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Number of results: 19
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Abstract

The paper presents the trends of air temperature of the Antarctic. In its elaboration 21 stations were taken into consideration carrying out temperature measurements in the years 1958–2000, and 34 stations in the years 1981–2000. After checking the homogeneity of the series by the Alexandersson’s (1986) test we found that at 16 stations the homogeneity has been broken. On the basis of the corrected measurement series we have determined the trends in air temperature. In the period 1958–2000 statistically significant (on 0.95 significance level) temperature increases occurred on the western coast of the Antarctic Peninsula (for example Faraday 0.67°C/10 years) and at the Belgrano and McMurdo stations. The greatest temperature rise was noted on the Antarctic Peninsula during the autumn-winter period. On the South Pole a negative trend in air temperature (–0.21°C) occurred, especially in the summer season. During recent years (1981-2000) significant changes took place in the air temperature tendencies in the Antarctic. In many regions of the Antarctic cooling began and on the cost of East Antarctica the temperature decreased by –0.82°C/10 years (Casey). In the interior of the continent also lower and lower temperatures occurred (Amundsen-Scott –0.42°C/10 years, Dome C –0.71°C/10 years). The coast of the Weddell Sea is getting colder (Halley –1.13°C/10 years, Larsen Ice –0.89°C/10 years). An increase in temperature was observed in the interior of West Antarctica (Byrd 0.37°C/10 years). The warming rate of the climate became weaker on the Antarctic Peninsula (Faraday 0.56°C/10 years). The largest temperature changes occurred in the autumn-winter season when in the Antarctic Peninsula region the temperature increased, while in the interior and at the coast of East Antarctica temperatures fell considerably.
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Abstract

Energy delivered to the nests of Wilson's storm petrel, Oceanites oceanicus (Kuhl, 1820), was evaluated by measurement of the oxygen consumption of brooding adult birds and nestlings of different ages. During the brooding period adult birds have to deliver more than 180 kJ per visit to the nest vs. less than 170 kJ during the rest of the nesting period. It seems likely that the parental ability to deliver large quantities of food per visit affects the duration of the brooding period and therefore also affects growth rates of Wilson's storm petrel chicks and the duration of their nesting period.
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Abstract

The diet of the unsexed breeding Adélie penguin (Pygoscelis adeliae Hombron et Jacquinot, 1841) was investigated during three consecutive chick rearing periods, from 1996–97 to 1998–99, on Laurie Island, South Orkney Islands (60°46’S, 44°42’W), Antarctica. This analysis showed that during the whole sampling period, Antarctic krill (Euphausia superba Dana, 1852) represented the predominant prey in terms of frequency of occurrence, mass, and number. The hyperiid amphipod Themisto gaudichaudii (Guerin-Méneville, 1825) was present in small amounts. Electrona antarctica (Gunter, 1878), Trematomus newnesi (Boulenger, 1902) and larval stages of Nototheniidae constituted the bulk of the fish portion, particularly during the 1997/98 and 1998/99 breeding periods. This study is the first examination of the Adélie penguin diet at Laurie Island. It is important to recognize, however, the importance of knowing the sex of the penguins being sampled and that prey composition may vary during the breeding season and from one year to the next.
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Abstract

A population survey of southern elephant seals (Mirounga leonina Linnaeus, 1758) was conducted at Nelson Island, South Shetland Islands, Antarctica, during the 2001 breeding season. Two breeding sites were identified, one of which had not been previously reported. The largest breeding site was located at Duthoit Point, with a total of 128 females, 111 pups and 7 weanlings distributed in 6 harems along 3 km of coast. The new breeding group was observed at Harmony Point, where 3 females with their pups were found. This is the first report on southern elephant seal numbers during the breeding period for the Nelson Island coast.
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Abstract

The zooplankton community structure was studied in the Svalbard area at three shelf stations: Billefjorden, Kongsfjorden and Hinlopen (Spitsbergen shelf area), and at two open water stations: Ice West and Ice East (north of Spitsbergen, in the Arctic Ocean). Two different plankton nets – WP-2 and WP-3 – were used to collect a size range of zooplankton. The Bray-Curtis similarity analysis showed differences between sampling stations based on total zooplankton abundance, species composition, and comparison of Calanus spp. development. Total abundance was the highest in Kongsfjorden and Hinlopen. The small omnivorous copepod Oithona similis Claus, 1863 was the dominating species at all localities and the Atlantic copepod Calanus finmarchicus (Gunnerus, 1765) was found at all stations. Calanus spp. development was delayed at the ice stations when compared to the shelf stations. Results are discussed in relation to differences in environmental factors among stations.
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Abstract

Mud samples from two lakes in West Greenland were kept frozen at –18°C for 18 years. When they were thawed, 4 Cladocera species hatched from diapausing eggs: Daphnia pulex (De Geer, 1778), Macrothrix hirsuticornis (Norman et Brady, 1867) and Chydorus arcticus (Rřen, 1987), which are by far the most abundant Cladocera species in the high Arctic north of 74°N. Another species was Alona quadrangularis (O. F. Müller, 1785), which occurs up to 72°N. All these species gave rise to parthenogenetic offspring and produced ephippia within a time frame comparable to an Arctic summer season. Up to 9 other Cladocera species were likely to be present in the original populations, but did not hatch anymore after 12 years.
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Abstract

Molluscan fossils accompanied by familiar SSF have been recovered from Early Cambrian limestone erratics in the Early Miocene glaciomarine Cape Melville Formation of King George Island, West Antarctica. The molluscan fauna comprises the hyoliths Conotheca, Microcornus, Parkula, Hyptiotheca, “Hyolithes”, the helcionelloids ?Pararacornus, Yochelcionella, Anabarella, the low dextrally coiled Pelagiella and the high helically coiled Beshtashella, as well as the problematic mollusc Cupitheca. Most of described species are recorded here for the first time from Antarctica. The lithological and fossil contents of the erratics are almost the same as from autochthonous successions the Shackleton Limestone in the Argentina Range and Transantarctic Mountains. Early Cambrian outcrops around the Weddell Sea are a probable source of the erratic boulders. The Antarctic fauna is very similar to that from uppermost Botomian and Toyonian carbonate deposits in the Cambrian Basins of South Australia. These faunal and facies similarities between Antarctica and Australia confirm their neighbouring position and common biotic and basin evolution on the Cambrian Gondwana margin.
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Abstract

Ball-shaped concretions ("cannon balls") commonly occur in a marine, organic carbon-rich sedimentary sequence (Innkjegla Member) of the Carolinefjellet Formation (AptianAlbian) in Spitsbergen. The sedimentologic, petrographic and geochemical investigation of these concretions in the Kapp Morton section at Van Mijenfjorden gives insight into their origin and diagenetic evolution. The concretion bodies commenced to form in subsurface environment in the upper part of the sulphate reduction (SR) diagenetic zone. They resulted from pervasive cementation of uncompacted sediment enriched in framboidal pyrite by non-ferroan (up to 2 mol% FeCO3) calcite microspar at local sites of enhanced decomposition of organic matter. Bacterial oxidation of organic matter provided most of carbon dioxide necessary for concretionary calcite precipitation (δ13CCaCO3 ≈ -21%VPDB). Perfect ball-like shapes of the concretions originated at this stage, reflecting isotropic permeability of uncompacted sediment. The concretion bodies cracked under continuous burial as a result of amplification of stress around concretions in a more plastic sediment. The crack systems were filled by non-ferroan (up to 5 mol% FeCO3) calcite spar and blocky pyrite in deeper parts of the SR-zone. This cementation was associated with impregnation of parts of the concretion bodies with microgranular pyrite. Bacterial oxidation of organic matter was still the major source of carbon dioxide for crack-filling calcite precipitation (δ13CCaCO3 ≈ -19% VPDB). At this stage, the cannon-ball concretions attained their final shape and texture. Subsequent stages of concretion evolution involved burial cementation of rudimentary pore space with carbonate minerals (dolomite/ankerite, siderite, calcite) under increased temperature (δ18OCa,Mg,FeCO3 ≈-14% VPDB). Carbon dioxide for mineral precipitation was derived from thermal degradation of organic matter and from dissolution of skeletal carbonates (δ13CCa,Mg,FeCO3≈ - 8‰ VPDB). Kaolinite cement precipitated as the last diagenetic mineral, most probably during post−Early Cretaceous uplift of the sequence.
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Abstract

Measurements of CO2 concentrations in soil air were taken in the summer seasons of 1998 and 2001 in SW Spitsbergen. The measurements were carried out in three small non-glaciated catchments in the Hornsund region close to the Polish Polar Station. The preliminary measurements were made using a Dräger's pump and ampules which contained an alkaline absorbent (1998). Later (2001), a new more accurate apparatus which uses a gravimetric method was tested. A variety of different geographical situations was chosen for the CO2 measurements. These included areas which differed in respect of the local hydrology, terrain relief, exposure to solar radiation, distance from the sea and quantity of seabird excrements in the soil. The measured concentrations of soil CO2 varied between 0.05 and 0.3% (with one exceptionally high value close to 0.5%). Owing to the local conditions, the differences between CO2 concentrations seem closely to relate to the specific properties of each catchment. Much of the biogenic CO2 present in water that circulates in tundra catchments which have a limestone foundation becomes involved in the dissolution of that limestone. In July 2001, about 40% of the CO2 was used in the dissolution of the carbonate rocks (30.3 kg/km2 month), the “free” CO2 being transported to the sea at Isbjřrnhamna Bay (40.4 kg/km2 month). In contrast, the water flowing through acidic rocks are rich in “free” CO2. The concentrations of dissolved and transported HCO3– ions from the polar catchments are closely correlated with variations in the daily production of biogenic CO2.
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Abstract

The paper comprises the review of all known species of cestodes parasitizing the Antarctic and Subantarctic fishes along with synonyms and keys based on morphological features. Also, the review of larval forms of cestodes occurring in bony fishes and provisional identification of them with adult forms is given. In total, 11 valid species (and 3 unnamed forms) of the order Tetraphyllidea and Diphyllidea occur in skates, whereas 3 species of the order Pseudophyllidea were reported from bony fishes. Six morphological forms of larvae, 5 belonging to the Tetraphyllidea and one to the family Tetrabothriidae as well as undetermined plerocercoids of Diphyllobothriidae were recognized.
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Abstract

Recent foraminifera represented by 24 species belonging to 20 genera are recognized in marine and/or glacio-marine sediment samples collected at water depths of up to 75 m in Goulden Cove (Admiralty Bay) on King George Island, West Antarctica. The foraminifer assemblages are dominated by benthic taxa, such as Globocassidulina biora and Miliammina arenacea, the two most abundant species in the studied biocenosis.
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Abstract

An isolated, deciduous incisor of an archaic whale found in the upper part of the La Meseta Formation (Telm7) is tentatively assigned to the Archaeoceti. The strata from which the tooth was recovered are of Late Eocene (Priabonian) age, and previous reports indicate that they contain the remains of Dorudontinae (Archaeoceti) and Llanocetidae (Mysticeti). The tooth is similar in shape, size and ornamentation to the milk teeth of Zygorhiza. The enamel is mostly prismatic, with prism sheats generally open, except for the outermost layer, which is aprismatic. The Schmelzmuster consists of radial and decussating enamel types. The decussating zone has distinct Hunter-Schreger bands (HSB), usually consisting of 10–12 prisms. It is bordered by an external zone built of radial enamel extending for 22% of the enamel thickness and an internal, starting zone, with less developed HSB, occupying 9% of the enamel thickness. The interprismatic matrix is parallel to the prism direction. An archaeocete origin of the tooth is suggested by its enamel features, typical for the group. However, additional study of the Llanocetidae enamel structure is needed for final identification.
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Abstract

Until now Eocene chimeroid holocephalians of Antarctica have been known from only a few specimens attributed to two species from the Eocene of Seymour Island. New material collected by Polish and English field parties includes numerous tooth plates and fin spine fragments from the Eocene La Meseta Formation. We describe a new species, Callorhinchus stahli, based on two mandibular and a single fragmentary palatine tooth plate. In addition, the stratigraphic distribution and diversity of Eocene Antarctic chimeroids is discussed. The chimeroid Ischyodus shows the greatest stratigraphic distribution with its greatest abundance in the middle parts of the La Meseta Formation while Chimaera and Callorhinchus are restricted to the lower ones. Changes in the environment and habitat availability most probably triggered the distributional pattern and the disappearance of chimeroids.
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Abstract

A topographic map 1:12,500 scale of the SSSI No. 8 and the Arctowski Station region was prepared during the XXV Polish Polar Expedition (2000/2001) organized by the Department of Antarctic Biology, Polish Academy of Sciences. The map documents geomorphological changes which took place during the last 20 years. Several new place names have been introduced for the SSSI No. 8 area.
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Abstract

The Lidfjellet thrust is the most prominent tectonic structure in the Lidfjellet-Řyrlandsodden fold zone, which stretches NNW-SSE along the western coast of Sřrkapp Land in Spitsbergen. This paper provides a reinterpretation of the Lidfjellet structure, with particular reference to lithostratigraphy of the autochthonous and overthrust sequences involved, and to the position of the thrust surface. Geological and palynologicalal data indicate that the sequence attributed previously to the Lower Cretaceous Helvetiafjellet Formation of the autochthonous cover represents in fact the Carboniferous (Viséan) Sergeijevfjellet Formation forming the lower part of the overthrust unit. The youngest deposits involved in tectonic structures of the Lidfjellet-Řyrlandsodden fold zone are of Upper Jurassic age.
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Abstract

Soft bottom fauna have been sampled along the Spitsbergen fjord depression entering shelf, slope and Greenland Sea Ocean Basin at 200, 300, 500, 1500, 2000 and 3000 m depths. From 19 samples covering 1.9 m2, 4295 individuals of 194 macrofauna species have been sorted. Density decreased markedly from over 6000 ind/m2 in shelf stations to some 600 ind/m2 below 1500 m depth. Only two taxa (Chaetozone group and Lumbrineris sp. A) occurred in more than 75% of samples, 55 taxa (28% of the total) were represented by single specimens only. The highest number of species per sample (65 taxa in 0.1 m2) was noted at 525 depth. There were 14 eurybathic species and the same number of taxa were found exclusively below 2000 m depth, while 117 species were found only shallower than 300 m depth.
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