• Ocean and Polar Research
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• 제32권4호
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• pp.351-359
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• 2010

This study examined extensive patches of floating green macroalgal (Ulva prolifera) mats in the northern East China Sea (ECS) using satellite images from mid May through July 2008 and field observation made during early August 2008 cruise. It was previously reported that the massive macroalgal blooms occurred in the coastal areas of Qingdao in China. During our field survey, researchers noticed widely distributed floating patches of macroalgal mats ranging in size from tens of centimeters to a few hundred meters in diameter. Meteorological data in the northern ECS showed high irradiance, high air-temperature, and predominant southerly winds in summer. In the study area during the survey period, surface waters were characterized by the Changjiang Diluted Water (CDW) mass, which contained high concentrations of nitrate and phosphate. The internal transcribed spacer (ITS) sequence of U. prolifera found in the northern ECS was the same as those of U. prolifera sampled from Qingdao blooms, suggesting a possibility that U. prolifera found in two regions would be derived from the same origin. We suggest that U. prolifera in the nearshore Jiangsu Province drifted into the northern ECS and proliferated under favorable meteorological and oceanographic conditions during the summer of 2008.

• 한국환경과학회지
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• 제15권7호
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• pp.623-634
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• 2006

In this study, characteristics of fog at Mokpo as the west coastal area of Jeonnam were investigated, using statistical analysis of observed fog and meteorological data. Higher frequency of the fog occurrence at Mokpo was showed in spring(32%) and summer(34%) due to the seasonal high atmospheric pressure. Regional characteristics as radiation cooling, advection of fog and water vapor from surrounding sea and Yeongsan lake, and frontal fog had major effect on the coastal fog at Mokpo on the meteorological conditions of north-west/south wind and calm($0{\sim}2m/s$). Also, as the results of analyzing data of before and after the construction of Yeongsan dam, the frequency of annual mean fog days increased 41 %, specially increased 178% in autumn. The increase of fog days mainly resulted from evaporation during colder seasons and from temperature inversion during warmer seasons over the water surface of Yeongsan lake. The construction of Yeongsan dam had a little effect on the meteorological conditions concerning fog occurrence, because Yeongsan dam which only supplies the water for use do not always carry out outlet of the cold water. In addition, the sea fog at Heuksando located in offshore had not effect on the occurrence of fog at Mokpo.

• 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.

• Ocean and Polar Research
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• 제41권4호
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• pp.251-263
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• 2019

We investigated the mesozooplankton community structure during autumn in the southern Yellow Sea. Mesozooplankton density generally ranged from 352 to 2,954 ind. m^-3 and varied according to different sampling stations. The copepod Paracalanus parvus s.l. and its copepodites dominated in the communities, corresponding to 57.3% in density of the total. Surface and water-column averaged salinity were positively correlated with density of total mesozooplankton, copepods and a few dominant species, and the tunicate Thalia rhomboides was negatively related to chlorophyll-a concentration. The mesozooplankton community of the study area was divided into three groups according to the cluster analysis using species composition and density: one in the northern coastal region, another in the northern offshore region, and the other in the south. The most significant indicator species for each of the groups were Labidocera euchaeta in the northern coastal region, T. rhomboides in the northern offshore region, and Themisto sp. juveniles in the south. This study provides recent data on the characteristics of the mesozooplankton community in the southern Yellow Sea, which may be valuable for gaining a better understanding of changes in the pelagic ecosystem of the Yellow Sea.

• 해양환경안전학회지
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• 제15권4호
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• pp.345-354
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• 2009

해역이용협의에 따른 협의서 검토현황과 연안이용형태를 분석한 결과, 공유수면 점 사용은 공작물설치와 해수 취배수, 공유수면 매립은 산업단지조성, 항만 어항개발과 도로건설의 점유율이 높았고, 점 사용은 서해에서 그리고 매립은 남해에서 우세하였다. 지역별로는 전남, 경남지역과 인천 경기지역에서 이용행위가 많았다. 해역이용협의 검토량은 2008년이 전년도에 비해 약 200건 이상 증가하였고, 협의과정에서 준설토 해양투기, 매립, 준설, 해수 취배수, 바다골재채취와 규사채취에 대해 보완요청이 주로 이루어졌다. 연안이용은 대부분 해양환경기준 I등급 또는 II등급의 지역에서 집중되었고, 특히, 법령상 해양 규제지역인 특별관리해역에서는 항만 어항개발과 관련된 매립과 공작물설치, 국립공원에서는 공작물설치와 호안정비가 많았다. 또한, 수산자원보호구역에서는 호안정비, 공작물설치와 해수의 취배수 행위가 많이 이루어진 것으로 평가되었다. 해역이용협의제도의 제반적인 합리성과 신뢰성을 높이는 방법 등 개선방안을 제도운영 및 정책적인 측면과 협의서 작성과 관련한 해양환경영향평가 측면으로 구분해서 정책제언을 제시하였다.

• 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.

• Journal of Species Research
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• 제10권2호
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• pp.184-190
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• 2021

The diversity of scuticociliates (subclass Scuticociliatia Small, 1967) had previously been superficially investigated in Korea and only 10 species were reported according to the National Species List of Korea published in 2019. Here, we identify four scuticociliates, collected from three coastal water samples, by observing protargol-impregnated specimens. As a result, the present species belong to the order Pleuronematida Fauré-Fremiet in Corliss, 1956 and their lower taxonomic classifications are as follows: family Eurystomatellidae Miao et al., 2010 - Eurystomatella sinica Miao et al., 2010; family Pleuronematidae Kent, 1881 - Pleuronema grolierei Wang et al., 2008, P. setigerum Calkins, 1902, and Schizocalyptra aeschtae Long et al., 2007. The family Eurystomatellidae and the genus Schizocalyptra Dragesco, 1968 are reported for the first time in Korea. Considering that the scuticociliates are a species-rich group and very common in most habitats(including freshwater and terrestrial habitats), our findings indicate that we are far from understanding the complete diversity of Korean scuticociliates.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.696-700
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• 2004

In the Korean seas, Sea Surface Temperature (SST) and Thermal Fronts (TF) were analyzed temporally and spatially during 8 years from 1993 to 2000 using NOAA/AVHRR MCSST. As the result of harmonic analysis, distributions of the mean SST were $10~25^{\circ}C,$ and generally SST decreased as latitude increased. SST increased in the order as following; the South Sea $(20\~23^{\circ}C),$ the East Sea $(17\~19^{\circ}C)$, and the West $Sea(13\~16^{\circ}C).$ Annual amplitudes and phases were $4\~11^{\circ}C,\;210\~240^{\circ}$ and high values were shown as following; the West Sea $(A1,\;9\~11^{\circ}C),$ the Northern East Sea $(A5,\;8\~9^{\circ}C),$ the Southern East Sea $(A4,\;6\~8^{\circ}C),$ the South Sea $(A3,\;6\~7^{\circ}C),$ the East China Sea $(A2,\;4\~7^{\circ}C)$ and phases; $A3\;(238\~242^{\circ}),\;A4\;(235\~240^{\circ}),\;A5\;(225\~235^{\circ}),\;Al\;(220\~230^{\circ}),\;A2\;(210\~235^{\circ}),$ respectively, Both of them were related inversely except the area A2, therefore the rest areas were affected by seasonal variations. TF were detected by Soble Edge Detection Method using gradient of SST. Consequently, TF were divided into 4 fronts; the Subpolar Front (SPF) based on the Cold Water Mass (low SST and salinity Subartic Water), resulting from the North Korea Cold Current (NKCC) and the East Sea Proper Cold Water in the middle and low layer, and the Warm Water Mass (high SST and salinity Subtropical Water), resulting from the Tsushima Warm Current (TWC) in area A4 and 5, the Kuroshio Front (KF) based on the Kuroshio Current (KC) and shelf waters in the East China Sea (ESC) in A2, and the South Sea Coastal Front (SSCF) based on the South Sea Coastal Water (SSCW) and TWC in A3. Also, the Tidal Front was weakly appeared in AI. TF located in steep slope of submarine topography. Annual amplitudes and phases were bounded in the same place, and these results should be considered to influence of seasonal variations.

• 한국수산과학회지
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• 제57권4호
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• pp.380-388
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• 2024

This study investigated the sexual maturation of the marbled flounder Pseudopleuronectes yokohamae, a commercially important flatfish species, through monthly sampling from the coastal waters of Pohang in the East Sea of Korea in 2022. We analyzed monthly changes in total length (TL), gonadosomatic index, maturity stage, and 50%, 75%, and 97.5% group maturity based on visual assessments and histological analysis of the gonads. The spawning period was determined to be from December to May. The TL at 50% maturity was 26.4 cm for females and 24.8 cm for males. These findings provide a basis for developing resource management strategies for Pleuronectidae.

• 한국해양학회지:바다
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• 제8권2호
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• pp.151-163
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• 2003

본 논문은 섬진강 담수가 해양으로 유입하는 남해의 여수해협 -소리도 연안 해역에서 홍수기 (일평균 강우량 50 mm 이상이 10일간 지속)동안 형성된 염하구 환경의 물리-화학적 특성(공간분포 및 조절인자)에 관하여 조사 . 연구한 결과이다. 섬진강 담수는 해수와 비교하여 수온, 염분, pH가 낮고 COD와 영양염(특히 질산염 ) 농도가 높은 특성을 갖는다. 겨울철 갈수기와 달리 여름철 홍수기에는 이러한 특성의 담수가 섬진강 하구에서 약 20~60 km떨어진 전 연구해역으로 유입ㆍ확산되어 광범위한 염하구 환경을 형성하는 것으로 밝혀졌다. 본 연구에서는 여름철 홍수기 동안 일시적으로 형성되는 염하구를 일반적인 강 하구의 염하구(river estuary)와 구분하여 “연안 염하구(coastal pseudo-estuary)"로 정의 하고자 한다. 한편, DIN/DIP비는 겨울철 갈수기보다 여름철 홍수기에 훨씬 더 높으며, 이는 일반적으로 논에서 사용되는 질소 화학비료 때문인 것으로 해석된다. 이러한 연안 염하구 환경의 해수중에서 물리-화학적 인자들의 공간 분포와 거동 특성은 일차적으로 섬진강이 공급하는 담수와 해수의 물리적 혼합과 이 과정에서 일어나는 탈착 및 기타 생지화학적 요인 등에 의해 조절되는 것으로 해석된다. 본 연구에서 제시된 연안 염하구 환경 특성은 전반적으로 강 하구의 염하구 환경 특성과 크게 다르지 않은 것으로 판단된다.판단된다.