Found 14089 items
1 January, 2008 by Kevin Newsham
The pathogenicity of an isolate of a Pythium species from Signy Island in the South Orkney Islands was tested against the Antarctic hairgrass Deschampsia antarctica. The isolate was found to…1 January, 2008
The hypothesis that ITS structural features can be used to define fungal groups, where sequence analysis is unsatisfactory, was examined in plant and animal pathogenic fungi. Structural models of ITS1…1 January, 2008
Twenty-six isolates of Colletotrichum kahawae, the causal agent of coffee berry disease, from coffee in Africa, and 25 isolates, mostly of Colletotrichum gloeosporioides, from coffee and other tropical perennial crops,…1 January, 2008
The taxonomy and nomenclature of the fungus commonly referred to as Stropharia aurantiaca was investigated. Molecular analysis of the ribosomal RNA large subunit gene confirmed the exclusion of the species…1 January, 2008
A reference checklist has been compiled giving the names of all species of non-lichenized fungi described by collection, observation or culture from the general Antarctic region since records were first…1 January, 2008
We determined growth rates of six coccolithophorid strains (five species) as a function of temperature. We grew four strains (three species: Emiliania huxleyi, Gephyrocapsa oceanica, and two strains of Calcidiscus…Read more on Growth rates of six coccolithophorid strains as a function of temperature.
1 January, 2008
Geological analysis of 5-10-m-long sediment cores in the context of the anthropologically derived materials within them has allowed us to identify ancient landscape features in the Theban area around Luxor,…1 January, 2008
1. The concept of integrated ecosystem conservation is widely supported as a framework to achieve sustainable management of biodiversity. However, paucity of data and limited methodological tools reduce its application…Read more on A species approach to marine ecosystem conservation
1 January, 2008 by Lloyd Peck
Active metabolic suppression in anticipation of winter conditions has been demonstrated in species of mammals, birds, reptiles and amphibians, but not fish. This is because the reduction in metabolic rate…Read more on Hibernation in an Antarctic fish: on ice for winter
1 January, 2008
The anamorphic species Colletotrichum gloeosporioides has never been adequately typified according to modern nomenclatural practice, resulting in uncertainty as to application of the named A lectotype specimen is therefore designated…Read more on The typification of Colletotrichum gloeosporioides
1 January, 2008 by Peter Convey
Background: Mitogenomics data, i.e. complete mitochondrial genome sequences, are popular molecular markers used for phylogenetic, phylogeographic and ecological studies in different animal lineages. Their comparative analysis has been used to…1 January, 2008 by Michael Meredith
Polar regions are particularly sensitive to climate change, with the potential for significant feedbacks between ocean circulation, sea ice, and the ocean carbon cycle. However, the difficulty in obtaining in…Read more on Southern Ocean frontal structure and sea ice formation rates revealed by elephant seals
1 January, 2008 by Gareth Chisham, Mai Mai Lam, Mervyn Freeman, Michael Pinnock
Magnetic reconnection is the most significant process that results in the transport of magnetised plasma into, and out of, the Earth's magnetosphere-ionosphere system. There is also compelling observational evidence that…1 January, 2008 by Melody Clark
Physiological adaptation to increased environmental temperatures has been studied experimentally in a number of fish species, with the up-regulation of several genes identified as being associated with the process, such…1 January, 2008 by Lloyd Peck, Melody Clark
Members of the HSP70 gene family comprising the constitutive (HSC70) and inducible (HSP70) genes, plus GRP78 (Glucose-regulated protein 78 kDa) were surveyed for expression levels via Q-PCR after both an…Read more on The HSP70 heat shock response in the Antarctic fish Harpagifer antarcticus.
1 January, 2008 by Lloyd Peck, Melody Clark
The success of any organism depends not only on niche adaptation but also the ability to survive environmental perturbation from homeostasis, a situation generically described as stress. Although species-specific mechanisms…Read more on Antarctic marine molluscs do have an HSP70 heat shock response
1 January, 2008 by Lloyd Peck, Melody Clark
Members of the HSP70 gene family comprising the inducible (HSP70) genes and GRP78 (glucose-regulated protein 78 kDa) were identified in an Antarctic sea star (Odontaster validus) and an Antarctic gammarid…Read more on Lack of an HSP70 heat shock response in two Antarctic marine invertebrates
1 January, 2008 by David Barnes, Lloyd Peck, Melody Clark, Paul Geissler
Heat shock proteins (HSPs) are a family of genes classically used to measure levels of organism stress. We have previously identified two HSP70 genes (HSP70A and HSP70B) in sub-tidal populations…Read more on Low heat shock thresholds in wild Antarctic intertidal limpets (Nacella concinna).
1 January, 2008 by Roger Worland, Melody Clark
Insects vary considerably in their ability to survive low temperatures. The tractability of these organisms to experimentation has lead to considerable physiology-based work investigating both the variability between species and…Read more on How insects survive the cold: molecular mechanisms – a review
1 January, 2008 by Andrew Clarke
Although biological work in the Southern Ocean extends back well over a century, studies in the past two decades have changed significantly our understanding of the ecology, diversity, biogeography and…Read more on Antarctic marine benthic diversity: patterns and processes
1 January, 2008 by Andrew Clarke
Elemental (C, N, P) composition was examined in 6 benthic marine invertebrates from Antarctica: 2 suspension feeders (the holothurian Heterocucumis steineni and the polychaete Thelepus cincinnatus), 1 epifaunal grazer (the…Read more on Ecological stoichiometry in six species of Antarctic marine benthos
1 January, 2008 by Andrew Clarke, Michael Meredith
We report data from the first 8 years of oceanographic monitoring in Ryder Bay, northern Marguerite Bay, Antarctica. These data form the oceanographic component of the Rothera Oceanographic and Biological…1 January, 2008 by Andrew Clarke
We examine variation associated with phylogeny in the scaling of body temperature in endotherms, using data from 596 species of mammal and 490 species of bird. Among higher groups of…Read more on Scaling of body temperature in mammals and birds
1 January, 2008 by Andrew Clarke
Antarctic krill (Euphausia superba) is a large euphausiid, widely distributed within the Southern Ocean [1], and a key species in the Antarctic food web [2]. The Discovery Investigations in the…Read more on Adult Antarctic krill feeding at abyssal depths
1 January, 2008 by Mark Clilverd, Neil Cobbett, Tracy Moffat-Griffin
Geosynchronous Los Alamos National Laboratory (LANL-97A) satellite particle data, riometer data, and radio wave data recorded at high geomagnetic latitudes in the region south of Australia and New Zealand are…1 January, 2008 by Mark Clilverd, Nigel Meredith
The principal loss mechanism for electrons from the inner radiation belt (1.2 < L < 2.0) and slot region (2.0 < L < 3.0) is atmospheric precipitation driven by several…Read more on Ground-based transmitter signals observed from space: Ducted or nonducted?
1 January, 2008
The reproductive performances of Grey-headed Albatrosses Diomedea chrysostoma with a previous record (≤5 years) of consistent success (≤70% chicks fledged from eggs laid—“top” birds) or failure (≤ 70% of attempts…1 January, 2008 by Martin Collins, Sophie Fielding
The distribution, total length (L-T) frequency and diet of Patagonotothen guntheri are described from 14 bottom trawl surveys conducted on the Shag Rocks and South Georgia shelves in the austral…1 January, 2008 by Dominic Hodgson, Claus-Dieter Hillenbrand, Peter Convey
Antarctica is a continent locked in ice, with almost 99.7% of current terrain covered by permanent ice and snow, and clear evidence that, as recently as the Last Glacial Maximum…Read more on Antarctic terrestrial life – challenging the history of the frozen continent?
1 January, 2008 by David Vaughan, Hugh Corr
Indirect evidence suggests that volcanic activity occurring beneath the West Antarctic ice sheet influences ice flow and sheet stability(1-3). However, only volcanoes that protrude through the ice sheet(4) and those…Read more on A recent volcanic eruption beneath the West Antarctic ice sheet
1 January, 2008 by Claus-Dieter Hillenbrand
Sediment drifts on the continental rise are located proximal to the western side of the Antarctic Peninsula and recorded changes in glacial volume and thermal regime over the last ca.…1 January, 2008 by Sandra McInnes, Sandra McInnes
Remains of tardigrades have rarely been reported to preserve in sediments, resulting in the absence of important ecological and biogeographic information that they could provide. However, a study of faunal…1 January, 2008 by Philip Leat, Teal Riley
The Mesozoic dyke swarms of Western Dronning Maud Land, Antarctica, form a minor intrusive component of the Karoo large igneous province. Five-hundred and sixty one dykes were recorded intruding Neoproterozoic…1 January, 2008
The influence of snow microstructure on thermal and radiative transfer in snow has not been thoroughly investigated as the tools necessary to efficiently measure microstructural geometry at millimeter resolution have…1 January, 2008 by Richard Horne
The arrival of high-speed solar wind streams (HSSs) at the Earth's magnetopause drives particle and wave phenomena that are distinct from the phenomena caused by other solar wind structures. Although…Read more on High-speed solar wind streams: a call for key research
1 January, 2008 by Fausto Ferraccioli, Tom Jordan
Recent satellite observations of Thwaites Glacier in the Amundsen Sea Embayment, West Antarctica, have shown that the glacier is changing rapidly. The causes of its dynamic behavior are uncertain but…Read more on First airborne gravity results over the Thwaites Glacier catchment, West Antarctica
1 January, 2008 by Claus-Dieter Hillenbrand, Robert Larter
A 330-km length of the little known continental shelf edge and slope of the Bellingshausen Sea, West Antarctica, is investigated using multibeam swath-bathymetric and sub-bottom profiler evidence. The shelf break…1 January, 2008
The new Horizontal Wind Model (HWM07) provides a statistical representation of the horizontal wind fields of the Earth's atmosphere from the ground to the exosphere (0-500 km). It represents over…Read more on An empirical model of the Earth’s horizontal wind fields: HWM07
1 January, 2008 by Richard Hindmarsh, Richard Hindmarsh
Ribbed moraines are large (up to 16 km long) ridges of sediment produced transverse to ice flow direction that formed widely beneath palaeo-ice sheets. Since ice sheet stability is sensitive…1 January, 2008 by Lloyd Peck
The world's oceans are slowly becoming more acidic. In the last 150 yr, the pH of the oceans has dropped by similar to 0.1 units, which is equivalent to a…1 January, 2008
1. Ecologists are obtaining ever-increasing amounts of data concerning animal movement. A movement strategy that has been concluded for a broad variety of animals is that of Lévy flights, which…1 January, 2008
The Antarctic Tropospheric Chemistry Investigation (ANTCI) was carried out from late November to December 2003 with both extended ground-based and tethered balloon studies at Amundsen Scott Station, South Pole. ANTCI…Read more on Antarctic Tropospheric Chemistry Investigation (ANTCI) 2003 overview
1 January, 2008 by David Vaughan
The East Antarctic Ice Sheet is the largest, highest, coldest, driest, and windiest ice sheet on Earth. Understanding of the surface mass balance (SMB) of Antarctica is necessary to determine…1 January, 2008
Life, as we know it, is constrained by various environmental parameters ( physical and chemical) and these vary both in space and time. Combinations of specific ranges for each of…1 January, 2008
We present a global empirical disturbance wind model (DWM07) that represents average geospace-storm-induced perturbations of upper thermospheric (200-600 km altitude) neutral winds. DWM07 depends on the following three parameters: magnetic…Read more on DWM07 global empirical model of upper thermospheric storm-induced disturbance winds
1 January, 2008 by Michael Rose, Richard Horne
Magnetic pulsations in the Pc1-Pc2 frequency range (0.1-5 Hz) are often observed on the ground and in the Earth's magnetosphere during the aftermath of geomagnetic storms. Numerous studies have suggested…1 January, 2008 by Dominic Hodgson, Roger Worland, Peter Convey
Inland Antarctic nunataks typically have simple physically weathered soils and limited ecosystem complexity. In this paper we present quantitative measurements of soil physical and chemical properties at one Antarctic nunatak.…Read more on Soil properties of an Antarctic inland site: implications for ecosystem development
1 January, 2008
Ice cores are a widely used archive to reconstruct past changes of the climate system. This is done by measuring the concentration of substances in the ice and in the…Read more on Continuous flow analysis of total organic carbon in polar ice cores
1 January, 2008 by Andrew Fleming
Pack ice and icebergs are two of the biggest hazards to shipping around Antarctica. Andrew Fleming and Paul Bowyer demonstrate how a new satellite system is protecting ships in the…1 January, 2008
The Trinity Peninsula Group (TPG) of northern Graham Land, a weakly metamorphosed thick sequence of predominantly quartz- and feldspar-rich greywacke, has tentatively been correlated with metasedimentary rocks exposed along the…1 January, 2008 by Nigel Meredith, Richard Horne, Sarah Glauert
A data-driven physical model of the energetic electrons in the Earth's radiation belts, called the Radiation Belt Environment (RBE) model, has been developed to understand Earth's radiation belt dynamics and…Read more on Radiation Belt Environment model: application to space weather nowcasting
1 January, 2008 by Eugene Murphy, Jaume Forcada, Philip Trathan
The consequences of warming for Antarctic long-lived organisms depend on their ability to survive changing patterns of climate and environmental variation. Among birds and mammals of different Antarctic regions, including…1 January, 2008 by Adrian Fox
Recent studies have reported widespread retreat and acceleration of glaciers on the Antarctic Peninsula, attributed to regional warming. The loss of ice is a contributor to sea-level rise, but its…1 January, 2008
Antarctic Base personnel live for 3 months in winter with no natural sunlight. This project compared sleep, by actigraphy, during periods of increased exposure to white light or blue enriched…1 January, 2008 by Alistair Crame
The evolution of Antarctic climate from a Cretaceous greenhouse into the Neogene icehouse is captured within a rich record of fossil leaves, wood, pollen, and flowers from the Antarctic Peninsula…Read more on 100 million years of Antarctic climate evolution: evidence from fossil plants
1 January, 2008 by Peter Fretwell
The use of digital terrain mapping in determining the anatomy of the Late Devensian British–Irish Ice Sheet at a resolution of 500m cell size is illustrated for Boulton et al.’s…1 January, 2008 by Andrew Clarke
Antarctic shallow-water and deep-sea echinoderms are known to have seasonal gametogenic cycles linked to seasonal pulses of phytodetritus produced in surface waters. We suggest that phytodetritus reaching the Antarctic continental…1 January, 2008 by Mark Clilverd
Enhancements of drift-loss cone fluxes in the inner radiation belt have been observed to coincide with the geographic location of the powerful VLF transmitter NWC. In this paper we expand…Read more on Radiation belt electron precipitation by man-made VLF transmissions
1 January, 2008 by Sandra McInnes, Sandra McInnes
Tardigrada is a phylum closely allied with the arthropods. They are usually less than 0.5 mm in length, have four pairs of lobe-like legs and are either carnivorous or feed…Read more on Global diversity of tardigrades (Tardigrada) in freshwater
1 January, 2008 by Geraint Tarling
Antarctic krill (Euphausia superba) is a keystone species in the southern ocean ecosystem where it is the main consumer of phytoplankton and constitutes the main food item of many higher…1 January, 2008
The coastal ocean provides nutrients to the open ocean in accounts that are poorly quantified. We use an ocean biogeochemistry model to assess the importance of the coastal nutrient supply…Read more on Importance of coastal nutrient supply for global ocean biogeochemistry
1 January, 2008 by Vsevolod Afanasyev
1. Investigations were made to determine whether the two giant petrel species segregate by gender and species in relation to the stage of the annual cycle. The individual foraging behaviour…1 January, 2008 by David Barnes, Huw Griffiths, Katrin Linse
An extremely dynamic chain of archipelagos links South America and the Antarctic Peninsula. It includes islands, which are large and small, old and young, near continental margins and isolated, and…Read more on Distribution of macrobenthic taxa across the Scotia Arc, Southern Ocean
1 January, 2008
Climate change is now evident also in Antarctica, with impacts both on the abiotic and the biotic components of ecosystems, particularly on permafrost, active layer thickness, vegetation, and soil properties.…1 January, 2008 by Joanne Johnson
The northern Antarctic Peninsula region has undergone similar to 10 m.y. of eruptive activity by basaltic volcanoes, mainly in subglacial settings. Spectacular exposures of lava-fed deltas, capped by basalt flows…1 January, 2008
The stone runs of the Falkland Islands are thought to be periglacial blockfields but their age and detailed origin remain enigmatic. We examine the fine sediments that underlie two stone…1 January, 2008 by Roger Worland, Peter Convey
In the maritime Antarctic, terrestrial arthropods have recourse to two strategies to mitigate low summer temperatures: (1) physiological plasticity and (2) avoidance via microhabitat insulation. This study investigated the interaction…1 January, 2008 by Roger Worland, Peter Convey
This study employed H-1 NMR spectroscopy to assay the metabolome of the high Arctic freeze-tolerant dipteran larvae, Heleomyza borealis, after recovery from exposure to a range of sub-zero temperature treatments.…Read more on Metabolomic fingerprint of cryo-stress in a freeze tolerant insect
1 January, 2008 by Roger Worland
Maturation to adulthood and successful reproduction in the Antarctic fairy shrimp, Branchinecta gaini, must be completed within a physiologically challenging temporal window of ca. 2.5 months in the southern Antarctic…1 January, 2008 by Roger Worland
A technique for rapidly measuring non-lethal thermal tolerance traits in small insects and terrestrial arthropods of similar size is described. Single or multiple individuals are heated or cooled in an…1 January, 2008
Continuous Plankton Recorder data suggest that the Irminger Sea supports a major proportion of the surface-living population of the copepod Calanus finmarchicus in the northern North Atlantic, but there have…Read more on Spatial demography of Calanus finmarchicus in the Irminger Sea
1 January, 2008
Preservation of ecosystem structure is the guiding principle by which the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) endeavors to manage the harvests of living resources of…Read more on Reconciling fisheries with conservation: three examples from the Southern Ocean
1 January, 2008 by Claus-Dieter Hillenbrand
Throughout the last decade large sediment drifts located on the upper continental rise west of the Antarctic Peninsula were the target of oceanographic measurements, bathymetric mapping, seismic investigations. shallow sediment…1 January, 2008 by Claus-Dieter Hillenbrand, Robert Larter
Three megascopic and disseminated tephra layers (which we refer to as layers A, B, and C) occur in late Quaternary glaciomarine sediments deposited on the West Antarctic continental margin. The…1 January, 2008
Vestimentiferan tubeworms are significant members of deep-sea chemosynthetically-driven communities, including hydrothermal vents and cold seeps. The reproductive condition in this taxon is rarely studied because of sampling constraints inherent to…1 January, 2008 by Peter Ward
The cyclopoid copepod Oithona similis is highly abundant and ubiquitous in the marine epipelagic environment, yet rates of mortality in this species have rarely been quantified; indeed we are lacking…Read more on Spring mortality of the cyclopoid copepod Oithona similis in polar waters
1 January, 2008 by Dominic Hodgson
1 January, 2008 by Paul Holland
Glaciological processes at grounding lines, which divide floating ice shelves from grounded ice sheets, may strongly influence the dynamics and evolution of inland ice. Therefore, understanding the oceanic forcing on…Read more on A model of tidally dominated ocean processes near ice shelf grounding lines.
1 January, 2008 by Adrian Jenkins, Paul Holland
A three-dimensional ocean general circulation model is used to study the response of idealized ice shelves to a series of ocean-warming scenarios. The model predicts that the total ice shelf…Read more on The response of ice shelf basal melting to variations in ocean temperature.
1 January, 2008 by Richard Horne, Sarah Glauert
According to existing theory, electrons are accelerated up to ultra-relativistic energies(1) inside Jupiter's magnetic field by betatron and Fermi processes as a result of radial diffusion towards the planet and…1 January, 2008 by Claire Waluda, Kevin Hughes
The short-term behavioural effects of helicopter overflights on breeding king penguins Aptenodytes patagonicus at South Georgia were examined. Seventeen helicopter overflights were made at altitudes between 230 and 1768 m…1 January, 2008 by Peter Ward
To date, little research has been carried out on pelagic gastropod molluscs (pteropods) in Southern Ocean ecosystems. However, recent predictions are that, due to acidification resulting from a business as…