• 한국수산과학회지
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• 제38권1호
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• pp.12-19
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• 2005

This study investigated the productivity and growth of copepods, Sinocalanus tenellus 2 strains, Paracyclopina nana 3 strains, Apocyclops royi 2 strains, Tachidius triangularis 1 strain and Tigriopus sp. 1 strain at different temperatures $(24,\;28\;and\;32^{\circ}C)$ under 15 psu and various salinities (10, 20, 30 psu) at $28^{\circ}C$ for an individual culture. And the mass culture was carried out to evaluate the production of these copepods in the 500 mL vessel. For an individual culture of copepod, survival period of a brood female tended to increase with the decrease of temperature, but was not significantly influenced by salinity. With an increase of temperature and a decrease of salinity, maturation period of nauplii in all species tended to decrease. Total nauglii production from a broodo female at $24^{\circ}C$ was higoher than that from a brood .female at either 28 or $32^{\circ}C$ for S. tenellus and at $32^{\circ}C$ than either 24 or $32^{\circ}C$ for A. royi Haenam stram, but was not influenced by temperature for another copepods. And total nauplii production from a brood female at 10 and 20 psu tended to be higher than that from a brood female at 30 psu, expect for Tigriopus sp. and P. nana Hwajinpo strain. Total nauplii production from a brood female was the highest in Tigriopus sp. (350 nauplii) at $28^{\circ}C$ under 20 psu, followed by A. royi Haenam strain (187 nauplii) at $32^{\circ}C$ under 15 psu and P. nana Hwajinpo strain (152 nauplii) at $24^{\circ}C$ under 10 psu. In the mass culture of each copepod, P. nana was the most productive (26.6 mg dry weight) and this value was two and four times higher than productivity of Tigriopus sp. and A. royi, respectively.

• 수산해양교육연구
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• 제27권2호
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• pp.526-536
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• 2015

대왕바리, Epinephelus lanceolatus의 담수순화 방법에 따른 산소소비 경향을 조사하였다. 염분 변화 조건은 대조구인 35 psu (Exp. I) 외에 단계적 염분변화 조건인 Exp. II($35{\rightarrow}20{\rightarrow}10{\rightarrow}0$ psu)과 Exp. III ($35{\rightarrow}10{\rightarrow}0$ psu) 그리고 급격한 염분변화 조건인 Exp. IV ($35{\rightarrow}0$ psu)로 하였다. 염분 저하 방법별로 산소소비량을 측정한 결과, 수온 $27^{\circ}C$에서 실험어의 평균 산소소비량은 Exp. I에서 $106.9{\pm}0.7mg$ $O_2/kg/h$였다. Exp. II에서는 염분이 $35{\rightarrow}20{\rightarrow}10{\rightarrow}0$ psu로 낮아지면서 각각 $108.1{\pm}2.1$, $99.6{\pm}2.9$, $74.6{\pm}0.9$ 및 $62.7{\pm}1.0mg$ $O_2/kg/h$, Exp. III에서는 각각 $106.5{\pm}1.3$, $77.0{\pm}1.2$ 및 $64.7{\pm}1.2mg$ $O_2/kg/h$로 감소하였다. Exp. IV 역시 산소소비량은 35 psu의 $109.0{\pm}0.9mg$ $O_2/kg/h$로부터 0 psu의 $71.6{\pm}2.0mg$ $O_2/kg/h$로 감소하는 경향을 보였다. 대왕바리는 모든 실험 조건에서 암기 보다 명기에 많은 산소소비량을 보여, 주행성 어종인 것으로 추정되나, 명기와 암기의 산소소비량은 큰 차이를 보이지 않았다. 이상의 결과를 종합해 볼 때, 대왕바리 치어는 염분 저하 방법별 산소소비량에서 서로 차이를 보이지 않아 저염분 순화에 있어 생리적 문제는 발생하지 않았으며, 실험과정 중 폐사한 개체도 없었다. 따라서 대왕바리는 염분변화에 매우 강한 광염성 어종이며, 담수환경에 쉽게 적응할 수 있을 것으로 판단된다.

• 한국양식학회지
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• 제21권2호
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• pp.70-75
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• 2008

본 연구는 입이 작은 어류들의 초기 먹이생물로 이용 가능성이 있는 초소형 rotifer Synchaeta kitina의 대량배양을 위한 최적 염분 및 수온을 규명하는데 그 목적이 있다. S. kitina를 대상으로 6개(5, 10, 15, 20, 25 및 30 psu)의 염분구와 5개(16, 20, 24, 28 및 $32^{\circ}C$)의 수온구를 두어 이들의 성장을 비교해 보았다. 이 때 모든 실험은 밀집 및 개체배양으로 나누어 행하였다. 염분 및 수온에 따른 실험결과, 밀집배양 시 최고밀도는 저온, 저염분 일 때 높은 경향을 5 psu, $16^{\circ}C$에서 유의적으로 가장 높게 나타났다. 또한 개체배양을 통한 생식 전 단계, 순 생식 단계, 산란수 및 수명 등의 성장요인들도 저온, 저염분 일수록 유의적으로 높게 나타나는 것으로 조사되었다. 따라서 초소형 rotifer S. kitina의 대량배양을 위한 최적 염분 및 수온 조건은 밀집배양 시 최고밀도를 보이고, 개체배양 시 생식, 평균수명과 같은 성장요인이 유의적으로 높게 나타난 5 psu, $16^{\circ}C$라 판단된다.

• 한국패류학회지
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• 제21권1호
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• pp.13-17
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• 2005

In this study, the influence of water temperature and salinity on sand ejection of Manila clams, Ruditapes philippinarum, was investigated. The result showed that, under different water temperature, the highest quantity of sand ejection was at $20^{\circ}C$, the value of which was 0.091 g, while the smallest one was only 0.058 g at 0$^{\circ}C$. The highest releasing rate, 95.79%, could be seen in $20^{\circ}C$ group, while $0^{\circ}C$ group was the lowest one, 85.29%. Under different salinity, 30 psu group had the highest value, 0.057 g, and 0 psu (freshwater) group was the lowest one, only 0.026 g. At the same time, the highest releasing rate appeared at 25 psu, which was 90%. 0 psu group was the lowest one in releasing rate, 60.47%. According to these results, we recommend that the clams should be placed into the clear seawater with about 25 psu of salinity at near $20^{\circ}C$ to let the clams perform the self-depuration. Better quality of clams containing less impurity in the aquaculture and commerce could be obtained from this pre-treatment.

• The Journal of Asian Finance, Economics and Business
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• 제9권3호
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• pp.377-388
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• 2022

The Personal sense of uniqueness (PSU) is positively associated with subjective well-being and has been recently shown its correlation with happiness, influencing consumer's experience behavior. However, the effects of hedonic and eudaimonic experience on conspicuous and inconspicuous (consumer's need for status and inner fulfillment) are unknown. The purpose of this research is to address a gap existing in the literature by testing the effects of PSU on hedonic and eudaimonic leisure experiences and how happiness leisure experiences effects conspicuous and inconspicuous consumption. The relationships hypothesized in the model are tested using partial least squares structural equation modeling (PLS-SEM) and bootstrapping procedure. Data was gathered using a self-administrated survey, answered by 200 consumers based on consumers' leisure experiences. The findings of this study suggest that (i) PSU positively and significantly influence hedonic and eudaimonic happiness; (ii) the effect of PSU on eudaimonic happiness is higher than in hedonic happiness; (iii) eudaimonic happiness positively and significantly influence conspicuous and inconspicuous consumption; and (iv) hedonic happiness negatively and significantly influence conspicuous and inconspicuous consumption. This study helps fill a gap in the literature by introducing and testing the effect of hedonic and eudaimonic leisure experiences and the relationship between these constructs and PSU and (in) conspicuous consumption.

• ALGAE
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• 제19권2호
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• pp.145-148
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• 2004

As a result of the 2-year monthly monitoring of the phytoplankton community at 3 stations in Mankyeong Estuary, Korea, we learned that cyan bacterial species of the genus Anabaena occurred at most sampling points with huge salinity differences (0.1-32.5 psu). We isolated several clones of Anabaena spp. from the monitoring stations, and screen out two euryhaline and nitrogen-fixing Anabaena clones, CB-MAL21 and CB-MAL22. The two clones were grown under various environmental gradients such as temperature (20, 30, 35 and 40$^{\circ}C$), salinity (0, 2, 5, 15 and 30psu), and $PO_4^{3-}$-P concentration (0, 1.6, 8.0, 40 and 200 ${\mu}M$M). Growth of CB-MAL21 and CB-MAL22 was measured by daily monitoring of chlorophyll fluorescence from each experimental culture for more than three serial transfers. Both the two experimental clones did not grow at 0psu. Maximal growth rates of the two clones were markedly reduced at lower $PO_4^{3-}$-P concentrations showing negligible growth at 0 and 1.6 ${\mu}M$M. However, growth of CB-MAL21 was not affected by low $NO_3^--$ concentration in culture media, showing the nitrogen-fixing ability. Maximum biomass yields of the two clones decreased dramatically at 35 and 40$^{\circ}C$. Optimal growth conditions for the two experimental clones were determined to be 20-30$^{\circ}C$, 40 ${\mu}M$M $PO_4^{3-}$-P, and wide salinity range from 5.0 to over 30psu. Best growth of CB-MAL21 was shown at (20$^{\circ}C$-15psu), which is less saline and cooler condition than those (i.e., 30$^{\circ}C$-30psu) for the best growth of CB-MAL22. The euryhaline and nitrogen-fixing CB-MAL21 strain thus can be a candidate laboratory culture for the future cyan bacterial marine biotechnology in temperate coastal waters.

• 한국발생생물학회지:발생과생식
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• 제15권2호
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• pp.151-158
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• 2011

장기간 담수순화 사육한 감성돔 Acanthopagrus schlegelii(BFW) 정액의 화학적 특성과 염분 및 이온조성에 따른정자활성을 해수사육 감성돔(BSW) 정액과 비교하였다. BFW 정장의 화학적 특성은 대부분의 요인에서 BSW 정장과 차이를 보이지 않았으나, 삼투질농도는 각각 $307.0{\pm}4.6$, $337.3{\pm}10.1$ mOsm/kg으로 차이를 보였다. 염분에 따른 BFW 및BSW의 정자운동성는 0 psu에서는 운동성이 관찰되지 않았으나, 10 psu에서 낮은 운동성과 짧은 정자 운동지속시간을 보였다. 그러나 20, 32 psu에서는 높은 운동성과 긴 정자 운동지속시간 보였다. BFW와 BSW 정자의 SAI는 이온의 종류와는 상관없이 삼투질농도에 의존하여 변화하였으며, 인공해수와 비슷한 농도에서 높았다. 결론적으로 장기간 담수에서 사육한 감성돔의 정자의 운동개시요인은 환경수의 삼투질농도가 좌우하는 것으로 판단된다.

• 한국수산과학회지
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• 제38권5호
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• pp.331-341
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• 2005

Distribution of anchovy (Engraulis japonica) eggs and larvae was studied in the southwestern sea of Korea in July and November, 2001. Anchovy eggs were found mainly in the oceanic fronts of the northern sea area which were formed in the offshore area of Chuja Is. Bogil Is. and Chungsan Is. from west to east. Anchovy eggs were also found in the surrounding sea of Cheju Is. in the southern sea front area. The waters were highly heterogeneous and the water masses were bordered based on temperature $(10.8-26.4^{\circ}C)$ and salinity (28.9-33.7 psu). The anchovy eggs were mostly found outside of the China Coastal Water, where salinity was below 31 psu. The anchovy eggs were not found in November. Abundance of the anchovy larvae were higher in July than November. Temperature ranged from $10.8^{\circ}C\;to\;25.9^{\circ}C\;and\;15.9^{\circ}C\;to\;20.5^{\circ}C$, and salinity ranged from 28.9psu to 34.1psu and 33.2psu to 34.1psu in July and November, respectively. Non-swimmable larvae were found throughout the whole area of the southwestern sea of Korea. The area beyond the oceanic front had anchovy eggs dispersed from the spawning grounds to offshore. Dispersion pattern showed that the eggs were transported from the spawning grounds with a process of advection and diffusion based on the flow pattern which were caused by winds. Distribution pattern of the anchovy eggs and larvae may be used for the prediction of oceanic currents in each area.

• Journal of the korean society of oceanography
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• 제38권4호
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• pp.211-215
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• 2003

A huge freshwater reservoir (ca. 12,000 ha) will be created when the construction of a 33­km dike on a huge mud flat of the Saemankeum areas is established. A large quantity of freshwater will emerge to the adjacent sea from the reservoir through two big gates. Marine organisms outside the dike are expected to frequently experience low salinity waters. To investigate the salinity effects on the dominant metazooplankton in the coastal waters off Saemankeum areas, we measured the survival (Survival 1H and Survival 24H) of 11 different taxa (the copepods Acartia omorii, A. pacifica, Calanus sinicus, Centropages abdominalis, Paracalanus indicus, Pseudodiaptomus inopinus, Tortanus forcipatus, and a hydromedusa, and barnacle nauplius, polychaeta larva, and a chaetognath Sagitta sp.) at salinities of 0, 5, 10, 15, 20, 25, 30, 35, and 40 psu when the organisms were exposed for 1 and 24 h, respectively. Survival 1Hs of P. inopinus and barnacle nauplius were 100% between 5 and 35 psu, while they were 0% at salinities of 0 and 40 psu. Survival 1Hs of A. omorii and A. pacifica, P. indicus, T. forcipatus, and polychaeta larva were 100% at $salinities\;\geq\;10$ psu, while they were 0% at lower salinities. Survival 1Hs of a hydromedusa and Sagitta sp. were 100% at $salinities\;\geq\;15$ psu, while they were 0% at lower salinities. Survival 1H of C. abdominalis and C. sinicus was 100% at $salinities\;\geq\;20$ psu, while they were 0% at lower salinities. Survival 24Hs of A. omorii, A. pacifica, C. abdominalis, barnacle nauplius, and polychaeta larva were the same as Survival 1 Hs at the same salinity, while those of the other metazooplankton were lower than Survival 1Hs. The results of the present study suggest that low salinity water emerging from big gates may cause the death of the metazooplankton, but the salinities at which death of the metazooplankton occurs may differ by species.

• 환경생물
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• 제32권4호
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• pp.306-310
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• 2014

본 연구에서는 톳 양식에서 pH 및 염분농도의 조절에 의한, 환경친화적인 해적생물 구제 방법을 개발하고자 하였다. 이를 위하여 톳의 내성범위를 구하고, 친환경적인 해적생물 구제법을 확립하고자 하였다. 톳에는 생리적 영향을 미치지 않는 친환경적인 해적동물 구제법으로서, pH 4 이하 조건과 pH 10 이상의 조건, 염분농도 10 psu 이하의 조건 및 44 psu 조건에서 효과가 있는 것으로 나타났다.