• Ocean Science Journal
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• 제41권1호
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• pp.31-41
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• 2006

Seasonal changes of abundance of the main phytoplankton groups of species (diatoms, dinoflagellates, chrysophytes, small flagellates and cryptophytes) and a set of environmental parameters were investigated in coastal and pre-estuarine waters of Peter the Great Bay (East/Japan Sea) in May-October of 1998 and 1999. Three periods of mass development were revealed: spring, summer and autumn blooms, with successive change of species. The conditions favourable for each group of species were determined. Driving mechanisms of the succession include nutrients transport through seasonal pycnocline by turbulent mixing, terrestrial nutrients supply by monsoon floods, nutrients supply by upwellings, and light control by the thickness of upper mixed layer. Summer succession could be explained by a simple SST-MLD diagram similar to Pingree S-kh diagram with sea surface temperature as indicator of stratification (S) and mixed layer depth as indicator of light availability (kh).

• 한국동물학회지
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• 제13권3호
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• pp.94-100
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• 1970

C. challengeri는 아한대수의 전형적인 부유성 단각류로써 서부 북태평양의 $40^\\circ N$ 이북인 오야시오 수역에 널리 분포하고 있으며, 이 해역의 중심층 동물플랭크톤 생물량의 큰 비중을 차지하고있다. 본종은 구로시오 본류 이남이나 북태평양 중앙 수역에 가끔 출형하여 그 분포의 남한이 재검토 되었다. 한편 본종의 수직분포와 생물량의 일주수직이동도 아울러 검토되어 35-1,750m 사이에 서시하고, 주간에는 180-280m, 야간에는 35-100m에서 성군을 함을 알았다. 또 250m의 범위를 수직이동하여 상부의 유기물질을 심부로 수송하는 역할을 맡고 있다. 본종의 남하는 아한대중층수의 이동에 따르며 분포의 환경요인은 수온 $(10^\\circ C 이하)$과 염분도 (30 \ulcorner 이하)임을 밝혔다.

• ALGAE
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• 제21권4호
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• pp.425-432
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• 2006

Two species of Apoglossum is newly recorded in Korea collected from subtidal habitats of Jeju Island. Apoglossum minimum Yamada has previously been known only from the coast of Japan. It is characterized by having corticated midrib but lacking microscopic veins. Apoglossum gregarium (Dawson) Wynne is reported for the first time from the north western coast of Pacific Ocean. It has been distinguished by its ecorticate midrib from the former species. Their morphological characteristics in detail and taxonomic issues are discussed.

• Journal of Plant Biology
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• 제26권3호
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• pp.141-150
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• 1983

Antithamnion sparsum Tokida isolated from the southern and western coasts of Korea was investigated in culture, comparing the morphological character with A. defectum Kylin from the Pacific North America. A. sparsum basically showed a Polysiphonia-type life history. However, it sometimes exhibited a monoecious reproducton and the carpospores released from the cystocarp by self-fertilization unexpectedly developed into the plants bearing spermatangia alone. These male plants were not functional up to 60 days culture. The results of intraspecific crosses between populations of A. sparsum were positive and the hybrid carpospores gave rise to normal tetrasporophytes. On the other hand, theinterspecific crosses between A. sparsum and A. defectum were successful partly, evidenced by the gonimoblast development and the release of carpospores in case of A. sparsum (male)$\times$A. defectum (female), but not in case of A. sparsum (female)$\times$A. defectum (male). Thus, the both species were still under the speciation.

• 한국수산과학회지
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• 제48권6호
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• pp.940-946
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• 2015

The Indo-Pacific bottlenose dolphin Tursiops aduncus commonly inhabits the coastal waters of Jeju Island, Korea. An investigation was conducted using data from vessel sightings and point sightings from land. During 40 days of vessel sighting surveys between 2007 and 2010, a total of 18 dolphin groups were encountered. The overall sighting rate was 0.01 group/n.m. Most Indo-Pacific bottlenose dolphins were sighted within 500 m of the northern coast of Jeju Island during surveys. Also, dolphin groups were observed 47 times during 109 days of shore-based surveys conducted between 2011 and 2015. The results of a dolphin distribution survey conducted in 2011 were generally similar to the results of previous surveys. However, there were no dolphin sightings from 2012 in Hanllim-eup, in the north-western part of the island, where dolphins were sighted frequently until 2011, whereas dolphin observations increased in the southern part of the island. The mean group size was 35.4 (SD=18.08) individuals. The most frequently sighted group size was 36-40 individuals. To conserve resident dolphins off Jeju Island, long term sighting surveys and environmental assessment are required to monitor their distribution patterns.

• 한국농림기상학회지
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• 제9권4호
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• pp.217-227
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• 2007

서부양벚과실파리(Rhagolettis indifferens Curran)은 미국 북서부지역 및 California 북부에서 재배되는 단체리(Prunus avium)에 가장 큰 피해를 주는 해충이다. 체리의 수출을 위한 식물검역에서 Zero Tolerance의 규제를 받고 있는 이 해충의 방제를 위해 농가에서는 월동 후 우화 시점부터 지속적으로 약제를 살포하고 있으며, 살충제 처리의 적기를 예측할 수 있는 모형이 절실히 필요한 실정이다. 본 연구는 서부양벚과실파리를 대상으로 월동 후 성충의 우화 및 발생시기, 유충의 밀도변화, 번데기의 용화시기 및 밀도변화 등을 정량적으로 추적하여 개체군 밀도의 경시적 변동과 월동 후 우화시기를 예측하는 모형 검정의 기초자료로 사용코자 수행하였다. 이를 위하여 황색끈끈이트랩, 우화케이지, 용화트랩 등을 이용하여 실제 과원에서 각 태별 발생경과를 경시적으로 조사하였으며, 체리 과실이 달리는 시기부터 일정 간격으로 과실을 수거하여 시기별 과실 내부의 유충 수를 조사하였고, 실내에서 용화케이지를 이용하여 용화시기를 조사하였다. 그 결과 월동 성충의 우화는 5월 중순에 시작하여 6월 초순에 정점에 도달하였고, 6월 중순부터 7월 상순까지 과실 당 1마리 이상의 유충이 존재하였다. 7월 중순에 번데기의 수가 정점에 도달하였으며, 월동 중에 토양습도 등의 조건에 따른 번데기의 발육속도 및 생존율을 측정하기 위해 대량의 번데기를 확보하였다. 이 연구에서 얻어진 자료에서 나타난 과실파리의 월동 후 개체군 밀도변동과 용화시기를 Song et al.(2003)의 모형에서 예측한 결과와 비교한 결과 모형에 의해 예측된 발생일과 실측 발생일과는 1$\sim$2일 차이로 매우 정확하게 예측이 되었다. 이로 미루어 볼 때 본 연구에서 획득한 포장 실측자료는 누적 우화일, 유충의 발육단계, 산란일 등 다른 중요한 생물학적 사건을 예측하는 모형의 정확도 검정에도 잘 활용될 수 있을 것으로 생각된다.

• 한국해양환경ㆍ에너지학회지
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• 제6권1호
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• pp.30-43
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• 2003

반폐쇄성인 북서태평양 해역은 지형, 해류순환, 생태학적 관점에서 하나의 큰 시스템으로 간주되어 관리되어야 한다 현재 북서태평양권에서 진행되고 있는 해양환경 관련 다자간 협력 활동은 WESTPAC, PEMSEA, PICES, NOWPAP 등 다양하다. 본 논문에서는 특히 유엔환경계획의 주관하에 한ㆍ중ㆍ일ㆍ러가 지난 1994년부터 채택하여 수행중인 북서태평양보전실천계획(NOWPAP)사업을 중심으로 하여 북서태평양에서 진행되고 있는 지역협력 활동의 제반현황과 문제점을 살펴보고 이의 가능한 해결책을 제시하고자 하였다. 주요 제안으로는 (1) 북서태평양 인접국들은 해양환경 관련 국제협력 활동에 있어서 법적 구속력 있는 지역 차원의 협약의 중요성을 인식하고 실질적인 지역 협력활동을 수행함에 있어 큰 우산으로 작용할 수 있는 해양환경 관련 협약을 개발하여야 하며, 이에 (2) 현재의 제반 상황을 고려하여 현 단계에서는 국가의 영해나 관할권 등의 이슈를 침해하지 않는 느슨한 형태의 협약 개발을 시도할 필요가 있다. 아울러 (3) 지역내 다양한 정치 사회적 문제로 인해 환경분야의 협력사업이 종종 중단되거나 간섭받지 않도록 하기 위하여 유엔환경계획이나 다른 국제기구로부터의 지도력이 계속 발휘되어야 한다 (4) 재정적 및 제도적 기반을 계속 강화시켜야 하며, (5) 또한 북서태평양에서 연안 및 해양환경에의 위해 요소에 대응하기 위한 지역내 다자간 협력활동을 지속적으로 수행하여야 한다

• 한국환경과학회지
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• 제11권7호
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• pp.627-636
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• 2002

While typhoons were passing by the coastal and offshore waters around the Korean peninsula, the variations of the sea surface temperature (SST) were studied. To study on the variation, the data related to the 22 typhoons among 346 typhoons which occurred in the western Pacific during 1990∼1999, daily measured field SSTs at coastal and offshore, and imageries from advanced very high resolution radiometer on NOAA satellite during 1990∼1999 were used. The average variations of the SSTs were -0.9℃ at coastal waters and -2℃ at offshore around the Korean peninsula while the typhoons were passing by. In very near coastal waters from the land, the SST was not changed because the bottom depth of the coastal waters was shallower than the depth of thermalcline, while the typhoon was passing. The temporal and spatial variation of SSTs at coastal waters in summer were depended on the various types of the typhoons＇paths which were passing through the Korean peninsula. When a typhoon passed by the western parts including the Yellow Sea of the Korean peninsula upwelling cold water occurred along the eastern coastal waters of the peninsula. The reason was estimated with the typhoon that was as very strong wind which blew from south toward north direction along the eastern shore of the peninsula, led to the Ekman transport from near the eastern coastal area toward the offshore. While cold water was occurring in the eastern coast, a typhoon passed over the coastal area, the cold water disappeared. The reason was estimated that the cold water was mixed up with the surrounding warm water by the effect of the typhoon. While a cold water was occurring in the eastern coast, a typhoon passed by the offshore of the eastern coast, there were the increasing of the SST as well as the disappearing of the cold water. While a typhoon was passing by the offshore of the eastern coast, the cold water which resulted from the strong tidal current in the western coast of the peninsula was horizontally spread from the onshore to the offshore. We think that the typhoon played the role of the very strong wind which was blowing from north toward south. Therefore, the Ekman transport occurred from the onshore toward the offshore of the western coast in the Korean peninsula.

• 수산해양기술연구
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• 제35권3호
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• pp.227-236
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• 1999

Temperal and spacial analysis for catches have been drawing up a catch distribution chart and analysing catches and CPUE(Catch Per Unit Effort) using catch data with purpose of obtaining basic data to establish a selective method of effective fishing the tuna purse seine fishing ground.The temperature profile section and catch was surveyed to analyse the effect of catch in relation to the fishing ground environment.The results are as follows ;1. As for the catch variation between 1983 and 1984, the catch mainly took place on150^{\circ}E$, and after that it moved eastward enlarging the range of catch. In the monthly catch variation between January and February, the catches mainly happened on 135$^{\circ}$~ 150$^{\circ}$E, and then moved to the gradually westward. However, from July it moved to the South and from October Southeast.2. As to the eatch ratio for the school associated with the drifted object, the pelagic migrating school and the school associated with the biological objects, the catch ratio for the school associated with the drift objects was the highest. The catch ratio for the school associated with the drifted object was high in June, July and November whiles between January and March for the pelagic migrating school.3. SST(Sea Surface Temperature) was around 28~29^C$ on the observing line of 137^{\circ}E$ and the catches took place in the north equatorial counter-current situated on around $5^{\circ}~6^{\circ}N$. SST in the northern summer was 1^C$higher than winter and it was about 29~30^C$. The catch happened with the center of north equatorial counter-current. The reason why the catch mainly took place on the north equatorial counter-current is that main catch of tuna purse seine was the school associated with drift objects. It is thought that the fishing grounds are made in waters that have many drift objects like drift logs from the coast.

• 대기
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• 제24권3호
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• pp.283-301
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• 2014

In 2010, only 14 tropical cyclones (TCs) were generated over the western North Pacific (WNP), which was the smallest since 1951. This study summarizes characteristics of TCs generated in 2010 over the WNP and investigates the causes of the record-breaking TC genesis. A long-term variation of TC activity in the WNP and verification of official track forecast in 2010 are also examined. Monthly tropical sea surface temperature (SST) anomaly data reveal that El Ni$\tilde{n}$o/Southern Oscillation (ENSO) event in 2010 was shifted from El Ni$\tilde{n}$o to La Ni$\tilde{n}$a in June and the La Ni$\tilde{n}$a event was strong and continued to the end of the year. We found that these tropical environments leaded to unfavorable conditions for TC formation at main TC development area prior to May and at tropics east of $140^{\circ}E$ during summer mostly due to low SST, weak convection, and strong vertical wind shear in those areas. The similar ENSO event (in shifting time and La Ni$\tilde{n}$a intensity) also occurred in 1998, which was the second smallest TC genesis year (16 TCs) since 1951. The common point of the two years suggests that the ENSO episode shifting from El Ni$\tilde{n}$o to strong La Ni$\tilde{n}$a in summer leads to extremely low TC genesis during La Ni$\tilde{n}$a although more samples are needed for confidence. In 2010, three TCs, DIANMU (1004), KOMPASU (1007) and MALOU (1009), influenced the Korean Peninsula (KP) in spite of low total TC genesis. These TCs were all generated at high latitude above $20^{\circ}N$ and arrived over the KP in short time. Among them, KOMPASU (1007) brought the most serious damage to the KP due to strong wind. For 14 TCs in 2010, mean official track forecast error of the Korea Meteorological Administration (KMA) for 48 hours was 215 km, which was the highest among other foreign agencies although the errors are generally decreasing for last 10 years, suggesting that more efforts are needed to improve the forecast skill.