• Proceedings of the Korean Aquaculture Society Conference
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• 한국양식학회 2004년도 수산관련학회 공동학술대회 발표요지집
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• pp.252-253
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• 2004

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 한국어업기술학회 2003년도 춘계 수산관련학회 공동학술대회발표요지집
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• pp.244-245
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• 2003

한국의 내수면 어류양식은 송어, 틸라피아 및 잉어류가 주류를 이루고 있으나 과잉생산으로 인해 경제성이 낮으며, 최근 수입개방과 환경오염으로 담수양식 산업이 어려움에 처해 있는 실정이다. 따라서 새로운 고가의 양식어종 개발은 내수면 어류양식에 있어 시급히 해결해야 할 중요한 과제이다. 이러한 문제를 해결하기 위하여 최근에 광염성 해산어류의 뛰어난 삼투압 조절능력을 응용한 감성돔의 담수순화 양식이 시도되고 있다. (중략)

• Korean Journal of Microbiology
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• 제49권1호
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• pp.38-45
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• 2013

In this study, euryhaline marine microorganism, Bacillus sp. strain EBW4 isolated from polychaete (Perinereis aibuhitensis) of Suncheon Bay was physiologically, biochemically and genetically characterized. Based on 16S rRNA sequence, EBW14 was found to share 98.25% similarity with Bacillus hemicentroti $JSM076093^T$, 97.96% similarity with Bacillus hwajinponensis SW-$72^T$ and 96.28% similarity with B. algicoa $KMM3737^T$, respectively. The temperature range for the growth of strain EBW4 was $4-40^{\circ}C$, NaCl concentration range 0-17% and pH range pH 5-9, revealing that EBW4 was euryhaline bacterium. Major fatty acids in strain EBW4 were composed of anteiso $C_{15:0}$ (48.2%), iso $C_{16:0}$ (12.1%), anteiso $C_{17:0}$ (11.6%) and iso $C_{14:0}$ (9.4%). EBW4 was found to have DNase, amylase, protease and lipase for the degradation of macromolecules such as DNA, carbohydrates, proteins, lipids, etc. The enzyme activities of alkaline phosphatase, esterase (C4), leucine arylamidase and ${\alpha}$-chymotrypsin were also found in strain EBW4. Analysis of the biodegradation ability of EBW4 for organic hydrocarbons under different salinity conditions using synthetic water waste revealed that EBW4 exhibited the ability to degrade organic hydrocarbons very quickly, suggesting strain EBW4 may be a good candidate for the application to various industries.

• Korean Journal of Ichthyology
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• 제22권1호
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• pp.25-33
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• 2010

Effects of different salinity levels on spawning performance, embryonic development and early viability of a euryhaline medaka species, Oryzias dancena, were examined. O. dancena were able to spawn eggs in a wide range of salinity from 0 to 70$^{\circ}/_{\circ\circ}$, however, the spawning frequency was lowered in complete freshwater (0$^{\circ}/_{\circ\circ}$) and in highly salted water (70$^{\circ}/_{\circ\circ}$). Fertilization success was negatively affected when the environmental salinity was higher than the salt concentration found in normal seawater. Embryonic viability and hatching success were also inversely related with the salinity levels. Typical abnormality was observed in developing embryos incubated at high salinities (30, 45 and 60$^{\circ}/_{\circ\circ}$). In addition, the time to hatch was significantly delayed with increasing salinities: peak hatching occurred at 12~14 days post fertilization (dpf) in freshwater and at least at 17 to 18 dpf in 60$^{\circ}/_{\circ\circ}$. Mean survival rates of the hatched larvae up to 7 days post hatching (dph) were at least 97% in salinity levels ranging from 0 to 30$^{\circ}/_{\circ\circ}$. However, larvae reared in 45 and 60$^{\circ}/_{\circ\circ}$ experienced significant mortality, especially in the early phase, resulting in only 75% and 64% survival rates up to 7 dph, respectively.

• Korean Journal of Microbiology
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• 제26권3호
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• pp.256-261
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• 1988

Samples from Naktong Estuary had been taken for the characterization of heterotrophic bacterial communities and of the effects of environmental factors on their distribution in estuarine ecosystem. Bacterial communities isolated from seawater region were composed of more euryhalone groups than those from freshwater region, and the bacterial communities of summer were composed of more eurythermal groups than those of winter. Bacterial commnities became more diverse by the input of allochthonous bacteria from terrestrial and freshwater ecosystem, but less diverse by worse environmental conditions such as nutrient load, high salinity, low temperature, and so on.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 한국방사성폐기물학회 2011년도 추계학술논문요약집
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• pp.453-454
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• 2011

• Korean Journal of Ichthyology
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• 제32권2호
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• pp.84-90
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• 2020

We investigated carbon and nitrogen isotope ratios (δ¹³C and δ¹⁵N) of the slipmouth Leiognathus nuchalis to reveal the effects of body size, feeding strategy and spatial distribution on the food resource utilization during the migration in the Seomjin estuary and Gwangyang Bay. The δ¹³C values of L. nuchalis caught in the Seomjin estuary where the salinity is lower than 30 psu were much lower than those in the deep-bay area of Gwangyang Bay. Such a spatial heterogeneity in δ¹³C values of the L. nuchalis clearly indicates active feeding within the estuarine habitat. In contrast, the δ¹⁵N values of L. nuchalis showed a consistency among sites, indicating that this species occupies identical trophic level across the whole area. The slipmouth distributed throughout the bay area, reflecting its euryhaline characteristics. However, the distribution pattern appeared to be separated according to body size into smaller individuals in the low-saline estuary and larger ones in the deep bay. Overall results support the plastic feeding strategy of the slipmouth from zooplanktonic (estuarine habitat) to epibenthic (deep-bay habitat) feeder during the migration between estuarine to deep-bay habitats.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 한국해양공학회 2006년 창립20주년기념 정기학술대회 및 국제워크샵
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• pp.469-472
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• 2006

The primary objective of this study was to gain insight into the characteristics of algal blooms in relation to the marine environment of the Korean Southern Coast, using more than 22 years worth of data since the first known occurrence of algal blooms. Algal blooms tend to occur when the precipitation or water temperature for a ten-day period prior to the annual bloom exceeds the long-term mean value. There are three notable causative species in six different inner bays, namely Prorocentrum sp., Skeletonema costatum, and Heterosigma akashiwo, and in addition, these three species appeared in different conditions of water temperature and salinity at each region.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 한국어업기술학회 2001년도 추계 수산관련학회 공동학술대회발표요지집
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• pp.287-288
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• 2001

해산어류의 담수순화에 관한 연구는 일부 광염성 어종에 대해 수행되어 왔으나, 극히 미비한 실정이다 담수순화에 관한 연구는 아가미 구조적 연구, 내분비학적 연구 등이 연어과 어류의 회유시에 밝혀진 바 있다(Chen and Lin., 1994). 다른 해산어류의 삼투압조절 등 생리학적 연구는 숭어의 담수사육에 관한 기초연구 결과가 보고(장과 허, 1999)되고 있다. 그러므로 이러한 삼투압조절 능력 등이 실제 산업에 이용되려면 각각의 양식유용종에 대한 상세한 연구와 각 어종의 염분 내성, 삼투압조절 능력, 염분변화에 따른 생존 및 성장 그리고 삼투압조절 기능을 향상시키기 위한 물리적, 화학적, 생리학적 연구 등이 필요하다. (중략)

• Korean Journal of Ichthyology
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• 제22권1호
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• pp.9-16
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• 2010

Osmoregulatory capabilities of a euryhaline medaka, Oryzias dancena (Beloniformes; Teleostei), was examined with a particular emphasis on adult and larval viability during direct salinity changes. O. dancena adults were highly capable for hyper-osmoregulation as well as hypo-osmoregulation, as evidenced by no adverse effect on their viability during the direct transfer either from complete freshwater ($0^{\circ}/_{\circ\circ}$) to $40^{\circ}/_{\circ\circ}$ salinity, or from $70^{\circ}/_{\circ\circ}$ to $0^{\circ}/_{\circ\circ}$. Furthermore, the phased increase of external salinity with acclimation periods allowed them to survive at a salinity as high as $75^{\circ}/_{\circ\circ}$. However, tolerant capability to acute salinity increase in early larval stage was much less than in adult stage, based on the finding that the tolerance range of salinity increase was only $15^{\circ}/_{\circ\circ}$ from freshwater, indicating that the hyper-osmoregulation system might not be fully developed in the early larval stage. On the contrary, the hypoosmoregulation system could be more solidified in O. dancena larvae, as evidenced by their good survival even after direct transfer from $45^{\circ}/_{\circ\circ}$ to $0^{\circ}/_{\circ\circ}$. Knowledge achieved in this study could form the basis for a wide scope of researches including ecotoxicogenomics and geneexpression assay using this model species.