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Number of results: 18
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Abstract

New coral taxa Tetraporinus siedlecka sp. n. and Roemeripora aspinosa major ssp. n. are erected from the Lower Permian (Sakmarian and Artinskian) Treskelodden Formation of Hornsund area, Spitsbergen and Syringopora sp. similar to S. subreticulata Nowiński, 1991 are described. Studies on stable isotope ratios of carbon and oxygen in the skeletons of tabulate and rugose corals from Hyrnefjellet and Treskelen areas show that these organism did not frac­tion the isotopes to much. The differences in isotope fractionation, both for carbon and oxygen, reached 2 ‰ comparable to the concurring brachiopods, accepted as reference level.
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Abstract

The Marhegda Bed is a carbonate-dominated Uthostratigraphic unit occurring locally at base of the Middle-Late Jurassic organic-rich sequence of the Agardhfjellet Formation in Spitsbergen, Svalbard. It has been interpreted to represent oolitic limestone facies deposited during an initial stage of Late Jurassic transgression. Petrographic, major element geochemical, and stable carbon and oxygen isotopic data presented in this paper indicate that this litho-stratigraphic unit is not a depositional limestone, but a diagenetic cementstone band originated in organic-rich sediment containing glauconite pellets and phosphatic ooids and grains. Two ep­isodes of carbonate diagenesis, including early precipitation of siderite and burial precipitation of ankerite, have contributed to the development of this cementstone. Extensive siderite precipi­tation occurred at sedimentary temperatures in nearsurface suboxic environment in which microbial reduction of ferric iron was the dominant diagenetic process. Precipitation of ankerite occurred at temperatures of about 80-100°C in burial diagenetic environment overwhelmed by thermal decarboxylation processes. Formation of ankerite was associated with advanced alteration of glauconite, dissolution of apatite and precipitation of kaolinite.
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Abstract

During four Polish Geodynamical Expeditions to West Antarctica between 1979 and 1991, seismic measurements were made along 21 deep refraction profiles in the Bransfield Strait and along the coastal area of Antarctic Peninsula using explosion sources. Recordings were made by 16 land stations and 8 ocean bottom seismometers. Good quality recordings were obtained up to about 250 km distance. This allowed a detailed study of the seismic wave field and crustal structure. Three-dimensional tomographic inversion was carried out using first arriv­als from the complete data set including off-line recordings. As a result, we obtained a 3-D model of the P-wave velocity distribution in the study area. In the area adjacent to the Antarctic Peninsula coast, sedimentary cover of 0.2 to 3 km thickness was found, whereas in the shelf area and in the Bransfield Strait sedimentary basins with thickness from 5 to 8 km were observed. In the Bransfield Strait a high velocity body with Vp > 7.5 km/s was found at 12 km depth. The use of the off-line data allowed for determination of the horizontal extent of the body. The thickness of the crust varies from more than 35-40 km in the coastal area south of the Hero Fracture Zone to 30-35 km in the area of Bransfield Strait and South Shetland Islands and about 12 km in the Pacific Ocean NW of South Shetland Islands.
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Abstract

Body size is an important measure in biology and especially in paleobiology. With respect to fossil penguins from the Eocene La Meseta Formation of Seymour Island (West Antarctica) the overall size has to be judged from the dimensions of single bones. The analysis based on selected measurements of hind limb bones from the Polish collection of Eocene Ant­arctic penguins yielded results supporting predictions published formerly. Estimated body masses and lengths indicate that mean interspecific body size of extinct Antarctic Spheniscidae exceeded that of Recent species.
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Abstract

In total, 18 species and larval forms of endoparasitic worms were found in 19 newly examined notothenioid fishes of three species, Trematomus hansom, Notothenia coriiceps and Chionodraco hamatus, caught off Adelie Land. One digenean species, Neolepidapedon trema-tomi, was recorded in this area for the first time. A total list of endoparasitic worms prepared by Zdzitowiecki etal. (1998) increased from 20 to 21 species and larval forms and concerns 11 deter­mined and one determined species of Digenea (the most diverse group), three larval forms of Cestoda, three species (one identified only to genus) of Acanthocephala, two species (one in the larval stage) and one larval form of Nematoda. All these species and forms, with the exception of the indetcrmined digenean, occur also in the deep Antarctica, in the Ross Sea and/or in the Weddell Sea. The prevalence and relative density of infection with each parasite in three host species is given based on summarized previous and new data.
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Abstract

Scavenging fauna was sampled by means of baited traps in three different habitats of Kongsfjorden (Svalbard, Arctic). Lysianassoid amphipods, represented by nine species, made up 98.9% of the materials collected between 5 and 30 m. The dominant species were Anonyx sarsi and Onisimus caricus, which constituted 91.6% of collected individuals. The abundance of animals attracted to traps was variable and a gradual decrease in abundance with increasing depth was observed. Spatial segregation of species resulted from a number of factors ranging from depth, hydrological conditions, sedimentation regime and bottom type to food accessibility. Gut contents analysis indicated that in summer Onisimus caricus relied on zooplankton sinking due to the osmotic shock in the glacial bay; Onisimus edwardsi had a diverse diet; and Orchomenella minuta fed mostly on small crustaceans. During laboratory experiments all species were observed feeding on dead or injured zooplankton, while preying on live planktonie organisms was never noted.
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Abstract

The species diversity of the Bryozoa in Kongsfjorden was determined based on quantitative, depth-stratified (0-30 m) samples collected by SCUBA divers (1996, 1998). One hundred and one species and 16 varieties of the three orders Cyclostomata, Ctenostomata and Cheilostomata - are reported from Kongsfjorden. Ten species are presumably new. The bryozoan fauna of Svalbard is mainly represented by Arctic and boreal-Arctic species and varieties. The few amphiboreal and subtropical-boreal species found most likely reach their northern limit of distribution near Spitsbergen. The distribution of the Bryozoa within Kongsfjorden was determined by depth and location sampled. The number of taxa increased, generally, with depth and distance from tidal glaciers located in the inner fjord. Relative decreases in species number occurred at 15-20 m depth in the middle to outer fjord. This is most likely explained by a change of water mass properties, i.e. a transition from the surface water layer to deeper marine water.
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Abstract

In total, 8511 amphipods of 12 species caught in Admiralty Bay were examined for the presence of acanthocephalans using them as intermediate hosts. Only 27 specimens of eight species were infected (total prevalence 0.32%). Acanthellae and cystacanths of four species using fishes as either definitive or paratenic hosts were found. Normally, single parasites occurred; in one case two acanthocephalans were present in one specimen of Bovallia gigantea. This host species was the most strongly infected, with the prevalence 3.41%. Six other amphipod species were infected with the prevalence 0.08-0.66%. One of two Jassa ingens examined was also infected. Over 50% of acanthocephalans belonged to one echinorhynchid species maturing in fishes, Aspersentis megarhynchus, which occurred in five host species of four amphipod families, B. gigantea, Gondogeneia antarctica, J. ingens, Hippomedon kergueleni and Orchomenella rotundi-frons. Two polymorphid species maturing in seals, Corynosoma hamanni and C. pseudohamanni, were found in a single host species each, Prostebbingia brevicornis and Cheirimedon femoratus, respectively. Three parasite species mentioned occurred exclusively in sublittoral host species, at the depth 0-30 m. The third polymorphid species, C. bullosum, was the only species occurring in the amphipod, Waldeckia obesa, living in the deeper water (infected specimen was caught at the depth 60 m), but was found also in B. gigantea. Differences between infections of Amphipoda and fishes with echinorhynchids and polymorphids are discussed.
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Abstract

In November 1994 a first inventory of Tanaidacea from the Beagle Channel and at some stations of the Atlantic continental shelfwas obtained using epibenthic sledge samples. In total, 2175 specimens from 27 species of eight families of Tanaidomorpha and two families of Apseudomorpha were collected. Two species, Allotanais hirstutus (Beddard, 1886) and Apseudes heroae Sieg, 1986, strongly dominated this area. Generally low diversity and abundances were recorded for the western area of the Beagle Channel, while substantially higher values were reported at the eastern entrance on the Atlantic side of the Beagle Channel. Abundances slightly varied with depths, but not significantly.
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Abstract

A serological study to detect antibodies against microbes in avian mycoplasmosis (Mycoplasma gallisepticum and M. synoviae), and salmonellosis (Salmonella gallinarum and S. pullorum) was carried out. A hundred and twelve Antarctic birds (42 Adelie penguins, Pygoscelis adeliae, 30 southern giant petrels, Macronectes giganteus and 40 skuas, Catharacta antarctica and C. maccormicki) from King George Island, the South Shetland Islands, and Laurie Island, the South Orkney Islands in Antarctica were studied. The serological test used in this study was a rapid agglutination test. According to the results and considering the number of samples analysed, it is reasonable to believe that Adelie penguins, southern giant petrels, and skuas populations of the areas mentioned above are free from mycoplasmosis and salmonellosis.
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Abstract

Certain chemical parameters such pH, specific electric conductivity (SpC) and concentrations of chloride ions (Cl-) have been analysed in samples of precipitation collected close to the Polish Polar Station at Hornsund (PPS), SW Spitsbergen. On the basis of seasonal data from years 1993-1994 and 1998-1999, some differences are apparent from the two sets. There is also a marked difference in the seasonal results, especially with respects to pH values; summer precipitation (pH of which can be as low as 3.78) is much more acidic than winter. This was particularly notable in respect of the summer of 1993, and was presumably the result of a relatively unusual atmospheric circulation and a high influx of airborne contaminants from Europe. The wide variation in specific electrical conductivity measurements is considered to be related to variations in wind direction and speed. That precipitation the highest total dissolved salts, of 11.7 mm w.e. (water equivalent), (November 1993), provided 10.7 g of salt per square metre of tundra near the Polish Polar Station. The proximity of the sea, consequently the development of marine aerosols, largely determines the chemical nature of the precipitation. Thus, variations in the chloride ion concentrations during the study periods more or less reflect the variations in the marine aerosol influences on the nature of the polluted precipitation. An analysis of the atmospheric circulation reveals that the most acid precipitation occurs most frequently in the C-8 type of circulation (cyclonic S + SW) and also, less so, for type C-3 (anticyclonic S + SW).
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Abstract

During the cruise of the research ship r/v Oceania owned by the Institute of Oceanology of the Polish Academy of Sciences in Sopot a research on mineral suspension concentration and dispersion distributions was conducted. The research area included the western part of the Baltic Sea, the Danish Straits, the Norwegian Sea, the waters around Spitsbergen and the North Atlantic Ocean. Samples of water were collected from the surface layer. They were subjected to microscopic analysis. Measurements were done with a projection microscope (magnification lOOOx) and using the Burker's table. After counting the particles dispersion distribution was determined. The largest concentration of mineral suspension was noted offshore in the Norwegian Sea and around Spitsbergen and the smallest in the central Atlantic Ocean.
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Abstract

Non-crustacean plankton was studied during summer cruises to the northern Nor­wegian Sea from 1996 to 1998. The dominant species in the investigated area were Aglantha digitale (Hydrozoa) and Sagitta elegans (Chaetognatha). The average density, mean biomass and interannual changes of zooplankton are presented against the background of sea tempera­tures. The results of this work indicate the very strong inter-annual variability of non-crustacean zooplankton abundance. Correlations with minor changes in sea temperature were noted only for hydromedusae.
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Abstract

Sixty seven zooplankton taxa were recorded in a total of 5 WP-2 net vertical hauls carried out in a year round cycle in Admiralty Bay. Copepoda were the most common and abundant group and Oithona similis was the dominant species throughout the area. Polychaeta, Ostracoda and Chaetognatha were also rather common and abundant. Euphausiacea, Amphi-poda and Salpae occured mainly in the central part and the outlet area of the bay. No differences in zooplankton assemblages diversity in the four investigated areas of Admiralty Bay were en­countered. However, distinct differences in species richness between the zooplankton of Ezcurra Inlet and the main basin of the bay were observed. The composition of zooplankton was rather stable throughout the year, but seasonal occurrences of larvae of Polychaeta, Crustacea, Echino-dermata and Ascidiacea were noted. A Ust of the 174 zooplankton taxa ever found in Admiralty Bay is presented by combining the present results with the existing scientific data.
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Abstract

This paper presents preliminary data on the population structure of two Antarctic crustaceans Eudorella splendida and Nototanais antarcticus, commonly occurring in Admiralty Bay (South Shetland Islands). From analysis of the material studied it can be concluded that N. antarcticus is a progynous hermaphrodite with a life cycle lasting at least two years. The life cycle of E. splendida lasts probably 3-4 years. It is a semelparous species, but some females after brooding moult and revert into the intermediate stage.
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Abstract

Objects that have come within the inventory are the effect of whaling activity car­ried out in the region of South Shetland Islands in the first half of the twentieth century. They in­clude mainly bones of hunted animals, rarely wooden or metal objects, part of which may be re­lated to the whaling industry. In this paper the areas of particular accumulation of these objects have been determined, and the attempts to explain the reasons for such accumulations have been made. In addition, certain suggestions for further investigations into whaling activity in the South Shetland Islands region have been put forward. During the work 158 large fragments of whale skulls, among others, have been inventoried. The total number of individuals whose pre­served relics have been explored within the surveyed sections of the Admiralty Bay shores has been estimated to be 210-230.
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