Between 1979 and 2007, various sampling projects from the Polish Arctowski Research Station in Admiralty Bay, King George Island, Antarctica, collected a diverse assemblage of pycnogonids, inter alia . Examination of this material has revealed 24 species in 11 genera and six families: all of this material is described. Samples were from poorly− sorted fine−sand to coarse−silt substrata, at depths between 27 and 405 m. The diverse assemblage was of species consistent with the known pycnogonid fauna of these depths in the South Shetlands and the Palmer Archipelago region, and includes a number of species re− corded for only the second time since the types. As typical for Antarctic waters, the predominant and most diverse genus was Nymphon (nine species); the prevalent species was Nymphon eltaninae , not Nymphon australe : implications for the apparent wide−distribution of records of the latter species are discussed. These records increase the biogeographical range of Nymphon subtile and Nymphon punctum from Subantarctic waters to the Scotia Sea
This paper presents a complex study on ciliates from the different species of mosses of King George Island, South Shetland Islands, Antarctic. Samples of ciliates were collected from Polytrichastrum alpinum , Sanionia georgico−uncinata , Sanionia uncinata and Brachythecium austrosalebrosum . The highest species richness (19 taxa) occurred in habitats from Brachythecium austrosalebrosum . The lowest number of taxa (5) was observed in Polytrichastrum alpinum . The greatest abundance of ciliates was found in samples from Brachythecium austrosalebrosum (25–30 ind. g −1 ), while the lowest was found in samples from Polytrichastrum (4–6 ind. g −1 ). In each species of mosses, vertical differentiation of these protozoa assemblages was found. The number of species and abundance significantly increased in the lower samples. The upper samples of mosses were dominated by mixotrophic taxa, whereas samples from the lower part the proportions of bacterivore species increases. The RDA performed to specify the direct relationships between the abundance of ciliate taxa and environmental variables showed obvious differences between habitats studied. However, variables that significantly explained the variance in ciliate communities were: dissolved oxygen, pH, and nutrients.
Surface phytoplankton samples were studied quantitatively and qualitatively in February 1996 - November 1998 and January 2003 - November 2005 at the shore and in the center of Admiralty Bay, King George Island. Phytoplankton assemblages showed spring-summer peaks (maxima 4.0-5.2×106 cells l-1) associated with small variations in low atmospheric pressure, and low velocity winds. They were dominated by nano-sized (<20 µm) flagellates and picoplankton (~2 µm). The prevalent nanoflagellates were either Prasinophyceae, Cryptophyceae, or Prymnesiophyceae. Diatoms were next in abundance. Of the seven spring-summer diatom blooms, five had initiated at the shore (maximum 9.8×105 cells l-1; November 1998). They were significantly greater than in the open water, and did not spread into the bay centre. Two observed open water blooms did not reach the shore. Diatoms formed up to 44% of the total cells in the period 1996-98; they only formed <5% in 2003-05. Shore and open water populations differed by diatom dominance structure. Pennates (Fragilariopsis spp., F. cylindrus, Pseudo-nitzschia spp.), and benthic species were prevalent at the shore; centrics (Thalassiosira spp., Chaetoceros socialis) were most common offshore. In 2003-05 diatoms were relatively impoverished in Chaetoceros spp. and the larger (>20 µm) Fragilariopsis spp. Nano-sized Thalassiosira spp. were the winter dominants. Diatom species dominance structure may change at each of the two sites within a month (e.g. shore site: F. cylindrus dominant in October ’98; T. gravida in November ’98). Dinoflagellates showed summer increases associated with diatom blooms. Variations in phytoplankton cell concentrations, the species structures between the shore and open waters, and between seasons appear to be related to physical factors: changes in wind velocity and direction, inflow of waters from the Bransfield Strait, ice melting and changes in atmospheric pressure.
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.
After several years of research, the foraminiferal fauna of Admiralty Bay (King George Island, South Shetland Islands) has become themost studied fiord in West Antarctica with respect to foraminifera. As such, it provides actualistic data for better understanding of paleoenvironmental records from this dynamically changing area. Over a few years, the bay was systematically sampled down to 520 m water depth, for multi−chambered and mono− thalamous benthic foraminifera, including soft−walled allogromiids often overlooked in for− mer studies. Altogether, 138 taxa were identified, and three new taxa described. This paper aims to integrate these results, put them into a broader perspective, and supplement them with information that was not presented to date. Most notably, a record of the vertical distribution of Rose Bengal stained foraminifera below the sediment surface and the proportions of soft and robustly−testate forms at different sites are described.
During thirty three expeditions to the Polish Arctowski Antarctic Station signifi− cant influences of human activity upon the environment have been recorded. Introductions of alien species, shifts of bird and seal breeding areas and decreases in both bird and seal populations, are the most obvious effects of human pressure. Though numbers of visits by tourists have increased during this period, impacts from expeditioners appear to be the main cause of changes. In particular, increasing numbers and mobility of summer groups at the station are the likely most influential factors.
Density, composition and domination structure of the sea ice microalgae in the Admiralty Bay (South Shetland Islands) were investigated in 1983. Algae were recorded both in discoloured and in colourless sea ice from June to October. The highest algae density, amounting to 5 x 105 cells in 1 cm3 was observed till the end of August, the diatoms Nitzschia cylindrus and N. curta being the dominant species. A total of 95 algal taxa. mostly diatoms, were recorded. Air temperature seems to be an important factor influencing the development of algae in sea ice.
Phytoplankton sampling from 13 stations situated in Admiralty Bay was carried out in March. April, May, October and November 1983. Wet settling volume of seston, its dry weight, number of cells under 1 m2 , and qualitative composition of phytoplankton were determined. It was found that amount of phytoplankton was decreasing in April and increasing again in November after the winter season. The share of benthic and periphyton species in the qualitative composition of phytoplankton was quite significant, whereas their quantitative share was rather small. 163 taxa of algae were identified in the net phytoplankton; among these 107 taxa were reported for the first time from the Admiralty Bay. Most abundantly met throughout the entire study period were: Corethron criophilum and Thalassiothrix antarctica.
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.
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.
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.
A new thambematid species, Thambema thunderstruckae sp. n., is described from King George Island, South Shetland Islands, Antarctic. Specimens of the new species were collected during two Polish Antarctic Expeditions in 1985 and 2007. It is the first record of this family from the Southern Hemisphere. The new species most closely resembles Thambema golanachum Harrison, 1987 and T. fiatum Harrison, 1987 but can be distinguished from both species by the shape of male pleopod 1, the number of claws on pereopods 2–7 and the setation of pereopod 1 and 2 carpus, respectively. A key to all known genera and species in the family Thambematidae is also provided.
Several bacteria that are associated with macroalgae can use phycocolloids as a carbon source. Strain INACH002, isolated from decomposing Porphyra (Rhodophyta), in King George Island, Antarctica, was screened and characterized for the ability to produce agarase and alginate-lyase enzymatic activities. Our strain INACH002 was identified as a member of the genus Flavobacterium, closely related to Flavobacterium faecale, using 16S rRNA gene analysis. The INACH002 strain was characterized as psychrotrophic due to its optimal temperature (17°C) and maximum temperature (20°C) of growth. Agarase and alginate-lyase displayed enzymatic activities within a range of 10°C to 50°C, with differences in the optimal temperature to hydrolyze agar (50°C), agarose (50°C) and alginate (30°C) during the first 30 min of activity. Strain Flavobacterium INACH002 is a promising Antarctic biotechnological resource; however, further research is required to illustrate the structural and functional bases of the enzymatic performance observed during the degradation of different substrates at different temperatures.
This review covers aspects of soil science and soil biology of Antarctica with special focus on King George Island, South Shetlands, the martitime Antarctic. New approaches in soil descriptions and soil taxonomy show a great variety of soil types, related to different parent material, mainly volcanic origin, as well as on influences by soil biological processes. The spread of higher rooting plants attract microorga nisms, nematodes and collemboles which in turn build new organic material and change the environment for further successors. Microbial communities are drivers with respect to metabolic and physiological properties indicating a great potential in a changing environment. The literature review also shows a lack of investigations on processes of carbon and nitrogen turnover, despite wide knowledge on its standing stock in different environments. Further , only few reports were found on the processes of humification. Only few data are available which can be regarded as long term monitorings, hence, such projects need to be established in order to follow ecological changes.
Admiralty Bay (King George Island) is an Antarctic Specially Managed Area and one the most thoroughly studied small-scale marine basins in the Southern Ocean. Our study provides new data on the isopod fauna in this glacially affected fjord. Twelve species of isopods were recorded in this basin for the first time. Six of them were found for the first time in the region of the South Shetland Islands. The highest number of species new for Admiralty Bay were found in the families Munnopsidae (4 species) and Munnidae (3 species).
The study was aimed at analyzing patterns of abundance and diversity of macrozoobenthic communities along a depth gradient in the Admiralty Bay, a semi-enclosed basin located in a rapidly changing region of the western Antarctic Peninsula. The study concerns primarily the Polychaeta and Amphipoda, the taxonomic richness and diversity of both groups being analyzed at different taxonomic levels (species, genus and family). Such an analysis, which uses a basic surrogacy measure (low taxonomic resolution) can be very useful in future monitoring programs of the Admiralty Bay. The analysis was based on 35 samples collected in the summer seasons of 1984/85 and 1985/86, with a Tvärminne sampler (within the 7–30 m depth range) and an 0.1 m2 van Veen grab (deeper areas) along a transect with the depth changing from 7 to 502 m. The total macrozoobenthos abundance was found to decrease with depth, from 1581 ± 730 ind./0.1 m2 within the 7–30 m to as few as 384 ± 145 ind./0.1 m2 at 400–500 m. The number of phyla per sample was observed to increase along the depth gradient of 7–30 to 200–300 m but was substantially reduced in the deepest sublittoral (400–500 m). The results showed large differences between amphipods and polychaetes in their respective depth-related biodiversity changes. On the other hand, the diversity metrics used (Pielou’s evenness, Shannon-Wiener index, number of species per sample, number of genera per sample, number of families per sample) at different taxonomic levels within each group produced similar patterns, demonstrating the usefulness of surrogacy in studies of Antarctic fjords.
Diatom assemblages from small pools and creeks on the Ecology Glacier forefield have been investigated. It is the first study in the Admiralty Bay region after the thorough taxonomic revision of the non-marine Antarctic diatom flora. A total of 122 diatom taxa, belonging to 35 genera were identified. More than 55% of all observed species have a restricted Antarctic distribution. Another 15% have a marine origin. Nitzschia gracilis Hantzsch, N. homburgiensis Lange-Bertalot and Planothidium rostrolanceolatum Van de Vijver et al. dominated the flora. Based on a DCA analysis, samples were subdivided in three groups reflecting ecological differences. Several samples (group 1) showed a mixed freshwater/marine diatom composition and are typical for coastal pools. Two other groups were separated based on the amount of limnoterrestrial taxa indicating the temporary character of some of the pools.
The order Passeriformes is the most successful group of birds on Earth, however, its representatives are rare visitors beyond the Polar Front zone. Here we report a photo−documented record of an Austral Negrito ( Lessonia rufa ), first known occurrence of this species in the South Shetland Islands and only the second such an observation in the Antarctic region. This record was made at Lions Rump, King George Island, part of the Antarctic Specially Protected Area No. 151 (ASPA 151). There is no direct evidence of how the individual arrived at Lions Rump, but ship assistance cannot be excluded.
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.
This paper reports the preliminary results from the studies on the scanning electron microscopical studies on chrysophycean cysts collected in ponds and streams of King George Island (South Shetlands). The cysts play an important role as the survival developmental stages. Fifteen morphotypes are described, six of which are new for science. Particular attention has been paid to the anatomy of the pore, collar structure and to the ornamentation of the cyst surface.
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.
In the present paper several species of moss-mites (Acari, Oribatida), including a species new for science (Halozetes impeditus sp. nov.) caught in the vicinity of the Polish "H. Arctowski" Station on King George Island (South Shetlands) are discussed.
The Polish geological research on King George Island, South Shetland Islands (West Antarctica), during the two past decades (1977-1996) included: stratigraphy, radiometric dating, petrology and geochemistry, sedimentology and palaeoenvironmental studies, volcanology, tectonics, structural geology, Quaternary geology, paleobotany and palaeozoology. The major scientific achievements were: (1) the establishment of formal lithostratigraphic standards for radiometrically-dated Upper Cretaceous through Tertiary magmatic rock sequences and intercalated sediments; (2) the discovery of four Tertiary glaciations and three interglacials, spanning some 30 Ma from Early/Middle Eocene through Early Miocene; (3) the discovery and systematic elaboration of rich terrestrial and marine biota of Late Cretaceous through Early Miocene ages; (4) the reconstruction of changing Late Cretaceous and Tertiary terrestrial and marine palaeoenvironments in a mobile volcanic-arc setting; (5) the determination of age and structural evolution of the island's two Quaternary volcanoes; (6) the reconstruction of the Late Cretaceous through Recent evolution stages of the South Shetland magmatic arc and its backarc Bransfield Basin and Rift, based on tectonic and structural studies.
An additional account on the Oligocene cyclostome Bryozoa has been made from the glaciomarine sediments of the Low Head Member (= Pecten conglomerate of Barton 1965) of the Polonez Cove Formation on King George Island (South Shetland Island, West Antarctica). The following genera have been recognized for the first time in Paleogene of Antarctica: Crista, Bicrisia, Exidmonea, Filisparsa and Mecynoecia. Paleoecological interpretation of the bryozoan assemblage implies that the fauna lived in shallow water at a depth of around 50 m.