at 3.8 psu after 96 h of exposure. The OCRs did not significantly differ in the range between 33.4 to 28.7 psu (P>0.05), but significantly increased at 23.9 and 14.5 psu, and then dramatically decreased at 3.8 psu compared to the control (P<0.05). Hematological variables, such as glucose, glutamic pyruvic transaminase (GPT), hematocrit, and Na⁺, were affected by reduced salinity. This result may be applicable for habitat and culture management of greenlings.

• Journal of Environmental Science International
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• v.18 no.10
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• pp.1171-1179
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• 2009

The solitary ascidian, Halocynthia aurantium, which is commonly called the sea peach because of its coloration and general shape, is a valuable organism of benthic marine population in the northern region of the East Sea, Korea. It is seldom found at a depth of less than 10 meters and the sea peach is frequently observed in large populations between 20 and 100 meters. It appears to prefer attachment to vertical rocks faces and artificial cement blocks exposed to the currents. Mass mortality and reduction of resources in sea peach, H. aurantium, were occurred in the benthic area of the northern region of the East Sea because of the rapid fluctuation of environmental factors such as temperature and salinity due to mass rainfall in summer and going up north of a strong warm current in winter. Therefore, we examined the effects of temperature and salinity on embryonic development of fertilized eggs, tadpole larva to metamorphosis, and attachment to siphon development. Laboratory-raised larvae were studied using a two-factorial experimental design with four levels of temperature(8, 12, 16 and $20^{\circ}C$) and four levels of salinity(20, 25, 30 and 34 psu). The ascidian larvae of H. aurantium survived environmental conditions between temperature of $8{\sim}20^{\circ}C$ and salinity of 25~34 psu and exhibited positive growth at $8{\sim}16^{\circ}C$ and 30~34 psu. Fertilized eggs have not developed at lower salinity of 20 psu irrespective of temperature range tested and have showed an abnormal development at the salinity of 25 psu between higher temperatures of 20 and $24^{\circ}C$. This result suggests that temperature increase and salinity reduction depending on environmental fluctuation may have significant impacts on population variation of H. aurantium in the northern region of the East Sea.

• Fisheries and Aquatic Sciences
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• v.9 no.4
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• pp.153-159
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• 2006

The ark shell (or 'blood clam') Scapharca broughtonii is a filter-feeding bivalve that has red blood and inhabits waters approximately 10m in depth off the southern coast of South Korea. This study was part of a larger research project investigating the causes of death and restoration of shellfish resources, which are important aquaculture products in South Korea. We examined physiological responses related to survival, respiration, excretion, and amino acid changes as a result of changes in salinity. The 9-day median lethal salinity ($LS_{50}$) was 16.5 psu with confidence limits of 14.9-18.1 psu. At $25^{\circ}C$, the oxygen consumption and ammonia-nitrogen excretion rates were increased with decreases in salinity. Although the osmolality of individuals was acclimated within 2 h at 26.4 psu and 12 h at 19.8 psu, it took more than 5 days at a salinity of 13.2 psu, whereas no individuals acclimated and all died at a salinity of 6.6 psu. Of the amino acids present in the blood, taurine and alanine increased in response to decreased salinity. Tissues of the gill and the mid-gut gland were affected by decreasing salinity. These data will provide important fundamental information for examining the causes of mass mortality of shellfish in the summer.

• The Korean Journal of Ecology
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• v.12 no.4
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• pp.219-236
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• 1989

The effect of salinity on the seed germination and seedling growth of Pinus densiflora for. erecta Uyeki were studied under the controlled conditions in the growth chamber. The seeds were sorted into three classes in weight such as large ($15.49\pm$1.63mg), medium($10.61\pm$1.38mg), and small ($6.57\pm$1.33mg) to determine the role of seed weight in germination and seedling growth of the pine. Polymorphic seeds of the pine were germinated an salinity range of 0 to 1.5% NaCl under various temperature ($10^{\circ}$ $-25^{\circ}$ with $5^{\circ}$C interval of constant temperature, and $10^{\circ}$ $-20^{\circ}$C, $15^{\circ}$ $-25^{\circ}$C of alternating temperature) in order to determine their germinability and seeding growth. In control plot, there was little difference of germination percentage among the seed weight classes, but in saline plot, the larger seeds generally had a higher percentage and rate of germination. There occurred synergistic interaction between salinity and temperature in the germination and the increase of temperature enhanced germination of seeds at the same salinity level. Alternating temperature regimes of $15^{\circ}$-$25^{\circ}$C yielded maximum germination and no germination was occurred at $10^{\circ}C$. The germination at alternating temperature showed higher germination percentage than at constant temperature. The percentage and of germination decreased drastically with increased salinity level to 1.00%; no germination was occurred at 1.50% salinity level. The growth fo sddelings from larger seeds was better than that of smaller seeds at the same salinity and temperature. The hypocotyl and radicle were more sensitive than cotyledon to the increased salinity stress.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.11
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• pp.1729-1737
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• 2007

A CRD experiment was conducted to evaluate the effects of different exogenous betaine levels (0.000, 0.075, 0.150 and 0.225 percent) on 576 one-day-old male broiler chicks (Ross) under water salinity stress. Different levels of water salinity were made by adding 3 levels of NaCl (0, 1,000 and 2,000 mg/L) to drinking water. Feed and water were available ad libitum. Betaine increased body weight, improved feed conversion ratio, and decreased packed cell volume (p<0.05). Water salinity promoted body weight over the whole period, increased feed intake (11 to 21 and 29 to 42-d) and also improved feed conversion ratio in grower and finisher periods (p<0.01). Breast weight, water consumption (28-d and 42-d) and excreta moisture (28-d) were increased by elevating the level of water salinity (p<0.01). Interaction between dietary betaine and water salinity was significant on plasma osmolarity as well as epithelial osmolarity of the duodenum at 28-d. Epithelial osmolarity was decreased from duodenum to ileum. The data imply that betaine is involved in the protection of intestinal epithelia against osmotic disturbance which can be caused by saline water, but further research is needed to investigate the effects of betaine with higher levels of water salinity.