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Number of results: 19
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Abstract

Upper Cretaceous calcareous nannoplankton recycled into the Pliocene Pecten Conglomerate of Cockburn Island (Antarctic Peninsula) provide a paleontological record of Upper Cretaceous sedimentary sequences in the James Ross Basin. The calcareous nannofossil assemblage comprises nearly 40 taxa and is dominated by Campanian-Maestrichtian species. The investigated assemblage shares some features with the southern high-latitude contemporaneous calcareous nannofossil assemblages from outcrops on adjacent Seymour (Marambio) Island and many with deep-sea drilling sites in the circum-Antarctic region.
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Abstract

On the basis of about 12500 depth measurements of which 6700 were taken from r/v Profesor Siedlecki, 1300 from r/v Polarstern and the remainder from British navigation charts, a bathymetric chart of the Bransfield Strait in the scale 1:500 000 has been prepared. Within the assumed boundaries the total area of the Bransfield Strait covers 65308.6 square kilometres, of which the Western Basin covers 23.5%, Central Basin — 47.3%, and Eastern Basin 29.2%. Capacity of the whole Bransfield Strait amounts to 38451 km3 . The average depth of the Bransfield Strait is 592 m.
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Abstract

Fossil bird remains assignable to ratites (palaeognathous birds) are described from the Paleogene strata of the La Meseta Formation of Seymour Island, Antarctic Peninsula. This record sheds new light on Gondwana's avian history.
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Abstract

Roemeripora tollinoides sp. n. (Anthozoa, Tabulata) is described from Upper Carboniferous strata of SW Nordenskiöld Land (Ingeborgfiellet), Bellsund area in West Spistbergen (Svalbard). The new species is characteristic for a phacelo-cerioid structure of entire corallum.
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Abstract

Septal neck-siphuncular complex has been redescribed In Triassic (Carnian) Stolleyites tenuis (Stolley). Ammonites whose septal necks change orientation from retrochoanitic through intermediate to prochoanitic may be divided into two categories: dorsoprogressive and ventroprogressive. In the former category, the initial changes in the direction of septal necks orientation occur dorsally; in the latter, the ventral side exhibits more progressive changes. Among forms with siphuncular complex adjacent to the ventral wall, i.e., without a septum between the neck and ventral wall in the medial plane, the changes towards prochoanitic septal neck may begin in the ventrolateral part. The circumsiphonal invagination in those forms did not include the ventral part and their proper interpretation cannot rely on the medial plane only. Primary lamination and primary fibrous structure of the siphuncular tube had been described, as well as the microstructure of the distal tip of cuff and auxiliary deposit.
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Abstract

Research in Hornsund (SW Spitsbergen) aimed to determine time distribution of heat flux in various soils of Arctic periglacial zone in spring and summer. Typical soils were analysed: tundra gleyey cryogenic soil (Pergelic Cryaquent), tundra peaty soil (Pergelic Histosot) and arctic desert soil (Pergelic Cryorthent). Research sites were located in low plains not covered with ice, near a sea, at 7—13 m a.s.l. Heat flux in soils was measured and recorded automatically every 60 s throughout a whole observation period and concurrently at three sites. In spring and summer intensive heat accumulation was observed in all examined soils. Independently on the weather, a cryogenic gleyey soil received greatest heat throughout a day. Environmental conditions have distinct influence on heat resources in soils.
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Abstract

On the basis of elemental composition, optical properties in the visible region, infrared spectra and thermal analysis (TG, DTG, DTA), humic acids of tundra soils in Spitsbergen are found to be more similar to fulvic acids than to humic acids of soils from other soil-climatic zones. The authors claim that it results from climatic conditions (low temperature, considerable humidity, alternation of freezing and thawing) and specific biochemical composition of tundra plants (predominance of plants devoid of lignin) which constitute substratum of the studied humic acids.
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Abstract

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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Abstract

The present paper contains a list of 104 taxa of lichens and lichenicolous fungi, found in the Cape Lions Rump, Site of Special Scientific Interest No. 34 (King George Island, Antarctica), with their distribution and ecological analysis. A provisional vegetation map of the area is also provided. During the field survey the data were collected using the cartogram method in a grid of squares 250 x 250 m. The current abundance and spatial distribution of lichen species provides baseline data for long-term monitoring biological changes.
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Abstract

The length of crystalline cones (cc) is proportional to krill body length and this proportion can be described by the equation L cc = L krill x 1.679 + 52.032 ( cc — μm; L krill - mm). By measuring cc one can determine the size of krill with the precision of 2—3 mm. The structure of crystalline cones is not crystal, and the elemental composition includes much of S and Ca. Crystalline cones are often found in the stomach and feces of animals feeding on krill.
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Abstract

Moulting southern elephant seals, Mirounga leonina (L.), were counted in 17 discrete wallows at Walker Bay on Livingston Island in the South Shetland Islands between 2 January and 16 February 1994. Daily weather conditions were also recorded. It was also found that, although there were no overall correlations between wind scale, air temperature, sunshine, precipitation, sea roughness and cloud cover with seal numbers, there were conditions on specific days that affected the movements of seals between wallows. Most notably, it was found that numbers of seals decreased when they were exposed to winds, and that they often sought out more sheltered sites nearby.
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Abstract

Changes in body mass and body reserves of Little Auks (Alle alle) were studied throughout the breeding season. Body mass loss after chick hatching was analyzed with respect to two hypotheses: (1) mass loss reflects the stress of reproduction, (2) mass loss is adaptive by reducing power consumption during flight. Body mass of both males and females increased during incubation, dropped abruptly after hatching, and remained stable until the end of the chick-rearing period. These changes were largely due to change in mass of fat reserves. Body mass, fat, and protein reserves, when corrected for body size, did not differ between sexes at the end of incubation. Female size-corrected body mass at that time was correlated with peak body mass of chicks. The estimated energy savings for flight due to the decline in adult body mass after chick hatching were small compared with the total energy expenditure of adults feedings chicks, which did not support hypothesis (2). The contribution to chick feeding was not equal; the ratio of females to males caught with food for chicks was 1.8. Size-corrected body mass during chick-rearing was lower in females, proportional to their higher chick feeding effort compared with males. Females, in contrast to males, lost protein reserves during chick-rearing. Digestive tract mass of adults increased by half throughout the breeding period. These findings supported elements of hypothesis (1). Despite high energy expenditure rates, both sexes had about 10 g of fat reserves at the end of chick feeding. Body mass of both sexes was constant during the greater part of the chick-feeding period. It was suggested therefore that mass loss is regulated with respect to lower fat reserves required during chick-rearing.
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Abstract

Przedstawiono wykaz nowych nazw geograficznych wprowadzonych na obszarze Wyspy Seymour (Marambio), Półwysep Antarktyczny (fig. 1, pl. 1—2) w czasie prac terenowych argentyńsko-polskiej grupy geologicznej w sezonie 1993-1994.
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