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Number of results: 30
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Abstract

he paper contains results of a in situ research main task of which was to detect objects buried, partially or completely, in the sea bottom. Object detecting technologies employing acoustic wave sources based on nonlinear interaction of elastic waves require application of parametric sound sources. Detection of objects buried in the sea bottom with the use of classic hydroacoustic devices such as the sidescan sonar or multibeam echosounder proves ineffective. Wave frequencies used in such devices are generally larger than tens of kHz. This results in the fact that almost the whole acoustic energy is reflected from the bottom. On the other hand, parametric echosounders radiate waves with low frequency and narrow beam patterns which ensure high spatial resolution and allows to penetrate the sea bottom to depths of the order of tens of meters. This allows to detect objects that can be interesting, among other things, from archaeological or military point of view.
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Abstract

Altogether 105 algal taxa were identified including 101 diatom species. Chaetoceros criophilus was dominant in the western part of the study area influenced by waters from the Bellingshausen Sea. Corethron criophilum was abundant in the Weddcll Sea water mass found to the east of 53.5°W meridian. Nitzschia cylindrus common in the ice-melt samples was dominant in only two net phytoplankton collections obtained at the ice-edge zone. Additional samples from Admiralty Bay, at King George Island revealed the dominance of Chaetoceros socialis and the presence of many tychoplankton species. Very few diatom cells were found in the open waters of the Bransfield Strait which combined with the presence of krill, suggested intensive grazing by herbivores. The unstable waters of the Weddell-Scotia Confluence area contained little phytoplankton except for a station dominated by Phaeocystis pouchetii. Greater cell densities were related to warm, lower salinity Weddell Sea water of summer modification found in the surface layer east from 49°W.
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Abstract

The article presents a review of the researches on sea and atmospheric physics conducted by the Polish expeditions in Antarctica from 1977 to 1990.
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Abstract

Results of an oceanographic survey along the edge of drifting pack ice in the area between Elephant Island and the South Orkney Islands are reported. The influence of sea ice on hydrological factors was very weak. It was not possible to develop oceanographic features characteristic for marginal sea-ice zones in the areas with well marked surface currents and dynamic hydrological conditions. The spatial distribution of chlorophyll was governed by water stability, although during our survey, areas with enhanced vertical stability could not be described in terms of a sea-ice edge influence.
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Abstract

The highest concentrations of algal cells (1.1 x l0 6 litre- 1 ) and of algal carbon (20 μg litre -1 ) were associated with a lens of ice melt water in the northeast of the study area. Phytoflagellates were dominant at all stations with greater numbers always in the 0 - 20 m surface layer and with the peaks of Cryptophyceae in the open waters and also near the ice edge east of 50° W. Picoplankton flagellates and monads (1.5-5.0 μ) were generally next in abundance and most important numerically in the near ice stations in the western part of the study area. Parasinophyceae were usually more abundant than Nitzschia cylindrus (Grunow) Hasle, the only common diatom species found mainly in the western near ice edge stations. The presence olN.cylindrus, dominant in the pack ice and in phytoplankton near the ice edge, shows that algae released from ice may act as an inoculum for the phytoplankton.
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Abstract

The Author tries to “think out of the box”, presenting “Sponsalia ex hoc mundo” (“Hand fastening out of this world”). The title reflects the view that the outer space sciences and the sea sciences are analytically separable, but practically interlinked. It might be observed in the context of space technology and satellite technics, a new system of management and government, as well as a new system of law and policy. Nowadays, the outer space infrastructure (the use of artificial Earth satellites for Direct Television Broadcasting, communications, remote sensing, navigation, military missiles) affects infrastructure of our Planet, including maritime infrastructure. There is, therefore, the need for a new face of integrated system of science and practice.
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Abstract

A total of sixty five taxa of marine phytoplankton (diatoms, dinoflagellates, silicoflagellates and cyanoprokaryotes) were recorded in the transect from the cold region of the Antarctic (Weddell Sea) up to La Plata Bay, Argentine in the late austral summer (March 1989). Diatoms were the dominant group in a south-north transect from the Seal-Bay (Princess Martha Land, the Antarctic). Most of the phytoplankton species of the cold Antarctic region disappeared around 50°S where there is a steep water temperature gradient. The diatom flora declined in the regions of increasing temperature, i.e. between 60° and 50° S and was replaced by dinoflagellates of the genus Ceratium. Large centric diatom genera Corethron, Rhizosolenia, Chaetoceros and Dactyliosolen represented the most apparent phytoplankton part. The most common of the small centric diatom genera were Thalassiosira, Asteromphalus, Actinocyclus and Coscinodiscus, while several species of Navicula and Nitzschia were the most abundant pennate forms. The presence of a considerable number of freshwater pennate diatoms, characterized as indifferent in the halobion spectrum and mostly periphytic, might be attributed to survival strategies during their development on the floating coastal ice.
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Abstract

In 1920 qualitative and quantitative benthos samples collected in Barents Sea sublittoral in the years 1951-1983 154 species, 77 genera and 30 families of Amphipoda Gammaridea were identified. Species diversity was highest among the Lysianassidae, Oedicerotidae, Ampcliscidae, Calliopiidae and Pleustidae. Ampelisca eschrichti clearly dominated the material. This same species, plus Haploops setosa and Anonyx nugax were both the most frequently occurring and most numerous species. The distribution of amphipods in the Barents Sea sublittoral varies both in diversity and numbers by region, depth, sediments and water temperature. Zoogeographical changes are discussed in the present paper. Altogether 331 species of amphipods have been hitherto collected in the Barents Sea, of which 317 species, 126 genera and 39 families belong to the suborder Gammaridea.
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Abstract

Temperature of superficial water in the Ezcurra Inlet was measured from March 1989 to February 1990, with a use of a mercurial thermometer with accuracy +0.1°C. Temperature was measured usually once a month at selected points. Influence of various factors on temperature of superficial water was preliminarily analysed. Basing on these results, temperature distribution in the mentioned area was determined. Mean yearly temperatures for each station, average space temperatures on measurement days and mean yearly temperatures for the whole area of the Ezcurra Inlet were calculated.
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Abstract

A total of 704 fishes representing 39 species were examined. Twenty five digenean species were recognized. Only one species previously found by the present author in a fiord of this area was absent in the material. Pelagic species were usually not parasitized by digeneans, while demersal fishes were normally found to be infected. Results of the present study are compared to those from fiords. Seven species were found to be widely distributed. Two of them, Macvicaria pennelli and Genolinea bowersi, were associated with an inshore fiord environment and could be used as biological tags indicating the association of hosts with this kind of environment. Three of widely distributed species, Lepidapedon garrardi, Elytrophalloides oatesi and Lecilhaster macrocotyle, were not clearly associated with any environment. Gonocerca phycidis, Neolebouria antarctica and other less widely distributed species, with the exception of Postmonorchis variabilis, were associated with deep part of fiords and/or open sea shelf environment. The level of infection of open sea fish at the South Shetlands was low. Many fish species living at South Georgia were massively infected; the dominant species in this area is E. oatesi, which was rare off the South Shetland Islands. A total of 45 digenean species occurring in the Antarctic fish were listed. Eleven of them were not endemic.
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Abstract

Four water masses were distinguished in the upper water layer between Elephant Island and the South Orkneys. Measurements of temperature, salinity, concentrations of dissolved oxygen and silicates were used for the analysis of the hydrological situation and to recognise the origin of water masses. For additional information, nitrates and chlorophyll concentrations were used. Drake Passage and Bransfield Strait waters occupied the western part of the investigated area, from surface to 150 m depth. Below, the Circumpolar Warm Deep Waters (CWDW) were found. The region east of 53.5°W was occupied by winter Weddell Sea water. Above this, a 45 m thin layer of summer modification of Weddell Sea Surface Water was found between 49°W and the South Orkneys. The highestchlorophyll α concentrations were found in this modified water.
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Abstract

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.
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Abstract

Results of measurements of temperature and salinity of surface waters of the Hornsund (South Spitsbergen) carried out at a coastal point of the Isbjornhamna Bay during the winter expedition 1979/80 of the Polish Academy of Sciences are discussed. Courses of both parameters, their variability, mean values and distributions are analyzed.
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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

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

The Baltic is a unique brakish sea. Its moderate salinity is the result of the fresh river water input and non-periodic inflows of salty, oxygenated waters from the North Sea. However, the balance continually fluctuates. What impact does that have on the sea?
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Abstract

There is a growing interest in new transportation routes that combine benefits of shorter distances, cost-effective transits and routes not troubled by maritime security concerns. The Northwest Passage offers a package of routes through the Canadian maritime zone; it is 9,000 km shorter than the Panama Canal route and 17,000 km shorter than the Cape Horn route. The Northern Sea Route shortens a Hamburg-Yokohama voyage by 4,800 miles, in comparison with the Suez Canal route. The transpolar route, if it materializes with an ice-free Central Arctic Ocean route, would shorten distances even further. Given the increase in regional and international navigation and shipping in the region, it is therefore not surprising that in recent years Arctic States and international bodies focused on the needs of enhanced safety and environmental standards for polar shipping. In addition to the dedicated domestic polar shipping regulation, primarily in Canada and the Russian Federation, the Arctic Council and International Maritime Organization (IMO) have launched important initiatives. The most important is establishing of international rules for ships operating in polar waters – The Polar Code.
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Abstract

Phytoplankton samples were collected at 141 stations in the Norwegian, Greenland, Barents and Baltic seas, in July-August 1992 and July-August 1993. In fifteen of these stations 22 unarmoured dinoflagellate species from the order Gymnodiniales belonging to the genera Amphidinium, Cochlodinium, Gymnodinium, Gyrodinium, Torodinium and Polykrikos have been found. Data on 16 species are given here, including synonyms, size or size variation, localities and environmental factors (temperature and salinity at the surface). 14 species are illustrated.
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Abstract

Chlorophyll a content and the density and species composition of algae were determined in drifting sea ice north of the Elephant Island (between 54-56°W and 60°30'—61°00'S) at the end of October 1986. In yellow-brownish pieces of brash ice the amount of chlorophyll α was on average 203.5 ± 149.9 mg m-3 at the density of algal cells of 255.7+137.8-103 in cm3. In not visibly discoloured ice the respective values were about 80 times lower, and in surface water about 700 times lower. 69 algal taxa were recorded in the samples, almost all of which were diatoms. Nitzschia cylindrus dominated in all the samples. A comparison of species composition in the investigated habitats revealed that the highest species similarities occurred between samples collected in discoloured ice, lower in the uncoloured ice and the lowest ones in water.
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Abstract

The investigations carried out during the 5th Antarctic Expedition of the Polish Academy of Sciences allowed to collect the data concerning specificity of the dynamics of sea-salt nuclei dispersed in the Antarctica region. At the established measuring point measurements at three levels were carried out, basing on which the required profile of the wind characteristics at different heights a.s.l. were obtained.
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Abstract

At the northern border of pack ice the study on chlorophyll a content, density of cells, species composition and domination in samples from the drifting ice floes and from brash ice was carried out. 102 taxa of algae were found in the pack ice. In the study area algal taxa were rather uniformly distributed. In different ice layers the qualitative composition of diatom assemblages was similar and usually the diatom Nitzschia cylindrus was dominant and most frequent. Chlorophyll a content (from 0.12 to 334.5 mg m-3) and the density of cells (from 0.3 to 362 x l0 6 cm) varied strongly in various habitats. Ice floes near the northern pack ice border contained low values of chlorophyll a (mean value 0.50 ±0.28 mg m-3) . However, brash sea ice originating from ice floes, contained 142.4 ±117.5 mg m-3 of chlorophyll α in visibly discoloured and 30.1 ±24.3 mg m~3 of chlorophyll α in not visibly discoloured parts on average. The range of chlorophyll α content and the presence of characteristic species allow to distinguish brash sea ice infiltration assemblage of diatoms.
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Abstract

Based on the results of CTD measurements (in situ) made during r/v „Oceania" cruises in the Norwegian and Greenland Seas in 1986—1988 selected aspects of termohaline structure and water dynamics of chosen regions of the seas were described. Examples of space-time variations of temperature and salinity fields were presented and water masses geostrophic transport on the limits of the Norwegian Sea (upon the Atlantic Ocean and the Barents Sea) was estimated.
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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

In general, Antarctic marine bacteria are small, with biovolumes ranging from 0.139 to 0.204 μm-3 cell-1, but their total biomass in seawater is considerable due to relatively high numbers that approximate to 1020 cells km-3. Bacterial biomass becomes more concentrated closer to land. Our multi-year Antarctic studies demonstrated an average total bacterial biomass of 504 tons in Admirality Bay (24 km3) or 21 tons per 1 km3, versus 6.4 tons per 1 km3 in the open ocean. Strikingly, bacterial biomass reached 330 tons per 1 km3 of seawater at the sea-ice edge, as sampled in Goulden Cove in Admiralty Bay. Bacterial biomass in Admirality Bay, which we believe can be enriched by halotolerant and thermotolerant fresh water bacteria from glacial streams, is equal to or even exceeds that of the standing stock of krill (100-630 tons per bay) or other major living components, including phytoplankton (657 tons), flagellates (591 tons), and ciliates (412 tons). However, the bacterial biomass is exceeded by several orders of magnitude by non-living organic matter, which constitutes the basic bacterial carbon source. Factors regulating high bacterial abundance in the vicinity of land are discussed.
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Abstract

In the years 1987-1989, within the frames of the international program "Greenland Sea Project", the Institute of Oceanology of Polish Academy of Sciences carried out the oceanographic investigations in the energoactive zones of the Northern Atlantic. The paper presents some results of these investigations, characterizing interannual variability of aero- and hydrophysical fields and the causal connections between hydrological and hydrobiological anomalies. Main results of these investigations indicate that the summer season of 1988 was an anomaly in the region of confluence of Barents and Norwegian Seas. This result is irrefutably confirmed by biological data concerning species, and hydrophysical data, such as light attenuation coefficient, fluorescence, spatial distributions of water temperature, salinity, density and current velocity, as well as mass and heat fluxes. It arises from these information that the southern border of the confluence zone was normally the heat „source", while in 1988 it was the heat „sink". The results obtained indicate two reasons responsible for such a situation. The first is the anticyclonic eddy structure of cold Barents Sea waters, penetrating the confluence zone. The second reason seems to be a mechanism blocking the transport of Atlantic water masses through the transect between Faeroe and Shetland Islands.
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