• 한국환경과학회지
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• 제21권2호
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• pp.125-133
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• 2012

Climatological trend for the period of 1970 to 2009 in sea water temperature around the Antarctic Peninsular waters in the Southern Ocean was investigated. During the period from 1970 to 2009, sea water temperature in the top 500 m water column except 100 m increased at a rate of $0.003-0.011^{\circ}C{\cdot}yr^{-1}$, but at 100 m it decreased at a rate of $-0.003^{\circ}C{\cdot}yr^{-1}$. Although long-term trend is generally warming, there were several periods of sharp changes between 1970 and 2009. Annual mean sea water temperature between surface and 500 m except 100 m decreased from the early of 1970s to the end of 1980s, and then it increased to the end of 2000s. In the entire water column between the surface and 500 m, sea water temperature closely correlated with the El Nino events expressed as the Southern Oscillation Index(SOI), and SOI and sea water temperature have a dominant period of about 3-5 years and decade.

• Ocean and Polar Research
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• 제27권2호
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• pp.231-235
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• 2005

The European Iron Fertilization Experiment EIFEX studied the growth and decline of a phytoplankton bloom stimulated by fertilising $10km^2$ in the core of a mesoscale $(80{\times}120km)$ cyclonic eddy south of the Antarctic Polar Front with about 2 times 7 tonnes of iron sulphate. The phytoplankton accumulation induced by iron fertilization did not exceed $3{\mu}g\;chl\;a\;l^{-1}$ despite a draw down of $5{\mu}M$ of nitrate that should have resulted in at least double to triple the amount of phytoplankton biomass assuming regular Redfield-ratios for draw down after phytoplankton growth in the Southern Ocean. During EIFEX the fertilized core of the mesoscale eddy evolved to a hotspot for a variety of small and medium sized mesozooplankton copepods. In contrast to copepods, the biomass of salps (Salpa thompson)) that dominated zooplankton biomass before the onset of our experiment decreased to nearly extinction. Most of the species of the rnosozooplankton community showed extremely hiか feeding rates compared to literature values from Southern Ocean summer communities. At the end of the experiment, massive phytoplankton sedimentation reached the sea floor at about 3800m water depth.

• 지구물리
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• 제3권3호
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• pp.141-152
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• 2000

남극반도 엘리펀트섬 북부의 남극-스코시아판 경계부에서 획득한 지구물리 자료(탄성파, 중력자료)는 셰클턴 파쇄대를 따라 지각구조의 급격한 변화를 보여준다. 이들 자료에 의하면 셰클턴 파쇄대의 해저산맥은 남극반도 대륙주변부 앞에서 중단되지만, 파쇄대의 변환단층대는 엘리펀트섬 부근의 주변부까지 계속 연장되며 그 넓이도 확장되고 있음을 보여준다. 즉 셰클턴 파쇄대의 변환단층은 남동쪽으로 내려오면서 (1) 드레이크 해협에서는 지구(graben) 구조의 함몰대, (2) 파쇄대 산맥의 남쪽 끝, 삼중점 바로 남동쪽에서는 해양지각에 대규모 반지구(half-graben) 구조, (3) 남극반도 엘리펀트섬 북쪽 대륙사면을 심하게 변형시키는 단층군으로 그 형태를 변화한다. 셰클턴 파쇄대의 단층대를 따라 두 단계의 판구조 환경 변화가 진행되었다. 첫 번째 단계는 대규모 정단층운동에 의해 반지구구조와 같은 확장구조를 형성시킨 확장력 환경이다. 이 시기는 드레이크 해협의 확장이 진행되었던 중기 마이오신세(약 $10Ma{\sim}20Ma$ 사이)에 해당된 것으로 추정된다. 두 번째 단계는 셰클턴 단층을 역단층운동으로 재활성화 시킨 최근의 압축력 환경으로, 이는 최근 약 6Ma이후 진행된 스코시아판의 서향운동으로 인한 남극판과의 수렴작용에 의한 것이다.

• 한국수산과학회지
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• 제21권5호
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• pp.292-296
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• 1988

This review has dealt with the topics of biology of Antarctic krill, Euphausia superba. There are much of work on various aspects of the biological pattern of krill, in particular on reproduction, feeding and longevity. Nevertheless, the details of winter biology of krill still remained to be unclear. It is suggested that three kinds of energy Pathways, from inorganic or organic materials to krill, may occur in the Antarctic Ocean.

• 한국수산과학회지
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• 제21권5호
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• pp.303-310
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• 1988

This review has dealt with the topics of biology of Antarctic krill, Euphausia superba. There are much of work on various aspects of the biological pattern of krill, in particular on reproduction, feeding and longevity. Nevertheless, the details of winter biology of krill still remained to be unclear. It is suggested that three kinds of energy Pathways, from inorganic or organic materials to krill, may occur in the Antarctic Ocean.

• Ocean and Polar Research
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• 제21권2호
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• pp.109-116
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• 1999

Total lipid content, lipid class and fatty acid composition of the Antarctic krill Euphausia superba collected from the water of King George Island, Antarctica during austral summer of 1997-1998, were investigated. The overall lipid content of 5. superba was 72 mg/g dry mass similar to the reported values for most temperate species. The neutral lipid of E. superba was 29% of the total lipid and that of phospholipid was 71%. The majority of neutral lipid was triacylglycerols(31.6% of neutral lipids) while phosphatidyl choline (44% of phospholipid) was the most abundunt in phospholipids. The quantitative composition of the fatty acid in E. superba show consisting mostly of the saturated 16:0 (16.6% -22.1%), along with the polyunsaturated 20:5(n-3) (20.6% -22.1%) and 22:6(n-3) (14.9% -16.9%) acids.

• Journal of Microbiology and Biotechnology
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• 제17권9호
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• pp.1483-1490
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• 2007

A Gram-negative, motile by tuft flagella, obligately aerobic chemoorganoheterotrophic, sphere-form bacterium, designated $IMCC3135^T$, was isolated from the Antarctic surface seawater of King George Island, West Antarctica. The strain was mesophilic, neutrophilic, and requiring NaCl for growth, but neither halophilic nor halotolerant. The 16S rRNA gene sequence analysis indicated that the strain was most closely related to genera of the order Chromatiales in the class Gammaproteobacteria. The most closely related genera showed less than 90% 16S rRNA gene sequence similarity and included Thioalkalispira (89.9%), Thioalkalivibrio (88.0%-89.5%), Ectothiorhodospira (87.9%-89.3%), Chromatium (88.3%-88.9%), and Lamprocystis (87.7%-88.9%), which represent three different families of the order Chromatiales. Phylogenetic analyses showed that this Antarctic strain represented a distinct phylogenetic lineage in the order Chromatiales and could not be assigned to any of the defined families in the order. Phenotypic characteristics, including primarily non-phototrophic, non-alkaliphilic, non-halophilic, and obligately aerobic chemoheterotrophic properties, differentiated the strain from other related genera. The very low sequence similarities (<90%) and distant relationships between the strain and members of the order suggested that the strain merited classification as a novel genus within a novel family in the order Chromatiales. On the basis of these taxonomic traits, a novel genus and species is proposed, Granulosicoccus antarcticus gen. nov., sp. nov., in a new family Granulosicoccaceae fam. nov. Strain $IMCC3135^T\;(=KCCM42676^T=NBRC\;102684^T)$ is the type strain of Granulosicoccus antarcticus.

• Ocean and Polar Research
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• 제23권4호
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• pp.411-417
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• 2001

Due to international law the Antarctic is currently the best protected large ecosystem on earth, providing the opportunity for scientific research into processes of both regional and global importance. However, it is impossible to carry out research activities without minor disturbances to the environment. The Weddell Sea with its shelf inhabiting fauna can be considered to be representative for the entire Antarctic shelf with exceptions. It has generally escaped major anthropogenic impact but it is the only area in the high latitude Antarctic where long-term research fishing has been carried out. There are two main results combining aspects of nature conservation and benthos research. Firstly, the use of dredges has clearly decreased over the last two decades, whilst the use of non-invasive underwater photography and video has significantly increased. Secondly, during the same period icebergs destroyed an area of the seafloor and its fauna more than 2000-times greater than the area affected by research trawls. The increased use of imaging methods, Remotely Operated Vehicles (ROV) and other modem instruments, as well as statistically based and coordinated sampling strategies can contribute to both a better understanding of ecosystem function and to an ongoing reduction in anthropogenic impact.

• 한국수산과학회지
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• 제27권2호
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• pp.183-192
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• 1994

대서양 남빙양 새우의 주된 분포역은 South George Island, Laurie/Coronation Islands와 Livingston/King George Islands 지역으로 공간적인 구분을 뚜렷이 하였다. 어획 수심은 층에서 150 m층까지 달했고, 10 m층으로 구분한 단위노력당어획량의 수직 분포는 층간에 큰 차이가 없었으나 수심이 깊어 질수록 낮아지는 경향을 보였다. 수온과 단위노력당 어획량의 관계로 부터 남빙양 새우는 주로 $0.8{\sim}l.0^{\circ}C$ 범위에서 높은 밀도를 나타내었다. 남빙양 새우의 암수별 체장 조성은 큰 차이를 보여 숫컷의 비율은 작은 체장에서, 암컷의 비율은 큰 체장에서 각각 높았다. 두흉갑장과 체장관계, 체장과 체중관계가 암수별로 추정되었다. 암수별 성비조성은 숫컷이 $60.3\%$, 암컷이 $39.7\%$로서 유의한 차이를 나타내었다.

• Ocean and Polar Research
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• 제25권4호
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• pp.625-631
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• 2003

While phytoplankton diversity and productivity in the Southern Ocean has been widely studied in recent years, most attention has been given to elucidating environmental factors that affect the dynamics of micro-plankton (mainly diatoms) and nano-plankton (mainly Phaeocystis antarctica). Only limited effects have been given to studying the occurrence and the potential risks associated with the blooming of dinoflagellates in the relevant waters. This study focused on the appearance and toxicological characteristics of a toxic dinoflagellate, Alexandrium tamarense, identified and isolated from the Drake Passage in a research cruise from November to December 2001 The appearance of A. tamarense in the Southern Ocean indicates the risk of a paralytic shellfish poisoning (PSP) outbreak there and is therefore of scientific concern. Results showed that while the overall quantity of A. tamarense in water samples from 30meters below the sea surface often comprised less than 0.1% of the total population of phytoplankton, the highest concentration of A. tamarense (20 cells $L^{-1}$) was recorded in the portion of the Southern Ocean between the southern end of South America and the Falkland Islands. Waters near the Polar Front contained the second highest concentrations of 10-15 cells $L^{-1}$. A. tamarense was however rarely found in waters near the southern side of the Polar Front, indicating that cold sea temperatures near the Antarctic ice does not favor the growth of this dinoflagellate. One strain of A. tamarense from this cruise was isolated and cultured for further study in the laboratory. Experiments showed that this strain of A. tamarense has a high tolerance to temperature variations and could survive at temperatures ranging from $5-26^{\circ}C$. This shows the cosmopolitan nature off. tamarense. With regard to the algal toxins produced, this strain of A. tamarense produced mainly C-2 toxins but very little saxitoxin and gonyailtoxin. The toxicological property of this A. tamarense strain coincided with a massive death of penguins in the Falkland Islands in December 2002 to January 2003.