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Number of results: 94
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Abstract

The active distribution network (ADN) represents the future development of distribution networks, whether the islanding phenomenon occurs or not determines the control strategy adopted by the ADN. The best wavelet packet has a better time-frequency characteristic than traditional wavelet analysis in the different signal processing, because it can extract better and more information from the signal effectively. Based on wavelet packet energy and the neural network, the islanding phenomenon of the ADN can be detected. Firstly, the wavelet packet is used to decompose current and voltage signals of the public coupling point between the distributed photovoltaic (PV) system and power grid, and calculate the energy value of each decomposed frequency band. Secondly, the network is trained using the constructed energy characteristic matrix as a neural network learning sample. At last, in order to achieve the function of identification for islanding detection, lots of samples are trained in the neural network. Based on the actual circumstance of PV operation in the ADN, the MATLAB/SIMULINK simulation model of the ADN is established. After the simulation, there are good output results, which show that the method has the characteristics of high identification accuracy and strong generalization ability.

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Authors and Affiliations

Zhongmei Xi
Faqi Zhao
Xiangyang Zhao
Hong Peng
Chuanxin Xi
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Abstract

In the 1980/1981 breeding season nesting of 9762 pairs of Pygoscelis papua, 59356 pairs of P. adeliae, 302388 pairs of P. antarctica and 1 pair of Eudyptes chrysolophus was observed in the region of King George Island. The greater part of P. antarctica rookeries was located in the hitherto unexplored cliffy coast in the northern part of the island. A hypothesis was set forth that the recent increase in penguin populations was mainly due to the retreat of glaciers and consequently the exposure of new places suitable for breeding sites.

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Authors and Affiliations

Bolesław Jabłoński
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Abstract

Net of temperature, salinity and dissolved oxygen content measurements were made in situ at 24 stations in Admiralty Bay with the use of automatic analyzer Martek MK IV. Results proved a presence of two water masses located horizontally one over the other, with the boundary at depth of 15—35 m. The main, lower mass consists of homogenous waters inflowing from the Bransfield Strait. The upper, thin and much differentiated layer is formed through interaction of the main underlying water mass with meltwaters from glaciers and sea ice. It is probably formed along the whole archipelago and carried by surface currents into the bay where it is subjected to further modifications. Local salinity and temperature extremes are associated with glacier water runoff; local dissolved oxygen maxima seem to be connected with phytoplankton distribution. Strong currents occurring in te bay due to water circulation may cause local, short term and sometimes considerable fluctuations in values of parameters recorded at individual stations.

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Authors and Affiliations

Eduard J. Sarukhanyan
Ryszard Tokarczyk
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Abstract

In the Canary Islands, groundwater is the main source of drinking water. Groundwater mines have been the system used by the engineers of the archipelago to collect water from the ground. The Canary Islands are volcanic with soils characterized by being rich in uranium, the disintegration of which gives rise to radon gas. In this study, radon gas levels in the mines on two islands of the archipelago have been measured to study exposure to this gas in the galleries. Results show values much higher than the European regulatory limit concentrations.

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Authors and Affiliations

Juan C. Santamarta
Luis Enrique Hernández Gutiérrez
Jesica Rodríguez Martín
Lina Pérez
Rafael J. Lario Bascones
Ángel Morales González Moro
Noelia Cruz Pérez
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Abstract

The paper presents the results of field studies carried out in I O chosen forest islands in a suburban area of the town of Jaworzno in the years 1995-2002. Different objects have been studied, among others: natural remnants of oak-hornbeam forest and planted pine-larch woodlots cultivated on the habitat of xerothermic grasslands. In comparison with the total nora of the town, the participation of non-synantropie species and synecological groups associated with natural habitats is much bigger. There are 24 protected species to be found, 40% of protected nora of the town. Despite their diversity, they are precious refugees of many woodland and grassland as well as meadow species occurring within the areas and in their vicinity.
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Authors and Affiliations

Damian Chmura
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Abstract

For many centuries, Upper Silesia was the scene of intensive language contact between a continuum of West Slavic dialects (or the Polish and Czech languages) and German colonists, mainly in the 13th century. The process of colonisation under German town law led to the establishment of hundreds of new towns and villages, some with German names. The oldest historical sources for Upper Silesia are Liber fundationis episcopatus Vratislaviensis (Book of endowments of the Bishopric of Wrocław), dating back to c 1305, as well as registers of such endowments from c 1325. German medieval place names in Upper Silesia are a minority, and no such town names can be found in many areas. This article is an analysis of the percentage of German place names in relation to all place names [in Upper Silesia]. It defines the areas with the largest number of such names and contains a linguistic analysis of the names. Interestingly, the area with the largest number of German place names is the Duchy of Teschen, with the castellany of Oświęcim (which was once part of the Duchy of Teschen), the neighbouring part of the Duchy of Racibórz and the western part of the Duchy of Opole. In the Duchy of Bytom (the Siewierz part of which no longer belongs to Upper Silesia), German place names were not very common. For the areas covered by the Diocese of Kraków, the names of parish priests are known as well. The presence of the German name of parish priests in towns and villages with German place names half a century from their establishment indicates that German people may have lived there, especially because it is certain in some cases that they did.

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Authors and Affiliations

Grzegorz Chromik
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Abstract

The history of Opole Zoological Garden reaches the beginning of the 20th century, when in the Bolko Island, shaped by the Odra river and its canals, the menagerie was founded. Present-day ZOO in Opole is a complex of modern paddocks and structures of an area of around 19 ha, integrated into the old growth of the Bolko Island. In the paper the history and stages of development of Zoological Garden in Opole are presented, the aesthetic and functional values indicated; these ones which make the garden attractive and individual.

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Authors and Affiliations

Monika Ewa Adamska
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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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Authors and Affiliations

Barbara Gumińska
Zofia Heinrich
Maria Olech
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Abstract

Cockburn Island is one of the most historically significant places on the Antarctic continent. The isle was first surveyed in early 1843 during Captain James Ross’ famous expedition, but the early explorers failed to recognise its geological and palaeontological significance. Cockburn Island is exceptional for it has the only succession of Upper Cretaceous, Eocene and Miocene–Pliocene rocks on the continent, which is now known to contain an admirable and diverse fossil record of fauna and flora. These fossil assemblages are providing exciting new information on the evolutionary history of Antarctica. At least 22 species of Late Cretaceous macroinvertebrates and vertebrates have been recognised, whereas the Eocene record is slightly more diverse at 28 macroinvertebrate taxa recorded. The Pliocene macrofossil record is depauperate atsome 11 species, butmicrofossils (diatoms, ostracods, foraminifera) are represented by at least 94 taxa. The palaeoecologic and palaeobiogeographic significance of fossil assemblages is explored in this paper. Further, a checklist of fossils is presented herein, for the first time, as is a bibliography of the geology and palaeontology of the island.

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Authors and Affiliations

Jeffrey D. Stilwell
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Abstract

Nothofagaceae fossil leaves and an associated palynoflora from Late Cretaceous sediments of Vega Island, eastern Antarctic Peninsula, are presented. The leaves are described as Nothofagus sp. 1 and Morphotype LDB 1, and come from the Snow Hill Island (late Campanian-early Maastrichtian) and the López de Bertodano (late Maastrichtian) formations, respectively. The palynoflora obtained from levels immediately above and below the Nothofagus sp. 1 and in the same horizon as the Morphotype LDB 1, included terrestrial and marine elements. In the palynoflora associated with Nothofagus sp. 1, conifers are dominant and pollen grains with Nothofagus affinity are represented by four species: Nothofagidites kaitangataensis (Te Punga) Romero 1973 and Nothofagidites senectus Dettmann and Playford 1968, which belong to the ancestral pollen type, as well as Nothofagidites dorotensis Romero 1973 and Nothofagidites sp. of the brassii-type. Cryptogamic spores, marine dinoflagellate cysts and algae, among others, are part of the assemblage. The palynoflora associated with the Morphotype LDB 1 also contains abundant conifer and angiosperm pollen grains with N. dorotensis as the only Nothofagus species recorded. Marine dinoflagellate cysts are scarce while fungi and phytodebris are common elements. The joint presence of marine and non-marine palynomorphs supports a probable nearshore environment at time of deposition for both units. Pollen and spore evidence suggests a mixed conifer and angiosperm forest, with Podocarpaceae and Nothofagus as the main components, and ferns, lycopods, and mosses in the understory. This forest developed under temperate and moist conditions during the middle Campanian-Maastrichtian.

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Authors and Affiliations

Edgardo Romero
Cecilia R. Amenábar
María C. Zamaloa
Andrea Concheyro
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Abstract

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.

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Authors and Affiliations

Anna Jażdżewska
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Abstract

Here are reported the first certainly indigenous agglutinated foraminifera known for the Eocene La Meseta Formation on Seymour Island, West Antarctica. The specimens were identified as Textularia sp. and occur in the upper portion of the unit, just below the contact with the overlying post-Eocene deposits. Despite being rare, the specimens are interpreted as autochthonous or parautochthonous due to their overall good preservation, fragility, and lack of sedimentary filling. The La Meseta Formation seems to have passed through a major diagenetic dissolution of calcareous microfossils, but the present findings suggest that indigenous agglutinated foraminifera can be found at least in some of its strata.

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Authors and Affiliations

Victor C.S. Badaró
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Abstract

Properties of a snow cover in the vicinity of Arctowski Station, King George Island (West Antarctica) were studied in 1991. Variations of snow quality and physical transformations were analysed against changes of atmospheric parameters, basing on water equivalent index and repeatable examination of snow pits. Essential dependence of snow cover distribution and snow structure from local climatic features and terrain morphology was found. Thawing occurs in the whole mass of snow, with its contribution of both liquid and gas water phases.

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Authors and Affiliations

Przemysław Gonera
Grzegorz Rachlewicz
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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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Authors and Affiliations

Claudia P. Tambussi
Jorge I. Noriega
Andrzej Gaździcki
Andrzej Tatur
Marcelo A. Reguero
Sergio F. Vizcaino
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Abstract

Mineral composition of bedrock is the main factor determining salt mineralization in the weathering zone of Seymour (Marambio) Island (maritime — Antarctic continent climatic boundary). Supply of salts by sea water spray can accelerate weathering process, modify chemical formula of salt minerals and give ephemeral efflorescences of easy soluble chlorides and partially longer lasting gypsum on the surface. Microbiologically mediated oxidation of sulphides and followed acid sulphate drainage formed K and Na jarosite, basic amorphous aluminium sulphate, gypsum, aluminium bearing ferrihydrite and ankerite in weathering zone of Paleogene sediments. Intense alteration of well-lithified, calcareous sandstones of unit 1 of the López de Bertodano Formation (Cretaceous) on old erosion surface led localy to surface mineralization comparable with that found in Antarctic Continent. Stones laying on the soil surface are covered by thin red film of ferrihydrite above the soil level and by light green crust of aragonite coloured by glauconite pigment on the underground side. Most of the Cretaceous sediment does not contain sulphides nor alteration susceptible silicates thus ephemeral sea salts efflorescences observed on its surface are more prominent than in another places.

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Authors and Affiliations

Andrzej Tatur
Andrzej Barczuk
Rodolfo del Valle
Ronald Sletten
Ewa Kicińska
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Abstract

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.

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Authors and Affiliations

Katarzyna J. Chwedorzewska
Małgorzata Korczak
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Abstract

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.

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Authors and Affiliations

Wojciech Majewski
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Abstract

Three lichenized fungal species collected from James Ross Island (eastern coast of Antarctic Peninsula): Cladonia acuminata (Ach.) Norrl., Rhizocarpon pusillum Runemark and Rhizoplaca parilis S.D. Leav., Fern.-Mend., Lumbsch, Sohrabi et St. Clair are reported from Antarctica for the first time. Detailed morphological and anatomical properties of these species along with photographes based on Antarctic specimens are provided here. In addition, the nrITS gene regions of the selected specimens are studied and the phylogenetic positions of the species are discussed. The nrITS data for Rhizocarpon pusillum is provided for the first time. According to our studies the lichen biodiversity of the Antarctic is still poorly known and molecular studies are very important in order to present the correct lichen biodiversity of Antarctica.
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Authors and Affiliations

Mehmet Gökhan Halici
1
ORCID: ORCID
Merve Kahraman
1
Osman Osmanoğlu
1
Milos Bartak
2

  1. Department of Biology, Faculty of Science, Erciyes University, 380 39 Kayseri, Turkey
  2. Department of Experimental Biology, Section of Plant Physiology, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
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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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Authors and Affiliations

Piotr Jadwiszczak
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Abstract

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.

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Authors and Affiliations

Wojciech Majewski
Ewa Olempska
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Abstract

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.

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Authors and Affiliations

Krzysztof Birkenmajer
Andrzej Gaździcki
Krzysztof P. Krajewski
Andrzej Przybycin
Andrzej Solecki
Andrzej Tatur
Ho Il Yoon
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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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Authors and Affiliations

Marcela M. Libertelli
Nestor Coria
Germán Marateo
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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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Authors and Affiliations

Andrzej Gaździcki
Wojciech Majewski
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Abstract

In the Admiralty Bay 36 taxa of macroalgae were found. Among them the most common were: green alga Monostroma hariotti, red algae — Georgiella confluens, Iridaea cordata, Leptosarca simplex and Plocamium cartilagineum, and brown algae — Adenocystis utricularis, Ascoseira mirabilis, Desmarestia anceps, D. ligulata, D. menziesii and Himatothallus grandifolius. The bottom surface covered with macroalgae (in the orthogonal projection on the water mirror) amounts to 36,9 km2 i.e. 31% of the total surface of the bay. In the central part of the Admiralty Bay the macroalgae aggregations occupy 35% of the bottom surface and are most abundant in respect to the density, biomass, number of taxa (33) and diversity. There were distinguished 3 zones of vertical distribution of phytobenthos in the Admiralty Bay. I zone includes the macroalgae in epilittoral, littoral and sublittoral to the depth of 10 m. II and III zones are situated in sublittoral within the depths of 10 60 m and 60—90 m, respectively. Each zone is characterized by the occurrence of different aggregation of taxa. The bottom areas belong to I, II and III zone of macroalgae make 28%, 64% and 8% respectively in relation to the total surface of phytobenthos in the bay. Vertical range of the distinguished zones varies in different parts of the Bay in relation to the bottom character. Macroalgae occur down to the depth of 90 —100 m. The composition of the macroalgae flora evidences for its transitory character between the benthic subantarctic flora and that of the areas adjacent to the Antarctic continent.

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Authors and Affiliations

Krzysztof Zieliński
ORCID: ORCID

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