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Słowa kluczowe Antarctica South Shetlands fungi

Abstrakt

Mycological analyses of the air and food remnants in heated and non-heated rooms of the H. Arctowski Polar Station were carried out. In the material 23 fungi strains were found representing 10 species of the classes Ascomycetes, Zygomycetes and Deuteromycetes.
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Bowseria arctowskii gen. et sp. nov., a new organic-walled monothalamous (single-chamber) foraminiferan is described from samples collected in Admiralty Bay (King George Island, West Antarctica) at 100- 200 m water-depth (mwd). The species is characterized by a large (1- 2 mm) elongate theca with a single terminal aperture. Molecular phylogenetic analyses, based on partial small subunit rDNA sequences, indicate that the new species belong to a clade of single-chambered foraminifers that branch as a sister group to the multi-chambered textulariids and rotaliids. The most closely related to the new species is an undetermined allogromiid from under the Ross Ice Shelf.
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The paper presents a list of over 100 amphipod taxa hitherto recorded in the Admiralty Bay, South Shetlands (Tab. 1). In Tab. 2 the distributional patterns of Amphipoda in upper and middle sublittoral (depth 5-150 m) of the Admiralty Bay are given. Notes on the taxonomy of some taxa are presented.
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Net of temperature, salinity and dissolved oxygen content measurements were made in situ at 24 stations in Admiralty Bay with the use of automatic analyzer Martek MK IV. Results proved a presence of two water masses located horizontally one over the other, with the boundary at depth of 15—35 m. The main, lower mass consists of homogenous waters inflowing from the Bransfield Strait. The upper, thin and much differentiated layer is formed through interaction of the main underlying water mass with meltwaters from glaciers and sea ice. It is probably formed along the whole archipelago and carried by surface currents into the bay where it is subjected to further modifications. Local salinity and temperature extremes are associated with glacier water runoff; local dissolved oxygen maxima seem to be connected with phytoplankton distribution. Strong currents occurring in te bay due to water circulation may cause local, short term and sometimes considerable fluctuations in values of parameters recorded at individual stations.
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During the austral summer of 2002/2003 the author collected 38 marine and/or glacio-marine sediment samples from Admiralty Bay on King George Island (South Shetland Islands, West Antarctica). Recent “living” (Rose Bengal stained) and “dead” (subfossil) benthic foraminifera represented by 105 species belonging to 65 genera are recognized in samples from water depths of up to 520 m. They show large spatial variability. Four distinctive foraminiferal zones within the fjord of Admiralty Bay were recognized and analyzed in terms of environmental conditions. The zones are: restricted coves, open inlets, intermediate-, and deep-waters. The major environmental factors, which dictate foraminiferal distribution, are closely related to bathymetry and distance to open sea. Sediment composition and chlorophyll content appear to have minor influence on foraminiferal communities. Most diverse, deep-water faunas dominate water-depths below 200 m , which seems to be the lowest limit of atmospheric and meltwater influence. In waters shallower than 200 m , environmental features, affecting distribution of various benthic foraminiferal assemblages, appear to be sedimentation rate and hydrographic isolation. The results of this study gives promise to use the Admiralty Bay foraminiferal distribution pattern as a paleoenvironmental tool for shallow- to intermediate-water Quaternary marine research in fjord settings of the South Shetland Islands.
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During the late 2007 austral summer, 20 sediment samples were collected in Admiralty Bay (King George Island, South Shetlands, West Antarctica) from 8 down to 254 m water-depth (mwd). The samples yielded abundant assemblage of monothalamous benthic foraminifera, belonging to at least 40 morphospecies. They constituted the first such collection from Antarctic Peninsula fjords and provided a new insight into this group’s diversity and distribution. Among organic-walled taxa, Psammophaga sp., Allogromia cf. crystallifera, and three morphotypes of Gloiogullmia were especially abundant. Agglutinated forms were dominated by Hippocrepinella hirudinea, Psammosphaera spp., Lagenammina spp., and various mudballs. Although, the majority of the morphotypes were known from other high-latitude locations, some were reported for the first time. Our quantitative data (>125 µm) showed the greatest differences between monothalamous foraminifera assemblages at shallowest water depths above 50 mwd. The deepest assemblages from between 179 and 254 mwd, were most similar, suggesting uniform near-bottom conditions at ~200 mwd throughout the Admiralty Bay.
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This paper presents a unique case study and methodology for measurements of the bedload transport in the two, newly created troughs at the forefield of the Baranowski Glacier: Fosa and Siodło creeks. The weather conditions and the granulometric analysis are presented and discussed briefly. Rating curves for the Fosa and Siodło creeks are presented for the first time for this region. Changes of the bedload transport as well as water discharge and water velocity at both creeks are investigated. The hysteresis for the relationships between rate of bedload transport and water discharges were identified showing that for both creeks for the higher water levels a figure of eight loop may be easily recognized. Moreover, a new method for the calculation of bedload transport rate, based on the weighted arithmetic mean instead of the arithmetic mean, is proposed.
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Eleven species of cumaceans were found in 105 samples collected in Admiralty Bay (King George Island) in the summers of 1984/85 and 1985/86, from 20 to 500 m depth range. Four cumacean assemblages were distinguished using the multivariate analysis. They were characterized by the dominance of one or two species often with low density values. Two assemblages were found in open waters of Admiralty Bay. The first inhabited on sandy−clay−silt and silty−clay−sand bottom deposits in the depth range from 140 to 330 m, with Campylaspis maculata (1.6 ± 2.1 ind./0.1m 2 ; F = 72.4%) and Leucon sp. (1.4 ± 1.6 ind./0.1m 2 ; F = 68.9%) as key species. The second assemblage was found in the depth range from 50 to 120 m with silty−sand sediments, and it was characterized by the presence of Vauthompsonia inermis (6.5 ± 6.6 ind./0.1m 2 ; F = 92.0%). A third assemblage was found in shallow waters influenced by glaciers in the bottom area of Ezcurra Inlet. It was characterized by sandy−clay−silt sediments and the presence of Eudorella splendida (14.6 ± 9.4 ind./0.1m 2 ; F = 100.0%) as a core species. The last assemblage was found in the shallow sublittoral (50–100 m) of Ezcurra Inlet and the central basin, with Diastylis anderssoni armata (1.5 ± 1.1 ind./0.1m 2 ; F = 85.7%) and Diastylopsis goekei (1.1 ± 1.0 ind./0.1m 2 ; F = 71.4%) as the most frequent and abundant species. V. inermis is considered a eurytopic species with high frequency in the whole material, and was present in all four distinguished assemblages. E. splendida and D. goekei were also recorded in each of the assemblages, but their total frequency was lower.
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New echinoid material from the Oligocene Chlamys Ledge Member (uppermost part of the Polonez Cove Formation) on King George Island, West Antarctica, includes the “regular” echinoid Caenopedina aleksandrabitnerae sp. n. and poorly preserved spatangoids, here tentatively identified as members of the genus Abatus . Caenopedina aleksandrabitnerae sp. n. is characterized by fully tuberculate genital plates, which sets it apart from most other species in the genus, by the uneven periproctal margin which indicates that periproctal plates were incorporated into the apical disc, and by moderately wide interambulacral plates with a height/width ratio of 1:3. Among the modern Caenopedina species it is closest to the Australian and New Zealand representatives, which is in contrast to previous reviews of Cenozoic Antarctic echinoid faunas that suggested limited relationship to the Australasian region. This is the first record of Caenopedina from Antarctica; it considerably extends its historical distribution to the south.
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Four new Antarctic holothuroid species are described for specimens from Admiralty Bay in King George Island. A new genus Dendrelasia O’Loughlin is erected for new cucumariid species Dendrelasia sicinski with dendrochirotid body form and elasipodid type spinous rod ossicles. Cucumariid Staurocucumis krzysztofi has bowl ossicles predominantly with marginal teeth. Provisionally−assigned thyonid Allothyone presleri has table ossicles with spires comprising predominantly four pillars. Molpadiid Molpadia magdae has a prickly cover of irregular table ossicle spires and fusiform table discs in both body wall and tail. Staurocucumis liouvillei (Vaney) is a “species complex”.
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Here we report a photo−documented record of a barn swallow ( Hirundo rustica ) from the South Shetland Islands. We also review previous records of passerine vagrants in the Antarctic (south of the Antarctic Convergence Zone). This barn swallow is the first re− corded member of the Hirundinidae family on King George Island and is only the second passerine recorded in the South Shetland Islands. This sighting, along with previous records of austral negrito and austral trush represent the southernmost sightings of any passerine bird anywhere in the world.
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Long term changes (46 years) in the a bundance of pygoscelid penguins breeding populations and nests distribution in the Lions Rump (King George Island) colony were investigated in three time intervals, according to previously published two censuses and one original study conducted in 2010. At that time a detailed colony map based on the GIS system was made. Results of this study showed different trends for each investigated species. In the last three decades Adélie penguin breeding populations showed strong declining tendencies (69.61%). In contrast, the population of gentoo penguins represents the reverse trend, increasing 171.85% over the same period. Observed changes in both penguin population sizes are reflected in the different spatial and geographic distribution of their nests. The population changes observed at the Lions Rump colony are consistent with the relevant pygoscelid penguin tendencies in the western Antarctic Peninsula region. Breeding penguin population dynamics at Lions Rump area with a minimal disturbance by human activity may well illustrate a natural response of those birds to environmental changes in the Antarctic.
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In the material of nearly 2000 individuals of Asteroidea collected in Admiralty Bay, the largest bay of the South Shetlands, 36 species were determined, enriching the list of hitherto known asteroid species of this basin by 17 taxa. One of them, Peribolaster macleani, is recorded for the first time in Western Antarctic. The most frequent and abundant asteroids of Admiralty Bay were Odonlaster validus, Psilaster charcoti, Bathybiaster loripes obesus and Diplasterias brucei. The bathymetric and geographic distribution of all species are discussed.
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Properties of a snow cover in the vicinity of Arctowski Station, King George Island (West Antarctica) were studied in 1991. Variations of snow quality and physical transformations were analysed against changes of atmospheric parameters, basing on water equivalent index and repeatable examination of snow pits. Essential dependence of snow cover distribution and snow structure from local climatic features and terrain morphology was found. Thawing occurs in the whole mass of snow, with its contribution of both liquid and gas water phases.
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Temperature of superficial water in the Ezcurra Inlet was measured from March 1989 to February 1990, with a use of a mercurial thermometer with accuracy +0.1°C. Temperature was measured usually once a month at selected points. Influence of various factors on temperature of superficial water was preliminarily analysed. Basing on these results, temperature distribution in the mentioned area was determined. Mean yearly temperatures for each station, average space temperatures on measurement days and mean yearly temperatures for the whole area of the Ezcurra Inlet were calculated.
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In the Admiralty Bay 36 taxa of macroalgae were found. Among them the most common were: green alga Monostroma hariotti, red algae — Georgiella confluens, Iridaea cordata, Leptosarca simplex and Plocamium cartilagineum, and brown algae — Adenocystis utricularis, Ascoseira mirabilis, Desmarestia anceps, D. ligulata, D. menziesii and Himatothallus grandifolius. The bottom surface covered with macroalgae (in the orthogonal projection on the water mirror) amounts to 36,9 km2 i.e. 31% of the total surface of the bay. In the central part of the Admiralty Bay the macroalgae aggregations occupy 35% of the bottom surface and are most abundant in respect to the density, biomass, number of taxa (33) and diversity. There were distinguished 3 zones of vertical distribution of phytobenthos in the Admiralty Bay. I zone includes the macroalgae in epilittoral, littoral and sublittoral to the depth of 10 m. II and III zones are situated in sublittoral within the depths of 10 60 m and 60—90 m, respectively. Each zone is characterized by the occurrence of different aggregation of taxa. The bottom areas belong to I, II and III zone of macroalgae make 28%, 64% and 8% respectively in relation to the total surface of phytobenthos in the bay. Vertical range of the distinguished zones varies in different parts of the Bay in relation to the bottom character. Macroalgae occur down to the depth of 90 —100 m. The composition of the macroalgae flora evidences for its transitory character between the benthic subantarctic flora and that of the areas adjacent to the Antarctic continent.
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By means of the synthetic diagram method (Romaniszyn 1970) populations of benthic Polychaeta at the depth ranging from 15 to 250 m of the Admiralty Bay (South Shetland Islands) were analysed. During the summer season of 1979/80 three replicate subsamples were taken at 18 stations situated along 3 crosssections using the Van Veen grab of a catching area of 0.09 m2 ; 61 benthic taxa of Polychaeta were recorded in these samples. The characteristics of particular assemblages are presented together with their tendency to change as a result of substrate quality, depth and position in the study area. Considerable affinity between the fauna of Polychaeta in the shallowest part of the bay and the composition and structure of polychaete assemblages occurring at Arthur Harbor (Anvers Island), which were described by Richardson and Hedgpeth (1977) was recorded.
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A collection of 15 283 individuals of tanaidacean crustaceans was gathered by successive Polish Antarctic Expeditions in the years 1977-1993 in Admiralty Bay (King George Island, South Shetland Islands). Twelve species belonging to three families are identified in this study. The material is clearly dominated by Nototanais antarcticus (Hodgson, 1902); other common species were Nototanais dimorphus (Beddard, 1886) and Peraeospinosus sp. A. The highest density of tanaids was over 140 000 specimens m-2 , occuring on a muddy bottom in Herve Cove lagoon.
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Pinnipeds were monitored in Admiralty Bay between 1988 and 1992. No particular trends during this period were found, but seasonal changes in each are distinct. It is suggested that the phenology of pinnipeds and that of penguins ensures low competition for food between these groups.
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This paper reports the species of macromycetes collected on King George Island and Livingstone Island (South Shetlands). Brief notes on taxonomy and distribution of the species are added.
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Meteorological conditions at Arctowski Station during 2013–2017 were presented against the background of regional climate changes, especially air temperature decline. Air temperature, relative air humidity, air pressure, solar radiation, wind speed and direction, snow cover and precipitation were collected with an automatic weather station and manual measurements and were further analysed. The obtained results were compared with data from previous years and with data from other stations located on King George Island. Our observations confirm that the vicinity of Arctowski Station experienced a decrease in air temperature during summer, which supports the hypothesis of regional cooling.
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Mid-winter rapid rise of temperature in the vicinity of Arctowski Station, King George Island (West Antarctica) was studied in 1991. Depending on circumantarctic migration of cyclones, sudden drop in air pressure and foehn-like phenomenon intensified by local topography occurred. Two such events are described on May 13 and June 28, against meteorological conditions during autumn and winter. Extreme intensification of morphogenetic processes caused degradation of a snow cover, immense meltwater discharge, radical transformation of slopes, effective aeolian activity and dynamic modifications in a sea-shore zone.
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The environments of inlets, coves and lagoons varies widely. Climate warming has lead to retreat of glaciers directly entering the sea. In lagoons this is accompanied by exposure of an uncolonized substratum. Colonization processes in these lagoon appear to describe processes which have previously occurred in bays and fjords of glacial origin in the South Shetlands.
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Cumacean crustaceans found in 188 qualitative and quantitative samples of zoobenthos collected in Admiralty Bay (King George Island, South Shetlands) by successive Polish Antarctic Expeditions in the years 1977 — 1989 were studied. In over 3000 individuals of these crustaceans 12 taxa were recognized. Eudorella splendida clearly dominated the material. Other common species were Campylaspis maculata and Vaunthompsonia inermis. The highest cumacean density amounted to 2618 ind.m-2 . Clear differences were observed between cumacean faunas of small grain sediment (muddy Ezcurra Inlet) and of mixed, coarser sediments (central part of Admiralty Bay with sand, gravel and mud). The dominance of Eudorella splendida was strongly marked in shallow Ezcurra Inlet whereas in deeper central part of Admiralty Bay the cumacean fauna was much more diversifield.
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The frequency of wind occurrence at sectors each 30° as well as mean air temperature at particular wind direction were accounted for the warmest and the coldest year of the investigation period 1978—1987 at Polish Antarctic „Arctowski" Station. The effect of orography on wind direction and air temperature was determined. A great rate of dependence of air temperature and wind direction upon atmospheric circulation type was found. High air temperature at the winds from 300° and 330° directions is related both to the kind of air mass and foehn phenomena.
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