• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.2
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• pp.154-159
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• 2014

The increasing of atmospheric $CO_2$ are changing the pH (ocean acidification) and temperature of the sea. Although the effects of ocean acidification on calcifying organisms have well-documented, only a few studies have examined the combined effects of ocean acidification and elevated temperature. This study investigated the effects of ocean acidification and elevated temperature for 2100 on survival and growth of juvenile abalone, Haliotis discus hannai. Ocean acidification was simulated by bubbling $CO_2$ into seawater at concentrations of 1,000 and 1,500 ppm, and temperature was set at room temperature $+2^{\circ}C$. Neither $CO_2$ nor temperature had a significant effect on survival of abalone, while both significantly affected growth. There was no significant interaction between the two factors. Shell length can be used as a growth index of abalone to access the impacts of ocean acidification and elevated temperature.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.194-195
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• 2000

난바다곤쟁이는 북태평양 동부해역으로부터 베링해, 오우츠크해, 동해와 황해에 이르기까지 광범위하게 분포하는 종으로서 형태학적 분류관점에서 동일종으로 간주되고 있다. 최근에 밝혀진 황해 개체군의 생태학적 특성에 의하면 미국 서부해역과 황해에 서식하는 두 개체군은 지리적으로 멀리 떨어져 있음에도 불구하고 공히 비교적 낮은 수온 (< 1$0^{\circ}C$)의 수심에서 서식하며 강력한 일주수직상승운동 (diurnal vertical migration)을 수행하는 등 많은 특성을 공유하는 것으로 밝혀졌다 (Yoon et al., in press). 본 연구는 미국 서부연안과 한국 서해에 서식하는 난바다곤쟁이 개채군의 물리, 생태, 형태학적인 공통 특성이 유전학적인 측면에서도 관찰되는지를 조사하고자 한다. (중략)

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.11a
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• pp.321-321
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• 2015

해수 환경에 노출된 대부분의 금속재료는 직 간접적으로 부식의 영향을 받는다. 이와 같이 해수에 침지된 금속재료의 부식 방지에는 음극방식법이 주로 사용되고 있다. 과거의 음극방식 설계에는 양극 크기와 방식전류 밀도, 소모율 등 양극 자체에 대한 변수만이 고려되었으나, 20여 년 전부터는 해수 오염도, 수온 및 유속 등을 종합적으로 고려하여 설계하고 있다. 특히 대부분의 금속은 부식성 환경에서 생성된 부동태 피막이 해수 유동에 의해 파괴되면서 급속히 손상된다. 따라서 본 연구에서는 해수 특성을 고려한 최적의 소요방식전류밀도 선정을 위해 전기화학실험을 실시하였다. 실험 결과, 해수 온도 상승에 따라 확산속도가 빨라져 최적 방식 전류밀도가 증가하는 경향을 나타냈다.

• Korean Journal of Environmental Biology
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• v.27 no.3
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• pp.285-291
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• 2009

The effects of water temperature on oxygen consumption (OC) of starry flounder Platichthys stellatus reared in seawater (SW) and freshwater (FW) was performed in closed water-recirculating system containing respiratory chamber. Fish acclimated in separate indoor tanks with SW (nine of fish used, $263.0{\pm}40.4$ g) or FW (nine of fish used, $265.8{\pm}34.8$ g) were sampled. The OC of starry flounder at $15^{\circ}C,\;20^{\circ}C$ and $25^{\circ}C$ were $74.4{\pm}17.0,\;85.9{\pm}15.8,\;98.3{\pm}11.4\;mg\;O_2\;kg^{-1}hr^{-1}$ in SW and $46.7{\pm}12.0,\;63.3{\pm}7.5,\;82.6{\pm}5.3\;mg\;O_2\;kg^{-1}hr^{-1}$ in FW, respectively, showing a linear increase in OC with water temperature. The OC of fish reared in both SW and FW clear diel rhythm, with lower values at daytime and higher values in the night, in accordance with light (09:00~21:00 hr) and dark (21:00~09:00 hr) phases of the diel cycle (12L : 12D) in water temperature at $15^{\circ}C$ and $20^{\circ}C$. However OC of fish reared in both SW and FW showed unclear diel rhythm with light and dark phases of the diel cycle in water temperature at $25^{\circ}C$. Starry flounder reared in FW had higher ventilation rates than those in SW, but SW had higher OC per breath than those in FW.

• Journal of Aquaculture
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• v.19 no.3
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• pp.210-215
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• 2006

An experiment was conducted to investigate the effects of four water temperatures (10, 15, 20, and $25^{\circ}C$) in combination with three photoperiods (24L:0D, 12L: 12D, and OL:24D) on the oxygen consumption rate of juvenile dark-banded rockfish, Sebastes inermis (mean body weight $20.5{\pm}0.7g$). The oxygen consumption rates of S. inermis were measured in triplicate for 24 hours using a continuous flow-through respirometer. Different combinations of water temperatures and photoperiods resulted in significant differences in the mean oxygen consumption rate of S. inermis (P<0.001). The oxygen consumption increased with increasing water temperatures for all photoperiod treatments (P<0.01). Mean oxygen consumption rates at 10, 15,20 and $25^{\circ}C$ ranged $178.3\sim283.5,\;386.7\sim530.7,\;529.2\sim754.3$ and $590.0\sim785.5mg\;O_2kg^{-1}h^{-1}$, respectively. $Q_{10}$ values ranged $3.17\sim5.51$ between 10 and $15^{\circ}C,\;1.87\sim2.10$ between 15 and $20^{\circ}C$ and $1.08\siml.24$ between 20 and $25^{\circ}C$, respectively. Fish held in continuous darkness (OL:24D) used consistently less okygen than fish exposed to continuous light (P<0.05). The mean oxygen consumption offish in a 12L:12D photoperiod was higher than that offish in 24L:0D and 0L:24D photoperiods under all temperature treatments except $10^{\circ}C$. The oxygen consumption of fish exposed to the 12L:12D photoperiod was significantly higher during the light phase than during the dark phase under all temperature treatments except $10^{\circ}C\;(P<0.05)$. This study provides empirical data for estimating oxygen consumption of S. inermis under given condition. This result has application for culture management and bioenergetic model for growth of this species.

• Korean Journal of Ichthyology
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• v.20 no.4
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• pp.239-247
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• 2008

The objective of this investigation was to examine oxygen consumption (OC) and operculum movement number (OMN) of rainbow trout Oncorhynchus mykiss as a function of changes in water temperature (WT). The WT of the rearing facility was increased from $4^{\circ}C$ to $28^{\circ}C$ stepwise at $1^{\circ}C$ day at each WT (5, 10, 15, 17, 20, 23, 26, and $28^{\circ}C$) then OC and OMN were measured. The OC of the fish increased linearly with WT: O=25.0240 WT+17.5400 in the range of $4{\sim}23^{\circ}C$ However, at 26 and $28^{\circ}C$ the OC declined to around the level at $10^{\circ}C$. The OMN also increased linearly with temperature: OMN=4.4847 WT+59.2150 in the range of $4{\sim}23^{\circ}C$ but at 26 and $28^{\circ}C$ the OMN of the fish dropped slightly. The OC and OMN of the fish showed peak at $23^{\circ}C$ with the lowest values at $4^{\circ}C$. In the range of $4{\sim}23^{\circ}C$, the relationship between OC and OMN of the fish was expressed as a linear equation: OC=0.0923 OMN-308.2100. The OC of fish transferred from $15^{\circ}C$ to certain temperatures without acclimation showed a lower OC at 5 and $10^{\circ}C$ but above $15^{\circ}C$ the OC increased/decreased with temperature. The trout died in temperatures above $28^{\circ}C$ even when acclimated step by step with a $1^{\circ}C$ day increase in WT. In this experiment, a negative physiological changs occurred in the experimental fish at $23^{\circ}C$ suggesting that the optimal physiological temperature range of rainbow trout is $10{\sim}20^{\circ}C$.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.337-341
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• 2009

지구의 평균기온이 지속적으로 상승함에 따라 지구온난화로 인한 기후변화는 지구에 분포되어 있는 극지방의 빙하들을 녹임으로써 지구의 물 순환시스템을 교란시켜 집중호우와 태풍, 가뭄, 낙뢰 등 예측을 불허하는 극한 기상변화를 발생시키고 있다. 기후변화로 인해 바다의 수온이 상승함에 따라 빙하가 녹거나 바닷물이 팽창하여 해수면이 상승하게 되는 바, 1990년 대비 2000년대에 동해바다에서는 상승률이 0.07cm/yr이던것이 0.20cm/yr로 나타났으며, 서해바다에서는 0.14cm/yr이던 것이 0.18cm/yr로 나타났고, 남해바다에서는 0.32cm/yr이던 것이 0.34cm/yr 로 평균상승률이 1990년대에 비해 증가하는 것으로 관측되었다. 본 연구에서는 기후변화로 인한 자연재해 피해를 최소화하기 위해 소방방재청의 현행 업무를 중심으로 재해를 예방하기 위한 풍수해 업무별 추진해야할 연구과제들을 조사 제시하고자 하였다. 기후변화에 따른 재난분야의 정책과 관련된 연구적인 측면의 분야를 제시하기 위하여 최근에 나타난 자연재난 피해현상에 대한 원인 및 대책을 기초로 하여, 재난관리분야에서 추진하고 있는 업무를 계승 발전시킴으로써 기후변화로 인한 피해를 예방 또는 최소화 할 수 있는 방향으로 제시하고자 하였다. 기후변화에 따른 소방방재청의 풍수해 재난관리 분야 종합계획을 제시하기 위해 본 연구에서는 기후변화 관련 최근 국내 외의 동향을 먼저 살펴보았다. 1977년부터 2006년까지 우리나라 최근 30년간의 재해연보에 제시되어 있는 시설물별 피해액을 조사하여 시설물 중 피해액이 많은 순으로 주요피해 시설물을 파악하였다. 여기에서 주요피해 시설물로는 하천, 도로, 소하천, 수리, 농경지, 사방 등의 순으로 나타났다. 이러한 주요시설물에 대한 피해현황을 파악하기 위하여 대규모 풍수해 피해에 대한 현황, 원인분석 및 대책이 제시되어 있는 각종 피해조사 보고서, 연구보고서 및 전문 학술지 기사들을 수집 분석하였으며, 수집된 자료를 토대로 각각의 재해피해현상에 대하여 시설물의 피해현상, 원인 및 대책을 분류하여 분석하고자 한다. 재난관리 분야 중 우수유출저감시설 관련 제시된 업무방향을 보면 침투 저류를 위한 우수유출저감시설의 개발연구, 침수위험지구의 지정기준 등급별 방재대책 방안연구, 유역별 재해위험 저감능력의 평가기준 개발, 단위구역별 우수유출저감시설의 확보기준 연구, 우수유출저감시설의 국내 표준화 방안 연구, 우수유출저감시설 설치자에 대한 인센티브 도입방안 연구, 피해지역의 매입을 통한 저류지화 방안 연구, 우수유출저감시설 설치효과의 교육 홍보 및 우수유출저감시설의 국제 표준화 기준 제정 추진 등이 필요할 것으로 조사되었다. 여기에서 제시된 재난관리 업무분야별 많은 연구과제들이 향후 연구할 수 있는 재원확보로 이어져 재난관리의 업무발전에 도움이 될 수 있도록 하여야 하겠으며, 주요 결론으로는 다음과 같다. 첫째, 우리나라는 기후변화에 대해서는 기존에 소극적으로 대응하였으나 기후변화대책기획단을 만들어 적극적으로 대처하고 있으므로 기후변화와 관련된 여러분야가 활성화 될 것으로 판단된다. 둘째, 국외의 기후변화 대응사례에서 보면 시설물의 규모를 볼 때 큰 규모의 예산을 투입하는 것으로 판단되는바, 이는 향후의 불확실한 기후변화에 대비하는 선진적인 판단으로 검토되어야 할 것이다. 셋째, 풍수해 관련 주요업무 8가지에 대하여 추진해야할 업무방향 48개를 선정 제시하였다.

• Development and Reproduction
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• v.4 no.2
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• pp.175-180
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• 2000

The reproductive cycle of ovoviviparous melania snail, Semisulcospira libeytina libertina was studied in the valley near Naewon Temple in Yangsan, Korea. Water temperature (WT) of the habitat ranged from 1.3$^{\circ}C$ to 22.5$^{\circ}C$ The meat weight rate (MWR) reached the maximum with the beginning of WT increase in March and the minimum in August. Monthly changes in average oocyte diameter showed the maximum (249.6$\pm$2.6 ${\mu}{\textrm}{m}$) in July and the minimum (134.3$\pm$2.8 ${\mu}{\textrm}{m}$) in December S. libertina libertina seemed to be a year-round breeder except for mid-summer and mid-winter. Two main reproductive cycle of the species could be divided into five successive stages: multiplicative (March, October), growing (April and May, November), mature (June and July, December), ovulation (August, January), parturition (September and October, March to May) and resting (September, February) stages in female and multiplicative (March, October), growing (April, November), mature (March to June, December), copulatory (July and August, January), resting (September, February) stages in male.

• Journal of Korean Society on Water Environment
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• v.29 no.2
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• pp.232-238
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• 2013

Water temperature is key factor influencing growth and reproduction of fish and its increase give rise to various physiological changes including gene expression. Heat shock protein (Hsp), one of the molecular chaperones, is highly conserved throughout evolution and its expression is induced by various stressors such as temperature, oxidative, physical and chemical stresses. Here, we isolated partial cDNA clones encoding 70-kDa Hsp (Hsp70) and $\beta$-actin using reverse transcriptase-PCR (RT-PCR) from gut of Rhynchocypris kumgangensis, a Korean indigenous species and cold-water fish, and investigated expression profiles of Hsp70 under an increase of water temperature using $\beta$-actin as an internal control for RT-PCR. Cloned Hsp70 cDNA of R. kumgangensis showed homology to Ctenopharyngodon idella (96%), Hypophthalmichthys molitrix (96%), Danio rerio (93%) and Oncorhynchus mykiss (81%) Hsp70. Cloned $\beta$-actin cDNA of R. kumgangensis showed homology to D. rerio (98%), H. molitrix (97%), C. idella (97%) and O. mykiss (90%) $\beta$-actin. Both mRNA of Hsp70 and $\beta$-actin were expressed in gut, brain, and liver in R. kumgangensis. Futhermore, expression of Hsp70, in brain, was highly augmented by an increase of water temperature. These results suggest that Hsp70 mRNA expression level in brain can be used as a biological molecular marker to represent physiological stress against an increase of water temperature.

• Microbiology and Biotechnology Letters
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• v.31 no.3
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• pp.264-270
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• 2003

A quantitative survey of the protozoa microfauna at bioreactor of advanced sewage treatment plant was carried out during a period of 11 months. In this study, 32 genera were identified, including 17 ciliates. The abundance of the important protozoa were compared with the operating parameters and water quality of the effluent of the plant using statistical procedure. Statistical analysis revealed a relationship between the abundance of some genera and removal rate. In particular, correlation analysis on the quality of effluent and protozoa indicated that Lepadella may be used as the bioindicator of TP removal and Trochilia, Entosiphon, Colepus may be used as the bioindicator of TN removal when water temperature was below $20^{\circ}C$.