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Soils around the Polish Arctowski Station, Maritime Antarctic were mapped and studied in the lab. They were formed from Tertiary basalt, moraines and solifluction deposits, partly influenced by recent volcanic ash. Regic and Leptic Cryosols as well as Gelic Leptosols on steep slopes without or low vegetation cover were found, whereas very young moraines had Calcari-vitric Cryosols. Moderate slopes below 60 m a.s.l. had Molli-gelic Cambisols with a dense grass cover, whereas the lowlands near the station had Histic and Salic Fluvisols Most soils below 60 m a.s.l. had higher phosphate contents due to the influence of birds, particularly penguins. Cryoclastic weathering together with cryoturbation were the main soil forming processes but chemical weathering took place also. The appearance of pedogenetic iron oxides as well as illites, smectites and allophane in the clay fraction indicate solution-chemical weathering and the new formation of minerals. Some of the soils were influenced by water stagnation, others by ortstein formation. Relatively high contents of organic matter are the result of an absolutely low biomass production but higher in relation to the activity of soil microbes, together with influences of cryoturbation and of the birds.
One of the most significant global climatic events in the Cenozoic was the transition from greenhouse to icehouse conditions in Antarctica. Tectonic evolution of the region and gradual cooling at the end of Eocene led to the first appearance of ice sheets at the Eocene/Oligocene boundary (ca. 34 Ma). Here we report geological record of mountain glaciers that preceded major ice sheet formation in Antarctica. A terrestrial- valley-type tillite up to 65 metres thick was revealed between two basaltic lava sequences in the Eocene- Oligocene Point Thomas Formation at Hervé Cove - Breccia Crag in Admiralty Bay- King George Island- South Shetland Islands. K-Ar dating of the lavas suggests the age of the glaciation at 45-41 Ma (Middle Eocene). It is the oldest Cenozoic record of alpine glaciers in West Antarctica- providing insight into the onset of glaciation of the Antarctic Peninsula and South Shetland Islands.
The paper presents the results of taxonomical investigation of the genus Cladonia Hill ex P. Browne from King George Island. Individuals belonging to this lichen genus were studied using methods of classical herbarium taxonomy supported by chemical analysis. Fourteen species have been recognized in the study area, with C. asahinae J.W. Thomson being reported from King George Island for the first time, and C. cervicornis subsp. mawsonii reported as new for the South Shetland Islands. The occurrence of C. cariosa is confirmed for the Antarctic region. The diagnostic characters, ecology and important remarks referring to particular species are briefly presented. An updated key for identification of the species from King George Island and neighbouring islands of South Shetlands is included.
Ostracods from Admiralty Bay on King George Island (South Shetland Islands) represent 29 podocopid species, belonging to 19 genera, one cladocopid and six myodocopid species. They were recovered from Recent marine and/or glacio-marine sediment samples from water depths of up to 520 m. These ostracods constitute a variable assemblage, which is overall typical for the Antarctic environment. Shallow-water assemblages tend to be more variable in terms of frequencies and species richness than deep-water assemblages. The later are low in numbers and remain relatively high diversities. Overall, no linear relation between ostracod assemblage-composition and environmental features analyzed was recognized.
During the late 2007 austral summer, 20 sediment samples were collected in Admiralty Bay (King George Island, South Shetlands, West Antarctica) from 8 down to 254 m water-depth (mwd). The samples yielded abundant assemblage of monothalamous benthic foraminifera, belonging to at least 40 morphospecies. They constituted the first such collection from Antarctic Peninsula fjords and provided a new insight into this group's diversity and distribution. Among organic-walled taxa, Psammophaga sp., Allogromia cf. crystalli- fera, and three morphotypes of Gloiogullmia were especially abundant. Agglutinated forms were dominated by Hippocrepinella hirudinea, Psammosphaera spp., Lagenammina spp., and various mudballs. Although, the majority of the morphotypes were known from other high-latitude locations, some were reported for the first time. Our quantitative data (>125 |m) showed the greatest differences between monothalamous foraminifera assemblages at shallowest water depths above 50 mwd. The deepest assemblages from between 179 and 254 mwd, were most similar, suggesting uniform near-bottom conditions at ~200 mwd throughout the Admiralty Bay.
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