• 한국어병학회지
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• 제15권3호
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• pp.111-115
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• 2002

The scuticocilliate, Uronema marinum is a histophagous ciliate and the causative agent of 'scuticociliatosis'in cultured olive flounder Paralichthys olivaceus. In the present study, in vitro efficacy of hydrogen peroxide, formalin and copper sulfate on the scuticocilliate at low salinity was investigated. Each chemical showed synergistic parasiticidal effects with low salinity (salinity in 5 ppt) compared to each chemical alone (salinity in 33 ppt). At low salinity (5‰), ciliates were killed completely within 1.5h by exposure to 50ppm formalin (37% formaldehyde), at 100ppm hydrogen peroxide (30% solution) and at 100ppm copper sulfate (20% solution). The formalin was the most effective chemical against the parasites at low salinity.

• Fisheries and Aquatic Sciences
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• 제15권2호
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• pp.177-181
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• 2012

To understand the effects of lower pH levels due to elevated $CO_2$ and salinity, we designed and constructed a pH-control system that included automatic $CO_2$ infusion and measured the hatching rate of a crustacean model species, Artemia franciscana. The pH-control system was cost-effective and capable of performing animal tests in which pH fluctuated around $8.0{\pm}0.1$, with the temperature around $27{\pm}0.5^{\circ}C$. Hatching rate was observed under four different pH levels (7.0, 7.3, 7.6, and untreated control) combined with three salinity ranges (15, 25, and 35 ppt). The results demonstrated that lower pH levels led to decreased hatching rates regardless of salinity, and the minimum hatching rate was detected at pH 7.0 compared to the control (pH $8.0{\pm}0.1$), supporting the idea that OA has adverse effects on hatching rates and increases the risk of juveniles being introduced in the ecosystem. In contrast, salinity changes exhibited no synergistic effects with pH and had independent effects.

• Fisheries and Aquatic Sciences
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• 제8권2호
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• pp.70-75
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• 2005

We investigated the effects of salinity and three food species of microalgae on the growth of three types of the rotifer Brachionus plicatilis, with the aim of improving mass culture of rotifers in hatcheries. Three types (large, small, and ultra-small) of the rotifer were cultured at 16 ppt and 32 ppt salinity with the green algae Chlorella ellipsoidea, Nannochloris oculata, or Tetraselmis tetrathele. The maximum density and specific growth rate were compared for each rotifer type. Ultra-small rotifers grew significantly faster at 16 ppt salinity than at 32 ppt, and C. ellipsoidea and T. tetrathele promoted significantly higher growth than did N. oculata. However, small rotifers grew significantly better at 32 ppt salinity than at 16 ppt, and small rotifers fed on N. oculata achieved the highest density at 1,185 individuals/ml. Large rotifers grew faster at 16 ppt salinity than at 32 ppt, with a diet of T. tetrathele resulting in the fastest growth. Each type of rotifer thrived under different regimens of microalgae and salinity.

• Journal of Plant Biology
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• 제36권3호
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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.

• 한국농공학회논문집
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• 제57권4호
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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.

• 한국수산과학회지
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• 제48권5호
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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.

• 산업기술연구
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• 제27권B호
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• pp.29-36
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• 2007

A comparative study of airborne salinity and sea wind was done for a coastal area, Sokcho city, of East Sea in Kangwon province, Korea. In this study, a relationship between the formation of airborne salinity and wind velocity was investigated, and then the airborne salinity was simulated and forecasted by the obtained wind-salinity characteristics. It is founded that most airborne salinity is brought by sea winds with the occurrence of velocity, higher than and equal to 4m/s, while the occurrence of lower wind velocities (ie., lower than 4m/s) in sea wind and the occurrence of inland wind give diluted effects on the airborne transfer. By using these characteristics and a proposed linear equation model, the salinity in Sokcho city is successfully simulated and forecasted. It is expected that the linear equation model may be useful for durability design of concrete structures under the conditions of chloride attack, induced by the airborne salinity.

• 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.

• 한국작물학회지
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• 제28권3호
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• pp.299-304
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• 1983

간척지에서 생육된 수도의 근군형성양상을 조사하기 위해 염해의 정도가 서로 다른 3구에서, 시료를 채취하여 다음과 같은 결과를 얻었다. 1. 고염지에서 생육한 수도의 근군은 저염지에서 생육된 수도의 근군보다 천근성을 나타냈다. 2. 고염지에서 생육된 수도의 근군을 구성하는 관근수는 저염지에서 생육된 수도의 근군을 구성하는 관근수보다 적었다. 3. 각 요소에서 출근된 관근수도 고염지에서 생육된 수도가 저염지에서 생육된 수도보다 적었으며, 이와 같은 현상은 이앙후 출근하는 요소에서부터 나타났다. 4. 각 처리구의 관근에 형성된 분지근의 밀도는 고염지에서 생육된 수도가 저염지에서 생육된 수도보다 높은 경향을 나타냈다. 5. 각 처리구의 관근에 형성된 근모의 형성양상은 고염지에서 생육된 수도가 저염지에서 생육된 수도에 비하여 근모형성율이 낮고 또 근모장도 짧은 경향을 나타냈다.

• Asian-Australasian Journal of Animal Sciences
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• 제20권11호
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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.