• Title/Summary/Keyword: Svalbard

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Plant co-occurrence patterns and soil environments associated with three dominant plants in the Arctic

  • Deokjoo Son
    • Journal of Ecology and Environment
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    • v.47 no.1
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    • pp.1-13
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    • 2023
  • Background: The positive effects of Arctic plants on the soil environment and plant-species co-occurrence patterns are known to be particularly important in physically harsh environments. Although three dominant plants (Cassiope tetragona, Dryas octopetala, and Silene acaulis) are abundant in the Arctic ecosystem at Ny-Ålesund, Svalbard, few studies have examined their occurrence patterns with other species and their buffering effect on soil-temperature and soil-moisture fluctuation. To quantify the plant-species co-occurrence patterns and their positive effects on soil environments, I surveyed the vegetation cover, analyzed the soil-chemical properties (total carbon, total nitrogen, pH, and soil organic matter) from 101 open plots, and measured the daily soil-temperature and soil-moisture content under three dominant plant patches and bare soil. Results: The Cassiope tetragona and Dryas octopetala communities increased the soil-temperature stability; however, the three dominant plant communities did not significantly affect the soil-moisture stability. Non-metric multidimensional scaling separated the sampling sites into three groups based on the different vegetation compositions. The three dominant plants occurred randomly with other species; however, the vegetation composition of two positive co-occurring species pairs (Oxyria digyna-Cerastium acrticum and Luzula confusa-Salix polaris) was examined. The plant species richness did not significantly differ in the three plant communities. Conclusions: The three plant communities showed distinctive vegetation compositions; however, the three dominant plants were randomly and widely distributed throughout the study sites. Although the facilitative effects of the three Arctic plants on increases in the soil-moisture fluctuation and richness were not quantified, this research enables a deeper understanding of plant co-occurrence patterns in Arctic ecosystems and thereby contributes to predicting the shift in vegetation composition and coexistence in response to climate warming. This research highlights the need to better understand plant-plant interactions within tundra communities.

Observations for the Ionosphere Using European Incoherent Scatter (EISCAT) in the Dayside Polar Cap/Cusp and Auroral Region

  • Geonhwa Jee;Eun-Young Ji;Eunsol Kim;Young-Sil Kwak;Changsup Lee;Hyuck-Jin Kwon;Ji-Eun Kim;Young-Bae Ham;Ji-Hee Lee;Jeong-Han Kim;Tae-Yong Yang;Hosik Kam
    • Journal of Astronomy and Space Sciences
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    • v.40 no.1
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    • pp.1-10
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    • 2023
  • Korea Polar Research Institute (KOPRI) and Korea Astronomy and Space Institute (KASI) have been participating in the European Incoherent Scatter (EISCAT) Scientific Association as an affiliate institution in order to observe the polar ionosphere since 2015. During the period of December 16-21, 2016 and January 3-9, 2018, the observations for the polar ionospheric parameters such as the electron density profiles, ion drift, and electron/ion temperature are carried out in the polar cap/cusp region by the EISCAT Svalbard radar (ESR). The purpose of the observations is to investigate the characteristic of the winter ionosphere in the dayside polar cap/cusp region. In this paper, we briefly report the results of the ESR observations for winter daytime ionosphere and also the simultaneous observations for the ionosphere-thermosphere system together with the balloon-borne instrument High-Altitude Interferometer WIND Experiment (HIWIND) performed by the High Altitude Observatory (HAO), National Center for Atmospheric Research (NCAR). We further introduce our research activities using long-term EISCAT observations for the occurrence of ion upflow and the climatology of the polar ionospheric density profiles in comparison with the mid-latitude ionosphere. Finally, our future research plans will briefly be introduced.

Microbial Community of the Arctic Soil from the Glacier Foreland of Midtre Lovénbreen in Svalbard by Metagenome Analysis (북극 스발바르 군도 중앙로벤 빙하 해안 지역의 토양 시료 내 메타지놈 기반 미생물 군집분석)

  • Seok, Yoon Ji;Song, Eun-Ji;Cha, In-Tae;Lee, Hyunjin;Roh, Seong Woon;Jung, Ji Young;Lee, Yoo Kyung;Nam, Young-Do;Seo, Myung-Ji
    • Microbiology and Biotechnology Letters
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    • v.44 no.2
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    • pp.171-179
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    • 2016
  • Recent succession of soil microorganisms and vegetation has occurred in the glacier foreland, because of glacier thawing. In this study, whole microbial communities, including bacteria, archaea, and eukaryotes, from the glacier foreland of Midtre Lovénbreen in Svalbard were analyzed by metagenome sequencing, using the Ion Torrent Personal Genome Machine (PGM) platform. Soil samples were collected from two research sites (ML4 and ML7), with different exposure times, from the ice. A total of 2,798,108 and 1,691,859 reads were utilized for microbial community analysis based on the metagenomic sequences of ML4 and ML7, respectively. The relative abundance of microbial communities at the domain level showed a high proportion of bacteria (about 86−87%), whereas archaeal and eukaryotic communities were poorly represented by less than 1%. The remaining 12% of the sequences were found to be unclassified. Predominant bacterial groups included Proteobacteria (40.3% from ML4 and 43.3% from ML7) and Actinobacteria (22.9% and 24.9%). Major groups of Archaea included Euryarchaeota (84.4% and 81.1%), followed by Crenarchaeota (10.6% and 13.1%). In the case of eukaryotes, both ML4 and ML7 samples showed Ascomycota (33.8% and 45.0%) as the major group. These findings suggest that metagenome analysis using the Ion Torrent PGM platform could be suitably applied to analyze whole microbial community structures, providing a basis for assessing the relative importance of predominant groups of bacterial, archaeal, and eukaryotic microbial communities in the Arctic glacier foreland of Midtre Lovénbreen, with high resolution.

Two-dimensional Velocity Measurements of Uvêrsbreen Glacier in Svalbard Using TerraSAR-X Offset Tracking Approach (TerraSAR-X 위성레이더 오프셋 트래킹 기법을 활용한 스발바르 Uvêrsbreen 빙하의 2차원 속도)

  • Baek, Won-Kyung;Jung, Hyung-Sup;Chae, Sung-Ho;Lee, Won-Jin
    • Korean Journal of Remote Sensing
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    • v.34 no.3
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    • pp.495-506
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    • 2018
  • Global interest in climate change and sea level rise has led to active research on the velocities of glaciers. In studies about the velocity of glaciers, in-situ measurements can obtain the most accurate data but have limitations to acquire periodical or long-term data. Offset tracking using SAR is actively being used as an alternative of in-situ measurements. Offset tracking has a limitation in that the accuracy of observation is lower than that of other observational techniques, but it has been improved by recent studies. Recent studies in the $Uv{\hat{e}}rsbreen$ glacier area have shown that glacier altitudes decrease at a rate of 1.5 m/year. The glacier displacement velocities in this region are heavily influenced by climate change and can be important in monitoring and forecasting long-term climate change. However, there are few concrete examples of research in this area. In this study, we applied the improved offset tracking method to observe the two-dimensional velocity in the $Uv{\hat{e}}rsbreen$ glacier. As a result, it was confirmed that the glacier moved at a maximum rate of 133.7 m/year. The measruement precisions for azimuth and line-of-sight directions were 5.4 and 3.3 m/year respectively. These results will be utilized to study long-term changes in elevation of glaciers and to study environmental impacts due to climate change.

Multiple Shoot Induction from Radicle-derived Callus and in Vitro Propagation of Silene Acaulis Subsp. Arctics (극지식물 Silene acaulis subsp. arctica의 유근 유래 캘러스로부터 다신초 유도와 기내 증식)

  • Seo, Hyo-Won;Yi, Jung-Yoon;Park, Young-Eun;Kang, Sung-Ho;Chung, Ho-Sung;Kim, Ji-Hee
    • Journal of Plant Biotechnology
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    • v.33 no.4
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    • pp.303-307
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    • 2006
  • We describe here an efficient in vitro propagation method of Silene acaulis subsp. arctica (Caryophyllaceae), one of the higher arctic angiosperms, through the multiple shoot regeneration after callus induction from the radicle. The seeds of S. acaulis subsp. arctica collected from Svalbard, the Norwegian Arctic, were germinated and calli were induced from the radicle on solid MS media supplemented with 0.25mg/L 2,4-D and 1mg/L $GA_3$ at both $10{\pm}1^{\circ}C\;and\;23{\pm}1^{\circ}C$ Two weeks after callus induction, the multiple shoots were efficiently regenerated on the MS media supplemented with 0.25 g/L BA and 0.05mg/L HPh. The total biomass increment of regenerated shoots increased most efficiently of S. acaulis subsp. afctica was showed the maximum efficiency in at $23{\pm}1^{\circ}C$ on 1/2 MS salt strength. The multiple regenerated plantlets of S. acaulis subsp. arctics were grown to normal plants on soil.

Study on the Community Structure of Sublittoral Meiofauna in the Barents Sea in Summer 2002, Arctic Ocean (2002년 하계 북극 바렌츠해 연안지역의 중형저서생물 군집 구조에 관한 연구)

  • Lee Kang Hyun;Chung Kyung-Ho;Kang Sung-Ho;Lee Wonchoel
    • Korean Journal of Environmental Biology
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    • v.23 no.3 s.59
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    • pp.257-268
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    • 2005
  • Meiofauna community was surveyed in the Arctic Ocean. Sediment samples were collected from six stations in the east Barents Sea and from five stations in Kongsfjorden, Svalbard during summer 2002. Eight taxa of meiofauna were identified in the Barents Sea. Meiofauna abundance ranged from 245 to 906 indiv.10 $cm^{-2}$ (mean 580 indiv.10 $cm^{-2}$) and total biomass varied from 23 and 404 ${\mu}gC10cm^{-2}$ (mean 184 ${\mug}C10cm^{-2}$) in the Barent Sea. Nematode predominated in meiofauna comprising $95.2\%$ of total abundance and $66.4\%$ of biomass. Copepods, polycheats and sarcomastigophonans were also dominant in the study area. Nine taxa of meiofauna were identified in Kongsfiorden. Meiofauna abundance ranged from 103 to 513 indiv.10 $cm^{-2}$ (mean 292 indiv.10 $cm^{-2}$) and biomass varied from 13 and 196{\mu}gC10\;cm^{-2}$ (mean 94{\mu}gC10\;cm^{-2}$) in the Kongsfiorden. Nematodes predominated in meiofauna, comprising $64.1\%$ of abundance and $64.3\%$ biomass. Copepods, polychaets, and kinorhyncha were also dominant in the study area. The meiofauna abundances from both the study areas well match with the previous reports from the various regions including the temperate areas. However the occurred taxa in the present study are only a half comparing with the reports from temperate zone. Meiofauna abundance, biomass, diversity index and species richness were much higher than in the coastal which were strongly affected by fresh water run off in the Barents Sea. The stations affected by chlorophyll had high abundance and biomass, but low diversity index and spices richness in Kongsfiorden.