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Abstrakt

The distribution of planktonic Ostracoda (Halocyprididae) was studied based on vertically-stratified zooplankton samples collected by hauling 200 p.m - mesh net by day and by night during two austral seasons: summer 1985/1986 and winter 1989, from the 1200 m deep Croker Passage off the Antarctic Peninsula. Seven species of Ostracoda were recorded: Alacia belgicae, Alacia hettacra, Melaconchoecia isocheira, Metaconchoecia skogsbergi, Boroecia antipoda, Disconchoecia aff. elegans and Proceroecia brachyaskos. The first three species, endemic to Antarctic waters, were predominant (about 90%). Generally Ostracoda were most numerous in 600-200 m layer in summer and in 1000-400 m layer in winter. In the investigated area there was a clear contrast between the abundance of Ostracoda during austral summer and scarcity during austral winter.
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Abstrakt

226 papers by Polish authors and co-authors have been collected. They deal with Antarctic or sub-Antarctic fishes and also their parasites. The majority (35.7%) of the publications discuss fish biology including growth, age, maturity, feeding and occurrence of particular species in the area. Fewer papers are devoted to parasitology (26.0%). Papers dealing with fish biomass and exploitation make up 18.5%. Papers dealing with morphology and systematics make up 6.6%. The remaining papers are devoted to technology, physiology, palaeontology and others.
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Słowa kluczowe Antarctic krill parasites

Abstrakt

The highest infestation by phoronts (resting stages) of Apostoma ciliates forms 1, 2, is restricted to the 3-th and 4-th pairs of E. superba thoracic limbs. They occur mostly on meropodites of endopodite and plumose setae of exopodite. The trophonts (trophic stage) of those Apostoma are present in large numbers in krill's tissue. The life cycle of those histophagous Apostoma include also free-living stage - tomit. Swarm formed by krill seems to be a reason for the common and extensive infestation by protozoans.
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Słowa kluczowe Antarctic parasitic isopods

Abstrakt

Parasitic isopods (Aega antarclica and Gnathia calva) were discovered on fishes collected during Polish expeditions to the Atlantic sector of the Southern Ocean. Pranizae of G.calva infected 14.5% of Nololhenia corriceps neglecta and 16% of Notothenia rossi marmorata. The infestation rates are probably underestimated.
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Abstrakt

During austral summer phytoplankton is the main component of food of E. superba postlarval stages. Diatomeae: Thalassiosira spp., Nitzschia spp. and tiny Pennatae constitue 98% of all consumed food particles. 91% of algae consumed were of 8—40 μm, and their mean size is 21.4 μm. The mean amount of algae found in of Euphausia superba was about 1700 per individual. The differences in species composition and the size of algae eaten by juvenes, preadult and adult individuals decrease the food competition between particular age groups of E. superba.
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Abstrakt

The list contains original papers by Polish authors or co-authors concerning Antarctic or sub-Antarctic plants. The list is supplemented by papers on bacteria and those on general indicators of the amount of plants (chlorophyll content and primary productivity). Antarctic investigations of Polish botanists were carried out mainly during the expeditions to Polish Antarctic Station "H. Arctowski" (King George Island, South Shetlands; 62° 09'S, 58° 28'W) founded 1977 as well as during Polish oceanic expeditions of the BIOMASS project (1981, 1983-1984, 1986-1987) and studies of the ice-edge zone (1988-1989) carried out in the Atlantic sector of Southern Ocean on board of the r/v "Profesor Siedlecki". All these expeditions were organized by the Department of Polar Research, Institute of Ecology, Polish Academy of Sciences headed by Prof. Dr. S. Rakusa-Suszczewski.
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Abstrakt

Traps to catch microfauna transported by wind were installed on already colonised by plants area, in the vicinity of the glacier. After 6-week-exposition 859 individuals of microfauna were caught, of which Nematoda constituted 71%, Tardigrada 22% and Rotifcra 7%. Number of microfauna individuals caught depended on distance from the already colonised areas and presence of plant parts, together with which animals can be transported more easily. Microfauna connected with vegetation, which is transferred together with plant parts, was transported in higher numbers. Probably these taxa (i.e. Diphascon within tardigrades and Dorylaimidae within nematodes) colonise new habitats at first, but other species dominate later in freshwater bodies.
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Abstrakt

In material collected from birds (Aves, Procellariiformes) in the South Georgia region by Polish Antarctic Marine Research Expedition in 1976 the following mallophagan species were found: Docophoroides brevis (Duf.), Naubates fuliginosus (Tasch.), Pseudonirmus gurlti (Tasch.) and Trabeculus hexacon (Wat.). These are the first records from this region.
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Abstrakt

Lipolytic activity was assayed in samples of Antarctic krill frozen in different conditions and in its liquid digesta with synthetic (tributylglycerol, esters of 2-naphtol and fatty acids C3, C9 , C14 and C18 ) and natural (olive oil) substrates. It was testified that the lipolytic activity is several-fold higher in the crustaceans with high food intake than in those with an empty digestive tract. Krill lipases show higher activity against esters of unsaturated fatty acids that against analogous derivatives of saturated ones and 10-fold higher affinity tributylglycerol (Km = 1.12 mM). Their maximal activity is at pH 6.4 and 37°C. E. superba lipases preserve total activity up to 35°C for 45 minutes, and are completely inactivated at 55°C for 5 minutes. Prevailing part of lipolytic activity is present in krill cephalothorax, however, extracts from krill abdomen also display a marked activity. Krill lipases are probably resistant to an attack of crustacean's proteinases.
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Słowa kluczowe Antarctic plants fungi

Abstrakt

This paper recapitulates Polish botanical and mycological research on terrestrial and freshwater Antarctic ecosystems carried out between 1977 and 2009. The main results are briefly summarized. The references encompass nearly 200 papers on floristics, taxonomy, biogeography, ecology, cytology, bioc hemistry, physiology and genetics of lichens, mosses, fungi, algae and vascular plants inhabiting soils, rocks and inland waters in the Antarctic.
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Abstrakt

104 specimens of notothenioid fishes of five species (Patagonotothen longipes, P. tessellata, Champsocephalus esox, Cottoperca trigloides and Patagonotothen brevicauda) caught at two sites in the Beagle Channel (Magellanic sub-region, sub-Antarctica) were examined for the presence of thorny-headed worms (Acanthocephala). Representatives of three fish species, Patagonotothen longipes, P. tessellata, and Champsocephalus esox, were infected. Fishes caught at the eastern mouth of the channel were infected with 180 echinorhynchids representing three species, Aspersentis johni (the most numerous species), Heterosentis heteracanthus, and Hypoechinorhynchus magellanicus, and only 12 cystacanths of four polymorphids, Andracantha baylisi, Corynosoma sp., Corynosoma beaglense, and Corynosoma evae. Patagonotothen longipes was the most highly infected in the eastern mouth of the channel (prevalence 85%, maximum intensity 26). Aspersentis johni was the dominant parasite species in this host (prevalence 85%, mean abundance 4.00, maximum intensity 18) and H. heteracanthus was the sub-dominant one (prevalence 50%, mean abundance 2.60, maximum intensity 25). The infections of C. esox were the most diverse (six parasite species - three echinorhynchids and three polymorphids). Fish caught near the city of Ushuaia were infected only with six cystacanths of C. evae (intensity one). Taking into account the whole sample, C. evae was the most abundant polymorphid, represented by 10 of 18 specimens found. Three species, H. heteracanthus, A. baylisi and C. evae, have been previously reported from the low western Antarctic (H. heteracanthus also from the Kerguelen sub-region of sub-Antarctic), remaining four species seem to be endemics of the Magellanic sub-region of sub-Antarctic.
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Abstrakt

In the material of nearly 2000 individuals of Asteroidea collected in Admiralty Bay, the largest bay of the South Shetlands, 36 species were determined, enriching the list of hitherto known asteroid species of this basin by 17 taxa. One of them, Peribolaster macleani, is recorded for the first time in Western Antarctic. The most frequent and abundant asteroids of Admiralty Bay were Odonlaster validus, Psilaster charcoti, Bathybiaster loripes obesus and Diplasterias brucei. The bathymetric and geographic distribution of all species are discussed.
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Abstrakt

Polish exploration and exploitation of marine resources of Antarctic waters date back to the reconnaissance cruise of the Sea Fisheries Institutes (SFI) r/v Profesor Siedlecki in 1974. Since 1975, a co-operation between the Institute of Ecology, Polish Academy of Sciences (PAS) at Dziekanów Leśny and SFI in Gdynia with participation of the University of Agriculture in Szczecin, Faculty Marine Fisheries and Food Technology (UA) was established. Fishing fleets of the Polish Deep-Sea Fisheries Companies Odra, Dalmor and Gryf, since 1976 were operating in the Atlantic sector of Antarctic waters, south of the convergence.
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Abstrakt

A collection of 15 283 individuals of tanaidacean crustaceans was gathered by successive Polish Antarctic Expeditions in the years 1977-1993 in Admiralty Bay (King George Island, South Shetland Islands). Twelve species belonging to three families are identified in this study. The material is clearly dominated by Nototanais antarcticus (Hodgson, 1902); other common species were Nototanais dimorphus (Beddard, 1886) and Peraeospinosus sp. A. The highest density of tanaids was over 140 000 specimens m-2 , occuring on a muddy bottom in Herve Cove lagoon.
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Abstrakt

Results of Polish biological investigations and surveys on the state of mackerel icefish (Champsocephalus gunnari Lonnberg, 1905) stock served to undertake an attempt at an independent estimation of some of its biological parameters as well as at the assessment of its biomass and fishing mortality during 1975/76—1991/92 fishing seasons with virtual population analysis (VPA) method (using MAFFVPA programme). Laurec-Shepherd and hybrid methods were applied for the VPA tuning. Von Bertalanffy equation parameters were estimated and compared with those published earlier. F0l and F max values were assessed using Beverton and Holt model and Thompson and Bell method. Based on data from available literature the coefficient of natural mortality (M) was assumed to be 0.5. VPA results indicate that the total stock biomass (TSB) during the last 1991/92 season amounted to 34,818 tonnes and was approximately 10 times lower than in 1975/76 season. Spawning stock biomass (SSB) declined to a minimum of 7,396 tonnes in 1989/90 season. The assessment results point out to the recruitment as a major factor contributing to the stock fluctuations.
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Abstrakt

Pinnipeds were monitored in Admiralty Bay between 1988 and 1992. No particular trends during this period were found, but seasonal changes in each are distinct. It is suggested that the phenology of pinnipeds and that of penguins ensures low competition for food between these groups.
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Abstrakt

A new genus and species of heteronemertean from the Antarctic (Bellingshausen Sea), Oligodendrorhynchus hesperides , is described and illustrated. Some morphological features with major systematic significance are following: the mode of branching of the proboscis and its low number of terminal branches; the lack of horizontal lateral cephalic slits but in their place a pair of shallow epidermal depressions; a gelatinous amorphous connective stratum between the outer longitudinal and circular muscle layers; the presence of a rhynchocoelic nerve; isolated fibres of the rhynchocoel circular muscle layer interwoven with bundles of the adjacent body−wall inner longitudinal muscle fibres in the intestinal region. Other anatomical characters which can also be used to distinguish the new taxon from existing heteronemertean species that have a branched proboscis are also discussed.
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Abstrakt

A new species of lichenized ascomycete, Massalongia olechiana Alstrup et Søchting, sp. nov. (Massalongiaceae) is described from the South Shetland Islands and the Antarctic Peninsula. The species is distinguished by laminal isidia and 5–7−septate ascospores. The relationships with the other species of the genus are discussed. From Massalongia carnosa , recorded from both the Arctic and the Antarctic, the new species is distinguished by its lack of isidioid squamules and in having pluriseptate ascospores instead of 1−septate ascospores
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Abstrakt

During three austral summer seasons, dust and soil from clothes, boots and equipment of members of scientific expeditions and tourists visiting the Polish Antarctic Station Henryk Arctowski were collected and analysed for the presence of fungal propagules. Of a total of 60 samples, 554 colonies of fungi belonging to 19 genera were identified. Colonies of the genus Cladosporium , Penicillium and non−sporulating fungus ( Mycelia sterilia ) dominated in the examined samples. The microbiological assessment of air for the presence of fungi was also conducted at two points in the station building and two others outside the station. A total of 175 fungal colonies belonging to six genera were isolated. Colonies of the genus Penicillium were the commonest in the air samples. The potential epidemiological consequences for indigenous species as a result of unintentional transport of fungal propagules to the Antarctic biome are discussed in the light of rapid climate change in some parts of the Ant − arctic and adaptation of fungi to extreme conditions.
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Abstrakt

There are hardly any data concerning the vertical micro−distribution of protozoa in water column in cryoconite holes on the glacier surface. Such comparisons can provide insights into the ecology of protozoa. The present research was made on Ecology Glacier (South Shetland Islands, Antarctic); vertical microzonation of c iliates in relation to physical and chemical parameters in cryoconite holes was studied. The density and biomass of protozoans significantly differed between the studied stations (cryoconite holes), with the lowest numbers in the surface water and the highest in the bottom water. The surface waters were dominated by mixotrophic and omnivorous taxa, whe reas the deepest sampling level has shown the increase of the proportion of bacterivore species . Ordination analysis indicated that TN and P−PO 4 can strongly regulate the abundance and species composition of protozoa. The redundancy analyses (RDA) showed that the ciliate communities can be separated into two groups. The first group included species associated with surface water: Halteria grandinella and Codonella sp. The second group included species that are associated with bottom water: Prorodon sp. , Holosticha pullaster , Stylonychia mytilus −complex and small scuticociliates.
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Abstrakt

Nematoda, Tardigrada, Rotifera and Crustacea composition in different freshwater habitats on Spitsbergen (Arctic) and King George Island (Antarctic) was presented. In all surveyed groups more genera and species were recorded from Spitsbergen than from King George Island. Habitats richest in taxa were moss banks and thaw ponds, whereas streams were poorest in species. In all groups in both regions cosmopolitan species dominated, but higher number of endemic species was recorded on King George Island. Regarding species composition in surveyed groups it can be suggested that freshwater habitats on Spitsbergen are more similar to each other than those on King George Island.
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Abstrakt

Net phytoplankton cell numbers in 50 m water column of Admiralty Bay ranged between 0.2 x 10 5 x m-2 on 24 August 1990 and 2.3 x 10 7 x m-2 on 15 November 1990. Cluster analysis has confirmed the presence of two groups of samples: spring and summer ones (October to April), rich in cells and in species, and, on the other hand, winter samples (June to August) impoverished in algae. Spring and summer fluctuations of diatoms were mainly due to Corethron criophilum, Rhizosolenia alata and its varieties, R. hebetata f. semispina, Thalassiosira spp., Chaetoceros spp., and Nitzschia spp. (Fragilariopsis and Pseudonitzschia groups). The abundance and succession of species in Admiralty Bay reflect seasonal differences in diatom growth; they also reflect mixed populations of the Weddell and Bellingshausen seas entering Admiralty Bay via Bransfield Strait. Striking poverty of algae in some summer samples can most likely be attributed to zooplankton grazing.
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Abstrakt

Herve Cove, a small, shallow and partly isolated basin, is strongly influenced by glacial freshwater inlfow, bringing significant amount of mineral suspension. Its mean annual content amounted up to 46 mg dm-3. Sea anemone (Edwardsia sp.), bivalves (Yoldia eightsi, Laternula elliptica and Mysella sp.), amphipods (mostly Cheirimedon femoratus) a well as some species of polychaetes constituted almost 95% of zoobenthos biomass and 90% of abundance. Four different assemblages of benthic invertebrates, with total biomass ranging from 0.002 kg m-2 up to 1.7 kg m-2, were distinguished in this relatively small (about 12 ha) area. It seems that the freshwater impact influences the composition of an assemblage occurring close to the edge of a glacier. Relatively rich crustacean fauna was encountered in the shallow part of the cove near its entrance. Almost complete lack of echinoderms in Herve Cove, that are common in the shallow Antarctic sublittoral, should also be noted. Macrozooplankton of Herve Cove was dominated by Copepoda. The most frequent and abundant species were: Oithona similis, Ctenocalanus citer and Metridia gerlachei. Far less numerous Chaetognatha represented by three species, Ostracoda, Polychaeta, Pteropoda and Siphonophora constituted only 2.5% of all planktonie animals collected.
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Abstrakt

Some 20 samples of bottom sediments of freshwater lakes collected in the Antarctic Thala Hills oasis (Enderby Land) were soaked in laboratory cultures. 85 taxa of algae were identified in these cultures: Cyanophyceae — 54, Chrysophyceae — 1, Xanthophyceae 10 and Chlorophyceae — 20 taxa. Most of these taxa are illustrated.
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Abstrakt

Thermoregulation is fully developed in 5 day old Wilson's storm petrels Oceanites oceanicus (Kuhl). Resting metabolic rate (RMR) and body temperature (Tb) of unattended 1- and 3-day old chicks continuously decrease at ambient temperature (Ta) of 5°C. After being heated the chicks return to normothermia. Ability to survive temporal deep hypothermia seems to be an adaptation to absence of parents and low temperatures in the nest during first days of life. After snow storm, during two days of starvation, chick RMR decreases by 40% at Ta of 0°C, but chick Tb is stable. This suggest decrease of thermal conductance (Ct). Fall of Ct may suggest beginning of hypohermia.
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