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Number of results: 22
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Abstract

The Bulletin of the Polish Academy of Sciences: Technical Sciences (Bull.Pol. Ac.: Tech.) is published bimonthly by the Division IV Engineering Sciences of the Polish Academy of Sciences, since the beginning of the existence of the PAS in 1952. The journal is peer‐reviewed and is published both in printed and electronic form. It is established for the publication of original high quality papers from multidisciplinary Engineering sciences with the following topics preferred: Artificial and Computational Intelligence, Biomedical Engineering and Biotechnology, Civil Engineering, Control, Informatics and Robotics, Electronics, Telecommunication and Optoelectronics, Mechanical and Aeronautical Engineering, Thermodynamics, Material Science and Nanotechnology, Power Systems and Power Electronics. Journal Metrics: JCR Impact Factor 2018: 1.361, 5 Year Impact Factor: 1.323, SCImago Journal Rank (SJR) 2017: 0.319, Source Normalized Impact per Paper (SNIP) 2017: 1.005, CiteScore 2017: 1.27, The Polish Ministry of Science and Higher Education 2017: 25 points. Abbreviations/Acronym: Journal citation: Bull. Pol. Ac.: Tech., ISO: Bull. Pol. Acad. Sci.-Tech. Sci., JCR Abbrev: B POL ACAD SCI-TECH Acronym in the Editorial System: BPASTS.
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Abstract

The Bulletin of the Polish Academy of Sciences: Technical Sciences (Bull.Pol. Ac.: Tech.) is published bimonthly by the Division IV Engineering Sciences of the Polish Academy of Sciences, since the beginning of the existence of the PAS in 1952. The journal is peer‐reviewed and is published both in printed and electronic form. It is established for the publication of original high quality papers from multidisciplinary Engineering sciences with the following topics preferred: Artificial and Computational Intelligence, Biomedical Engineering and Biotechnology, Civil Engineering, Control, Informatics and Robotics, Electronics, Telecommunication and Optoelectronics, Mechanical and Aeronautical Engineering, Thermodynamics, Material Science and Nanotechnology, Power Systems and Power Electronics. Journal Metrics: JCR Impact Factor 2018: 1.361, 5 Year Impact Factor: 1.323, SCImago Journal Rank (SJR) 2017: 0.319, Source Normalized Impact per Paper (SNIP) 2017: 1.005, CiteScore 2017: 1.27, The Polish Ministry of Science and Higher Education 2017: 25 points. Abbreviations/Acronym: Journal citation: Bull. Pol. Ac.: Tech., ISO: Bull. Pol. Acad. Sci.-Tech. Sci., JCR Abbrev: B POL ACAD SCI-TECH Acronym in the Editorial System: BPASTS.
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Abstract

Na pokładzie „Oceanii” praca trwa 24 godziny na dobę. Ale jest to czas, który każdy, komu było dane go przeżyć, pamięta długo. A może nawet zawsze.
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Abstract

The eight most abundant species (mean density >20 ind. m −2 ), which occurred at high frequencies (mean >30%) were selected from grab samples in the three Svalbard fjords: Hornsund, van Mijenfjord, and Kongsfjord, in the summer seasons between 1997 and 2007. Six polychaete and two bivalve species comprised more than 47% of the individuals and the biomass in all the samples examined. Four species are cosmopolitan, while the others are widely distributed Arctic−boreal species, and none has Arctic origin. Their density, frequency of occurrence, and biology are very similar across the wide geographical range from boreal to Arctic conditions. As the diversity of benthic fauna in the fjords studied increases (from 172 to 238 species), the dominance of the eight species in the soft bottom community diminishes from 76% to 47%. In times of hydrological regime shift, i.e. , the warming of the European Arctic, it is unlikely that the abundancy of these species in the soft bottom fjordic ecosystems will change. The most common soft bottom species are not good indicators of environmental change in the Arctic, and rare, specialized species are better option for indicative purposes.
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Abstract

Thirty-two species of echinoderms from epibenthic sledges, dredges, scuba diving, and other samples (in total: 467 samples and c. 20 000 specimens) from fjords and coastal waters off Spitsbergen were analysed between 1996 and 2014. The most numerous group of echinoderms in the coastal waters off Spitsbergen is brittle stars (78% of the total individuals). The echinoderms do not form any clear assemblages according to depth or distance from glacial sedimentation and substrate. Some species prefer hard bottom (Strongylocentrotus droebachiensis) or water free from glacial suspensions (Ophiopholis aculeata). In contrast to the species listed above, we also found opportunistic species such as the starfish Urasterias lincki and the brittle star Ophiocten sericeum. These two species are distributed quite uniformly, regardless of the environmental factors. The majority of the species prefer a soft bottom below 200 m.
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Abstract

Hornsund and Kongsfjorden are two similar-sized Arctic fjords on the West coast of Spitsbergen. They are influenced by cold coastal Arctic water (Hornsund) and warmer Atlantic water (Kongsfjorden). Environmental conditions affect the timing, quantity, spatial distribution (horizontal and vertical) of spring and summer blooms of protists as well as the taxonomic composition of those assemblages. Here, we compile published data and unpublished own measurement from the past two decades to compare the environmental factors and primary production in two fjord systems. Kongsfjorden is characterized by a deeper euphotic zone, higher biomass and greater proportion of autotrophic species. Hornsund seems to obtain more nutrients due to the extensive seabird colonies and exhibits higher turbidity compared to Kongsfjorden. The annual primary production in the analysed fjords ranges from 48 g C m-2 y-1 in Kongsfjorden to 216 g C m-2 y-1 in Hornsund, with a dominant component of microplankton (90%) followed by macrophytes and microphytobenthos.
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Abstract

10 species of decapod crustaceans were found in Hornsund fiord and adjacent waters of South Spitsbergen. Habitat preferences are given for the species observed as well as distribution maps. Length — weight relationship, length frequency distribution and estimation of life cycles is given for most common species.
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Abstract

Managing human consumption has a major impact on the functioning of societies, and – even more importantly – on the condition of our planet. What does the future hold?
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Abstract

We talk to Prof. Jan Marcin Węsławski from the PAS Institute of Oceanology in Sopot about how scientists work with members of the public and the benefits it brings.
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Abstract

During marine ecological surveys conducted by Polish expeditions in South Spitsbergen area 14 fish species were collected. The length frequency, the diet and some other ecological informations are presented for the most common species.
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Abstract

The comparison of the years 1981/82 and 1984/85 on the background of long term climatic observations on Svalbard suggest that two seasons compared belong to extremely different ones with regard to the sea ice, air temperature and biological phenomena. Despite meteorological and hydrological differences, the phytoplankton bloom and breeding period of major crustaceans were placed in the same time of the year. Differences were noted in the structure of zooplankton community, abundance of sea birds and mammals.
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Abstract

Archaeological investigations were carried out on Sörkappland, the results together with literature data permitted to draw the past distribution of walruses at South Spitsbergen. Recent observations of walruses and marine biological survey indicate good perspectives for the recolonisation of investigated area by walrus population from East Svalbard region.
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Abstract

Life cycles,number of eggs per female,minimal adult female length and reproductive costs are presented for 18 species of Amphipoda from the West Spitsbergen area, 77 –79 °N. Fifteen species incubated eggs during the polar night and released their offspring in early April. Three species incubated eggs from late spring till late summer. The appearance of the youngest juveniles, indicating the hatching period, is presented for 63 species. Most of the species studied were K strategists, with large eggs of over 1 mm diameter; only one species (Hyperoche medusarum ) was r – strategist.
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Abstract

The “Oceania” never sleeps. Her crew work 24 hours per day, and after they disembark they will remember their time aboard for years to come – perhaps forever.
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Abstract

Hornsund, an Arctic fjord in the west coast of Spitsbergen (Svalbard), was selected as All Taxa Biodiversity Inventory (ATBI) site under EU 5th Framework Concerted Action BIOMARE (2000–2002), especially due to its pristine, undisturbed natural character. On the base of large material (89 stations located throughout the fjord and 129 Van Veen grab samples) collected during cruises of RV Oceania in July in 2002, 2003, 2005 and 2007 and literature search a comprehensive list of species recorded within Hornsund area, on the soft bottom with depth range of 30–250 m is provided. Over 220 species were identified including 93 species of Polychaeta, 62 species of Mollusca and 58 species of Crustacea. Species list is supported by information on the zoogeographical status, body length and biological traits of dominant species. Need for further research on Hornsund soft bottom fauna with more sampling effort is highlighted.
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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

The food and foraging strategy of fifteen species of seabirds and sea mammals from two high Arctic fjords were analysed. One of the fjords, Kongsfjord, is strongly influenced by warm waters from the Atlantic , while Hornsund is of a more Arctic character. Prey species in the Atlantic waters were more diverse (82 species and 16 functional groups) compared to those of Arctic waters (67 prey species and 14 functional groups). The consumption of top predators from Hornsund in the peak season of July was estimated at 2.86*106 MJ, while that in Kongsfjord was 1.35*106 MJ. For the analysed function of the ecosystem (the transfer of energy to the top trophic levels) the specific character of prey species is of key importance and not the diversity, abundance or biomass per se. Lower species diversity and biomass in Arctic waters is compensated for by the occurrence of larger individuals of these species, which permits top predators to prey directly on lower trophic levels.
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Abstract

Soft bottom fauna have been sampled along the Spitsbergen fjord depression entering shelf, slope and Greenland Sea Ocean Basin at 200, 300, 500, 1500, 2000 and 3000 m depths. From 19 samples covering 1.9 m2, 4295 individuals of 194 macrofauna species have been sorted. Density decreased markedly from over 6000 ind/m2 in shelf stations to some 600 ind/m2 below 1500 m depth. Only two taxa (Chaetozone group and Lumbrineris sp. A) occurred in more than 75% of samples, 55 taxa (28% of the total) were represented by single specimens only. The highest number of species per sample (65 taxa in 0.1 m2) was noted at 525 depth. There were 14 eurybathic species and the same number of taxa were found exclusively below 2000 m depth, while 117 species were found only shallower than 300 m depth.
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Abstract

Suspended matter, phytoplankton and light attenuation were investigated in various North East Greenland, Svalbard and Siberian river mouths in 1992-1994. The amount of mineral suspensions well correlated with freshwater discharge in the case of tidal glacier bays, while such correlation in Siberian rivers and pack ice meltwater was not found. Freshwater phytoplankton species were found in Siberian estuaries only and in two other ecosystems marine and ice phytoplankton species prevailed. The light attenuation connected with freshwater discharge seems to be a key factor limiting primary production in coastal Actic waters in the summer. The amount of glacial suspensions well correlated with the salinity drop in the case of Svalbard, while Siberian river estuaries produced very turbid waters with the suspension loads not correlated to freshwater or depth.
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