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... Pieces of algal mats are pulled from bottoms of shallow ponds in Antarctica by melting ice in spring. Heat absorbed from the sun by the mats causes the mats to melt the overlying ice and they move to the surface. Once on the surface they dry and are blown away. ...
... Systematic observations on a beach at the Cape Crozier, Antarctica Adelie Penguin (Pygoscelis adeliae) rookery provided data on the effects and form of Leopard Seal (Hydruga leptonyx) predation on adult and young penguins. Active predation, involving up to four seals, was observed during 56% of the time with average kill rates of 0.61 birds/hr. Predation rates increased with the height of incoming ...
... The object of this paper is to discuss the relationship of the Weddell seal (Leptonychotes weddelli) to its habitat, the fast ice of Antarctica. Movements and distribution of Weddell seals during summer are governed by presence of fast ice and availability of breathing and exit holes. It is suggested that this applies during winter also. Local populations are relatively discrete and there is limit ...
... Cinder cones that arose December 1967 within Telefon Bay, Deception Island, Antarctica, were investigated 1 year later to determine the establishment of microorganisms and cryptogams. Culture media were inoculated to determine the presence and abundance of algae, fungi, heteorotrophic and chemoautotrophic, aerobic, microaerophilic, and anaerobic bacteria. No mosses or lichens had become establishe ...
... Bacterial counts were generally higher and molds were much more extensive and widely distributed at Paradise Harbor on the Antarctic Peninsula, well above the Antarctic Circle, than in areas to the south. Thermophilic bacteria were found only in soils that had been disturbed or contaminated by man and other animals. Mesophilic counts on media made with deionized or sea water, with few exceptions, ...
... Sections Naevosa M. P. Chr., Crocea M. P. Chr. and Macrodonta M. P. Chr. are reduced to subsectional rank in section Spectabilia Dahlst. of the genus Taraxacum. Section Arctica Dahlst. (section Laevia (Hand.-Mazz.) Schischk.) is enlarged by including sections Glabra Dahlst., Antarctica Hand.-Mazz. and Pachera v. Soest. Taraxacum gurglense A. J. Richards and T. unicoloratum A. J. Richards (section ...
... Studies of the benthos between 30 and 60 m at Cape Armitage, McMurdo Sound. Antarctica, reveal an epifaunal community in which sponges and their asteroid and nudibranch predators predominate. Field experiments demonstrated that, with the exception of Mycale accrata, the growth rates of the sponges are too slow to measure in one year. Mycale, however, was observed to increase its mass as much as 67 ...
... A breeding population of the Weddell seal (Leptonychotes weddelli) was studied annually during the 2 1/2—mo pupping and breeding season in McMurdo Sound, Antarctica, from 1969 through 1974. Components of the population were estimated by direct counts of adult ♂ ♂ with pups, by capture—recapture studies of nonparous ♀ ♀ and adult ♂ ♂, and by aerial counting. Total population size was estimated as b ...
... Soils were examined on moraines deposited by Taylor Glacier in lower Taylor Valley to determine changes in soil properties with time in an environment of extreme cold and aridity and minimal biologic activity. The soils range in age from 200,000 to 2.7-3.5 million years BP. Soil profiles contain a desert pavement over a weakly expressed B horizon, followed by permafrost, which may be “dry” or ice- ...
... Three distinct population strategies were observed within the summer algal plankton of Lake Fryxell (Taylor Valley, South Victoria Land, 77°35'S, 163°15'E). Phytoplankton immediately under the ice (Ochromonas and Chlamydomonas) were adapted to relatively bright light but were limited by nitrogen availability. A deep maximum of Chroomonas and Pyramimonas was recorded at the bottom of the euphotic z ...
... Two bryophyte—dominated communities in the maritime Antarctic are analyzed in terms of the transfer and standing crops of organic matter within them. A moss turf dominated by Polytrichum alpestre and Chorisodontium aciphyllum and a moss carpet composed of Calliergon sarmentosum, Calliergidium austro—stramineum, and Drepanocladus uncinatus with the liverwort Cephaloziella varians were investigated ...
... The polar ice sheets of Greenland and Antarctica are unique sedimentary environments which offer valuable information on the climate and atmospheric environment of the past. The prevailing low temperatures, lack of mixing of strata, and relatively high accumulation rates result in high quality records which may be resolved in great detail, frequently at the scale of seasons of the year. Deformatio ...
... Although several invertebrates have been introduced by Man into the Antarctic, no holometabolous insects have survived to colonize terrestrial habitats successfully. Data are presented on the survival of populations of a chironomid midge, together with an enchytraeid worm, for 17 years in a maritime Antarctic site at Signy Island, South Orkney Islands. Both species are thought to have been introdu ...
Chironomidae; instars; larvae; life history; midges; Antarctic region; Antarctica
Abstract:
... The morphological variation of adult Parochlus steinenii (Gerke) is described from measurements of two populations from the South Shetland Islands. Morphologically, the population from Ardley Island is significantly larger than the population from Livingston Island, and in both populations variation in forefemur length is generally greater than variation in either antennal or wing length. The fina ...
... Ecological segregation among Adelie, Gentoo, and Chinstrap penguins during summer results from differences in breeding chronology, foraging behaviors, and life history tactics. To determine the importance of these factors in segregating the niches of the three species, we collected data on their population size, breeding success, breeding chronology, feeding frequency, and foraging range. Gentoo P ...
... Primary anatomy and secondary development is described for two root types from the Fremouw Peak locality (Transantarctic Mts, Antarctica) of early to middle Triassic age. Roots of Antarcticycas have a bilayered cortex with thick surface cuticle, diarch xylem, and a clearIy defined endodermis surrounded by a single cell layer possessing phi thickenings. Secondary development begins with phellern an ...
Pinnipedia; adults; aerial surveys; age structure; breeding; dogs; females; harvesting; humans; ice; immigration; juveniles; least squares; males; population dynamics; population size; pups; seals; summer; Antarctica; McMurdo Sound
Abstract:
... Population dynamics of Weddell seals in McMurdo Sound, Antarctica, were studied from 1970 to 1984 using mark—recapture estimation, aerial surveys, age structure and magnitude of harvests, and direct counts of pup production. Similar data from earlier studies were used to reconstruct the history of the population during the period of human presence after 1956. Jolly—Seber estimates of population si ...
... 61 Species new to the Admiralty Bay region are reported. Among them 51 are new to King George Island, 35 to the South Shetland archipelago, 15 to the Antarctic zone, and 6 to the Southern Hemisphere. A further 49 species were found at new localities. ...
... We report the finding of two species of Mantoniella from the Weddell Sen and Prydz Bay, Antarctica. As well as M. squamata, a cosmopolitan species, we describe M. antarctica sp. nov., the second species in this genus. M. antarctica is covered with two distinctive types of discoid scales. The flagella bear only the smaller of the scale types whereas the cell body has both types, the larger overlyin ...
... HILL, R. S., 1991. Tertiary Nothofagus (Fagaceae) macrofossils from Tasmania and Antarctica and their bearing on the evolution of the genus. Eight new species of Nothofagus are described from Tertiary deposits in Tasmania and West Antarctica, based on leaves and cupules. Several other species are re-examined. The new species include the first fossil species in the subgenera Brassopora and Nothofag ...
... Since October 1986 living benthic molluscs from the eastern Weddell Sea, Antarctica (Fig. 1) have been kept alive in aquaria. Special equipment and methods have been used to reduce disturbance and laboratory effects during the long-time rearing. Autecological investigations were carried out on behaviour, reproduction biology and growth of several polyplacophoran, gastropod and bivalve species. ...
... A pollen diagram from King George Island, South Shetland Islands, is presented; it is the first from the Antarctic region. A basal radiocarbon date indicates a calibrated age of 300 years or less. Pollen of one or both of the native vascular plants and many long-distance transported types, mainly Nothofagus, are present in all samples. A total of 37 long-distance transported pollen and spore types ...
... The challenge of how best to manage the Antarctic is no small task. The fragility and unenforceability of the existing legal arrangement, coupled with the uncertainty of commercial mineral/hydrocarbon extraction and the need to protect an extremely fragile ecosystem, adds up to a series of dilemmas of immense proportion. This paper argues that the best solution for the continent is to make it into ...
... We used electronic time depth recorders to examine diving patterns of Adelie Penguins (Pygoscelis adeliae) breeding near Palmer Station, Antarctica. Most hunting dives consisted of a rapid descent to depth, a period of bottom time at near—constant depth, and a rapid ascent to the surface. Most hunting activity occurred in bouts of consecutive dives to similar depths. Adelies foraged at depths betw ...
... The continent of Antarctica holds immense value as a wilderness area and a repository of scientific knowledge. This report maintains that the Protocol to the Antarctic Treaty on Environmental Protection, signed in 1991, is a positive first step in ensuring that Antarctica preserves its status as a global scientific laboratory, wildlife refuge, and arena for international cooperation. ...
Chlorellales; Golgi apparatus; electron microscopy; reproduction; ultrastructure; vegetative cells; Antarctica; Japan
Abstract:
... Lobosphaera reniformis (Wat.) Kom. et Fott (=Chlorella reniformis Wat.) so far known only from Japan, and Papua Island, was for the first time found in Antarctica (King George Island, South Shetland Islands). In laboratory cultures a complete life cycle was obtained, and most of its stages were followed by the electron microscopy. Reproduction is by morphologically different autospores. In some la ...
... Freezing and thawing of the endemic moss species Grimmia antarctic) Card. caused photoinhibition. When snow cover was removed from moss in the field, resulting in exposure to fluctuating temperatures and light conditions, photoinhibition, measured as a reduction in the ratio of variable to maximum chlorophyll alpha fluorescence (Fv/Fm), was observed. The extent of photoinhibition was highly variab ...
... 1. The influence of inorganic nitrogen and phosphorus enrichment on phytoplankton photosynthesis was investigated in Lakes Bonney (east and west lobes), Hoare, Fryxell and Vanda, which lie in the ablation valleys adjacent to McMurdo Sound, Antarctica. Bioassay experiments were conducted during the austral summer on phytoplankton populations just beneath the permanent ice cover in all lakes and on ...
... Tolerance of antarctic moss to freezing and thawing stress was investigated using chlorophyll a fluorescence. Freezing in darkness caused reductions in Fv/Fm (ratio of variable to maximum fluorescence) and Fo (initial fluorescence) that were reversible upon thawing. Reductions in Fv/Fm and Fo during freezing in darkness indicate a reduction in the potential efficiency of photosystem II that may be ...
... Wood from an in situ permineralized forest from the Middle Triassic of Gordon Valley (Queen Alexandra Range, central Transantarctic Mountains) in Antarctica is described as a new taxon, Approximately 100 trunks in growth position are present at the site; they range from 13-61 cm in diameter and suggest that some of the trees were up to 20 m tall, Pits in the radial walls of the tracheids are of th ...
Umbilicaria; carbon dioxide; freezing; gas exchange; ice nucleation; lichens; photosynthesis; primary productivity; scanning electron microscopy; snow; temperature; water content; water potential; water uptake; Antarctica
Abstract:
... Photosynthetic activity and structural changes at subzero temperatures were monitored in the foliose lichen Umbilicaria aprina Nyl. from continental Antarctica. Carbon dioxide gas exchange measurements revealed that net photosynthesis and dark respiration occurred at subzero temperatures regardless of whether a lichen thallus saturated with liquid water was exposed to subzero temperatures, or if a ...
Crustacea; Polychaeta; animals; anthropogenic activities; benthic organisms; community structure; field experimentation; freezing; habitats; ice; icebergs; latitude; life history; marine sediments; pollution control; polychlorinated biphenyls; species diversity; weight-of-evidence; Antarctic region; Antarctica; McMurdo Sound
Abstract:
... Sampling and field experiments were conducted from 1975 to 1990 to test how the structure of marine benthic communities around McMurdo Station, Antarctica varied with levels of anthropogenic contaminants in marine sediments. The structure of communities (e.g., infauna density, species composition, and life history characteristics) in contaminated and uncontaminated areas were compared with the str ...
shoots; plant morphology; biomass; leaves; water content; turgor; weight; mosses and liverworts; Antarctica
Abstract:
... The dependence of shoot growth and growth form on water availability was studied experimentally in six species of maritime Antarctic moss. Under all conditions the largest growth increments were observed in the hydric species Brachythecium austro‐salebrosum and Drepanocladus uncinatus. The xeric Andreaea depressinervis grew the least. Lateral shoot production varied within and between species. Ove ...
cold zones; algae; global warming; community ecology; Cyanobacteria; ozone depletion; Antarctica
Abstract:
... There is increasing evidence of climate change in Antarctica, especially elevated temperature and ultraviolet B (UVB) flux within the ozone "hole." Its origins are debatable, but the effects on ice recession, water availability, and summer growth conditions are demonstrable. Light-dependent, temperature-sensitive, fast-growing organisms respond to these physical and biogeographical changes. Microa ...
interspecific variation; mathematical models; equations; gas exchange; air temperature; light intensity; mosses and liverworts; seasonal variation; water content; photosynthesis; chlorophyll; habitats; Antarctica
Abstract:
... Carbon fixation under controlled conditions was measured in three mosses from the maritime Antarctic using an infra-red gas analysis system. Gas exchange parameters were determined during each season in 1993 and 1994 using the Arrhenius equation and a hyperbolic tangent function applied to respiration and photosynthesis, respectively. Environmental data was collected in 1994 for comparison. All se ...
wounds and injuries; Pygoscelis; mortality; necropsy; Antarctica
Abstract:
... The postmortem findings of an adult male Adelie penguin found at Magnetic Island, East Antarctica, demonstrating a premortem wound in addition to those consistent with an attack and scavenging by south polar skuas, are described. Other causes of mortality are discussed. ...
... Numerous permineralized axes of Middle Triassic age from Fremouw Peak, Antarctica show evidence of mechanical wounding and wound responses. These consist of both elongate and triangular-shaped scars. Some scars can be detected beneath subsequent secondary xylem, indicating that wounding occurred early in stem development. In other stems, scars remained open suggesting late wounding and the permane ...
Tribonematales; chloroplasts; light microscopy; nuclear membrane; salinity; salt tolerance; transmission electron microscopy; Antarctic region; Antarctica; Europe; New Zealand
Abstract:
... Seventeen strains of Xanthonema Silva (Tribonematales, Xanthophyceae) are examined by light microscopy and transmission electron microscopy, and their salinity tolerance is investigated. Ten strains are from Antarctica where the genus is poorly known. These strains are compared with two strains from New Zealand and five from Europe, including the only existing authentic strains of three species. S ...
... Humic acids play an important role in the solubility, mobility and accumulation of trace metals in marine environment. Nine sediment samples collected in Terranova Bay, Antarctica, have been treated in order to extract the metal—humic acid complexes. The concentration of humic acids was measured with a spectrophotometric method while five trace metals, Cr, Cu, Mn, Ni and Zn were determined by mean ...
... During the middle of the 1992 austral winter in the northern Windmill Islands, continental Antarctica, a highly unusual climatic event occurred in which the air temperature exceeded 0°C for some 60 h, at the end of which there was a significant rain shower before the ambient temperature returned to subzero conditions. This event caused most of the snow cover to melt and refreeze as clear ice. Lich ...
... Physiological and developmental responses during and following long-term exposure to darkness were investigated in the Antarctic red algae Palmaria decipiens (Reinsch) Ricker and Iridaea cordata (Turner) Bory. Thalli were kept in darkness for a period of 6 mo, simulating winter sea ice cover. Subsequently, they were grown illuminated under seasonally fluctuating Antarctic daylengths. During darkne ...
interspecific variation; solar radiation; air temperature; photoinhibition; light intensity; carbon; Bryopsida; habitats; Antarctica
Abstract:
... Rates of carbon flux in 14 species of Antarctic bryophytes were measured under controlled conditions using an infra‐red gas analysis system. The results were used to produce estimates of mode! parameters for respiration and photosynthesis. The relationships between respiration, photosynthesis, irradiance and temperature followed standard patterns. Temperature optima for gross and net photosynthesi ...
G.M. MARION; G.H.R. HENRY; D.W. FRECKMAN; J. JOHNSTONE; G. JONES; M.H. JONES; E. LÉVESQUE; U. MOLAU; P. MØLGAARD; A.N. PARSONS; J. SVOBODA; R.A. VIRGINIA
air temperature; cooling; ecosystems; growing season; heat; plant growth; snow; snowmelt; soil temperature; vegetation; wind speed; Antarctica; Arctic region
Abstract:
... Passive open‐top devices have been proposed as a method to experimentally increase temperature in high‐latitude ecosystems. There is, however, little documentation on the efficacy of these devices. This paper examines the performance of four open‐top chambers for altering temperature at six sites in the Arctic and Antarctica. Most of the heating effect was due to daytime warming above ambient; occ ...
... Eight pedons representing three climatic zones and parent materials ranging from Holocene to Pliocene were characterized from the Dry Valleys region of Antarctica. All of the soils contain abundant water-soluble salts, including NaCl in coastal regions, NaNO₃ along the polar plateau, and Na₂SO₄ in intermediate areas. The salts originate primarily from atmospheric deposition and accumulate linearly ...
... In Antarctica, ornithogenic soils from penguin guano play an important role in nutrient cycles in the ecosystem. Soil organic matter (SOM) degradation and translocation are the main determinants of these dynamics, of which podzolization is probably one, in ornithogenic soil. The purpose of this study is to describe the SOM in the older ornithogenic soils of Coastal Continental Antarctica in order ...
... Two new palynomorph taxa are described, and several existing taxa are discussed from the Upper Jurassic‐Lower Cretaceous Byers Group of Livingston and Snow islands, South Shetland Islands, Antarctic Peninsula. Oligosphaeridium byersense sp. nov., a dinoflagellate cyst species, is found in the Valanginian interval of the Byers Group. Globorotundata acrita gen. et sp. nov., apalynomorph of unknown a ...
Jasus; Panulirus; evolution; genetic variation; habitats; islands; larvae; lobsters; monsoon season; runoff; tectonics; Antarctic region; Antarctica; Australia; India; Indian Ocean; New Zealand; South Africa; Tasman Sea
Abstract:
... Jasus is at least as old as early Miocene (20 Ma). Genetic differentiation between J. verreauxi in Australia and New Zealand indicates larval isolation across the northern Tasman Sea following a northward retreat of a strong south-flowing warm current. After South Africa and Australia separated from Antarctica, stocks of the temperate J. lalandii subgroup of three species became genetically isolat ...
... Exposure to extremes of temperatures cause stresses which are sometimes lethal to living cells. Microorganisms in nature, however, are extremely diverse and some of them can live happily in the freezing cold of Antarctica. Among the cold adapted psychrotrophs and psychrophiles, the psychrotrophic bacteria are the predominant forms in the continental Antarctica. In spite of living in permanently co ...
carbon dioxide; fluorescence; gas exchange; air temperature; light intensity; mosses and liverworts; electron transfer; field experimentation; photosynthesis; chlorophyll; lichens; Antarctica
Abstract:
... The relationship between CO2 exchange and relative electron-transport rate through photosystem II (ETR, measured using chlorophyll a fluorescence) was determined for a moss and a green algal lichen, photobiont probably Trebouxia sp., in the field in Antarctica. Net photosynthesis (NP) and dark respiration (DR) were measured over temperatures from zero to 25 degrees C and gross photosynthesis (GP) ...
... McMurdo Station is the largest research station in Antarctica, with a population that ranges each year from 250 to 1200 people. Because of its size and 40-year history of use, a number of locations around the station have become contaminated with wastes. Soils and sediments in these areas have been shown to contain elevated levels of petroleum-related products, PCBs, other organics, and metals. Wh ...
... Seasonally changing photophysiological and biochemical characteristics of sea ice microalgae are interpreted with respect to light availability and measurements of nutrient concentration made at high vertical resolution (12.5 cm) during a dense bloom in the platelet ice layer of McMurdo Sound during a 6-week study in austral spring of 1989. Platelet ice algae remained highly shade adapted througho ...
... Oil spills occur in the Antarctic when fuel oils such as JP8 jet fuel are moved or stored. Hydrocarbons, both n-alkanes and aromatic compounds, have been detected in oil-contaminated soils of the Ross Dependency. In such areas hydrocarbon-degrading microbes, if naturally occurring, could be used for clean-up. Soil samples from oil-impacted and control sites were analysed for hydrocarbon-degrading ...
... A comprehensive diatom stratigraphy is used to calculate a palaeosalinity history for an Antarctic lake via an established diatom-salinity transfer function for the Vestfold Hills, Antarctica. A sediment core taken from Ace Lake in 1995 shows three distinct changes in diatom assemblage constituents: initial benthic hyposaline – freshwater taxa are replaced by marine planktonic and sea-ice taxa wit ...
... The genus Muelleria (Frenguelli) Frenguelli is considered in taxonomic, systematic, and biogeographic contexts. Muelleria is a small genus composed of 15 known species. In the present report, four species are newly described (M. algida S.A. Spaulding et Kociolek sp. nov., M. luculenta S.A. Spaulding et Kociolek sp. nov., M. variolata S.A. Spaulding et Kociolek sp. nov., and M. varipunctata S.A. Sp ...
... Aspects of the ecology of South Polar Skuas Catharacta maccormicki were investigated at Hop Island, Rauer Group, East Antarctica between December 1990 and February 1991. Data were obtained from pairs across the island generally for comparison with skuas (fringe-dwellers) nesting away from Adélie Penguin Pygoscelis adeliae colonies. While most defended territories included colonies of Adélie Pengui ...
... A continuous, ¹⁴C dated palaeoenvironmental (4000-year) proxy from the Antarctic Peninsula glacial marine record demonstrates pronounced cycles of elevated palaeoproductivity (warm events) that recur every 200 years. Superimposed upon this are longer-term reductions in palaeoproductivity (cooling events) that correspond with the‘Little Ice Age’ and an event at ~2500 radiocarbon years BP. Compariso ...
Bryum argenteum; air temperature; carbon; freezing point; habitats; hydrology; lawns and turf; mosses and liverworts; photosynthesis; shoots; soil; solar radiation; summer; water content; Antarctica
Abstract:
... Bryum argenteum, B. pseudotriquetrum and Ceratodon purpureus are the predominant mosses in Victoria Land, continental Antarctica. All have cosmopolitan distributions and are widespread throughout Antarctica with wide ecological amplitudes resulting in considerable morphological variation. They are well adapted to tolerate the physiological stresses imposed by the severe environment. This study inv ...
... Thermoluminescence ages from a longitudinal dunefield in tropical northern Australia suggest that complete dune activation occurred here either continuously or sporadically between approximately 8.2 ka and 5.9 ka. This period, in Australia, is normally ascribed to one of increasingly warm and wet conditions towards the Holocene Climatic Optimum. However, elsewhere, this time (~8 ka) coincides with ...
... The mannanase (endo-beta-1,4-mannanase; E.C. 3.2.1.78) and xylanase (endo-beta-1,4-xylanase; E.C. 3.2.1.8) activity of five microfungal isolates from Antarctica were characterized at different temperatures and pH. In general, the hemicellulase activity of the antarctic strains occurred at least 10 degrees C and as much as 30 degrees C lower than that of a mesophilic reference strain. At 0 degrees ...
... Statistical analyses of diatom assemblages from radiocarbon-dated sediment cores were used to reconstruct changing palaeoceanographic conditions in the western and west-central Ross Sea, Antarctica, from. c.12 ¹⁴C kyr BP to the present. Data from three Kasten cores support a north-to-south time-transgressive glacial/interglacial transition. Assemblages at the base of each core suggest that glacial ...
... The major influences on the salinity and water level of an Antarctic lake are parameterized and a palaeohydrological model linking the palaeosalinity of an Antarctic lake to the palaeohydrology of the lake is developed. Climatic change in this lake is recorded in the evaporative loss trend reconstructed from water level and lakewater salinity estimates. A decrease in salinity betweeñ700 and 200 ye ...
... Microfungi from Antarctica were grown at 10 °C, 21 °C, 28 °C and 37 °C on a series of plates each containing a single carbon source and designed to indicate the secretion of particular hydrolytic enzymes. Colony radius and hydrolytic activity were measured and a relative activity index (RA) established. In general, effective hydrolysis occurred at mesophilic temperatures. Some enzymes, especially ...
... The bioavailability of fluoride from krill exoskeleton and the effect of additional calcium on the bioavailability of fluoride from krill paste were evaluated using young rats. Fluoride from the exoskeleton showed a high apparent absorption of 80%. Approximately 3.6% of this fluoride was deposited in the femur, and 44% in the rest of the carcass. The presence of 1.5% and 2.5% calcium (CaCO3) in th ...
... The diet of the Cape Petrel was investigated in two localities of South Shetland Islands, Antarctica, over the period January—February 1996. Stomach contents of adults obtained by flushing and regurgitates of chicks were sampled during the chick-rearing period. During the whole sampling period, euphausiids represented the predominant prey in terms of frequency of occurrence, mass and number at Fil ...
... Stratospheric ozone depletion by anthropogenic chlorofluorocarbons has lead to increases in ultraviolet-B radiation (UV-B; 280-320 nm) along the Antarctic Peninsula during the austral spring. We manipulated UV-B levels around plants of Antarctic hair grass (Deschampsia antarctica; Poaceae) and Antarctic pearlwort (Colobanthus quitensis; Caryophyllaceae) for one field season near Palmer Station alo ...