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Number of results: 273
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Abstract

Soils, having a well-developed sequence of A and Bw horizons, are widespread on the uplifted marine terrace 8- 12 m a.s.l. in the proximity of Nottinghambukta Bay . The present-day origin of these soils is however questionable, while similarly developed soils, but buried under the cover of the youngest till were found on a forefield of the Werenskiold Glacier. To quantify an intensity of the soil-forming process under present climate conditions of SW Spitsbergen , the chronosequence of soils developed from the Recent, up to 70 year-old moraines, was studied on the forefield of Werenskiold Glacier. Significant dissolution of CaCO3, decrease of pH, leaching of calcium and magnesium, increase of amorphous iron content, as well as an accumulation of organic matter and initial formation of aggregate soil structure were observed within the surface layer of recent till. The 70 year-long period of pedogenesis was, however, too short for a distinct morphological differentiation of the subsurface B horizon. It is concluded, that deep and structural Bw horizons of some surface and buried soils are relicts of a much longer period of relatively warm climate before the last transgression of glaciers.
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Abstract

104 specimens of notothenioid fishes of five species (Patagonotothen longipes, P. tessellata, Champsocephalus esox, Cottoperca trigloides and Patagonotothen brevicauda) caught at two sites in the Beagle Channel (Magellanic sub-region, sub-Antarctica) were examined for the presence of thorny-headed worms (Acanthocephala). Representatives of three fish species, Patagonotothen longipes, P. tessellata, and Champsocephalus esox, were infected. Fishes caught at the eastern mouth of the channel were infected with 180 echinorhynchids representing three species, Aspersentis johni (the most numerous species), Heterosentis heteracanthus, and Hypoechinorhynchus magellanicus, and only 12 cystacanths of four polymorphids, Andracantha baylisi, Corynosoma sp., Corynosoma beaglense, and Corynosoma evae. Patagonotothen longipes was the most highly infected in the eastern mouth of the channel (prevalence 85%, maximum intensity 26). Aspersentis johni was the dominant parasite species in this host (prevalence 85%, mean abundance 4.00, maximum intensity 18) and H. heteracanthus was the sub-dominant one (prevalence 50%, mean abundance 2.60, maximum intensity 25). The infections of C. esox were the most diverse (six parasite species - three echinorhynchids and three polymorphids). Fish caught near the city of Ushuaia were infected only with six cystacanths of C. evae (intensity one). Taking into account the whole sample, C. evae was the most abundant polymorphid, represented by 10 of 18 specimens found. Three species, H. heteracanthus, A. baylisi and C. evae, have been previously reported from the low western Antarctic (H. heteracanthus also from the Kerguelen sub-region of sub-Antarctic), remaining four species seem to be endemics of the Magellanic sub-region of sub-Antarctic.
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Abstract

The organodetritic, sandy limestones of the Treskelodden Formation (Late Gzhelian to Early Artinskian) investigated in outcrops at Treskelen Peninsula, Hyrnefjellet mount and Polakkfjellet mount of south Spitsbergen, contain rich foraminiferal assemblages. Fifty eight foraminiferal species of twenty three genera, including two new species (Hemigordius hyrnefjelleti sp. nov. and Midiella arctica sp. nov.) have been identified. Three foraminiferal zones have been defined, with ages of Late Asselian (Pseudofusulinella occidentalis), Sakmarian (Midiella ovata – Calcitornella heathi) and Early Artinskian (Hemigordius hyrnefjelleti – Midiella arctica). Sedimentary features and the biotic history of the studied succession records a Late Paleozoic cooling trend that stays in accordance with Pangaea’s shift to the north.
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Abstract

The organic carbon (OC)-rich, black shale succession of the Middle Triassic Bravaisberget Formation in Spitsbergen contains scattered dolomite-ankerite cement in coarser-grained beds and intervals. This cement shows growth-related compositional trend from non-ferroan dolomite (0–5 mol % FeCO3) through ferroan dolomite (5–10 mol % FeCO3) to ankerite (10–20 mol % FeCO3, up to 1.7 mol % MnCO3) that is manifested by zoned nature of composite carbonate crystals. The d13C (-7.3‰ to -1.8‰ VPDB) and d18O (-9.4‰ to -6.0‰ VPDB) values are typical for burial cements originated from mixed inorganic and organic carbonate sources. The dolomite-ankerite cement formed over a range of diagenetic and burial environments, from early post-sulphidic to early catagenic. It reflects evolution of intraformational, compaction-derived marine fluids that was affected by dissolution of biogenic carbonate, clay mineral and iron oxide transformations, and thermal decomposition of organic carbon (decarboxylation of organic acids, kerogen breakdown). These processes operated during Late Triassic and post-Triassic burial history over a temperature range from approx. 40°C to more than 100°C, and contributed to the final stage of cementation of the primary pore space of siltstone and sandstone beds and intervals in the OC-rich succession.
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Abstract

Although the Antarctic has avoided the worst effects of alien species, its future seems endangered due to increasing natural and man-made pressures. Rapid changes in three major environmental variables have occurred in the Antarctic region during the last decades. In the short term terrestrial biota are likely to benefit from reduced environmental stresses, but in the long run the colonization of the region by lower latitude species with greater competitive ability will become increasingly important and can lead to large-scale changes in biological composition and trophic complexity in some existing Antarctic terrestrial ecosystems. Moreover, the recent dynamic climate changes combined with human activities in the Antarctic region might modify the status of several alien species which have hitherto been considered transient or persistent and could, therefore, become naturalized and threaten the native communities on a larger scale than today, or influence the status of naturalized species.
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Abstract

Solar radiation reflectance was analysed to characterize Arctic ornithogenic tundra developing in the vicinity of large breeding colony of Brunnich‘s guillemots Uria lomvia and kittiwakes Rissa tridactyla at the foot of Gnĺlberget cliff (Hornsund, SW Spitsbergen). Radiometric method was found to be a useful tool for studying structure and functioning of plant formations. We measured reflectance of four wavelengths: 554 nm (YG), 655 nm (RED), 870 nm (NIR) and 1650 nm (SWIR) at 10 plots situated along the transect running from the colony to the sea. Moreover, data of plant community character, species quantitative composition as well as total biomass were collected to relate these parameters with the spectral values. The results showed that radiometric data characterized vegetation well enough to recognize the same plant communities on the basis of spectral reflectance as distinguished with traditional phytosociological methods.
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Abstract

Brachiopods from the Chlamys Ledge Member, uppermost part of the Polonez Cove Formation (Oligocene), of King George Island, West Antarctica are represented by the undeterminable Rhynchonellida, one short-looped terebratulide Liothyrella Thomson, and two long-looped terebratellidines: Rhizothyris Thomson and Terebratelloidea gen. et sp. indet. Liothyrella is a well known genus in the Cenozoic strata and Recent waters of the Southern Hemisphere, while Rhizothyris is noted for the second time in the Antarctic region. This is the first record of brachiopods from the Chlamys Ledge Member.
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Abstract

Formerly reported as maritime Antarctic Bacidia sp. A has been re-named here as B. chrysocolla Olech, Czarnota et Llop. Another new species, B. subcoprodes Olech et Czarnota, found in the continental and maritime Antarctic has also been described here. A placement of both taxa within Bacidia De Not. is probably tentative because they are not congeneric with the type of this genus, B. rosella (Pers.) De Not. Similarities to other Bacidia with Laurocerasi-brown hypothecium and mostly 3-septate ascospores are discussed.
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Abstract

The Blue Dyke and Jardine Peak are subvertical hypabyssal intrusions cutting a stratiform volcanic sequence in the Admiralty Bay area on King George Island (South Shetlands, Antarctica ). The rocks are porphyritic, crystal-rich basaltic andesites. Tiny zircon crystals were used for single grain SHRIMP U-Pb dating. The mean ages calculated for the zircon populations from both intrusions indicates Late Oligocene (Chattian) formations. Zircon grains from the Blue Dyke gave the mean age of 27.9±0.3 Ma, whereas those from the Jardine Peak are slightly younger displaying the mean age of 25.4 ± 0.4 Ma: a Late Oligocene (Chattian) crystallization age the inferred of both these intrusions. These are much younger than previous Eocene K-Ar and Ar-Ar ages for such rocks and suggest that formation of the King George Island intrusions can be related to tectonic processes that accompanied the opening of the Drake Passage.
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Abstract

Penguins (Aves: Sphenisciformes) hold much interest for many people, including (but not limited to) scientists. According to results of molecular studies, penguin history began in the Cretaceous, but the oldest bones assigned to these birds are Paleocene in age. The first fossil representative of Sphenisciformes formally described was Palaeeudyptes antarcticus, and this event took place 150 years ago. Since that time, several dozens of species have been erected, though not all of them have stood a test of time. The 21st century entered new dynamics into the paleontology of penguins, and (importantly) it concerned both the new material, and new theories. This paper summarizes what we currently know about extinct penguins and indirectly suggests the most promising areas for further research.
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Abstract

A large sample of more than 1500 individuals of scavenging Amphipoda from fur seal carcass was studied. Six species have been identified. The two most abundant species, Abyssorchomene plebs and Waldeckia obesa, are sublittoral, necrophagous amphipods that could attack the carcass when submerged in the sea. After stranding on the beach they became an attractive food source for birds eating not only the seal tissues but also the scavenging amphipods. The species composition of the present sample as well as earlier data on Antarctic tern stomach content and baited traps taken in the same area and at the same time agreed quite well. These observations confirm the expectation that Antarctic tern feeds on necrophagous amphipods picked out from carcasses stranding on the sea shore.
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Abstract

Since 1978 the retreat of Ecology Glacier in the vicinity of Henryk Arctowski Station has opened new ice-free areas for colonization by terrestrial organisms initiated by pioneer microbes. Samples were collected from the soil surface, at 0, 5 and 20 cm below surface close to glacier front, then stored at below -20°C . Total bacterial count (TC), estimated by epifluorescence microscopy, reached high values, of 1010 g-1 dry wt. Healthy looking bacterial cells of mean volume 0.0209 µm3 at 0 cm to 0.0292 µm3 at 20 cm made up from 7% at 0 cm , to 30% at 20 cm of total bacterial population. The number of colony forming units (CFU) accounted for only 0.02% of TC. Taxonomically they belonged to the a, b, g subdivisions of the proteobacteria and to the Cytophaga-Flavobacterium-Bacteroides (CFB) group. Morphophysiologically CFU bacteria were diverse, from Gram variable short coccal forms to very long rods or filaments. Randomly selected CFU colonies were characterized by low sugar assimilation and high esterase/lipase activity. Spore forming bacteria – absent from 0 and 5 cm , formed a small fraction of 175 cells g-1 dry wt at the 20 cm depth. Filamentous fungi were relatively abundant and represented mainly by oligotrophs.
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Abstract

The aim of this study was to assess the anisakid nematode distribution pattern in the fish collected from the South Shetland Islands . A total of 32 fish species were examined for the presence of nematodes in 1978, 1979, 1981 and 2007/2008. The fish were caught off the South Shetland Islands ( Elephant Island , Shishkov Island and in Admiralty Bay – King George Island ). Three genera of L3 larval nematodes were identified: Anisakis sp., Contracaecum spp. and Pseudoterranova decipiens. The infection level was higher on the shelf around the islands than in Admiralty Bay . This is explained by a higher abundance of the final hosts in the region. A comparison of the infection data from 1978/79 and 2007/2008 with data from 1994/96 (Palm et al. 1998, 2007) was done. The parameters of infection of Notothenia coriiceps and Lepidonotothen nudifrons by Pseudoterranova decipiens were decreasing within the 30 years period.
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Abstract

Although the terrestrial marginal zones of some glaciers on Spitsbergen are relatively well described, we are largely ignorant about the morphology of their submarine forefields. Initial reconnaissance of the forefields of the Aavatsmark and Dahl glaciers in the Kaffiøyra region and soundings made in that of the Hans Glacier (southern Spitsbergen ) indicate the occurrence of sea-floor push-moraines which can be as much as 3 m high. Their lateral separation is considered to denote annual recession rates. They appear to result from cyclical annual advances of ice-cliffs during winters when the deposits are risen up at the contact of the ice with the sea-floor. The development of the major forms may be related to surge. There is some evidence that certain elements in the sea-bed morphology date from the Little Ice Age (LIA).
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Abstract

In the framework of the 4th International Polar Year Panel “Plate Tectonics and Polar Gateways” the international project “The Dynamic Continental Margin Between the Mid-Atlantic-Ridge System (Mohns Ridge, Knipovich Ridge) and the Bear Island Region” was undertaken in 2007-2008. As a part of this project a new three-component seismic broadband station was installed in September 2007 in the area of the Polish Polar Station Hornsund in Southern Spitsbergen . The new HSPB station has the coordinates: Φ = 77.0019°N, λ = 15.5332°E, H = 11 m a.s.l. During the first years of operation a number of good quality teleseismic events were recorded. This gives the opportunity for a first determination of crustal and mantle structure beneath the station by using receiver function (RF) and SKS splitting techniques. The Moho depth determined using RF is about 32 km beneath HSPB. Significant amplitudes on the transverse components of the RF indicate a shallowly dipping discontinuity (sedimentary-basement) towards the south-west. The fast polarization of SKS phases is near parallel to the border between the continental and the oceanic crust and the Hornsund fault (α = 151.8°). The average time delay dt between “fast” and “slow” directions is 0.68 s, which implies ca. 2% anisotropy in a 100- 200 km thick layer in the mantle.
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Abstract

The near-surface ice thermal structure of the Waldemarbreen, a 2.5-square km glacier located at 78°N 12°E in Spitsbergen, Svalbard , is described here. Traditional glaciological mass balance measurements by stake readings and snow surveying have been conducted annually since 1996. The near-surface ice temperature was investigated with automatic borehole thermistors in the ablation and accumulation areas in 2007-2008. The mean annual surface ice temperatures (September-June) of the ablation area were determined to be -4.7°C at 1 m depth and -2.5°C at 9 m . For the accumulation area, they were -3.0°C at 2 m , and -2.3°C at 10 m depth between September and August. On the Waldemarbreen, at 10 m depth, the mean annual near-surface ice temperature was 4.0°C above the mean annual air temperature in the accumulation area. The Waldemarbreen may thus be classified as a polythermal type with cold ice which is below the pressure melting point and a temperate ice layer in the bottom sections of the glacier and with a temperate surface layer only during summer seasons. At a depth of 10 m , temperatures are of the order of -2°C to -3°C.
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Abstract

Arthropod carapaces have been recovered from the Early Cambrian fossiliferous limestone erratics (dropstones) in the Early Miocene glaciomarine Cape Melville Formation of King George Island (South Shetland Islands), West Antarctica. The arthropod fauna comprises the bradoriide carapaces of Albrunnicola bengtsoni Hinz-Schallreuter, Liangshanella birkenmajeri sp. nov., Melvillella corniculata gen. et sp. nov., Mongolitubulus squamifer Missarzhevsky, Zepaera sp., the phosphatocopid Dabashanella sp., and one problematic taxon. With the exception of M. squamifer, all described species are recorded from Antarctica for the first time. The described Antarctic bradoriide assemblage attests to a close relationship with similar faunas from South Australia and South China, but also includes more widely distributed taxa extending the relationship to the palaeocontinents of Siberia, Baltica and Laurentia.
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Abstract

The aim of this study was to examine the pollution level of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and selected chloroorganic pesticides (HCH isomers, DDT and its metabolites, aldrin, dieldrin, endrin, heptachlor, endosulfan I and II, and methoxychlor) in surface sediments from selected fjords, tidal plains and lakes from the North Svalbard area. The sediments were collected from 34 sampling stations in July 2005. Only endosulfan I and methoxychlor, among selected chloroorganic pesticides, were measured in concentrations near detection limit (LoD) in fourteen sediment samples. The sum of seven PCB congeners varied from < 0.9 to 5.6 ng g-1 d.w. in sediments from fjords and tidal plains and from < 0.1 to 14.6 ng g-1 d.w. in sediments from lakes. The concentrations of analysed PAH compounds in surface sediments from lakes were over ten times higher (Ʃ16PAHs to 429 ng g-1 d.w.) than in sediments from fjords and tidal plains (Ʃ16PAHs to 36 ng g-1 d.w.).
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Abstract

The purpose of this study is to describe the current state of tidewater glaciers in Svalbard as an extension of the inventory of Hagen et al. (1993). The ice masses of Svalbard cover an area of ca 36 600 km2 and more than 60% of the glaciated areas are glaciers which terminate in the sea at calving ice-cliffs. Recent data on the geometry of glacier tongues, their flow velocities and front position changes have been extracted from ASTER images acquired from 2000-2006 using automated methods of satellite image analysis. Analyses have shown that 163 Svalbard glaciers are of tidewater type (having contact with the ocean) and the total length of their calving ice-cliffs is 860 km . When compared with the previous inventory, 14 glaciers retreated from the ocean to the land over a 30-40 year period. Eleven formerly land-based glaciers now terminate in the sea. A new method of assessing the dynamic state of glaciers, based on patterns of frontal crevassing, has been developed. Tidewater glacier termini are divided into four groups on the basis of differences in crevasse patterns and flow velocity: (1) very slow or stagnant glaciers, (2) slow-flowing glaciers, (3) fast-flowing glaciers, (4) surging glaciers (in the active phase) and fast ice streams. This classification has enabled us to estimate total calving flux from Svalbard glaciers with an accuracy appreciably higher than that of previous attempts. Mass loss due to calving from the whole archipelago (excluding Kvitřya) is estimated to be 5.0-8.4 km3 yr-1 (water equivalent - w.e.), with a mean value 6.75 ± 1.7 km3 yr-1 (w.e.). Thus, ablation due to calving contributes as much as 17-25% (with a mean value 21%) to the overall mass loss from Svalbard glaciers. By implication, the contribution of Svalbard iceberg flux to sea-level rise amounts to ca 0.02 mm yr-1. Also calving flux in the Arctic has been considered and the highest annual specific mass balance attributable to iceberg calving has been found for Svalbard.
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Abstract

Artykuł poświęcony jest zjawisku porzucania marynarzy przez ich pracodawców morskich. Kwestia ta od kilku lat jest przedmiotem zainteresowania dwóch organizacji międzynarodowych: Międzynarodowej Organizacji Pracy (ILO) i Międzynarodowej Organizacji Morskiej (IMO). Wydały one w tej materii wspólne wytyczne - ponieważ nie mają one jednak charakteru wiążącego, armatorzy nadal naruszają prawa marynarzy. Spektakularnym przykładem takiego naruszenia jest przedstawiona w artykule sprawa statku “Olga J ”. Przypadek ten jest charakterystyczny dla współczesnej żeglugi, gdyż statek był własnością spółki zarejestrowanej w Belize, czarterowany był przez armatora cypryjskiego, a podnosił banderę Hondurasu. Załoga międzynarodowa: kapitan Grek, marynarze z Ghany, Wysp Zielonego Przylądka i Senegalu. Statek zatrzymany w bułgarskim porcie Burgas, początkowo przez PSC, następnie aresztowany przez władze bułgarskie. Kapitan porzucił załogę, zostawiając ją bez środków do życia, doszło do incydentów z władzami bułgarskimi. Członkowie załogi przez kilka lat starali się o pomoc w różnych organizacjach, w tym w związkach zawodowych. Wreszcie próbowali wykorzystać przepisy o ochronie praw człowieka. Autor przedstawia reperkusje prawne z tym związane.
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Abstract

Gazociąg północny (Nord Stream) od momentu ujawnienia projektu międzynarodowej opinii publicznej stał się najgłośniejszą i najbardziej kontrowersyjną inwestycją w Europie w ostatnich latach. Projekt zakłada budowę rurociągu z Federacji Rosyjskiej do Niemiec na międzynarodowych wodach wyłącznych stref ekonomicznych, w których obrębie prawo morza zapewnia wolności komunikacyjne, włącznie z układaniem tego typu instalacji. Wybór przez konsorcjum Nord Stream jednej z najdłuższych możliwych tras gazociągu, którego budowa jest znacznie droższa niż budowa na lądzie, świadczy o podjęciu decyzji na podstawie przesłanek politycznych, a nie ekonomicznych. Doprowadziło to do niespotykanego od dawna podziału politycznego w regionie na państwa, które potencjalnie odniosą korzyści z inwestycji, i na państwa, w których interesy ta inwestycja godzi. W związku z tym planem pojawiły się problemy związane z zasięgiem jurysdykcji krajowej na morzu, a nawet delimitacją obszarów morskich (spór polsko-duński). Jedną z istotnych z tego punktu widzenia kwestii jest istnienie w Zatoce Fińskiej pasa wód międzynarodowych - „ korytarza morza pełnego ”, którego likwidacja poprzez rozszerzenie morza terytorialnego i ustanowienie granicy fmsko-estońskiej mogłoby uniemożliwić realizację projektu. Bardzo ważną rolę odgrywa tu także aspekt ekologiczny związany z budową i użytkowaniem gazociągu oraz z oceną oddziaływania inwestycji na środowisko, ze szczególnym zwróceniem uwagi na zagrożenie uwolnienia zalegających dno Morza Bałtyckiego bojowych środków trujących z czasów drugiej wojny światowej. W publikacji podkreślono przede wszystkim wybrane prawne i polityczne możliwości oddziaływania przez Polskę na inwestycję, a poza tym zasygnalizowano znaczenie działań wewnątrz Unii Europejskiej oraz słabe strony polskiej administracji rządowej w kontekście planów rosyjsko- niemieckich. Po przedstawieniu założeń projektu w artykule zwrócono uwagę kolejno na zagadnienia ekologiczne związane z budową gazociągu, problem korytarza morza pełnego i gazociągu oraz związek między projektem a delimitacją polskiej i duńskiej wyłącznej strefy ekonomicznej w rejonie Bornholmu.
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