• Title, Summary, Keyword: Antarctica

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Efficient Registration Plan of Place Names for Reinforcement of Active Region in Antarctica

  • Yun, Hee Cheon;Park, Joon Kyu;Lee, Jong Sin
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.31 no.6_2
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    • pp.549-557
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    • 2013
  • The Antarctica continent does not belong to any countries so that a place in the region has some different place names between countries. Korea gave Korean place names to the places around the King Sejong Station, and the names have since been used by Korean researchers on the Antarctic. However, they have yet to be registered officially at CGA(Composite Gazetteer of Antarctica) by November 2010. Therefore, to prepare for the possible disputes over territorial claims in Antarctica and to expand and specify activity areas, this research tries to analyze the present condition of advanced countries' committees on place names of Antarctica, their procedures of registering names and their registration criteria, and thereby suggest an efficient plan for registering place names of Antarctica. If the plan suggested in this research is actively reviewed and applied, it will be able to make a great contribution to advancing the place names of Antarctica and research on the Antarctic.

Waterlogging induced oxidative stress and the mortality of the Antarctic plant, Deschampsia antarctica

  • Park, Jeong Soo;Lee, Eun Ju
    • Journal of Ecology and Environment
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    • v.43 no.3
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    • pp.289-296
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    • 2019
  • We investigated the mortality and the oxidative damages of Deschampsia antarctica in response to waterlogging stress. In field, we compared the changes in the density of D. antarctica tuft at the two different sites over 3 years. The soil water content at site 2 was 6-fold higher than that of site 1, and the density of D. antarctica tuft decreased significantly by 55.4% at site 2 for 3 years, but there was no significant change at site 1. Experimental results in growth chamber showed that the $H_2O_2$ and malondialdehyde content increased under root-flooding treatment (hypoxic conditions-deficiency of $O_2$), but any significant change was not perceptible under the shoot-flooding treatment (anoxic condition-absence of $O_2$). However, total chlorophyll, soluble sugar, protein content, and phenolic compound decreased under the shoot-flooding treatment. In addition, the catalase activity increased significantly on the 1st day of flooding. These results indicate that hypoxic conditions may lead to the overproduction of reactive oxygen species, and anoxic conditions can deplete primary metabolites such as sugars and protein in the leaf tissues of D. antarctica. Under present warming trend in Antarctic Peninsula, D. antarctica tuft growing near the shoreline might more frequently experience flooding due to glacier melting and inundation of seawater, which can enhance the risk of this plant mortality.

Macroalgal Flora of Maxwell Bay, King George Island, Antarctica: II. Rhodophyta

  • Kim, Ji-Hee;Chung, Ho-Sung;Oh, Yoon-Sik;Lee, In-Kyu
    • Ocean and Polar Research
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    • v.23 no.4
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    • pp.347-360
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    • 2001
  • This study examined the taxonomic composition of marine benthic algal flora from Maxwell Bay, King George Island, Antarctica, collected between January 1988 and January 1995. The rhodophyte specimens collected and examined included a total of 20 genera and 20 species of red algae. Of these, 2 species, Kallymenia antarctica Hariot and Pantoneura plocamioides Kylin, were recorded in Maxwell Bay for the first time. Taxonomic keys for the rhodophytes are also provided.

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Effect of Solar Irradiances on Growth and Pigmentation of Antarctic Red Algae, Kallymenia antarctica and Palmaria decipiens

  • Han, Tae-Jun;Han, Young-Seok;Lee, Min-Soo;Park, Jin-Hee;Cho, Man-Gi;Koo, Jae-Gun;Kang, Sung-Ho
    • Ocean and Polar Research
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    • v.25 no.4
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    • pp.427-435
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    • 2003
  • Growth and pigment responses to different levels of solar radiation with or without ultraviolet (UV)-B component $({\lambda}=280-315nm)$ were investigated in Antarctic rhodophytes, Kallymenia antarctica and Palmaria decipiens, collected around King George Island during the summer of 2000. In K. antarctica specific growth rate, based on thallus area or fresh weight, decreased with increasing solar irradiances while P. decipiens were relatively insensitive to the effects of light. It is noticeable that the presence or absence of UV-B had no significant effect on growth for either species. However, K. antarctica showed a more pronounced reduction in chlorophyll (Chl a) concentrations at higher irradiances in the presence of UV-B. In P. decipiens, Chl a concentrations did not differ despite radiation level fluctuations being lower albeit than initial measurements. Thallus thickness was greater in K. antarctica than in P. decipiens. There were higher relative amounts of UV-absorbing pigments (UVAPs) in P. decipiens than in K, antarctica. The single absorbance peak obtained from the methanol extracts was resolved into three (316,332 and 346nm) in K. antarctica and four peaks (315,326,333 and 349 nm) in Palmaria as a result of the fourth-derivative. After 7 days exposure to solar radiation, the amount of UVAPs in K. antarctica was significantly reduced to a similar degree at all light levels, whereas that of P. decipiens remained unchanged except at 5% of surface irradiance. High performance liquid chromatography (HPLC) analysis of purified extracts indicated that P. decipiens possesses porphyra-334 in addition to three other mycosporine-like anlino acids (MAAs; asterina-330, palythine, shinorine), which are commonly present in K. antarctica. Significantly lower tolerance of K. antarctica to high levels of solar radiation may be connected with its usual absence in the eulittoral, while the active growth and elastic pigment responses of P. decipiens over a wide range of solar irradiance levels up to full sunlight seems to correspond well with its wide vertical distribution from rock pools down to 25-30m.

Distribution Pattern of Deschampsia antarctica, a Flowering Plant Newly Colonized around King Sejong Station in Antarctica (남극 세종기지 주변에 새로이 정착한 현화식물 남극좀새풀 (Deschampsia antarctica)의 개체군 공간분포)

  • Kim, Ji-Hee;Chung, Ho-Sung
    • Ocean and Polar Research
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    • v.26 no.1
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    • pp.23-32
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    • 2004
  • As a baseline survey for long-term monitoring on environmental change around the Antarctic King Sejong Station, distribution pattern of Deschampsia antarctica Desv., a flowering plant newly colonized were investigated qualitatively and quantitatively in both austral summer 2002 and 2003. Dispersal of the seeds and vegetative leaves by skuas might lead to the colonization into this area from neighbors in Maxwell Bay. The pioneer populations were observed around ponds and a stream of the Sejong Point in January 2002, and the maximum dispersal area was four times expanded after a year. Most of the populations were formed on the stable and well-drained substrate, which consisted of moss carpet of Sanionia georgico-uncinata (65%) and pebbles (25%), while only a few young individuals were observed on the unstable and watertight silt-sandy area. Especially, S. georgico-uncinata was being effectively utilized as their primary substrate with the soft, coarse and water-contained leaves. Also the perennial mature plants of D. antarctica were mainly formed on the moss carpet rather than pebbles. A few individuals were grown on other mosses of Polytrichastrum alpinum, Bryum pseudotriquetrum, Pohlia cruda, and Conostomum magellanicum and on a liverwort of Cephaloziella varians. We expect that dispersal of D. antarctica and the following succession to grass field will be countinuously and dynamically proceeded in this area, with the characteristics of ecological niche against the initial moss populations, on the similar continuity of environmental conditions. The continuous observations are needed with establishment of database on environmental change of micro-habitats, e.g. the water content and nutrients of soil and the underground temperature and permafrost.

Diversity of the Lichenized Fungi in King George Island, Antarctica, Revealed by Phylogenetic Analysis of Partial Large Subunit rDNA Sequences

  • Lee, Jin-Sung;Lee, Hong-Kum;Hur, Jae-Seoun;Andreev, Mikhail;Hong, Soon-Gyu
    • Journal of Microbiology and Biotechnology
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    • v.18 no.6
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    • pp.1016-1023
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    • 2008
  • Lichens are predominant and important components of flora in the terrestrial ecosystem of Antarctica. However, relatively few researches on the phylogenetic position of Antarctic lichen-forming fungi have been accomplished. In this study, partial sequences of nuclear large subunit rDNAs from 50 Antarctic specimens were obtained and the phylogeny was reconstructed. Antarctic lichen species were distributed in 4 orders, including the monophyletic order Agyrales, paraphyletic orders Pertusariales and Teloschistales, and polyphyletic order Lecanorales. Species diversity was highest in the order Lecanorales, followed by Teloschistales and Pertusariales. Based on the phylogeny and sequence similarity analyses, it is proposed that the taxonomy of Stereocaulon alpinum, Physcia caesia, Usnea aurantiacoatra, and Cladonia species should be revised by careful examination of their phenotypic and molecular characteristics. Six species known to be endemic to Antarctica, Catillaria corymbosa, Himantormia lugubris, Leptogium puberulum, Pertusaria pertusa, Rhizoplaca aspidophora, and Umbilicaria antarctica, formed unique lineages, implying independent origins in the Antarctic area.

Mineral resources potential and evaluation of its exploration in Northern Victoria Land, Antarctica (남극 북빅토리아랜드의 광물 자원 존재 및 탐사 가능성 평가)

  • Kim, Yeongmin;Lee, Insung;Lee, Jong Ik;Woo, Jusun;Kim, Taewoo
    • Journal of the Geological Society of Korea
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    • v.53 no.4
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    • pp.555-565
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    • 2017
  • Antarctica was a part of Gondwana Supercontinent with Australia, Africa, South America and India and has a great potential on mineral resources. Evaluation and exploration of mineral resources in Antarctica is difficult due to its severe climate and widespread snow/ice-covered area. The Protocol of Environmental Protection to the Antarctic Treaty also prohibits any activities related to the resources exploration and development without scientific purposes. Before the effectuation of the Protocol, there had been researches and activities for mineral resource evaluation of Antarctica. Especially, exploration and evaluation of uranium deposits in Antarctica had been carried out mainly by U.S. Antarctic Research Program. There are geographic, climatic, technical, economic and environmental difficulties for mineral resources exploration in Antarctica. For resource depletion circumstances in the future, it is necessary to approach the mineral exploration in Antarctica from scientific viewpoint. With the completion of Jang Bogo station in Antarctica, the area with high mineral resources potential in Northern Victoria Land will be narrowed by the field survey and geochemical analysis and focused investigation will be carried out.

A Study of Modular Architecture's Design to Dwelling Environment in Antarctica (극한지 모듈러 건축물의 설계, 시공 및 거주환경에 대한 연구)

  • Lee, Won-Hak;Song, Young-Hak;Lim, Seok-Ho
    • Journal of the Korean housing association
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    • v.25 no.2
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    • pp.11-18
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    • 2014
  • This study looked at designing, building and operating temporary camp, the first structures that South Korea built in the Antarctica. While there may be differences in accordance with the topography, ground surfaces in the Antarctica are covered broken stones, glaciers and snow. Hence, such topographical characteristics should be taken into account when conducting any construction work. To ensure successful assembly construction in the Antarctica using modules, prior trial assembly work should be done in Korea to identify any possible trouble in the actual construction process. Assuming that the workers will have to spend at least one winter in the temporary camp, the work will be more severely affected by adverse weather conditions and snow drift, resulting in the need to clear snow. This can be by designing roofs with curved surfaces. Also, quantitative effects will need to be verified through simulation and actual measurement. It will also be necessary to assess the camp's thermal environment and examine its air-conditioning methods. To identify the temporary camp's thermal system, the temperatures and humidities were measured, and the heating system was designed not to offer automatic control or desired value selection functions.

Benthic Organisms and Environmental Variability in Antarctica: Responses to Seasonal, Decadal and Long-term Change

  • Clarke, Andrew
    • Ocean and Polar Research
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    • v.23 no.4
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    • pp.433-440
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    • 2001
  • Marine organisms in Antarctica live in an environment which exhibits variability in physical processes over a wide range of temporal scales, from seconds to millennia. This time scale tends to be correlated with the spatial scale over which a given process operates, though this relationship is influenced by biology. The way organisms respond to variability in the physical environment depends on the time-scale of that variability in relation to life-span. Short-term variations are perceived largely as noise and probably have little direct impact on ecology. Of much greater importance to organisms in Antarctica are seasonal and decadal variations. Although seasonality has long been recognised as a key feature of polar environments, the realization that decadal scale variability is important is relatively recent. Long-term change has always been a feature of polar environments and may be a key factor in the evolution of the communities we see today.

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Diatom Succession Representing the Paleoclimatic Change from Laminated Sediments around Antarctica (남극 엽층리 퇴적물로부터 규조 종을 이용한 고기후 변화 연구)

  • Bak, Young-Suk;Yoon, Ho Il;Yoo, Kyu-Cheul;Lee, Young-Up
    • Journal of the Korean earth science society
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    • v.36 no.2
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    • pp.190-197
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    • 2015
  • This study investigated the paleoclimatic change using diatoms that were extracted from the high-resolution laminated layers of diatom ooze sediment cores GC08-EB01 in the eastern basin of the Bransfield Strait, Antarctica. The range of diatom valves per gram of dry sediment was from $0.4-4.2{\times}10^8g^{-1}$ in quantitative diatom assemblage analysis. Laminations are classified using visually dominant diatom species and terrigenous content. Biogenic diatom ooze laminae characterised by bloom of Corethron crilophilum, Eucampia antarctica, Fragilariopsis curta, F. kerguelensis, Odontella weissflogii, Proboscia inermis, R. styliformis, Thalassiosira antarctica, and Chaetoceros resting spores. Terrigenous laminae characterised by mixed diatom assemblage. The ratio of (Fragilariopsis curta+F. cylindrus)/Thalassiosira antarctica increase in horizons, suggesting increased sea-ice cover in the study area during the late Holocene (cold events). As a result, five cold events are identified on the basis of frequency of the critical taxa throughout the section.