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Number of results: 67
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Abstract

Influence exerted by various concentrations (0.01 to 50 ppm) of some chlorinated hydrocarbons (Aroclor 1254, Aroclor 1242, pp'DDE, pp'DDT and Lindane (ɣ НСН)) upon the photosynthetic assimilation of 14C02 in Antarctic marine diatom assemblage dominated by Corethron criophilum and some species of Nitzschia (Fragilariopsis group) has been investigated. The photosynthesis was fully inhibited by Lindane (ɣ HCH) in all applied concentrations To smaller extent the photosynthetic process was inhibited in turn by Aroclor 1242, pp'DDE and pp'DDT successively. Aroclor 1254 proved to be the least toxic. The possibility of the decrease of the primary production of the Antarctic diatoms caused by the chlorinated hydrocarbons was discussed.
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Abstract

Experiments have been carried out on the influence exerted by Aroclor 1254 upon the photosynthetic production of organic 14C by an assemblage of marine Antarctic diatoms (Thalassiosira sp. 48%, Nitzschia sp. 21%, Chaetoceros sp. 15% and Corethron iriophilum 10%). Samples of various numbers of cells per cm3 of water have been used. Incorporation of 14C02 by the diatoms proved to be proportional to the increased number of cells in the sample only at the lowest levels of concentration in per cm3. Further increase of the level of 14C in diatoms has not been found as number of cells in the sample kept growing. Calculation of brutto photosynthesis has indicated that low concentration of Aroclor 1254 (0,01 to 1 ppm) may stimulate the photosynthetic incorporation of carbon, yet the photosynthetic release of carbon from cells within the photorespiratory process is stimulated to a higher degree. High concentration of Aroclor (1 to 50 ppm) inhibit the brutto assimilation, yet the release of carbon during the photorespiratory process is inhibited to a higher degree. A hypothesis is being considered implying that the relation between the intensity of photosynthesis and intensity of photorespiration may vary according to the rate of concentration of Aroclor.
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Abstract

Antarctic krill carbohydrate content was followed during 1983—84 Eighth Polish Antarctic Expedition. The Admiralty Bay (King George Island) was th area of study. The following average values of three estimated fractions were obtained: 3.77 +- 1.51%, 0.47 +- 0.34% and 3.30 +- 1.33% for total, TCA-soluble and TCA-insoluble carbohydrates, respectively. Percentage contribution of the estimated fractions to dry weight varied seasonally (1.48—7.41%, 0.15—1.83%, and 1.28—6.28%, respectively). The carbohydrate content showed a clearcut cycle of changes over the calender year, with a minimum in autumn-winter and a maximum in spring-summer.
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Abstract

ll was proved that the activity of basic proteinases (pH 8.3) and acid proteinases (pH 4.0) of the Antarctic krill increases exponentially in spring-summer season (September-December); the activity of the first ones is 6 times higher and increases more rapidly. The positive relation between the proteolytic activity and the degree of gut filling of krill was also evidenced. The lack of high activity of acid proteinases in early spring does not support the suggestions of Ikeda and Dixon (1982) that during Antarctic winter krill takes energy from the autoproteolysis of own body proteins.
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Abstract

The period of nesting development of Wilson's storm petrels (approx. 60 days) could be divided into three stages: first from hatching to 8th—10th day of development; second, from 10th to approx. 25th day and third from 25th day until nestlings leave the nests. During the first stage hemoglobin concentration in the blood decreases significantly while total surface of erythrocytes and the hematocrit increases. At that time nestlings do not grow very fast. In the second stage of development the values of all studied parameters do not change, while the growth of body weight is very intensive. The last stage is characterized by significantly reduced growth rate accompanied by important changes of all hematological parameters responsible for the respiratory function of blood volume unit.
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Abstract

In colonies situated at the southern coast of King George Island the nesting areas of penguins of the genus Pygoscelis were investigated with respect to the protection of eggs and chicks against flooding. Relationships between the nesting strategy determined by the characteristics of breeding grounds, degree of colonization and breeding time, and the climatic conditions of zones in which majorities of particular species populations breed were presented. It was recorded, that interspecific differences in nesting strategy of pygoscelid penguins enable species which breed sympatrically to avoid competition for the nest-sites, and also seem to be responsible for various population dynamics of species in the maritime Antarctic.
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Abstract

This paper reports on eleven species of hepatics collected on King George Island, South Shetland Islands (6Г50'—62°15'S latitude and 57°30'—59 00'W longitude). A short account of the vegetation of this Antarctic island is provided and the role of liverworts in particular plant communities is discussed. Two species, Hygrolembidium ventrosum (Mitt.) Grolle and Scapania abcordata (Berggr.) S. Arnell are reported for the first time from the Antarctic botanical zone; the latter is recorded for the first time in the Southern Hemisphere and, additionally, this is the first record of the genus Scapania from Antarctica. A detailed description of the habitat of each taxon is given and distribution maps for the eleven species are provided. A key to the eleven species from King George Island is given, and a detailed taxonomic discussion is included for Cephaloziella varians (Gott.) Steph and Lophozia excisa (Dicks.) Dumort. The former is considered to be synonymous with the widespread Arctic species C. arctica Bryhn & Douin ex K. Müll.
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Abstract

Benthic gastropods (45 taxa) inhabiting 11 coastal areas of South-West Svalbard are listed. The dominant species are indicated; frequency of occurrence of various gastropods in different areas is discussed.
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Abstract

A short review of the history of the hepaticological exploration of Antarctica is given in the present paper. An annotated check list of all taxa of hepatics reported from within the Antarctic botanical zone, based on literature data and unpublished records, is included. Altogether 22 species of liverworts, excluding two taxa known only at generic level, representing 18 genera and 13 families, are known to occur in the Antarctic. All species of hepatics, except for Cephaloziella varians which is also known from Greater Antarctica, occur exclusively in the maritime Antarctic region. In the livewort flora of Antarctica, the southern temperate and subantarctic elements are predominant (72.7%) and the bipolar element is remarkably scarce, albeit the bipolar taxa belong to the most widespread and frequent of the impoverished Antarctic hepatic flora. Distribution patterns of all known Antarctic liverworts are briefly discussed and several floristic elements and subelements are recognized.
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Abstract

During marine ecological surveys conducted by Polish expeditions in South Spitsbergen area 14 fish species were collected. The length frequency, the diet and some other ecological informations are presented for the most common species.
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Abstract

Fluted ground moraine deposits in the forefield zones of the Blomli, Scott and Renard glaciers were investigated. It was found that the fluted moraine crests, especially the stone-rich ones, continue on the glacier front surface as cones or stony belts. The linear ablation forms, partly filled by the supraglacial sediment, are the extensions of the crests formed from the finer material. Thus, the opinion is expressed that the ribs and furrows at the top surface of the ground moraine are the result of the supraglacial material deposition and that they reflect the differentation of the ablation relief of the front surface of the recessing glacier. Till now the fluted relief origin was joined exclusively with the subglacial conditions and such forms were considered as the indicators of the glacier movement direction.
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Abstract

J. G. A. Forster, member of J. Cook's expedition towards South Pole, spent the majority of his life in Poland. In the years 1784—1787 he was professor of natural history at the Wilno University. Born near Gdańsk, he never lost the consciousness of his Polish citizenship. Forster's publications have enriched the culture and science of England. France, Germany, Poland and other countries.
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Abstract

Planktonie foraminifera of the genera Chiloguembelina Loeblich and Tappan. Globigerina d'Orbigny and Globorolalia Cushman are reported from glacio-marine sediments of the Low Head Member (Polonez Cove Formation, Oligocene) of King George Island (South Shetland Islands). West Antarctica. The foraminifer assemblage comprises two stratigraphically important species: Globigerina angiporoides Hornibrook and Chiloguembelina cubensis (Palmer), which indicate the Upper Eocene — Lower Oligocene age. Taking into account specific composition, this planktonie assemblage may tentatively be correlated with the Globigerina angiporoides Zone of New Zealand. Australia. South Pacific and South Atlantic, which belongs to the Lower Oligocene (see Jenkins 1985).
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Abstract

Over the South American sector of the Antarctic Ocean intensive cyclonal activity occurred in turn with meridional circulation, which was a more common feature of winter 1986 than it usually is. At the Arctowski Station strong temperature oscillations were observed during the austral winter from May to October. In the end of July the lowest temperature of this winter, — 32.3°C, was recorded. In the first half of the winter an easterly air flow prevailed and in the second part — the westerly one. Winds were strong and gusty. The highest speed reached 74 ms-1 . Snowfalls were abundant; depth of snow exceeded 100 cm.
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Abstract

The most popular field methods of measurements of raised marine beach altitudes used by geomorphologists are presented. Compared data from clisimeter routes, altimeter routes and from readings from a photogeological map and directly from air photos compose the profiles. Advantages and disavantages of each method are discussed.
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Abstract

About 1600 joint fractures were measured in tillites of the Upper Hecla Hoek Formation on the southern shore of Bellsund. Measurements were collected in 12 areas between the Renardbreen and Tjörndalen. Ray diagrams and contour diagrams of joint fractures, and contour diagrams of joint fractures after rotation to pre-folding position were made for each area. The preliminary analysis of diagrams indicates 2 conjugated joint sets: ca. 60°—120° and 0°—30°. This joint system is probably older than folding and was originated under ENE—WSW to NE—SW stress.
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Abstract

The dynamics of some features of arctic soils and their connection with air-water relations are presented. Investigations of 5 selected profiles were carried out in 1987. Considerable dynamics of moisture, redox potential (Eh) and oxygen diffusion rate (ODR) during the summer season were confirmed. Oscillations of these features in individual profiles and sometimes in their horizons were distinguished.
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Abstract

The paper deals with Recent and relic phosphatic soils of ornithogenic origin which occur in ice free oasis of the maritime Antarctic Zone (Antarctic Peninsula and King George Island regions). These soils form on rocky and clay weathering covers within and around of penguin rookeries. Their morphology strongly depends on penological character of a substrate and climatic differentiation of a region. They are built of a surface layer of guano and underlying zone of a phosphatized rock. Except organic matter and unstable urates, the guano contains calcium phosphates (fluorapatite somtimes brushite) and magnesium-amonium phosphate (struvite). The phosphatized zone consists of phosphatic- silicate clays in which occur diversified aluminium-iron phosphates bearing potassium and ammonium ions (leucophosphite, minyulite, taranakite, amorphous aluminium phosphate). The guano layer is strongly reduced by erosion and weathering in ornithogenic relic soils left by penguins in areas abandoned by them during Holocene. Formation of a humus horizon of a plant origin may be observed under a vegetation cover in the relic soils. Clays of the phosphatized zone in these areas are transformed in the processes of chemical and mechanical weathering, by mass movements and frost processes.
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Abstract

The glacial and glacio-marine sediments of the Oligocene Polonez Cove and Early Miocene Cape Melville Formations on King George Island (South Shetland Islands, West Antarctica) yield numerous erratic boulders of limestone, in particular archaeocyathan-algal boundstone, oolite, onkolite, and biomicrite. Some of these boulders are fossiliferous and contain archaeocyathans, sponges, inarticulate brachiopods, monoplacophorans, gastropods, hyolithids, trilobites, ostracodes and such enigmatic fossils as: Chancelloria, Coleolella. Dailyatia. Halkieria. Hadimopanella. Hyolithellus. "Lenastella", Mongolitubulus and Torellella. The small shelly fauna appears to be Early Cambrian (Botomian) in age. The boulders of fossiliferous limestones resemble the rocks of the Shackleton Limestone unit in the central Transantarctic Mts. The lithological composition of the boulder assemblage brought to King George Island during the Tertiary glaciations suggests that the Cambrian outcrops around the Weddell Sea are the source of the erratics. The Antarctic Lower Cambrian fauna resembles its analogues in Australia and Asia.
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Abstract

The paper presents an overview of lithostratigraphy and radiochronological and biochronological data for the Tertiary volcanic and sedimentary successions of King George Island, South Shetland Islands (West Antarctica). Special stress was laid on dating fossiliferous terrestrial and marine strata and glacial and glacio-marine deposits of Tertiary age. for which King George Island offers the most complete and so-far best documented standard in the Antarctic Peninsula sector of West Antarctica.
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Abstract

The algal microfossil Bolboforma reticulata Daniels and Spiegler is recorded from the Oligocene-Miocene glacio-marine sediments of King George Island, South Shetland Islands, Antarctica. The record extends the geographic extent of the species to Antarctica.
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Abstract

Rocks of the Legoupil Formation in the Cape Legoupil area were folded about a N70E oriented axis. Later these rocks were affected only by brittle deformation which occurred in four stages: (1) jointing — set I, (2) dyking, (3) faulting and, (4) jointing — set II. Both, folding and subsequent brittle deformation, are hardly compatible with the Mesozoic-Cenozoic eastward subduction of the ancient Pacific ocean crust.
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