• 센서학회지
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• 제15권1호
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• pp.7-12
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• 2006

The multi-functional one-chip sensor has been fabricated to reduce output variation under various water environment. There were a temperature sensor, a piezoresistive type pressure sensor, and a electrode type conductivity sensor in the fabricated one-chip sensor. This sensor was measured water depth in the range of $0{\sim}180cm$, temperature in the range of $0{\sim}50^{\circ}C$, and salinity in the range of 0 $0wt%{\sim}5wt%$, respectively. Since the change of water depth in solution environment depends on various factors such as salinity, latitude, temperature, and atmospheric pressure, the water depth sensor is needed to be compensated. We tried to compensate the salinity and temperature dependence for the pressure in water by using lookup-table method.

• 수산해양기술연구
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• 제37권2호
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• pp.71-77
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• 2001

여수 연안 승망 어장의 주변 해역을 중심으로 조사한 해양 관측 자료와 현지에 조사한 어획량 등을 이용하여 여수 연안 승망 어장의 환경특성과 어획량 변동과의 관계를 분석 정리한 결과를 요약하면 다음과 같다. 1) 승망 어장에서의 수온의 분포범위는 13.0-$25.^0\circ$C이고, 4월부터 상승하기 시작하여 8월에 최고 수온 $25.^0\circ$C을 나타내다가 9월부터 하강하기 시작했다. 2) 어장에서의 염분의 분포범위는 28.6-33.8$\textperthousand$이고, 4월과 5월에는 32.0$\textperthousand$이상의 염분수가 분포하며, 6월부터 하강하기 시작하여 8월에는 최저염분 28.6$\textperthousand$를 나타내다가 9월부터 다시 상승하기 시작한다. 3) 여수 연안 승망에 어획되는 주어종인 숭어의 어획량은 5월에 최대 어획을 나타내고 6월부터 감소하기 시작하여 11월에는 최소 어획을 나타냈다. 수온이 높아지기 시작한 시기인 5월의 수온이 15.0-16$25.^0\circ$C에서, 저염보다 고염분인 32.6-33.8$\textperthousand$에서 어획이 양호하게 이루어졌다.

• 환경생물
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• 제36권2호
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• pp.232-240
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• 2018

본 연구는 거친대추멍게(Ascidiella aspersa)의 알 발육과 유생 부착에 미치는 수온과 염도의 영향을 파악하고자 실시하였다. 거친대추멍게 알 발육과 유생 부착 실험은 12개의 수온 조건(6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, $28^{\circ}C$,과 2개의 염도 조건(30, 34 psu)에서 진행하였다. 거친대추멍게 알의 부화율과 발육률은 염도에 관계없이 수온이 높아짐에 따라 증가하는 경향을 보였으며 최적 수온 범위 이후 감소하는 경향을 보였으며 부화 및 발육을 위한 최적 수온은 $20{\sim}22^{\circ}C$의 범위를 보였다. 저온 발육임계수온은 30 psu와 34 psu에서 각각 $1.5^{\circ}C$와 $1.8^{\circ}C$로 큰 차이를 보이지 않았다. 부착률은 염도에 관계없이 $16{\sim}22^{\circ}C$의 최적 수온 범위를 보였으며 부착시간은 수온이 증가함에 따라 지속적으로 증가하였다. 결과적으로 거친대추멍게의 최적 발육 및 생존 수온은 염도 조건에 관계없이 $20{\sim}22^{\circ}C$ 범위를 보였다. 본 연구결과는 국내 양식장에서의 거친대추멍게에 의한 경제적 피해가 증가하고 있는 시점에서 거친대추멍게의 분포 및 발생시기를 예측하고 확산 방지 및 방제 방안을 구축하는 데 활용될 수 있을 것으로 생각된다.

• Fisheries and Aquatic Sciences
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• 제8권3호
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• pp.161-166
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• 2005

We examined the variation in survival and the respiration and filtration rates of Tresus keenae in response to changes in water temperature and salinity. The survivorship of animals exposed to temperatures below $25^{\circ}C$ for 7 days was $80\%$; however, all test animals died on the fourth day at $28^{\circ}C$. The upper lethal temperature over 7 days was $25.9^{\circ}C$. After exposure to lower temperatures, $93\%$ ofthe animals survived at temperatures over $5^{\circ}C$ for 10 days. Survivorship rapidly decreased below $4^{\circ}C$ with all test animals dying at $2^{\circ}C$ on the eighth day. The $LT_{50}$ over 10 days was $4.8^{\circ}C$. The respiration and filtration rates of T. keenae increased as temperature increased. It is believed that energy consumption increases as a result of the increased respiration rate at temperatures above the upper lethal temperature. At temperatures below the lower lethal temperature, the metabolic rate of T. keenae was substantially lowered. In response to changes in salinity, the survivorship of T. keenae was $90\%$ at 30.2 psu after exposure for 5 days; at below 26.8 psu, all test animals died by the fifth day. The $LS_{50}$ was 29.1 psu. As salinity decreased, both the respiration rate and the filtration rate decreased. At 23.5 psu, the respiration and filtration rates decreased by 48 and $34\%$, respectively. These data have implications for increasing efficiency in the production and management of shellfish aquaculture farms.

• Journal of the korean society of oceanography
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• 제35권4호
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• pp.170-178
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• 2000

Low salinity water was observed during May in the Cheju Strait. Its structure and source were studied by using both the hydrographic data collected not only in the Cheju Strait during 1987-1989 but also in the wider area around Cheju Island extending to the Bank of Changjiang river in 1994 and the current data taken in the Strait during 1987-1989. The water had lower values of temperature, salinity, and density compared with the surrounding water and it was found in the surface layer outside of Tsushima Current Water 10-50 km off Cheju coast. The density of low salinity water was more dependent on salinity than on temperature. The low salinity water flowed into the Strait from the west as a series of intermittent waters whose size was variable in width and in thickness. The low salinity water was originated from the Chanajiang River Diluted Water. In the Cheju Strait, the water showed changes within 3 days on time and 30-50 km on space, and its sudden appearance was marked especially in May. Such strong variability and sudden appearance may be attributed to the beginning stage in May when the fresh water of Changjiang River Diluted Water starts to arrive in the Cheju Strait.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2007년도 춘계학술발표회
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• pp.43-50
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• 2007

In order to calculate the strength and to. see the variation af the stratification in the Southern Waters af Korea, the stratification parameter defined as potential energy anomaly (PEA, $V(J/m^3)$) introduced by Simpson and Hunter (1974) was used The data used in this paper were observed in August 1999 and February 2000 by National Fisheries Research and Development Institute (NFRDI). Also to know the effects af the temperature and the salinity an the stratification respectively, averaged temperature and salinity were used in the process af calculation the parameter. V is generally high in the offshore. However, in February, V in the onshore is higher than that of the offshore due to the vertical temperature gradient caused by the expansion of South Korean Coastal Waters (SKCW). In the summer, the increase af the atmospheric heating, the temperature inversion phenomenon act an the stratification as the buoyancy forcing. In most cases, the effects of the temperature on the stratification is stronger than that of the salinity. The temperature effect is predominantly due to the extent af the intrusion of Tsushima Warm Current into the study area. However, at stations where V is high the effect af the salinity is also significant. In the winter, V is very low due to the decrease of the buoyancy forcing, but same stations show the relatively high V due to the expansion of SKCW and Tsushima Warm Current.

• Ocean and Polar Research
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• 제33권spc3호
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• pp.371-383
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• 2011

To investigate the physical characteristics and variations of oceanic parameters in the tropical central North Pacific, oceanographic surveys were carried out in summer of 2006 and 2007. The survey periods were classified by Oceanic Ni$\tilde{n}$o Index as a weak El Ni$\tilde{n}$o in 2006 and a medium La Ni$\tilde{n}$a in 2007. The survey instruments were used to acquire data on CTD (Conductivity Temperature and Depth), XBT (Expendable Bathythermograph), and TSG (Thermosalinograph). The dominant temporal variation of surface temperature was diurnal. The diurnal variation in 2007, when the La Ni$\tilde{n}$a weather pattern was in place, was stronger than that in 2006. Surface salinity in 2006 was affected by a northwestward branch of North Equatorial Current, which implies that the El Ni$\tilde{n}$o affects surface properties in the North Equatorial Current region. Two salinity minimum layers existed at stations east of Chuuk in both year's observations. The climatological vertical salinity section along $180^{\circ}E$ shows that the two salinity minimum layers exist in $2^{\circ}N{\sim}12^{\circ}N$ region, consistent with our observations. Analysis of isopycnal lines over the salinity section implies that the upper salinity minimum layer is from intrusion of the upper part of North Pacific Intermediate Water into the lower part of South Pacific Subtropical Surface Water and the lower salinity minimum layer is from Antarctic Intermediate Water.

• 한국환경과학회지
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• 제18권2호
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• pp.141-151
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• 2009

Temperature, salinity, COD, DIN (Dissolved Inorganic Nitrogen), DIP (Dissolved Inorganic Phosphorus), and Chlorophyll ${\alpha}$ obtained from the southern coastal waters during the period of 2003 to 2005 were analyzed. Variability in temperature was not found between groups in southern coastal waters, but significantly different depending on sampling sites (p<0.05). The average temperature in 2003 estimated at $18.33^{\circ}C$ that was annually increased by 2005 and significantly different based on statistics (p<0.05). Unlikely to temperature, salinity was significantly different depending on sampling sites, as well as monthly variations (p<0.05). Likewise to temperature, the value of salinity was annually increased. COD estimated at the average of $>1.7\;mg\;l^{-1}$ for three years, indicating optimal water quality. The fluctuations of nutrients were extremely shown in different sampling sites and monthly variations. Chlorophyll a recorded above $2.0{\mu}g\;l^{-1}$ which was associated with high primary phytoplankton, whereas it showed much fluctuations in temporal and spatial, In particular, Tongyong, Jaranman, Jinjuman, and Samcheonpo located in the southeast were the highest fluctuations in water quality than any other regions. The correlation between salinity/COD and nutrients/chlorophyll a was strongly negative or positive, which was possibly associated with much the introduction of run-off water as well as rainfall in summer.

• 생태와환경
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• 제39권3호통권117호
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• pp.352-365
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• 2006

본 연구는 간척호 조성 초기 단계에 있는 화옹호를 대상으로 수환경의 변화를 파악하고자 2002년 6월부터 2006년 1월까지 수행하였다. 화옹호는 해양환경을 담수화시키는 과정에 있으므로 다양한 환경요인 중에서 강수량, 수온 및 염분도의 월 변동을 중심으로 하였다. 수온의 범위와 평균값은 각각 $-0.7{\sim}33.4^{\circ}C$, $13.6^{\circ}C$이었다. 상류부의 수온은 봄철${\sim}$여름철과 여름철${\sim}$가을철로 전이될때 빠르게 증가 또는 감소하였으나 하천 유입량이 많은 시기에는 일시적으로 다소 급감하는 현상을 보이기도 하였다. 반면에, 겨울철에는 상류부 저층의 경우 표층이나 하류부보다 수온이 다소 높은 양상을 보이기도 하였다. 염분의 범위와 평균값은 각각 0.3${\sim}$32.3 psu, 25.3 psu이었다. 염분은 수층에 따른 상하 수직적 차이가 현저하여 중층과 저층보다 표층에서 증감 변동이 매우 심하였다. 남양천이 유입되는 상류부의 저층을 제외하고는 전 정점에서 현격한 차이를 보이지 않았다. 이것은 저수지내 염분의 수직적 구배가 뚜렷하게 유지되고 있음을 의미하였다. 염분은 여름철 강우기에 해당하는 6${\sim}$10월에 변동폭이 매우 컸고, 표층의 경우 저염수가 상류에서 하류로 확장되는 현상이 뚜렷하였다. 이 시기에 표층의 수색은 황토색으로서 하천으로부터 유입 후 공급 이동된 저염수의 탁수층(turbidity plume)으로 뒤덮는 양상이 전개되었다. 저수지내 수온의 상 ${\cdot}$ 하 차이에 대한 범위는 $-10.6{\sim}9.7^{\circ}C$이었다 또한, 표층과 저층의 염분 차이는 $-27.1{\sim}30.0$ psu 범위이었다. 염분 농도의 차이가 큰 경우는 담수의 유입량이 크거나 배수갑문의 조작에 의한 해수유입이 많은 상태에서 나타났다. 수온과 염분의 관계는 음의 상관성을 보여, 즉 수온이 높을수록 염분 농도가 낮은 특성을 보였다.

• Fisheries and Aquatic Sciences
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• 제3권3_4호
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• pp.222-227
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• 2000

Fabrea salina living at salt pond is an interesting ciliate in the research of photobiology and live food for aquaculture. This study was carried out to understand the natural habitat of F. salina at salt pond, which would be a basic biological knowledge for the indoor mass culture of this ciliate. In this research, the water quality as temperature, salinity, dissolved oxygen, and chlorophyll-a was examined with the population density of the ciliate at salt pond. The highest population density of F. salina occurred at 109 ppt and $31^{\circ}C$with 2,390 inds./L in August, and the distribution of the ciliate was positively correlated with salinity, temperature, and chlorophyll­a. Even though F. salina is a very euryharine ciliate, it did not occur at the salinity below 47 ppt in this study. Its reason is able to be explained with the occurrence of many predators as small fish and food competitors as zooplankton living at low salinity of salt pont. While F. salina occurred with Anemia at the same habitat using the same food source, the optimum salinity for the ciliate was a little higher than that of Anemia, and the optimum temperature for the former was a little lower than that of the later. This should be a reason for that these two species have different ecological nich at the same habitat using the same food source.