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Number of results: 36
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Abstract

The influence of Lindane on net phytoplankton (mainly diatoms) in samples of waters from the Antarctic was investigated for 24 hours from the introduction of ɣ HCH 0,02 and 2 ppm into the environment. Changes in intensity of 14C incorporation in the light and in rate of release of 14C by the cells in the dark during consecutive light/dark periods were measured. The effect of two different Lindane concentrations in diatoms occurred 16 hours after introduction of the compound into the environment and was independent of concentration. The effect was manifested by delayed induction of photosynthesis following the dark period and also by changes in dynamic equilibrium between carbon assimilation and dissimilation. The presence of Lindane clearly stimulated 14C incorporation in the light and also enhanced the participation of 14C incorporation in overall CO2 exchange in the dark.
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Abstract

Phytoplankton samples were collected at 62 stations in the European Arctic Seas and the Faroe — Shetland Islands area. Over 30 species of dinoflagellates were found. 22 species are illustrated by original drawings. The data on synonyms, size or size variability on the distribution and environmental factors (temperature and salinity) are given.
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Abstract

This paper reports on 29 species of lichenicolous fungi collected in the Hornsund region and Sørkapp Land area, Spitsbergen. New to science are Hystrix gen. nov., Slellifraga gen. nov., Dactylospora cladoniicola sp. nov., Hystrix peltigericola sp. nov., Stellifraga cladoniicola sp. nov. and Zwackhiomyces macrosporus sp. nov. A further 15 species are new to Svalbard.
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Abstract

Eight samples of the ice algae were collected from the annual ice in Tikhaia Bay, Hooker Island, Franz Josef Land. Species composition included 58 diatoms (and some Navicula, Nitzschia and other Pennatophyceae unidentified species), 2 dinoflagellates, 2 chrysophyceans, 1 chlorophycean, 1 cyanophycean and possible dinoflagellate and chrysophycean cysts. The maximum quantity was 132300 cells/l. In 4 samples Aulacoseira granulatu prevailed, in other samples Nitzschia frigida, N. cylindrus, Rhizoclonium sp. and dinoflagellate cysts dominated. Xanthiopyxis polaris found by Gran (1904) in Arctic sea ice and referred to the diatoms is, possibly, the dinoflagellate cyst. On the whole, the ice community consisted of benthic and planktonic-benthic species of mainly marine and brackishwater-marine pennate diatoms, their resting stages, freshwater unicellular algae and marine chlorophycean.
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Abstract

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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Abstract

The list of shallow—water molluscs: chitons (2 species), gastropods (33 species) and bivalves (36 species) of Isfjorden is presented. Distribution, frequency and domination structure are discussed and zoogeographical analysis is presented.
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Abstract

In 1989/90, in the region of SSSI 8 situated on King George Island 21 bird species were observed, 12 species were breeding. Dominants were 3 Pygoscelis species (19229 pairs). Five species of pinnipedians were noticed. Mirounga leonina was most abundant in January (623 individuals), Arctocephalus gazella — in February and March (890 individuals), Hydrurga leptonyx in October (39 individuals). The abundance of Leptonychotes weddelli was low and rather stable. As a result of mild winter during the study period such birds as Sterna vittata and Pygoscelis adeliae stayed near their breeding places. The scarcity of Lobodon carcinophagus was probably also a result of this mild winter.
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Abstract

Materials used in this work were collected during BIOM ASS - SIBEX project in the Drake Passage and the Bransfield Strait (1983/1984) in three water layers: 0 - 100 m, 100 — 300 m and 300—500 m. Four species of Chaetognatha were found: Eukrohnia hamata and Sagitta gazellae in both water regions; Sagitta planctonis occurred mainly in the Drake Passage whereas Sagitta marri was noted in the Bransfield Strait and adjacent parts of the Bellingshausen and Scotia seas. Chaetognatha were most numerous in the Drake Passage and generally in the layer 100 — 300 m. Vertical distribution of Chaetognatha was clearly influenced hydrological conditions.
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Abstract

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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Abstract

Physical and chemical properties (granulometric composition, pH, carbonates, organic carbon, nitrogen etc.) as well as bioenergetic activity of Spitsbergen tundra soils were studied at three chosen stations situated near Polish polar station "Hornsund". It was found that biological activity of Arctic tundra soils depended mainly on its physical properties, whereas the chemical composition of organic matter did not effect directly the bioenergetics of these soils. This bioenergetic activity depends mainly on the richness of micro- and mesofauna communities inhabiting the soil.
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Abstract

The paper deals with the structural variability and generative reproduction of Saxifraga oppositifolia populations in eight localities situated in Western Spitsbergen. The localities differed in terms of humidity, soil fertility, microclimate and frequency of disturbances. The population structure, the growth and development rate of individuals in the sea terrace and at the peat-bog prove that a dense plant cover influences positively the development of S. oppositifolia. The size of individuals, their biomass and population density is limited in most of the studied localities. Solifluction is the factor influencing the development of a population to the greatest extent. Of all the researched populations the weakest development was observed in the active structural grounds. Yearly changes in the structure of the populations as well as the yearly growth of the species studied are limited. The longevity, the development rate and size of the seedling recruitment are subject to modifications caused by the solifluction.
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Abstract

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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Abstract

In the material collected in 26 stations along the course of three creeks in the vicinity of Polish Antarctic Station 183 taxa of algae have been identified: 25 of Cyanophyta, 123 of Bacillariophyceae, 2 of Xanthophyceae, 2 of Chrysophyceae and 31 of Chlorophyta. The highest species diversity was found in the algal community in Creek II (132 taxa), the second place was occupied by the "Petrified Forest Creek" (97 taxa), and the least diversified algal community was that from the "Ornithologists' Creek" (73 taxa).
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Abstract

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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Abstract

Flying bird counts were carried out at Esperanza Bay (62°24'S, 56°59'W), Antarctic Peninsula, between November 1989 and February 1990. Six breeding species (Oceanites oceanicus, Chionis alba, Catharacta lonnbergi, Catharacta maccormicki, Larus dominicanus and Sterna vittata) and six visitor species (Macronectes giganteus, Fulmarus glacialoides, Daption capense, Pagodroma nivea, Fregetta tropica and Phalacrocorax atriceps) were recorded. Kelp gull and Antarctic tern populations have decreased in relation to the data by previous authors, perhaps as a result of the increased activity at Esperanza Station. Cygnus melanocoryphus was recorded for the first time at Esperanza Bay.
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Abstract

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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Abstract

Phytoplankton samples were collected at 74 stations in the European Arctic seas, 28 species of the armoured din oft age Hates being found. Thirteen dinoflagellates are illustrated by original drawings. The data on synonyms, size or size variation, localities and environmental factors (temperature and salinity) at the surface are given.
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Abstract

Chlorophyll α, phytoplankton, suspensions and zooplankton beneath the fast ice have been studied in Spitsbergen fjords (Hornsund, Bellsund, Sassenfjord, Gronfjord and Kongsfjord) in 1982, 1984/85,1987 and 1988. Observations on ice associated Polar cod and wildlife have been collected simultaneously. There were no typical sympagic communities observed at the West Spitsbergen fast ice. Exception was spring 1982 and 1988 when drifting ice from Barents Sea contributed to the fjords fauna. Fast ice on the investigated fjords was poor in adjacent zooplankton (biomass below 0.06 g/m3). Ice phytoplankton reflects the autumn situation and no specific communities of algae have been found. Chlorophyll α amount and organic sedimentation from ice and from the adjacent water were very similar (0.4 to 1.7 mg/m3 chlorophyll and 8 to 10 g d.w./m2/day sedimenling matter). The diet of Polar cod reflected the food items occurrence, Calanus has been the most common food. N o specific concentration of seabirds have been observed at fjords ice.
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Abstract

Attempt of correlation of raised marine beaches and glacial episodes in West Spitsbergen is presented for the Middle and the Late Quaternary. A model of predominating Barents Sea shelf ice sheet during the Saalian and of co-existing distinct local ice domes during the Vistulian is postulated on the basis of varying land uplift. Glacial episodes in Spitsbergen are referred to the ones in continental Europe and North America. Rough prognosis of climatic trends is introduced.
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Abstract

Geological and geomorphological studies in Kaffiöyra and Hermansenöya (Oscar II Land, northwestern Spitsbergen), completed with radiocarbon datings, indicated that the Early Vistulian (Weichselian) Glaciation of presumable regional significance, occupied the whole area. Marine transgression during and after deglaciation reached at least to 65 m a.s.l. Glacioisostatic uplift and marine regression in Kaffiöyra resulted in development of older raised beaches at 52-65 m a.s.l. During the Late Vistulian, Kaffiöyra was occupied partly by outlet glaciers (Aavatsmark, Elise and Andreas), while the Dahl Glacier covered Hermansenöya. Extents of these glaciers were much greater than during the Little Ice Age. Marine transgression during deglaciation reached to 46-48 m a.s.l. at about 12-11.5 ka B.P. During glacioisostatic emergence at 11.5-9 ka B.P., ten younger raised marine beaches were formed in Kaffiöyra. Traces of a probable glacial episode at 3-2.5 ka B.P. were noted in forefields of the Aavatsmark and the Elise glaciers only. In forefields of all glaciers in Kaffiöyra there are deposits and landforms formed during glacial advances of the Little Ice Age and the following continuous retreat. The Aavatsmark Glacier was the only one to indicate surge type readvances at that time.
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Abstract

Relief of Svalbard is an effect of varied morphogenetic, exogenic and endogenic processes. Tectonic and glacioisostatic movements of the Earth crust have occurred many a time in this region. Glacial, marine and periglacial features are particularly common. During the Late Quaternary the western Nordenskiöld Land underwent several sea transgressions, followed by glacier advances. Basing on erratics of crystalline rocks transported by sea ice, past sea levels have been established up to 250 m a.s.l. Marine terraces above 60 m a.s.l. date back to the Late Pleistocene, the lower ones are of the Holocene age.
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Abstract

Studies of the Quaternary evolution of the Hornsund Region in Spitsbergen focused in nine key areas, in which detailed fieldworks with mapping and sampling to radiocarbon and thermoluminescence analyses have been done. Glacial history of the Hornsund Region is known from the Torellkjegla (Holsteinian) Interglacial up to the recent times. The Wedel Jarlsberg Land (Saalian) Glaciation was the most widespread in this part of Spitsbergen and consisted of two stades(?). It was followed by considerable glacier retreat during the Bogstranda (Eemian) Interglacial, the latter being represented by development of soils. Four glacier advances (the two younger ones are the Lisbetdalen and the Slaklidalen stages) occurred during the Sörkapp Land (Vistulian) Glaciation. Three glacier advances (Gronfjorden and Revdalen stages, followed by the Little Ice Age) were recognized for the Holocene. The oldest and highest (although somewhat questionable) raised marine beaches come presumably from the Wedel Jarlsberg Land Glaciation. The beaches 80-100 m a.s.l. were formed during the Bogstranda (Eemian) Interglacial. The beaches 20-60 m a.s.l. are correlated with the Sórkapp Land Glaciation. All the lower marine beaches were formed during the Holocene.
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