• Animal Systematics, Evolution and Diversity
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• v.36 no.4
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• pp.396-399
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• 2020

The Antarctic freshwater copepod, Boeckella poppei (Mrazek, 1901), has the widest range of distribution extending from southern South America to Antarctic continent, among all Boeckella species. Boeckella poppei is the only freshwater copepod known to be inhabiting the Antarctic continent. In present study, we analyzed the DNA barcodes of the mitochondrial cytochrome c oxidase subunit I (COI) gene of B. poppei from King George Island, Antarctica. The intraspecific genetic distances varied from 0% to 13% and interspecific genetic distances ranged from 11% to 14%. The overlap of DNA barcode gap suggests careful threshold-based delimitation of species boundaries.

• Journal of Marine Life Science
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• v.4 no.1
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• pp.22-28
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• 2019

The bacterial diversity of an Antarctic hard coral, Errina fissurata, was examined by isolating bacterial colonies from crushed coral tissue and by sequencing their 16S rRNA gene. From the analyzed results, the bacteria were classified as Actinobacteria (56%), Firmicutes (35%) and Proteobacteria (9%). The thirty-four isolates were cultured in liquid media at different temperatures and their growth was assessed over time. The majority of the isolates displayed their highest growth rate at 25℃ during the first three days of cultivation, even though the coral was from a cold environment. Nevertheless, strains showing their highest growth rate at low temperatures (15℃ and 4℃) were also found. This study reports the composition of an Antarctic hard coral-associated culturable bacterial community and their growth behavior at different temperatures.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.E2
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• pp.85-96
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• 2000

The concentrations of Pb, Mn, Al and Na were measured from a total of 26 snow samples collected from a 1.5-m deep snow pit in Livingston Island, South Shetland Islands, at the northern tip of the Antarctic Peninsula. Ore sampling location is great concern, because of its proximity to the southern extremity of south America, a candidate for the source regions of pollutant aerosols entering Antarctica. The mean concentrations of Pb and Mn were found to be 4.97 pg g(sup)-1 and 20.6 pgg(sup)-1, respectively. These concentrations levels are similar to those reported for recent snow at other Antarctic sites with pronounced spring maxima for both metals. Contributions form natural sources are estimated to be minor (∼16%) for Pb. For Mn, on the other hand, contribution from rock and soil dusts is found to be very important. Excess Pb over Pb from natural sources is likely to be anthropogenic, especially from South Americal. Our results show that yearly Pb fallout flux is much greater in Antarctic coastal areas than at other Antarctic locations far from the coast , indicating that the transport and deposition patterns of pollutant aerosols are not simple is Antarctica. It is also suggested that the recycling of anthropogenic Pb in seawater to the atmosphere could significantly contribute to the Pb fallout flux in the Antarctic coastal regions.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.2
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• pp.183-192
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• 1994

Spatial distribution patterns of Antarctic krill, Euphausia superba in the Atlantic Ocean sector were seasonally divided into three or four regions; South George Island, Laurie/Coronation Islands and Livingston/King George Islands. Antarctic krill were caught from the surface to about 150 m in depth. The vertical distribution of catch per hour (CPUE) did not show much differences between the 10 m layers, but there were gradually poorer CPUEs as trawl depth increased. It was estimated from relationship between water temperature and CPUE that the Antarctic krill abundance was maximal at water temperatures of $0.8{\sim}1.0^{\circ}C$. The length compositions of Antarctic krill showed that female fish were, on an average, significantly larger than males. Relationship between carapace length and body length, and body length-body weight relationship were well fitted. Sex ratio was $60.3\%$ for male and $39.7\%$ for female with significant difference at the $5\%$ level.

• Ocean and Polar Research
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• v.24 no.3
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• pp.227-236
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• 2002

For ten firn cores, from both the eastern and the western side of Lambert Glacier basin (LGB), snow accumulation rate and isotopic temperature were measured far the recent 50 years. Results show that snow accumulation for five cores over the eastern side of LGB (GC30, GD03, GD15, DT001, and DT085) at Wilks Land and Princess Elizabeth Land increases, whereas it decreases at the western side (Core E, DML05, W200, LGB 16, and MGA) at Dronning Maud Land, Mizuho Plateau and Kamp Land. For the past decades, the increasing rate was $0.34-2.36kg\;m^{-2}a^{-1}$ at the eastern side and the decreasing rate was $-0.01\;-\;-2.36kg\;m^{-2}\;a^{-1}$ at the western side. Temperatures at the eastern LGB were also increased with the rate of $0.02%o\;a^{-l}$. At the western LGB it was difficult to see clear trends, which were confirmed by Instrumental temperature records at coastal stations. Although statistic analysis and modeling results display that both surface temperature and accumulation rate has increased trends in Antarctic ice sheet during 1950-2000, the regional distributions were much more different for different geographic areas. We believe that ice-core records at Wilks Land and Princess Elizabeth Land reflect the real variations of SST and moisture change in the southern India Ocean. For the Kamp Land and Dronning Maud Land, however circulation pattern was different, by which the climate was more complicated. The International Trans-Antarctic Scientific Expedition (ITASE) aimed to reveal an overall spatial pattern of climate change over Antarctic ice sheet for the past 200 years. This study points the importance of continental to regional circulation to annual-decadal scale climate change in Antarctica.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.4
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• pp.435-443
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• 2018

The Antarctic krill Euphausia superba is important commercially and ecologically as a basic component of the Antarctic Ocean ecosystem. To manage this resource, it is important to determine the distribution and standing of krill in the water layer. Acoustic methods can capture information about the entire water layer quickly. Acoustic surveys were conducted from March 3 to March 14, 2017, using the commercial fishing boat Sejong (7,765 tons). Acoustic systems with a frequency of 38 kHz and a 200 kHz commercial echo sounder (ES70, Simrad, Norway) were used and the acquired data were processed using post processing software. The density and standing of Antarctic krill were determined using the two-frequency difference method, using the characteristics of two frequencies. To compare the frequency difference of krill, the method using the frequency difference according to the krill length, recommended by the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) and the values extracted according to the krill length at survey stations where only krill were collected during the study period, were compared. The frequency difference ranges were 3.96-5.91 dB and -3.0~13.8 dB, respectively.

• Journal of Ocean Engineering and Technology
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• v.5 no.2
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• pp.171-171
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• 1991

• Journal of the Korean Geophysical Society
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• v.3 no.3
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• pp.141-152
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• 2000

In the vicinity of the Antarctic-Scotia plate boundary off Elephant Island(EI), geophysical data(multichannel seismic and gravity data) reveal rapid structural variation of the Shackleton Fracture Zone(SFZ) along its strike. The SFZ ridge terminates in front of the Antarctic Peninsula margin, whereas the transform fault of the SFZ continues farther southeast near EI and the width of the SFZ broadens toward the southeast. Accordingly, the SFZ transform fault changes its morphology along its strike as (1) a graben structure along the high Shackleton ridge in Drake Passage, (2) a half-graben structure in oceanic crust just southeast of the Antarctic-Scotia plate boundary, and (3) splay faults deforming the margin of EI. Two phases of tectonic deformation are clearly observed along the transform fault. Major extensional deformation had formed a large-scale half-graben during roughly about $10{\sim}20$ Ma when Drake Passage had opened. And then, the Shackleton fault has been reactivated with reverse sense, which has been caused by recent convergence between Antarctic and Scotia plates due to westward movement of the Scotia plate since 6 Ma.

• Journal of Astronomy and Space Sciences
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• v.34 no.3
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• pp.207-212
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• 2017

During the last glacial-interglacial transition, there were multiple intense climatic events such as the Bølling-Allerød warming and Younger Dryas cooling. These events show abrupt and rapid climatic changes. In this study, the climate events and cycles during this interval are examined through wavelet analysis of Arctic and Antarctic ice-core $^{18}O$ and tropical marine $^{14}C$ records. The results show that periods of ~1383-1402, ~1029-1043, ~726-736, ~441-497 and ~202-247 years are dominant in the Arctic region, whereas periods of ~1480, ~765, ~518, ~311, and ~207 years are prominent in the Antarctic TALDICE. In addition, cycles of ~1019, ~515, and ~209 years are distinct in the tropical region. Among these variations, the de Vries cycle of ~202-209 years, correlated with variations in solar activity, was detected globally. In particular, this cycle shows a strong signal in the Antarctic between about 13,000 and 10,500 yr before present (BP). In contrast, the Eddy cycle of ~1019-1043 years was prominent in Greenland and the tropical region, but was not detected in the Antarctic TALDICE records. Instead, these records showed that the Heinrich cycle of ~1480 year was very strong and significant throughout the last glacial-interglacial interval.

• Ocean and Polar Research
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• v.38 no.3
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• pp.209-224
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• 2016

The purpose of this study is to analyze research activities related to Antarctic science through a bibliographic study and to understand and evaluate the implications. This study is based on 78,445 articles which were retrieved from the Science Citation Index(SCI) database during the period 1998-2015. Through a quantitative analysis and a Social Network Analysis, we made several findings and drew out the implications. First, many countries, in general, have increased multi-national research cooperation in order to enhance research productivity. However, Korea's cooperative research activity is below the average level. Second, considering the 4 centrality indexes, which are derived from the SNA, Korea had a lower score in terms of centrality indexes. Based on these findings, Korea should formulate a more dynamic or proactive strategy in order to enhance its participation in international research cooperation efforts. Korea, the 10th country to build two or more research bases in Antarctica, should make greater efforts to bring the appropriate level of the phase.