Consulta: subjectFacets:"Antarctica"
Registros recuperados: 78
Data/hora: 05/06/2024 17:15:44

Checklist of the Discomycetes (Fungi) of Patagonia, Tierra del Fuego and adjacent antarctic areas
Provedor de dados: 66
Autores: Gamundí,Irma J.; Minter,David W.; Romero,Andrea I.; Barrera,Viviana A.; Giaiotti,Andreina L.; Messuti,María I.; Stecconi,Marina.
Information about fungi of the orders Cyttariales, Helotiales, Ostropales, Pezizales, Rhytismatales and Thelebolales (Discomycetes) collected in Patagonia, Tierra del Fuego and adjacent antarctic areas (Patagonia), and information about their associated organisms was located, abstracted, keyboarded, edited and validated. The largest single information sources were dried reference collections in Argentina and elsewhere, and published information as listed in this work's bibliography. Other records were derived from fresh collections, other reference collections and field observations. Information is stored in a computerized system of relational databases for taxonomic, nomenclatural, bibliographic and biological observations data. This system allows storage...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Discomycetes; Patagonia; Tierra del Fuego; Antarctica; Checklist.
Ano: 2004
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0011-67932004000100006

Recent records of the Atlantic Petrel(Pterodroma incerta) for the Atlantic Regionof the Southern Ocean and Antarctica
Provedor de dados: 68
Autores: Orgeira,José Luis.
New records of the Atlantic Petrel (Pterodroma incerta) at-sea for the Atlantic region of the Southern Ocean and Antarctica were reported during summer 2009 and 2010. Most of these observations occurred outside the accepted range for this species and improve the available information on its distribution. The Atlantic Petrel has been regularly recorded north and south of the Antarctic Convergence for more than 30 years, although these records are still considered casual and not part of their usual pelagic range.
Tipo: Info:eu-repo/semantics/other
Palavras-chave: Antarctica; Atlantic Petrel; Pterodroma incerta; South Atlantic Ocean.
Ano: 2011
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0073-34072011000200011

Antibacterial activity of the Antarctic bacterium Janthinobacterium sp: SMN 33.6 against multi-resistant Gram-negative bacteria
Provedor de dados: 69
Autores: Asencio,Geraldine; Lavin,Paris; Alegría,Karen; Domínguez,Mariana; Bello,Helia; González-Rocha,Gerardo; González-Aravena,Marcelo.
Background The increment of resistant strains to commonly used antibiotics in clinical practices places in evidence the urgent need to search for new compounds with antibacterial activity. The adaptations that Antarctic microorganisms have developed, due to the extreme environment that they inhabit, promote them as a potential new source of active compounds for the control of microorganisms causing infections associated with health care. The aim of this study was to evaluate the antibacterial activity of an ethanol extract of the Antarctic bacterium Janthinobacterium sp., strain SMN 33.6, against nosocomial multi-resistant Gram-negative bacteria. Results Inhibitory activity against human Gram-negative bacterial pathogens, with concentrations that varied...
Tipo: Journal article
Palavras-chave: Antarctica; Antimicrobial; Antibiotic resistance; Bacterial pigment.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000100001

Diverse approaches to questions of Biodiversity: German contributions to studies of Marine Benthos around South America and Antartica
Provedor de dados: 72
Autores: Gutt,Julian; Arntz,Wolf E; Balguerias,Eduardo; Brandt,Angelika; Gerdes,Dieter; Gorny,Matthias; Sirenko,Boris.
A look at the latitudinal gradient from North America via South America to Antarctica supports the impression that the ecosystems of this part of the world provide perfect conditions for marine biodiversity studies. Several bilateral or international initiatives with major German contributions have focused on biodiversity questions, especially in South America and Antarctica. At depths &gt; 50 m accessible to shipboard sampling, an oxygen minimum zone (OMZ) prevails off Peru and Chile (except in the extreme south). The macrobenthic biota associated with the OMZ are extremely poor but show a gradient of increasing diversity at great depths and towards the south. In the southern Chilean fjords and channels, habitat heterogeneity is high and differences in...
Tipo: Journal article
Palavras-chave: Marine biodiversity; South America; Antarctica.
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-65382003000200007

Pelagic ostracods (Halocyprididae) of the Brandsfield Strait, Antarctica
Provedor de dados: 13
Autores: Drapun, I. E.
Results of the study of pelagic ostracods (Halocyprididae) from the western Bransfield Strait are discussed. The data were obtained using zooplankton samples collected in March 2002 during the 7th Ukrainian Antarctic expedition. Maximum sampling depths varied from 200 to 1000 m. Eight halocyprid species were found. Three species were dominant throughout the entire sampling depth: Metaconchoecia isocheira (in the layers 0 – 500 and &gt;500 m it contributed 44 and 31 % respectively to the halocyprid population), Alacia belgicae (28 and 23 %), and Alacia hettacra (24 and 21 %). The fourth species, Boroecia antipoda, was dominant &gt;500 m (21 %). The other species found were Metaconchoecia skogsbergi, Proceroecia brachyaskos, Disconchoecia aff. elegans and...
Tipo: Journal Contribution
Palavras-chave: Pelagic ostracods; Halocyprididae; Quantitative distribution; Age structure; Bransfield Strait; Antarctica; Пелагические остракоды; Halocyprididae; Количественное распределение; Возрастная структура; Пролив Брансфилда; Антарктика Quantitative distribution.
Ano: 2006
URL: http://repository.ibss.org.ua/dspace/handle/99011/273

Antropogenic radionuclides in plants, animals and their environments in Antarctica
Provedor de dados: 13
Autores: Giuliani, S.; Triulz, C.; Vaghi, M.
In the framework of the Italian National Research Program in Antarctica (PNRA), the Laboratory of Radioecology of the University of Parma developed from 1987 several researches on terrestrial and marine samples. At first the prin-cipal aim was the study of 90Sr, 137Cs, 238Pu, 239+240Pu and 241Am concentrations in samples of soil, ice, seawater and biota collected near the Italian Antarctic Base (Ross Sea, Terra Nova Bay).
Tipo: Journal Contribution
Palavras-chave: Antarctica; Pollution; 137Cs; 239+240Pu; 238Pu and 241Am; Антарктика; Загрязнение Pollution Pollution http://aims.fao.org/aos/agrovoc/c_6077.
Ano: 2003
URL: http://repository.ibss.org.ua/dspace/handle/99011/39

Cephalopoda as prey of juvenile Southern elephant seals at Isla 25 de Mayo/King George, South Shetland Islands
Provedor de dados: 76
Autores: Burdman,Luciana; Daneri,Gustavo A.; Negrete,Javier; Mennucci,Jorge A.; Marquez,Maria E. I.
The aim of the present study was to enhance the knowledge of the feeding habits of the juvenile component of the population of Southern elephant seals [Mirounga leonina (Linnaeus, 1758)] from Isla 25 de Mayo, South Shetland Islands, age class whose diet information is scarce. A total of 60 individuals were stomach lavaged in the spring - summer seasons of three consecutive years (2003, 2004 and 2005) of which 53.3 % (n = 32) presented food remnants. The Antarctic glacial squid Psychroteuthis glacialis Thiele, 1921 was the dominant prey taxon in terms of frequency of occurrence (68.7%), numerical abundance (60.1%) and biomass (51.5%), contributing 84.1% to the total relative importance index. Other squid prey species of importance were Slosarczykovia...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Mirounga; Diet; Antarctica.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0073-47212015000100012

Global biogeography of SAR11 marine bacteria
Provedor de dados: 5
Autores: Brown, Mark V.; Lauro, Federico M.; Demaere, Matthew Z.; Muir, Les; Wilkins, David; Thomas, Torsten; Riddle, Martin J.; Fuhrman, Jed A.; Andrews-pfannkoch, Cynthia; Hoffman, Jeffrey M.; Mcquaid, Jeffrey B.; Allen, Andrew; Rintoul, Stephen R.; Cavicchioli, Ricardo.
The ubiquitous SAR11 bacterial clade is the most abundant type of organism in the world’s oceans, but the reasons for its success are not fully elucidated. We analysed 128 surface marine metagenomes, including 37 new Antarctic metagenomes. The large size of the data set enabled internal transcribed spacer (ITS) regions to be obtained from the Southern polar region, enabling the first global characterization of the distribution of SAR11, from waters spanning temperatures −2 to 30°C. Our data show a stable co-occurrence of phylotypes within both ‘tropical’ (&gt;20°C) and ‘polar’ (&lt;10°C) biomes, highlighting ecological niche differentiation between major SAR11 subgroups. All phylotypes display transitions in abundance that are strongly correlated with...
Tipo: Text
Palavras-chave: Adaptive radiation; Antarctica; Metagenome; Pelagibacter; Phylotype distribution.
Ano: 2012
URL: https://archimer.ifremer.fr/doc/00140/25132/23242.pdf

Immune response of the Antarctic sea urchin Sterechinus neumayeri: cellular, molecular and physiological approach
Provedor de dados: 5
Autores: Gonzalez-aravena, Marcelo; Perez-troncoso, Carolina; Urtubia, Rocio; Branco, Paola; Machado Cunha Da Silva, Jose Roberto; Mercado, Luis; De Lorgeril, Julien; Bethke, Jorn; Paschke, Kurt.
In the Antarctic marine environment, the water temperature is usually between 2 and - 1.9 degrees C. Consequently, some Antarctic species have lost the capacity to adapt to sudden changes in temperature. The study of the immune response in Antarctic sea urchin (Sterechinus neumayeri) could help us understand the future impacts of global warming on endemic animals in the Antarctic Peninsula. In this study, the Antarctic sea urchins were challenged with lipopolysaccharides and Vibrio alginolitycus. The cellular response was evaluated by the number of coelomocytes and phagocytosis. A significant increase was observed in red sphere cells and total coelomocytes in animals exposed to LPS. A significant rise in phagocytosis in animals stimulated by LPS was also...
Tipo: Text
Palavras-chave: Sea urchin; Antarctica; Sterechinus neumayeri; Coelomocytes; Phagocytosis; Gene expression.
Ano: 2015
URL: http://archimer.ifremer.fr/doc/00439/55012/56441.pdf

Interannual variability of dimethylsulfide in air and seawater and its atmospheric oxidation by-products (methanesulfonate and sulfate) at Dumont d'Urville, coastal Antarctica (1999-2003)
Provedor de dados: 5
Autores: Preunkert, Susanne; Legrand, Michel; Jourdain, Bruno; Moulin, Cyril; Belviso, Sauveur; Kasamatsu, Nobue; Fukuchi, Mitsuo; Hirawake, Toru.
A multiple year-round study of atmospheric dimethyl sulfide (DMS) (from December 1998 to April 2003) as well as sulfur-derived aerosols (methanesulfonic acid (MSA) and non-sea-salt sulfate) (from March 1991 to February 2003) was conducted at Dumont d'Urville, coastal Antarctica. The three sulfur-derived species exhibit a seasonal cycle characterized by maxima in midsummer (January). Whereas the interannual variability of winter levels remains low, a strong interannual variability is shown in summer, particularly for DMS and MSA, and to a lesser extent for non-sea-salt sulfate. Over the 1998-2003 time period, January 2002 stands out with high values for all sulfur species. These interannual variabilities of atmospheric summer levels are examined in the...
Tipo: Text
Palavras-chave: Sulfur cycle; Antarctica; Dimethylsulfure.
Ano: 2007
URL: https://archimer.ifremer.fr/doc/00236/34728/33177.pdf

Holocene long- and short-term climate changes off Adelie Land, East Antarctica
Provedor de dados: 5
Autores: Crosta, X.; Debret, M.; Denis, D.; Courty, M. A.; Ther, O.
Diatom data from a marine sediment core give insight on Holocene changes in sea- surface conditions and climate at high southern latitudes off Adelie Land, East Antarctica. The early to mid- Holocene was warmer than the late Holocene with a transition at similar to 4000 calendar years B. P. Sea ice was less present and spring- summer growing season was greater during the warm period relative to the cold one, thus limiting sea ice diatom production and favoring more open ocean diatom to develop. The long- term Holocene climatic evolution in East Antarctica is explained by a combination of a delayed response to local seasonal insolation changes coupled to the long memory of the Southern Ocean. Abrupt variations of the diatom relative abundances, indicating...
Tipo: Text
Palavras-chave: Antarctica; Sea ice; Holocene; Insolation; Thermohaline circulation.
Ano: 2007
URL: https://archimer.ifremer.fr/doc/00235/34642/33044.pdf

Large icebergs characteristics from altimeter waveforms analysis
Provedor de dados: 5
Autores: Tournadre, Jean; Bouhier, Nicolas; Girard-ardhuin, Fanny; Remy, F.
Large uncertainties exist on the volume of ice transported by the Southern Ocean large icebergs, a key parameter for climate studies, because of the paucity of information, especially on iceberg thickness. Using icebergs tracks from the National Ice Center (NIC) and Brigham Young University (BYU) databases to select altimeter data over icebergs and a method of analysis of altimeter waveforms, a database of 5366 icebergs freeboard elevation, length, and backscatter covering the 2002–2012 period has been created. The database is analyzed in terms of distributions of freeboard, length, and backscatter showing differences as a function of the iceberg's quadrant of origin. The database allows to analyze the temporal evolution of icebergs and to estimate a melt...
Tipo: Text
Palavras-chave: Iceberg; Antarctica; Altimetry; Ice balance.
Ano: 2015
URL: http://archimer.ifremer.fr/doc/00256/36719/35333.pdf

Effects of incubation temperature on growth and production of exopolysaccharides by an Antarctic sea ice bacterium grown in batch culture
Provedor de dados: 5
Autores: Nichols, Carol; Bowman, John; Guezennec, Jean.
The sea ice microbial community plays a key role in the productivity of the Southern Ocean. Exopolysaccharide (EPS) is a major component of the exopolymer secreted by many marine bacteria to enhance survival and is abundant in sea ice brine channels, but little is known about its function there. This study investigated the effects of temperature on EPS production in batch culture by CAM025, a marine bacterium isolated from sea ice sampled from the Southern Ocean. Previous studies have shown that CAM025 is a member of the genus Pseudoalteromonas and therefore belongs to a group found to be abundant in sea ice by culture-dependent and -independent techniques. Batch cultures were grown at -2 degrees C, 10 degrees C, and 20 degrees C, and cell number, optical...
Tipo: Text
Palavras-chave: EPS yield; Psychrotolerant; Sea ice; Marine bacteria; Antarctica; Exopolymer; Exopolysaccharides.
Ano: 2005
URL: http://archimer.ifremer.fr/doc/2005/publication-625.pdf

Antarctic icebergs: A significant natural ocean sound source in the Southern Hemisphere
Provedor de dados: 5
Autores: Matsumoto, Haru; Bohnenstiehl, Delwayne R.; Tournadre, Jean; Dziak, Robert P.; Haxel, Joseph H.; Lau, T. -k. A.; Fowler, Matt; Salo, Sigrid A.
In late 2007, two massive icebergs, C19a and B15a, drifted into open water and slowly disintegrated in the southernmost Pacific Ocean. Archived acoustic records show that the high-intensity underwater sounds accompanying this breakup increased ocean noise levels at mid-to-equatorial latitudes over a period of ∼1.5 years. More typically, seasonal variations in ocean noise, which are characterized by austral summer-highs and winter-lows, appear to be modulated by the annual cycle of Antarctic iceberg drift and subsequent disintegration. This seasonal pattern is observed in all three Oceans of the Southern Hemisphere. The life cycle of Antarctic icebergs affects not only marine ecosystem but also the sound environment in far-reaching areas and must be...
Tipo: Text
Palavras-chave: Antarctica; Iceberg; Ocean noise; Seasonality; Trend.
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00205/31613/30035.pdf

Tide-induced microseismicity in the Mertz glacier grounding area, East Antarctica
Provedor de dados: 5
Autores: Barruol, Guilhem; Cordier, Emmanuel; Bascou, Jerome; Fontaine, Fabrice R.; Legresy, Benoit; Lescarmontier, Lydie.
The deployment of a seismic network along the Adelie and George V coasts in East Antarctica during the period 2009-2012 provides the opportunity to monitor cryoseismic activity and to obtain new insights on the relationship between tidal cycles and coastal glacier dynamics. Here we focus on records from a seismometer located on a rocky outcrop in the vicinity of the grounding line of the 35 km broad Mertz glacier, a major outflow of this region. We detect numerous icequakes (50,000 events within 10 months and up to 100 events/h) and demonstrate their clear tidal modulation. We suggest that they result from ice friction and fracturing around the rocky peak and from the glacier flexure in response to the falling and rising tides at its grounding area. We...
Tipo: Text
Palavras-chave: Icequakes; Mertz glacier; Tide; Antarctica; Cryoseismology; Adélie land.
Ano: 2013
URL: https://archimer.ifremer.fr/doc/00244/35567/34098.pdf

Antarctic climate change and the environment
Provedor de dados: 5
Autores: Convey, P.; Bindschadler, R.; Di Prisco, G.; Fahrbach, E.; Gutt, J.; Hodgson, D. A.; Mayewski, P. A.; Summerhayes, C. P.; Turner, J.; ACCE CONSORTIUM.
The Antarctic climate system varies on timescales from orbital, through millennial to sub-annual, and is closely coupled to other parts of the global climate system. We review these variations from the perspective of the geological and glaciological records and the recent historical period from which we have instrumental data (similar to the last 50 years). We consider their consequences for the biosphere, and show how the latest numerical models project changes into the future, taking into account human actions in the form of the release of greenhouse gases and chlorofluorocarbons into the atmosphere. In doing so, we provide an essential Southern Hemisphere companion to the Arctic Climate Impact Assessment.
Tipo: Text
Palavras-chave: Antarctica; Biology; Environmental change; Geology; Glaciology; Southern Ocean.
Ano: 2009
URL: https://archimer.ifremer.fr/doc/00292/40357/82998.pdf

Antarctic Sea Ice Proxies from Marine and Ice Core Archives Suitable for Reconstructing Sea Ice over the past 2000 Years
Provedor de dados: 5
Autores: Thomas, Elizabeh R; Allen, Claire S; Etourneau, Johan; King, Amy Cf; Severi, Mirko; Winton, V. Holly L.; Mueller, Juliane; Crosta, Xavier; Peck, Victoria L.
Dramatic changes in sea ice have been observed in both poles in recent decades. However, the observational period for sea ice is short, and the climate models tasked with predicting future change in sea ice struggle to capture the current Antarctic trends. Paleoclimate archives, from marine sedimentary records and coastal Antarctic ice cores, provide a means of understanding sea ice variability and its drivers over decadal to centennial timescales. In this study, we collate published records of Antarctic sea ice over the past 2000 years (2 ka). We evaluate the current proxies and explore the potential of combining marine and ice core records to produce multi-archive reconstructions. Despite identifying 92 sea ice reconstructions, the spatial and temporal...
Tipo: Text
Palavras-chave: Sea ice; Antarctica; Paleoclimate; Ice cores; Marine sediments.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00595/70709/68916.pdf

High inter‐ and intraspecific niche overlap among three sympatrically breeding, closely‐related seabird species: Generalist foraging as an adaptation to a highly variable environment?
Provedor de dados: 5
Autores: Dehnhard, Nina; Achurch, Helen; Clarke, Judy; Michel, Loic; Southwell, Colin; Sumner, Michael D.; Eens, Marcel; Emmerson, Louise.
1.Ecological niche theory predicts sympatric species to show segregation in their spatio‐temporal habitat utilization or diet as a strategy to avoid competition. Similarly, within species individuals may specialise on specific dietary resources or foraging habitats. Such individual specialisation seems to occur particularly in environments with predictable resource distribution and limited environmental variability. Still little is known about how seasonal environmental variability affects segregation of resources within species and between closely related sympatric species. 2.The aim of the study was to investigate the foraging behaviour of three closely related and sympatrically breeding fulmarine petrels (Antarctic petrels Thalassoica antarctica, cape...
Tipo: Text
Palavras-chave: Antarctica; Biologging; Expectation-Maximization binary Clustering (EMbC); Fulmarine petrel; Generalized additive model (GAM); Kernel distribution; Model cross-validation; Stable isotope analysis.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00509/62056/66218.pdf

Metagenomic sequencing of environmental DNA reveals marine faunal assemblages from the West Antarctic Peninsula
Provedor de dados: 5
Autores: Cowart, Dominique; Murphy, Katherine R.; Cheng, C. -h. Christina.
The West Antarctic Peninsula (WAP) is the fastest warming region in Antarctica where climate impact on the cold-adapted marine ecosystem is already visible. To monitor faunal changes in remote vast bodies of Antarctic waters, efficient and informative tools are essential. High-throughput sequencing of environmental DNA (eDNA) has emerged as one such tool for monitoring biodiversity and ecosystems, as it increases detection sensitivity of taxa, and sampling is often simpler and less costly than traditional collection methods. We collected water samples from four WAP shallow (≤ 300 m) shelf regions, recovered the eDNA therein, and performed metagenomic shotgun sequencing and analyses to determine the effectiveness of this method to assess marine benthic...
Tipo: Text
Palavras-chave: EDNA; Antarctica; Metagenomics; King crabs; Benthic invertebrates.
Ano: 2018
URL: http://archimer.ifremer.fr/doc/00413/52490/53278.pdf

Holocene variation in the Antarctic coastal food web: linking δD and δC13 in snow petrel diet and marine sediments
Provedor de dados: 5
Autores: Ainley, Dg; Hobson, Ka; Crosta, X; Rau, Gh; Wassenaar, Li; Augustinus, Pc.
Here we present first time evidence for concordant variation in the isotopic signature at both the base and the upper levels of the Antarctic coastal food web during the Holocene. Laminae in sub-fossil deposits of snow petrel Pagodroina nivea stomach oil, known as mumiyo, were collected from nest-sites in the Bunger Hills, East Antarctica. Mumiyo layers were sub-sampled, radiocarbondated, and analyzed for delta C-13 and delta D. The obtained values were compared to isotopic variability among layers of an ocean sediment core collected, and similarly dated, in nearby Dumont D'Urville Trough. Overlapping records extended from about 10 160 to 526 calendar years before present (cal yr BP). Mumiyo delta D values remained relatively constant throughout the...
Tipo: Text
Palavras-chave: Antarctica; Holocene climate change; Food webs; Isotopic analysis; Mumiyo; Pagodroma nivea; Sediment cores; Snow petrel.
Ano: 2006
URL: https://archimer.ifremer.fr/doc/00496/60808/64708.pdf

Retreat history of the East Antarctic Ice Sheet since the Last Glacial Maximum
Provedor de dados: 5
Autores: Mackintosh, Andrew N.; Verleyen, Elie; O'Brien, Philip E.; White, Duanne A.; Jones, R. Selwyn; Mckay, Robert; Dunbar, Robert; Gore, Damian B.; Fink, David; Post, Alexandra L.; Miura, Hideki; Leventer, Amy; Goodwin, Ian; Hodgson, Dominic A.; Lilly, Katherine; Crosta, Xavier; Golledge, Nicholas R.; Wagner, Bernd; Berg, Sonja; Van Ommen, Tas; Zwartz, Dan; Roberts, Stephen J.; Vyverman, Wim; Masse, Guillaume.
The East Antarctic Ice Sheet (EAIS) is the largest continental ice mass on Earth, and documenting its evolution since the Last Glacial Maximum (LGM) is important for understanding its present-day and future behaviour. As part of a community effort, we review geological evidence from East Antarctica that constrains the ice sheet history throughout this period (similar to 30,000 years ago to present). This includes terrestrial cosmogenic nuclide dates from previously glaciated regions, C-14 chronologies from glacial and post-glacial deposits onshore and on the continental shelf, and ice sheet thickness changes inferred from ice cores and continental-scale ice sheet models. We also include new C-14 dates from the George V Land Terre Adelie Coast shelf. We...
Tipo: Text
Palavras-chave: Antarctica; Last Glacial Maximum; Ice sheet; Sea level rise.
Ano: 2014
URL: https://archimer.ifremer.fr/doc/00290/40085/39171.pdf

HSP70 from the Antarctic sea urchin Sterechinus neumayeri: molecular characterization and expression in response to heat stress
Provedor de dados: 5
Autores: Gonzalez-aravena, Marcelo; Calfio, Camila; Mercado, Luis; Morales-lange, Byron; Bethke, Jorn; De Lorgeril, Julien; Cardenas, Cesar A.
Background Heat stress proteins are implicated in stabilizing and refolding denatured proteins in vertebrates and invertebrates. Members of the Hsp70 gene family comprise the cognate heat shock protein (Hsc70) and inducible heat shock protein (Hsp70). However, the cDNA sequence and the expression of Hsp70 in the Antarctic sea urchin are unknown. Methods We amplified and cloned a transcript sequence of 1991 bp from the Antarctic sea urchin Sterechinus neumayeri, experimentally exposed to heat stress (5  and 10 °C for 1, 24 and 48 h). RACE-PCR and qPCR were employed to determine Hsp70 gene expression, while western blot and ELISA methods were used to determine protein expression. Results The sequence obtained from S. neumayeri showed high identity with Hsp70...
Tipo: Text
Palavras-chave: Hsp70; Coelomocytes; Antarctica; Echinoderms; Climate change.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00435/54619/56019.pdf

Antarctic palaeo-ice streams
Provedor de dados: 5
Autores: Livingstone, Stephen J.; Cofaigh, Colm O.; Stokes, Chris R.; Hillenbrand, Claus-dieter; Vieli, Andreas; Jamieson, Stewart S. R.
We review the geomorphological, sedimentological and chronological evidence for palaeo-ice streams on the continental shelf of Antarctica and use this information to investigate basal conditions and processes, and to identify factors controlling grounding-line retreat. A comprehensive circum-Antarctic inventory of known palaeo-ice streams, their basal characteristics and minimum ages for their retreat following the Last Glacial Maximum (LGM) is also provided. Antarctic palaeo-ice streams are identified by a set of diagnostic landforms that, nonetheless, display considerable spatial variability due to the influence of substrate, flow velocity and subglacial processes. During the LGM, palaeo-ice streams extended, via bathymetric troughs, to the shelf edge of...
Tipo: Text
Palavras-chave: Antarctica; Ice stream; Grounding-line retreat; Glacial geomorphology; Deglacial history.
Ano: 2012
URL: https://archimer.ifremer.fr/doc/00266/37684/82771.pdf

Circulation and water mass transports on the East Antarctic shelf in the Mertz Glacier region
Provedor de dados: 5
Autores: Martin, Antoine; Houssais, Marie-noelle; Le Goff, Herve; Marec, Claudie; Dausse, Denis.
The East Antarctic shelf off Adélie-George V Land is known to be an important region for Dense Shelf Water (DSW) formation as a result of intense sea ice production in the Mertz Glacier Polynya during the winter season. It is also a region where the warm modified Circumpolar Deep Water (mCDW) penetrates onto the shelf during the summer. Using hydrographic observations from a summer survey in 2008 we implement a box inverse model to propose a comprehensive view of the steady state circulation on this shelf in summer. Additional information from mooring observations collected on the depression slope is used to provide context to the retrieved circulation scheme. Over the depression slope, the summer baroclinic structure of the currents is found to contrast...
Tipo: Text
Palavras-chave: Antarctica; Continental shelf; Modified Circumpolar Deep Water; Heat transport; Freshwater transport; Adelie Georges V Land.
Ano: 2017
URL: http://archimer.ifremer.fr/doc/00386/49766/50302.pdf

Integrated assessment of the spatial distribution and structural dynamics of deep benthic marine communities
Provedor de dados: 5
Autores: Jansen, Jan; Dunstan, Piers K.; Hill, Nicole A.; Koubbi, Philippe; Melbourne‐thomas, Jessica; Causse, Romain; Johnson, Craig R.
Characterising the spatial distribution and variation of species communities and validating these characteristics with data from the field are key elements for an ecosystem‐based approach to management. However, models of species distributions that yield community structure are usually not linked to models of community dynamics, constraining understanding and management of the ecosystem, particularly in data‐poor regions. Here we use a qualitative network model to predict changes in Antarctic benthic community structure between major marine habitats characterised largely by seafloor depth and slope, and use multivariate mixture models of species distributions to validate the community dynamics. Further, we then assess how future increases in primary...
Tipo: Text
Palavras-chave: Deep‐sea; Ecosystem structure; Ecosystem dynamic; Southern Ocean; Antarctica; Continental shelf; Upper slope; Species archetype model; Qualitative network model; Spatial model.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00599/71143/69460.pdf

High-resolution estimates of Southwest Indian Ridge plate motions, 20 Ma to present
Provedor de dados: 5
Autores: Demets, C.; Merkouriev, S.; Sauter, D.
We present the first estimates of Southwest Indian Ridge (SWIR) plate motions at high temporal resolution during the Quaternary and Neogene based on nearly 5000 crossings of 21 magnetic reversals out to C6no (19.72 Ma) and the digitized traces of 17 fracture zones and transform faults. Our reconstructions of this slow-spreading mid-ocean ridge reveal several unexpected results with notable implications for regional and global plate reconstructions since 20 Ma. Extrapolations of seafloor opening distances to zero-age seafloor based on reconstructions of reversals C1n (0.78 Ma) through C3n.4 (5.2 Ma) reveal evidence for surprisingly large outward displacement of 5 ± 1 km west of 32°E, where motion between the Nubia and Antarctic plates occurs, but 2 ± 1 km...
Tipo: Text
Palavras-chave: Plate motions; Africa; Antarctica.
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00296/40684/39674.pdf

Advanced insights into magmatism and volcanism of the Mozambique Ridge and Mozambique Basin in the view of new potential field data
Provedor de dados: 5
Autores: Koenig, Matthias; Jokat, Wilfried.
P&gt;A new plate tectonic model is presented which describes the emplacement of the Mozambique Ridge off southeast Africa as the result of long lasting volcanic activity (140-122 Ma) during the initial opening between Africa and Antarctica. Thus, an oceanic origin for the Mozambique Ridge is proposed. This model is based on a new and systematic high resolution magnetic anomaly data set acquired across the Mozambique Ridge and throughout the Mozambique Basin. Data from the Mozambique Basin allow the identification of Mesozoic magnetic anomalies from M0r to M26 (124.61-155.3 Ma) with previously unmatched accuracy. Small-scale fracture zones are recognized by offsets of magnetic anomalies in the westernmost part of the basin. Additionally, a bend in the major...
Tipo: Text
Palavras-chave: Magnetic anomalies: modelling and interpretation; Marine magnetics and palaeomagnetics; Oceanic plateaus and microcontinents; Large igneous provinces; Africa; Antarctica.
Ano: 2010
URL: https://archimer.ifremer.fr/doc/00231/34261/32626.pdf

Chemical characterization of exopolysaccharides from Antarctic marine bacteria
Provedor de dados: 5
Autores: Nichols, Carol; Lardiere, Sandrine; Bowman, John; Nichols, Peter; Gibson, John; Guezennec, Jean.
Exopolysaccharides (EPS) may have an important role in the Antarctic marine environment, possibly acting as ligands for trace metal nutrients such as iron or providing cryoprotection for growth at low temperature and high salinity. Ten bacterial strains, isolated from Southern Ocean particulate material or from sea ice, were characterized. Whole cell fatty acid profiles and 16S rRNA gene sequences showed that the isolates included representatives of the genera Pseudoalteromonas, Shewanella, Polaribacter, and Flavobacterium as well as one strain, which constituted a new bacterial genus in the family Flavobacteriaceae. The isolates are, therefore, members of the "Gammaproteobacteria" and Cytophaga-Flexibacter-Bacteroides, the taxonomic groups that have been...
Tipo: Text
Palavras-chave: Marine particulates; Sea ice; Marine bacteria; Antarctica; Exopolysaccharides.
Ano: 2005
URL: http://archimer.ifremer.fr/doc/2005/publication-623.pdf

Iceberg detection in open water by altimeter waveform analysis
Provedor de dados: 5
Autores: Tournadre, Jean; Whitmer, K; Ardhuin, Fanny.
Small icebergs (edge lengths &lt;1 km) are difficult to detect and track. In a recently published study, it was demonstrated that small targets (ships, islets,...) emerging from the sea can be detected by the analysis of high-rate altimeter waveforms. The analysis of Jason altimeter data revealed that small icebergs also have a detectable signature in the thermal noise part of the altimeter waveforms for open water. These signatures are very similar to that of transponders and are almost deterministic. An automated method based on the detection of parabolic shapes in the thermal part of the waveforms by analysis of the convolution product with a filter has been developed and applied to 1 year of Jason high-rate waveform data. In addition, the minimum...
Tipo: Text
Palavras-chave: Antarctica; Iceberg; Altimeter waveform.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-4530.pdf

Etude de l'impact des icebergs Antarctiques sur l'Océan Austral
Provedor de dados: 5
Autores: Bouhier, Nicolas.
The Antarctic polar ice cap constrains a freshwater flaux into the Austral Ocean through two equally important pathways : a localized and immediate injection through the melting of ice-shelves bases, and a delayed offshore injection through the calving and subsequent melt of icebergs. Some studies reckon that melting icebergs have the capacity to alter the hydrological and biogeo-chemical characteristics of the water column. The numerical models trying to evaluate this impact have shown contrasting results. Yet, they might suffer from a poor representation of the icebergs, namely due to our limited knowledge on both the spatial and size distributions of the icebergs, or even the processes involved in their mass loss. A new method using satellite altimetry...
Tipo: Text
Palavras-chave: Ntarctique; Calotte polaire; Plate-forme glaciaire; Océan austral; Flux d’eau douce; Télédétection; Banquise; Fonte; Fracturation; Distribution de taille; Antarctica; Ice cap; Ice shelf; Southern Ocean; Iceberg; Freshwater flux; Remote sensing; Sea ice; Melting; Fragmentation; Fracturing; Size distribution.
Ano: 2017
URL: https://archimer.ifremer.fr/doc/00497/60905/64253.pdf

Circumpolar dataset of sequenced specimens of Promachocrinus kerguelensis (Echinodermata, Crinoidea)
Provedor de dados: 5
Autores: Hemery, Lenaig G.; Ameziane, Nadia; Eleaume, Marc.
This circumpolar dataset of the comatulid (Echinodermata: Crinoidea) Promachocrinus kerguelensis (Carpenter, 1888) from the Southern Ocean, documents biodiversity associated with the specimens sequenced in Hemery et al. (2012). The aim of Hemery et al. (2012) paper was to use phylogeographic and phylogenetic tools to assess the genetic diversity, demographic history and evolutionary relationships of this very common and abundant comatulid, in the context of the glacial history of the Antarctic and Sub-Antarctic shelves (Thatje et al. 2005, 2008). Over one thousand three hundred specimens (1307) used in this study were collected during seventeen cruises from 1996 to 2010, in eight regions of the Southern Ocean: Kerguelen Plateau, Davis Sea, Dumont d'Urville...
Tipo: Text
Palavras-chave: Antarctica; Crinoidea; Cytochrome Oxydase subunit I; Echinodermata; Phylogeography; Promachocrinus; Southern Ocean; Sub-Antarctic.
Ano: 2013
URL: https://archimer.ifremer.fr/doc/00296/40758/39749.pdf

Ice-age variability from the Vostok deuterium and deuterium excess records
Provedor de dados: 5
Autores: Yiou, P; Vimeux, F; Jouzel, J.
The four climatic cycles obtained from the Vostok ice core offer a unique opportunity to study the high-frequency paleoclimatic variability, i.e., on time scales smaller than 15 kyr. We focused our study on the deuterium (deltaD) and deuterium excess (d) records, which are proxies for local temperature and remote evaporation source temperature and hence give us access to spatial climatic variations. Spectral analyses of paleoclimatic records have shown that the last glacial period (110-15 kyr before present) is characterized by large and fast temperature oscillations. Examples of such variations in the Northern Hemisphere are the so-called Dansgaard-Oeschger oscillations and Heinrich events. At Vostok, these oscillations are also imprinted in the ice, with...
Tipo: Text
Palavras-chave: Climate dynamics; Antarctica; Meteorology and Atmospheric Dynamics; Paleoclimatology; Paleoceanography.
Ano: 2001
URL: https://archimer.ifremer.fr/doc/00221/33219/31699.pdf

Cloning and expression analysis of allograft inflammatory factor type 1 in coelomocytes of antarctic sea urchin (Sterechinus neumayeri)
Provedor de dados: 5
Autores: Ovando, Fernanda; Gimpel, Carla; Cardenas, Constanza; Machado Cunha Da Silva, Jose Roberto; De Lorgeril, Julien; Gonzalez, Marcelo.
We have cloned and characterized for the first time an allograft inflammatory factor 1 (Sn-AIF-1) from the Antarctic sea urchin. We report the cloning of Sn-AIF-1 cDNA and the characterization of its expression in coelomocytes after a bacterial challenge. The cDNA Sn-AIF-1 has a size of 608 bp and encodes a polypeptide of 151 aa. The deduced amino acid sequence has a putative size of 17.430 Da, an isoelectric point of 4.92, and shows 2 elongation factor handlike motifs that normally bind calcium ions. BLAST analysis revealed close matches with other known AIF-1. The deduced amino acid sequence of Sn-AIF-1 showed high homology with AIF-1 in vertebrates such as fish, mice, and humans; and in the case of invertebrates, the major degree of identity (55%) was...
Tipo: Text
Palavras-chave: Antarctica; Sea urchin; Sterechinus neumayeri; Coelomocytes; Gene expression; AIF-1.
Ano: 2012
URL: http://archimer.ifremer.fr/doc/00098/20955/18572.pdf

Magotanais, a new genus of Tanaidacea (Tanaidomorpha, Crustacea) from the Weddell Sea, Antarctica
Provedor de dados: 16
Autores: Guerrero-Kommritz, Jürgen; Blazewicz-Paszkowycz, Magdalena.
A new species and genus of Tanaidacea is described from the deep sea off Antarctica. Magotanais n. gen. resembles the genus Tanaella Norman &amp; Stebbing, 1886 in its habitus. The biramous uropod, the form of the pars molaris, and the absence of coxae on the pereopods distinguishes it clearly from species belonging to the genus Tanaella. This genus is conformed by one species Magotanais pruinosus n. sp.
Tipo: Article / Letter to the editor
Palavras-chave: Tanaidacea; Colletteidae; Magotanais pruinosus n. gen. n. sp.; Weddell sea; Antarctica; Deep sea.
Ano: 2004
URL: http://www.repository.naturalis.nl/record/504752

Storthyngurinae (Isopoda, Asellota, Munnopsididae) from the Antarctic deep sea with the descriptions of three new species
Provedor de dados: 16
Autores: Malyutina, Marina; Brandt, Angelika.
Storthyngurinae from the deep sea of the West-Atlantic sector of the Antarctic have been studied. The illustrated descriptions of three new species: Storthyngurella andeepae n. sp., Sursumura angulata n. sp., and S. longicauda n. sp. are presented. Moreover, descriptive notes additionally to the original illustrations of the holotypes of Sursumura argentica and S. falcata (George &amp; Menzies, 1968), and a list of species of Sursumura with their distribution as well as a character table of differences between the genera Sursumura and Storthyngurella are presented.
Tipo: Article / Letter to the editor
Palavras-chave: Deep sea; Antarctica; Taxonomy; Munnopsididae; Storthyngurella; Sursumura; New species.
Ano: 2004
URL: http://www.repository.naturalis.nl/record/505091

Clio piatkowskii, a mesopelagic pteropod new to science (Gastropoda, Opisthobranchia)
Provedor de dados: 16
Autores: Spoel, S. van der; Schalk, P.H.; Bleeker, J.
A pteropod species new to science: Clio piatkowskii is described from benthopelagic samples taken in high Antarctic waters of the Weddell Sea. Comparisons with related species are made and its taxonomic place in the genus Clio is discussed.
Tipo: Article / Letter to the editor
Palavras-chave: Gastropoda; Pteropoda; Clio; Taxonomy; Plankton; Antarctica.
Ano: 1992
URL: http://www.repository.naturalis.nl/record/504812

Phylogenetic analysis of the Antarctic genus Oswaldella Stechow, 1919 (Hydrozoa, Leptomedusae, Kirchenpaueriidae)
Provedor de dados: 16
Autores: Peña Cantero, Alvaro L.; Marques, Antonio C.
A cladistic study was carried out on known species of the characteristically Antarctic genus Oswaldella, adopting as outgroups some other genera included in the family Kirchenpaueriidae. The analysis resulted in a cladogram with low CI in which no relationship between genera can be depicted. However, the hypothesis of monophyly of the genus Oswaldella is corroborated, being supported in our cladogram by five synapomorphies (although all are homoplastic with other taxa or reversed within the species of the genus). The basal relationships of the genus are uncertain, but three species groups are distinguishable within Oswaldella: 1) the O. incognita group, 2) the O. antarctica group, and 3) a clade formed by (O. garciacarrascosai, O. elongata ( O. blanconae...
Tipo: Article / Letter to the editor
Palavras-chave: Hydrozoa; Kirchenpaueriidae; Oswaldella; Antarctica; Systematics; Cladistics.
Ano: 1999
URL: http://www.repository.naturalis.nl/record/534328

Octocorallia (Cnidaria: Anthozoa) from the Scotia Arc, South Atlantic Ocean. I. The genus Alcyonium Linnaeus, 1758
Provedor de dados: 16
Autores: Casas, C.; Ramil, F.; Ofwegen, L.P. van.
Three new species of Alcyonium collected by the Spanish Antarctic Expeditions "Antártida 8611" and "Bentart 95" are described and figured: Alcyonium paucilobulatum, A. grandis and A. southgeorgiensis. Another two species, A. antarcticum Wright &amp; Studer, 1889, and Alcyonium sollasi Wright &amp; Studer, 1889, were also collected in the same area.
Tipo: Article / Letter to the editor
Palavras-chave: Anthozoa; Octocorallia; Alcyonium; New species; Antarctica; 42.72.
Ano: 1997
URL: http://www.repository.naturalis.nl/record/319078

Frontoserolis abyssalis n. sp. and Serolis arntzi n. sp. (Serolidae, Isopoda) from the Antarctic deep sea
Provedor de dados: 16
Autores: Brandt, Angelika.
A new collection of Serolidae (Crustacea, Malacostraca) from the deep sea of the West-Atlantic part of Antarctica has been studied. Descriptions of the new species Frontoserolis abyssalis n. sp. and Serolis arntzi n. sp. are presented. F. abyssalis n. sp. is very similar to F. acuminata (Sheppard, 1957) and F. aestimabilis (Brandt, 1988), but can easily be distinguished from these by its vestigial eyes and a different ornamentation of head and pleotelson. S. arntzi n. sp. is most similar to S. rugosa, but can be discriminated from this species by the sculpture of the head, the pereonites and the pleotelson.
Tipo: Article / Letter to the editor
Palavras-chave: Taxonomy; New species; Serolidae; Antarctica; Deep sea.
Ano: 2003
URL: http://www.repository.naturalis.nl/record/505110

A new deep-sea isopod from the Weddell Sea, Antarctica: Coperonus pinguis n. sp. (Crustacea, Isopoda, Munnopsidae)
Provedor de dados: 16
Autores: Brandt, Angelika.
A new species of Coperonus, C. pinguis, is described from the Antarctic deep sea. It is the first record of an Antarctic deep-sea species in this genus and the southernmost record of Coperonus.
Tipo: Article / Letter to the editor
Palavras-chave: Taxonomy; Biogeography; Antarctica; Weddell Sea; Deep sea; Coperonus.
Ano: 1992
URL: http://www.repository.naturalis.nl/record/503974

Biodiversidad y distribución temporal de zooplancton gelatinoso en bahía Fildes
Provedor de dados: 20
Autores: Mora, G.
El proyecto “Biodiversidad y distribución temporal de zooplancton gelatinoso en bahía Fildes”, perteneciente al Programa de Apoyo a Tesis en Temas Antárticos, organizado por el INACH, aportará información sobre la fluctuación temporal, de corto plazo, de los principales grupos de zooplancton gelatinoso (medusas, sifonóforos, quetognatos, ctenóforos y salpas) y su asociación con las variables ambientales de temperatura y salinidad.
Tipo: Journal Contribution
Palavras-chave: Zooplankton; Biodiversity; Antarctica.
Ano: 2011
URL: http://hdl.handle.net/1834/4502

Faunistic and anatomical data on the Antarctic Opisthobranchia (Mollusca, Gastropoda) in the collections of the Royal Belgian Institute of Natural Sciences
Provedor de dados: 27
Autores: Troncoso, J.S.; García, F.J.; Backeljau, T.; Urgorri, V.
Five opisthobranch species were collected during the Belgian and Belgian-Dutch Antarctica expeditions to the Riiser-Larsen Sea, the Princess Ragnhild Coast ("Mission Iris") (1960-1967) and Admiralty Bay (King George Island) (1987-1991). These species include &lt;i&gt;Philine alata&lt;/i&gt; Thiele, 1912, &lt;i&gt;Bathyberthella antarctica&lt;/i&gt; Willan &amp; Bertsch, 1987, &lt;i&gt;Notaeolidia gigas&lt;/i&gt; Eliot, 1905, &lt;i&gt;Aegires (Anaegires) albus&lt;/i&gt; Thiele, 1912 and &lt;i&gt;Austrodoris kerguelenensis&lt;/i&gt; Bergh, 1884. This material is deposited in the Royal Belgian Institute of Natural Sciences. The present contribution provides anatomical and faunistic data on this collection and extends the distributional range of several species.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Biological sampling Cruise reports Marine molluscs Museum collections Taxonomy Aegires albus Bathyberthella antarctica Doris kerguelenensis Notaeolidia gigas Philine alata PSW; Antarctica; Dronning Maud Land; Princess Ragn PSW; Antarctica; South Shetland I.; King George I.
Ano: 1996
URL: http://www.vliz.be/imisdocs/publications/303495.pdf

Notes sur les &lt;i&gt;Orchomene&lt;/i&gt; (Amphipodes, Lysianassidae) de l'Ocean Austral: 1. Description d'&lt;i&gt;Orchomene hureaui&lt;/i&gt; n. sp. de Terre Adélie
Provedor de dados: 27
Autores: De Broyer, C.
A new Antarctic lysianassid amphipod, Orchomene hureaui sp.n. from Addlie Land is described and illustrated. The male is unknown. The 2 females were from the stomach of an Adelie penguin. Its epistome is straight and is just in front of the upper lip. The lateral cephalic lobes are rounded and eyes are present. Coxa I is trapezoidal and wide distally, the carpus of gnathopod I shorter than propodite and with no postero-distal lobe, the palm is transverse, slightly convex and deeply toothed. Gnathopod II is subchelate and coxa V has subequal inferior lobes. Uropod III has long setose branches and the telson is divided. The ecology and relations with other Orchomene spp are discussed.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: New species Orchomene hureaui PSE; Antarctica; George V Land; Adelie Land.
Ano: 1973
URL: http://www.vliz.be/imisdocs/publications/295211.pdf

Role of the meiobenthos in Antarctic ecosystems
Provedor de dados: 27
Autores: Vanhove, S.; Wittoeck, J.; Beghyn, M.; Van Gansbeke, D.; Van Kenhove, A.; Coomans, A.; Vincx, M.
To date meiobenthic research remained a big white spot in the systematic-ecological work on Antarctic zoobenthos. Therefore the relative importance of the meiofauna (organisms within the size range of 38-1000µm) in the Antarctic benthic community has been assessed by a combined field ecology and experimental approach. This was done in two contrasting conditions, e.g. the deep sea and low subtidal, where as to the depth of the water column the benthic characteristics were, respectively, indirectly or directly related to primary production. Deep-sea samples were collected at Kapp Norvegia and Halley Bay (Weddell Sea) during the EPOS-leg 3-campaign (summer 1989) with the RV Polarstern at depths between 200 and 2000 m. Samples for the ecological-experimental...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Ecosystems Meiobenthos PS; Antarctic Ocean PS; Antarctica.
Ano: 1997
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=8938

Remarques sur les Polychètes Serpulidae antarctiques &lt;i&gt;Vermiliopsis notialis&lt;/i&gt;, Monro, 1930 et &lt;i&gt;Vermiliopsis glacialis&lt;/i&gt; Monro, 1930
Provedor de dados: 27
Autores: Zibrowius, H.
&lt;i&gt;Vermiliopsis glacialis&lt;/i&gt; (Polychaeta Serpulidae) is redescribed on samples of the Antarctic expedition of the &lt;i&gt;Belgica&lt;/i&gt; (1897-1899) and its affinities are discussed. This material had erroneously been determined by Fauvel (1936) as &lt;i&gt;Vermiliopsis notialis&lt;/i&gt;. The distribution of these two Antarctic species is summarized.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Serpulidae Vermiliopsis glacialis Vermiliopsis notialis PS; Antarctica.
Ano: 1968
URL: http://www.vliz.be/imisdocs/publications/294754.pdf

Expéditions antarctiques belges 1959-1960. Bryozaires
Provedor de dados: 27
Autores: Redier, L.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bryozoa PS; Antarctica.
Ano: 1965
URL: http://www.vliz.be/imisdocs/publications/294263.pdf

Expéditions antarctiques belges. Poissons récoltés par l'expédition d'été 1967
Provedor de dados: 27
Autores: Gosse, J.-P.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Pisces [Fish] PS; Antarctica.
Ano: 1968
URL: http://www.vliz.be/imisdocs/publications/294755.pdf

Pycnogonides provenant de la base antarctique belge
Provedor de dados: 27
Autores: Stock, J.H.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Pycnogonidae PS; Antarctica.
Ano: 1965
URL: http://www.vliz.be/imisdocs/publications/294262.pdf

Expéditions antarctiques Belgo-Néerlandaise. Polychètes
Provedor de dados: 27
Autores: Anichini, C.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Polychaeta [Bristle worms] PS; Antarctica.
Ano: 1967
URL: http://www.vliz.be/imisdocs/publications/294741.pdf

Expéditions antarctiques belges. Mission Iris-1960 C.N.R.P.B. Rapport de la section océanographique
Provedor de dados: 27
Autores: Capart, J.-J.; Closset, F.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Expeditions PS; Antarctica.
Ano: 1964
URL: http://www.vliz.be/imisdocs/publications/294268.pdf

Expéditions antarctiques belges 1964-1965. Bryozoaires (suite)
Provedor de dados: 27
Autores: Redier, L.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bryozoa PS; Antarctica.
Ano: 1966
URL: http://www.vliz.be/imisdocs/publications/289070.pdf

Antarctic Tourists: A Case Study of Their Evaluation of Antarctic Wildlife and Environmental Issues
Provedor de dados: 31
Autores: Tisdell,   Clement A.; Wilson,   Clevo; Kriwoken,   Lorne.
Reports the results of surveys of Antarctic cruise ship passengers on the ‘Akademik Ioffe’ who undertook their Antarctic journey in January 2003.  The prime purposes of the surveys were to determine the socio-economic profile of these travellers, evaluate the importance of Antarctic wildlife for their travel, their attitude to Antarctic wildlife conservation as well as environmental issues involving Antarctica, both prior to their tourist visit to Antarctica and following it.  This paper reports on the socio-economic profile of respondents, their willingness to pay for their Antarctic trip, and their knowledge of Antarctica.  The comparative importance of Antarctic wildlife as a factor motivating respondents to undertake their journey is assessed and the...
Tipo: Working or Discussion Paper
Palavras-chave: Antarctic wildlife conservation; Environmental issues; Willingness to pay; Antarctica; Environmental Economics and Policy.
Ano: 2004
URL: http://purl.umn.edu/48980

Antarctic Tourists, Wildlife and the Environment: Attractions and Reactions to Antarctica
Provedor de dados: 31
Autores: Tisdell,   Clement A.; Wilson,   Clevo.
Provides background on the development and nature of Antarctic tourism and associated environmental issues, as well as agreements and regulations affecting environmental management in Antarctica.  Following an outline of the survey methodology and provision of information on the socioeconomic profiles of the respondents, results of a survey of Antarctic tourists on the Russian registered ship the ‘Akademik Ioffe’ are reported.  The importance of Antarctic wildlife as an attraction for these Antarctic tourists is then given particular attention.  The study considers amongst other things how important Antarctic wildlife was in convincing these tourists to undertake their trip to Antarctica, the importance to the tourists of seeing different species of...
Tipo: Working or Discussion Paper
Palavras-chave: Antarctica; Tourism; Wildlife; Antarctic Treaty; Madrid Protocol; Environmental protection.; Environmental Economics and Policy.
Ano: 2004
URL: http://purl.umn.edu/51295

Antarctic tourism: Environmental concerns and the importance of Antarctica's natural attractions for tourists
Provedor de dados: 31
Autores: Tisdell,   Clement A.
This article provides general background on the development of tourism in Antarctica and environmental concerns raised by it. However, the major part of it reports on and interprets the results from a survey of tourists visiting Antarctica on a cruise ship. Particular attention is given to the socioeconomic profiles of these tourists, their stated level of knowledge of Antarctica before and after their visit, the relative importance to these visitors of seeing different species of Antarctic wildlife and whether or not the opportunity of seeing Antarctic wildlife was of critical importance for their decision to visit Antarctica. The relative valuation by the sampled tourist of features of their Antarctic cruise is explored along with changes in their...
Tipo: Working or Discussion Paper
Palavras-chave: Antarctica; Antarctica’s natural attractions; Cruise ships in Antarctica; Environmental conservation in Antarctica; Tourism in Antarctica; Wildlife conservation in Antarctica.; Consumer/Household Economics; Environmental Economics and Policy; L83; Q26; Q57.
Ano: 2010
URL: http://purl.umn.edu/97469

Enzyme activities of phytoplankton in the South Shetland Islands (Antarctica) in relation to nutrients and primary production
Provedor de dados: 97
Autores: IRIARTE,JOSÉ L; GONZÁLEZ,RODRIGO R; QUIÑONES,RENATO A; KANG,SUNG-HO; SHIM,JAE H; VALENZUELA,CYNTHIA P.
Given the potential significance of enzyme activities as a link between internal metabolic pathways and environmental nutrients, we investigated the relationships of nitrate reductase (NR) and alkaline phosphatase (AP) with primary production and inorganic nutrients in South Shetland Islands, Antarctica. Enzymatic activities of the phytoplankton (0.7-210 µm), primary productivity, autotrophic biomass and inorganic nutrients were studied in the upper 100 m depth at nine stations during a cruise in the northwestern area of South Shetland Islands (Antarctica), during late austral spring (December 2000). NR activities fluctuated between 0 and 42.8 nmol L-1 h-1 (mean = 10.08 nmol L-1 h-1, SD = 10.42 nmol L-1 h-1), AP activities between 0.81 and 5.67 nmol L-1...
Tipo: Journal article
Palavras-chave: Nitrate reductase; Alkaline phosphatase; Primary productivity; Chlorophyll; Antarctica.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2006000400009

Stress tolerance of Antarctic macroalgae in the early life stages
Provedor de dados: 97
Autores: Navarro,Nelso P.; Huovinen,Pirjo; Gomez,Ivan.
BACKGROUND: Early life stages of macroalgae, especially from polar species, can be highly vulnerable to physical stressors, leading to important consequences for the fate of the whole population in scenarios of changing environmental variability. In the present study, tolerance to UV and temperature stress, as measured by rapid adjustment of photochemistry, Fv/Fm, and photosynthetic characteristics based on P-E curves (ETRmax, &amp;#945; and Ek), was assessed in the early life stages of six Antarctic macroalgal species from eulittoral (Pyropia endiviifolia, Iridaea cordata, Adenocystis utricularis and Monostroma hariotii) and sublittoral (Ascoseira mirabilis and Gigartina skottsbergii. RESULTS: Reproductive cells of eulittoral species showed the highest...
Tipo: Journal article
Palavras-chave: Antarctica; Reproductive cells; Seaweeds; Temperature; UV tolerance.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2016000100005

Photosynthetic UV stress tolerance of the Antarctic snow alga Chlorella sp. modified by enhanced temperature?
Provedor de dados: 97
Autores: Rivas,C.; Navarro,N.; Huovinen,P.; Gómez,I.
BACKGROUND: Photosynthetic characteristics and the effect of UV radiation and elevated temperature measured were studied in Chlorella sp. isolated from a snow microalgal community at King George Island, Maritime Antarctica through the chlorophyll florescence (rapid light curves and maximum quantum yield, respectively). The environmental context was monitored through measurements of spectral depth profiles of solar radiation (down to 40 cm) in the snowpack as well as a through continuous recording of temperature and PAR using dataloggers located at different depths (0-30 cm) within the snow column RESULTS: The photochemistry of Chlorella sp. was affected by UV radiation in a 12-h laboratory exposure under all studied temperatures (5, 10, 15, 20 °C): the...
Tipo: Journal article
Palavras-chave: Antarctica; Snow algae; Chlorella sp; Photosynthesis; UV radiation; Temperature.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2016000100006

Evolution of the Austral-Antarctic flora during the Cretaceous: New insights from a paleobiogeographic perspective
Provedor de dados: 97
Autores: LEPPE,MARCELO; MIHOC,MARITZA; VARELA,NATALIA; STINNESBECK,WOLFGANG; MANSILLA,HÉCTOR; BIERMA,HESSEL; CISTERNA,KATHERINE; FREY,EBERHARD; JUJIHARA,TOSHIRO.
Forest environments have continuously existed in Antarctica since the late Paleozoic and only disappeared from this continent since the Neogene. Nevertheless, the structure of these forests underwent substantial evolutionary changes. During the late Cretaceous, forests dominated by conifers and pteridophytes were gradually replaced by angiosperm-dominated forests. Elements common to these Antarctic forests are important constituents of the recent Valdivian Forest. During the Turonian stage of the Late Cretaceous, the Antarctic Peninsula and Patagonia were reconnected by a land bridge after a separation since the end of the Jurassic. Using biogeographic tools applied to the palynological and leaf imprint record, outcrops of Campanian-Maastrichtian age were...
Tipo: Journal article
Palavras-chave: Antarctica; Cretaceous; Magellan's basin; Paleobotany; Patagonia.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2012000400002

Reproductive output of mosses under experimental warming on Fildes Peninsula, King George Island, maritime Antarctica
Provedor de dados: 97
Autores: Casanova-Katny,A.; Torres-Mellado,G. A.; Eppley,S. M.
BACKGROUND: Mosses dominate much of the vegetation in the Antarctic, but the effect of climatic change on moss growth and sexual reproduction has scarcely been studied. In Antarctica, mosses infrequently produce sporophytes; whether this is due to physiological limitation or an adaptive response is unknown. We studied the effect of experimental warming (with Open Top Chambers, OTCs) on sporophyte production on Fildes Peninsula, King George Island for four moss species (Bartramia patens, Hennediella antárctica, Polytrichastrum alpinum, and Sanionia georgicouncinata). To determine whether reducing cold stress increases sexual reproduction as would be predicted if sex is being constrained due to physiological limitations, we counted sporophytes for these four...
Tipo: Journal article
Palavras-chave: Antarctica; Bryophyte; Climate change; Fildes Peninsula; King George Island; Sporophyte.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2016000100013

Independent effects of grazing and tide pool habitats on the early colonisation of an intertidal community on western Antarctic Peninsula
Provedor de dados: 97
Autores: Segovia-Rivera,V; Valdivia,N.
BACKGROUND: Prevailing environmental conditions can modulate the structuring role of biotic interactions. In intertidal habitats, less stressful environmental conditions and/or higher grazer densities may allow grazing effects to be stronger in tide pools than on emergent rocks. To test this hypothesis, we conducted a manipulative experiment on an intertidal rocky shore in Fildes Bay, King George Island, in which the effect of the dominant grazer Nacella polaris on the structure of benthic periphyton communities was compared between emergent rock and tide pool habitats. Also, we determined the spatial variation in density, weight, and maximum length of individuals of N. polaris in both habitats RESULTS: The density of N. polaris was significantly larger in...
Tipo: Journal article
Palavras-chave: Antarctica; Environmental stress model; Grazing; Herbivory; Intertidal; Nacella polaris; Periphyton.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2016000100003

Antarctic sponges (Porifera, Demospongiae) of the South Shetland Islands and vicinity: part I. Spirophorida, Astrophorida, Hadromerida, Halichondrida and Haplosclerida
Provedor de dados: 104
Autores: Campos,Maurício; Mothes,Beatriz; Veitenheimer Mendes,Inga L.
The aim of this work is to redescribe 11 species of sponges collected through the Brazilian Antarctic Program (PROANTAR), at the South Shetland Islands and vicinity. New information is provided on the Antarctic sponge fauna, in regard to species richness and the geographical and bathymetric distributions of identified species. The following species were identified and are here illustrated and fully described: Cinachyra antarctica (Carter, 1872), Cinachyra barbata Sollas, 1886, Craniella leptoderma (Sollas, 1886), Tethyopsis longispinum (Lendenfeld, 1907), Polymastia invaginata Kirkpatrick, 1907, Homaxinella balfourensis (Ridley &amp;amp; Dendy, 1886), Suberites montiniger Carter, 1880, Halichondria (Eumastia) attenuata (Topsent, 1915), Haliclona...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Antarctica; PROANTAR; Taxonomy.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752007000300021

Antarctic sponges (Porifera, Demospongiae) of the South Shetland Islands and vicinity: part II. Poecilosclerida
Provedor de dados: 104
Autores: Campos,Maurício; Mothes,Beatriz; Veitenheimer Mendes,Inga L.
In the present study 16 species are registered for the South Shetland Islands and vicinity: Acanthorhabdus fragilis Burton, 1929, Iophon unicornis Topsent, 1907, Clathria (Axosuberites) flabellata (Topsent, 1916), Clathria (Axosuberites) nidificata (Kirkpatrick, 1907), Kirkpatrickia variolosa (Kirkpatrick, 1907), Myxodoryx hanitschi (Kirkpatrick, 1907), Iotroata somovi (Koltun, 1964), Tedania (Tedaniopsis) charcoti (Topsent, 1907), Tedania (Tedaniopsis) vanhoffeni (Hentschel, 1914), Tedania (Tedaniopsis) oxeata (Topsent, 1916), Isodictya kerguelenensis (Ridley &amp;amp; Dendy, 1886), Isodictya lankesteri (Kirkpatrick, 1907), Isodictya toxophila Burton, 1932, Isodictya bentarti Ríos, Cristobo &amp;amp; Urgorri, 2004, Latrunculia (Latrunculia) brevis Ridley...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Antarctica; New occurrences; PROANTAR; Taxonomy.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752007000300027

A methodological proposal for the recovery of palynomorphs from snow and ice samples
Provedor de dados: 39
Autores: Rodrigues,Luiz Antonio da Costa; Agostini,Kamila da Matta; Alencar,Alexandre Santos de; Mendonça,Cláudia Barbieri Ferreira; Carvalho,Marcelo Araújo de; Gonçalves-Esteves,Vania.
ABSTRACT The procedures for a set of techniques to recover grains of pollen 26 and spores from liquid samples are described. Liquefied samples of matrices, such as melting lakes, snow and ice, can provide a record of climatic and environmental events at different geographic and temporal scales. The need for standardization of techniques was demonstrated in research carried out with matrices of snow and water of thawing lakes and snow collected on King George and Joinville islands (Antarctica). The use of the methods described can permit increased rescue of palynomorphs from liquid matrices, thereby adding greater reliability to palynological data and its use as a biotracer of environmental events. Methods of sieving and centrifugation were tested, and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Antarctica; Ice; Spores; Snow; Technique to recover grains of pollen.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062018000400667

The "New Approach to Corystospermales" and the Antarctic Fossil Record: A Critique
Provedor de dados: 41
Autores: Axsmith,Brian J.; Taylor,Edith L.; Taylor,Thomas N.
Much is now known about the Mesozoic pteridosperm order Corystospermales based on over seventy years of research. However, several concepts of corystosperm evolution have been proposed that avoid well-established phylogenetic methodology and arbitrarily discount evidence of the group from Antarctica. Here, we focus on the "New approach to Corystospermales" published by Artabe and Brea, which establishes a phylogeny for corystosperms based mainly on a restricted concept of anomalous wood anatomy in this group, and assumed relationships with cycads and medullosan pteridosperms. These authors also question evidence regarding attached corystospermalean organs from Antarctica. Based on a reconsideration of the Antarctic record, we reaffirm the evidence for a...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Antarctica; Corystospermales; Dicroidium; Gondwana; Phylogeny; South America; Triassic; Seed ferns.
Ano: 2007
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0002-70142007000100017

Santonian dinocyst assemblages of the Santa Marta Formation, Antarctic Peninsula: Inferences for paleoenvironments and paleoecology
Provedor de dados: 42
Autores: CASTRO,SUSAN P.; CARVALHO,MARCELO A.
To better understand the paleoenvironments of the lower-middle Santonian, dinocyst data were obtained from the Santa Marta Formation, Larsen Basin, James Ross Island, Antarctic Peninsula. This study provides the first available quantitative dinocyst data for the Santa Marta Formation, which should more clearly reflect detailed changes in paleoenvironments, as recorded by fluctuations in diversity and abundance. To record the Santonian dinocyst assemblages from the Larsen Basin, 30 samples from an outcrop of the Lachman Crags Member (LC section) were analyzed. These assemblages are dominated by peridiniacean dinocysts typical of the Isabelidinium flora. A lower-middle Santonian age was determined after the recognition of Odontochitina poriferaand...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Santonian dinocysts; Antarctica; Cretaceous; Santa Marta Formation; Dinocyst blooms.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652015000401583

Phaeosphaeria deschampsii (Ascomycota): A new parasite species of Deschampsia antarctica (Poaceae) described to Antarctica
Provedor de dados: 42
Autores: PUTZKE,JAIR; PEREIRA,ANTONIO B.
ABSTRACT This study presents the description of Phaeosphaeria deschampsii, which was found in plant communities from Half Moon Island, South Shetland Archipelago, Antarctica, in February 2014. Many patches of Deschampsia antarctica (Poaceae), the only indigenous Poaceae specie in Antarctic, were found dead, parasitized by a fungi pathogen. Based on the shape of its perithecia, with oblique neck, erumpent in the grass tissues, ascospore form and septation, the specie was identified as new to science.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Antarctica; Ascomycota; Grass; Phytopathology.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652016000501967

Pterodactyloid pterosaur bones from Cretaceous deposits of the Antarctic Peninsula
Provedor de dados: 42
Autores: KELLNER,ALEXANDER W.A.; RODRIGUES,TAISSA; COSTA,FABIANA R.; WEINSCHÜTZ,LUIZ C.; FIGUEIREDO,RODRIGO G.; SOUZA,GEOVANE A. DE; BRUM,ARTHUR S.; ELEUTÉRIO,LÚCIA H.S.; MUELLER,CARSTEN W.; SAYÃO,JULIANA M.
Abstract Fossil vertebrates from Antarctica are considerably rare, hampering our understanding of the evolutionary history of the biota from that continent. For several austral summers, the PALEOANTAR project has been carrying out fieldwork in the Antarctic Peninsula in search for fossils, particularly Cretaceous vertebrates. Among the specimens recovered so far are two bones referable to Pterosauria, more specifically to the Pterodacyloidea, the first volant reptiles from Antarctica to be fully described. MN 7800-V (part and counterpart) was recovered from a moraine at the Abernathy Flats (Santa Marta Formation, Lachman Crags Member, Santonian-Campanian) on James Ross Island. It is interpreted as the distal articulation of a first phalanx of the wing...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Antarctica; Antarctic Peninsula; Pterosauria; PALEOANTAR; Cretaceous.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652019000400519

The Brazilian research contribution to knowledge of the plant communities from Antarctic ice free areas
Provedor de dados: 42
Autores: PEREIRA,ANTONIO B.; PUTZKE,JAIR.
This work aims to summarize the results of research carried out by Brazilian researchers on the plant communities of Antarctic ice free areas during the last twenty five years. Since 1988 field work has been carried out in Elephant Island, King George Island, Nelson Island and Deception Island. During this period six papers were published on the chemistry of lichens, seven papers on plant taxonomy, five papers on plant biology, two studies on UVB photoprotection, three studies about the relationships between plant communities and bird colonies and eleven papers on plant communities from ice free areas. At the present, Brazilian botanists are researching the plant communities of Antarctic ice free areas in order to understand their relationships to soil...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Scientific publication; Botany; South Shetlands Island; Antarctica.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652013000300923

Occurrence of arbuscular mycorrhizal fungi on King George Island, South Shetland Islands, Antarctica
Provedor de dados: 42
Autores: BARBOSA,MARISÂNGELA V.; PEREIRA,ELISMARA A.; CURY,JULIANO C.; CARNEIRO,MARCO A.C.
ABSTRACT Arbuscular mycorrhizal fungi make up an important ecological niche in ecosystems, and knowledge of their diversity in extreme environments is still incipient. The objective of this work was to evaluate the density and diversity of arbuscular mycorrhizal fungi in the soil of King George Island in the South Shetland Islands archipelago, Antarctica. For that, soil and roots of Deschampsia antarctica were collected at the brazilian research station in Antarctica. The spore density, species diversity and mycorrhizal colonization in the roots were evaluated. There was a low density of spores (27.4 ± 17.7) and root mycorrhizal colonization (6 ± 5.1%), which did not present statistical difference. Four species of arbuscular mycorrhizal fungi were...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Antarctica; Deschampsia antarctica; Low temperatures; Mycorrhizal fungi.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652017000401737

Detection of proteases from Sporosarcina aquimarina and Algoriphagus antarcticus isolated from Antarctic soil
Provedor de dados: 42
Autores: Santos,Anderson F.; Pires,Fabiano; Jesus,Hugo E.; Santos,André L.S.; Peixoto,Raquel; Rosado,Alexandre S.; D'Avila-Levy,Claudia M.; Branquinha,Marta H.
Two psychrophilic bacterial samples were isolated from King George Island soil, in Antarctica. The phylogenetic analysis based on the 16S rRNA (rrs) gene led to the correlation with the closest related isolates as Sporosarcina aquimarina (99%) and Algoriphagus antarcticus(99%), with query coverage of 99% and 98%, respectively.The spent culture media from both isolates displayed proteolytic activities detected by sodium dodecyl sulfate polyacrylamide gel electrophoresis containing gelatin as protein substrate. Under the employed conditions, S. aquimarina showed a 55 kDa protease with the best activity detected at pH 7.0 and at 27°C. A. antarcticusalso showed a single extracellular protease, however its molecular mass was around 90kDa and its best activity...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Algoriphagus antarcticus; Antarctica; Sporosarcina aquimarina; Protease.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652015000100109

Soluble carbohydrate content variation in Sanionia uncinata and Polytrichastrum alpinum, two Antarctic mosses with contrasting desiccation capacities
Provedor de dados: 48
Autores: Zúñiga-González,Paz; Zúñiga,Gustavo E; Pizarro,Marisol; Casanova-Katny,Angélica.
BACKGROUND: Cryptogamic vegetation dominates the ice-free areas along the Antarctic Peninsula. The two mosses Sanionia uncinata and Polytrichastrum alpinum inhabit soils with contrasting water availability. Sanionia uncinata grows in soil with continuous water supply, while P. alpinum grows in sandy, non-flooded soils. Desiccation and rehydration experiments were carried out to test for differences in the rate of water loss and uptake, with non-structural carbohydrates analysed to test their role in these processes. RESULTS: Individual plants of S. uncinata lost water 60 % faster than P. alpinum; however, clumps of S. uncinata took longer to dry than those of P. alpinum (11 vs. 5 h, respectively). In contrast, rehydration took less than 10 min for both...
Tipo: Journal article
Palavras-chave: Antarctica; Antarctic vegetation; Bryophytes; Sugars.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602016000100006

Study of the Lange Glacier and its impact due to temperature increase in Admiralty Bay, King George Island, Antarctica
Provedor de dados: 50
Autores: Mojica-Moncada,Diego F.; Cárdenas,Carlos; Mojica-Moncada,Jhon F.; Brondi,Fabian; Barragán-Barrera,Dalia C.; Marangunic,Cedomir; Holland,David; Franco Herrera,Andrés; Casassa,Gino.
ABSTRACT In the western Antarctic Peninsula one of the areas the highest warming in the southern hemisphere has been identified. To characterize this tendency, we selected the Lange Glacier (LG) on King George Island, to evaluate: 1) LG surface temperature and dynamics using stakes with temperature data loggers; 2) LG submerged thickness and sea parameters through bathymetry (BT) and 29 CTD stations in front of LG; 3) glacier front (GF) using BT and a Digital Elevation Model (DEM); 4) change in GF position using DEM and historical data of GF width; 5) Calving flux (QC). Our findings showed 85 % of temperatures were above the 0 °C melting point (mean = 5.0 ± 5.2 °C). The stakes had an average ice loss of 9.3 ± 1.3 cm. The LG mean dynamics was 8.8 ± 1.5 m...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Lange Glacier; Melting; Climate change; Calving flux; Antarctica.
Ano: 2021
URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0122-97612021000300059

The moss flora of Ostrov Geologov (Geologists Island), Maxwell Bay, King George Island, Antarctica
Provedor de dados: 51
Autores: Câmara,Paulo E.A.S; Guedes Costa Silva,Barbara; Carvalho-Silva,Micheline; Knop Henriques,Diego.
Located of the east coast of Fildes Peninsula, South of Ardley Island, at King George Island, Ostrov Geologov (Geologist Islands) is a small island with 0.25 miles long. It only had one plant record published so far. We have conducted extensive fieldwork on the site and provide here a comprehensive checklist and a key for the moss species occurring on the island. Despite its small size, theislandcontains about 35% of all theFildes Peninsula moss flora, six new records were found. The pristine state of the island due to its relative isolation, presence of avian nesting sites and a relatively rich moss flora are strong arguments in favor of protection status for the island.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Antarctica; Bryophyta; Fildes Peninsula; Moss.
Ano: 2017
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S1851-23722017000200004

Morphology and ecology of bivalve molluscs from Admiralty Bay, King George Island, Antarctica
Provedor de dados: 52
Autores: Absher,Theresinha M.; Feijó,Angela R.
Bivalve species were collected from shallow coastal areas of King George Island (Martel, Mackellar and Ezcurra Inlets of Admiralty Bay). Twenty one species belonging to 16 genera and 12 families were identified and their morphometric and morphological shell characteristics were described. Three main characteristics were found to be common to the majority of the bivalve species sampled: 1) thin fragile shells; 2) small size of individuals (76%), and 3) the lack of true cardinal teeth (72%). Comparison of calcium data from a tropical estuary and a subantarctic coastal shallow area suggested that the calcium in the sea water was not a constraint to shell building but shell thickness could be an adaptation to the efficiency of energy partitioning. Small...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bivalve species; Antarctic bivalves; King George Island; Antarctica.
Ano: 1998
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89131998000400008

Movement of southern elephant seals (Mirounga leonina L.) from Elephant Is. South Shetlands, Antarctica
Provedor de dados: 52
Autores: Muelbert,Mônica M. C.; Robaldo,Ricardo B.; Martínes,Pablo E.; Colares,Elton P.; Bianchini,Adalto; Setzer,Alberto.
In 1999, at-sea activity of two young southern elephant seal males (Mirounga leonina) from Elephant Is. (61º13'S, 55º23'W), Antarctica, was monitored and tracked for 9 months. The individuals were randomly selected, captured, sedated (Zoletil 50®- 1mg/kg), weighed, measured, bled, paint-marked and fitted with satellite tags (STDR - ST-6PPT, Telonics®, USA). Deployment of the STDR took about 45 min since each animal had a lower incisor tooth extracted for age determination. The seals exhibited individual behaviors. Seal "V"-23842 (BM ~ 801kg) moved from Elephant Is. (61.2ºS 55.3ºW) in Jan. 1999 to King George Is. (62.2ºS 58.1ºW) in Feb. 1999 when the tag stopped signaling. Seal "T"-23843 (BM ~ 656 kg) was restricted to the area around Elephant Is. (61.2ºS...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Mirounga leonina; Southern elephant seals; Satellite telemetry; Antarctica; At-sea activity.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132004000300017

A new mini box corer for sampling muddy bottoms in antarctic shallow waters
Provedor de dados: 52
Autores: Echeverría,Carlos Alejandro; Lavrado,Helena Passeri; Campos,Lúcia; Paiva,Paulo Cesar de.
A new Mini Box Corer (MBC-GEAMB) was developed for bottom sampling in Antarctic shallow waters down to 100 m depth from a small vessel. It consists of a detachable stainless steel box with a total sampling area of 0.0625 m², and a closing arm with a detachable blade without an external frame. MBC allowed stratified bottom sampling and good quality samples comparable to those obtained through diving. A comparison between the MBC-GEAMB and a 0.056 m²van Veen grab (VV) was undertaken for the benthic macrofaunal composition in Admiralty Bay, King George Island (Antarctica). MBC and VV samples were taken from three depths (20, 30 and 60m) in two sites. Total densities sampled with the MBC were up to 10 times higher than those obtained with van Veen grab. VV...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Mini box-corer; Antarctica; Benthos; Sampling.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132009000300015

The diversity, extracellular enzymatic activities and photoprotective compounds of yeasts isolated in Antarctica
Provedor de dados: 58
Autores: Vaz,Aline B. M; Rosa,Luiz H; Vieira,Mariana L. A; Garcia,Virginia de; Brandão,Luciana R; Teixeira,Lia C. R. S; Moliné,Martin; Libkind,Diego; van Broock,Maria; Rosa,Carlos A.
The diversity of yeasts collected from different sites in Antarctica (Admiralty Bay, King George Island and Port Foster Bay and Deception Island) and their ability to produce extracellular enzymes and mycosporines were studied. Samples were collected during the austral summer season, between November 2006 and January 2007, from the rhizosphere of Deschampsia antarctica, ornithogenic (penguin guano) soil, soil, marine and lake sediments, marine water and freshwater from lakes. A total of 89 isolates belonging to the following genera were recovered: Bensingtonia, Candida, Cryptococcus, Debaryomyces, Dioszegia, Exophiala, Filobasidium, Issatchenkia (Pichia), Kodamaea, Leucosporidium, Leucosporidiella, Metschnikowia, Nadsonia, Pichia, Rhodotorula, and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Yeasts; Antarctica; Diversity; Extracellular enzymes; Mycosporines.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822011000300012

Phylogenetic MLSA and phenotypic analysis identification of three probable novel Pseudomonas species isolated on King George Island, South Shetland, Antarctica
Provedor de dados: 58
Autores: Vásquez-Ponce,Felipe; Higuera-Llantén,Sebastián; Pavlov,María S.; Marshall,Sergio H.; Olivares-Pacheco,Jorge.
ABSTRACT Antarctica harbors a great diversity of microorganisms, including bacteria, archaea, microalgae and yeasts. The Pseudomonas genus is one of the most diverse and successful bacterial groups described to date, but only eight species isolated from Antarctica have been characterized. Here, we present three potentially novel species isolated on King George Island. The most abundant isolates from four different environments, were genotypically and phenotypically characterized. Multilocus sequence analysis and 16S rRNA gene analysis of a sequence concatenate for six genes (16S, aroE, glnS, gyrB, ileS and rpoD), determined one of the isolates to be a new Pseudomonas mandelii strain, while the other three are good candidates for new Pseudomonas species....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Pseudomonas; Antarctica; P. fluorescens complex; Multilocus Sequence Analysis.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822018000400695