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Number of results: 1087
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Abstract

The embryology of three polar flowering plants of the family Caryophyllaceae was studied using the methods and techniques of the light, normal and fluorescence microscopes, and the electron microscopes, scanning and transmission. The analyzed species were Colobanthus quitensis of West Antarctic (King George Island, South Shetlands Islands) as well as Cerastium alpinum and Silene involucrata of the Arctic (Spitsbergen, Svalbard). In all evaluated species, flowering responses were adapted to the short Arctic and Australian summer, and adaptations to autogamy and anemogamy were also observed. The microsporangia of the analyzed plants produced small numbers of microspore mother cells that were differentiated into a dozen or dozens of trinucleate pollen grains. The majority of mature pollen grains remained inside microsporangia and germinated in the thecae. The monosporous Polygonum type (the most common type in angiosperms) of embryo sac development was observed in the studied species. The egg apparatus had an egg cell and two synergids with typical polarization. A well-developed filiform apparatus was differentiated in the micropylar end of the synergids. In mature diaspores of the analyzed plants of the family Caryophyllaceae, a large and peripherally located embryo was, in most part, adjacent to perisperm cells filled with reserve substances, whereas the radicle was surrounded by micropylar endosperm composed of a single layer of cells with thick, intensely stained cytoplasm, organelles and reserve substances. The testae of the analyzed plants were characterized by species-specific primary and secondary sculpture, and they contained large amounts of osmophilic material with varied density. Seeds of C. quitensis, C. alpinum and S. involucrata are very small, light and compact shaped.
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Authors and Affiliations

Wioleta Kellmann-Sopyła
Irena Giełwanowska
Justyna Koc
Ryszard J. Górecki
Marcin Domaciuk
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Abstract

It is generally accepted that ice cores archive amount-weighted water stable isotope signals. In order to achieve an improved understanding of the nature of water stable isotope signals stored in ice cores annual δ18O and δ2H averages (i.e. amount-weighted) were calculated for two Antarctic meteorological stations, Vernadsky and Hal-ley Bay, using monthly precipitation amount and monthly net accumulation as weights, respectively. These were then compared with the annual mean δ18O δ2H and records of the nearest available ice cores. In addition, at the stations, both arithmetic means (i.e. time-weighted) and amount-weighted (precipitation amount and net accumulation used as weights) annual air temperature averages were calculated and then compared to amount weighted annual mean δ18O and δ2H using correlation- and regression analyses. The main hypothesis was that amount weighted annual mean water isotope and temperature records from the stations would be able to replicate the annual water isotope signal stored in ice cores to a higher degree. Results showed that (i) amount weighting is incapable of ameliorating the signal replication between the stations and the ice cores, while arithmetic means gave the stronger linear relationships; (ii) post depositional processes may have a more determining effect on the isotopic composition of the firn than expected; and (iii) mean annual air temperature provided the closest match to ice core derived annual water isotope records. This latter conveys a similar message to that of recent findings, in as much as ambient temperature, via equilibrium isotope fractionation, is imprinted into the uppermost snow layer by vapor exchange even between precipitation events. Together, these observations imply that ice core stable water isotope records can be a more continuous archive of near-surface temperature changes than hitherto believed.
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Authors and Affiliations

István Gábor Hatvani
Zoltán Kern
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Abstract

The results of several years of studies concerning the role of penguin rookeries in the functioning of the land ecosystems in the maritime Antarctic are summarized. The origins of phosphatic ornithogenic soil in the areas of currently active penguin rookeries arc presented. In the maritime Antarctic occurs relatively fast microbiological decomposition and mineralization of large amounts of excrements carried into coastal area by penguins during breeding period. Chemically aggressive water solutions of guano react with underlaying rocks. This process brings about the occurrence of wide zones of phosphatization. These processes cause the appearance of the series of phosphate minerals whose composition and properties depend on the changing physical and chemical conditions of the soil environment. It has been discovered that in the rookeries for various reasons abandoned by penguins phosphates are still present in large amounts and, gradually changed and washed out, have been for hundreds, or even thousands years a source of nutrients for plants growing in poor Antarctic land ecosystems. These soils came to be called the relic ornithogenic soils of the maritime Antarctic. The stages of plant colonization in the abandoned penguin rookeries were traced. The differences in the fate of the organic matter carried out from the sea to the coastal area by sea-birds in various climatic zones were discussed.

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Authors and Affiliations

Andrzej Myrcha
Andrzej Tatur
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Abstract

Soils of Russian European North were investigated in terms of stability and quality of organic matter as well as in terms of soils organic matter elemental composi-tion. Therefore, soil humic acids (HAs), extracted from soils of different natural zones of Russian North-East were studied to characterize the degree of soil organic matter stabilization along a zonal gradient. HAs were extracted from soil of different zonal environments of the Komi Republic: south, middle and north taiga as well as south tundra. Data on elemental composition of humic acids and fulvic acids (FAs) extracted from different soil types were obtained to assess humus formation mechanisms in the soils of taiga and tundra of the European North-East of Russia. The specificity of HAs elemental composition are discussed in relation to environmental conditions. The higher moisture degree of taiga soils results in the higher H/C ratio in humic substances. This reflects the reduced microbiologic activity in Albeluvisols sods and subsequent conser-vation of carbohydrate and amino acid fragments in HAs. HAs of tundra soils, shows the H/C values decreasing within the depth of the soils, which reflects increasing of aromatic compounds in HA structure of mineral soil horizons. FAs were more oxidized and contains less carbon while compared with the HAs. Humic acids, extracted from soil of different polar and boreal environments differ in terms of elemental composition winch reflects the climatic and hydrological regimes of humification.
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Authors and Affiliations

Evgeny Abakumov
Evgeny Lodygin
Vasily Beznosikov
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Abstract

Eighteen sediment samples from a 36 cm long sediment core retrieved from a proglacial lake (namely P 11) situated in the Schirmacher Oasis, East Antarctica, were analysed for the study of quartz grain morphology and microtexture, along with sand percentage, to reconstruct the paleoenvironmental changes in the lake during the Holocene. The age of the core ranges from 3.3 ka BP to 13.9 ka BP. The quartz grain morphology and microtexture reveal significant evidences of glacial transport along with some eolian and aqueous activities. On the basis of predominance of these signatures and the zonation from CONISS Cluster Analysis on the percentages of characteristic grain morphology and microtextures, the entire core has been subdivided into three major zones. From the paleoenvironmental perspective, it can be concluded that there is an onset of interglacial period at the advent of Holocene (12.3 ka BP), which reigned until 5.3 ka BP and thereafter, again a glacial environment prevailed until 3.3 ka BP with some variations in-between. The results indicate probable alternative colder and less colder phases in the study area, which are also well supported by the respective sand percentages in the sediments. © 2017 Polish Academy of Sciences 2017.
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Authors and Affiliations

Abhijit Mazumder
Pawan GOVIL
Ratan Kar
Narath Meethal Gayathri
RAGHURAM
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Abstract

This paper presents a unique case study and methodology for measurements of the bedload transport in the two, newly created troughs at the forefield of the Baranowski Glacier: Fosa and Siodło creeks. The weather conditions and the granulometric analysis are presented and discussed briefly. Rating curves for the Fosa and Siodło creeks are presented for the first time for this region. Changes of the bedload transport as well as water discharge and water velocity at both creeks are investigated. The hysteresis for the relationships between rate of bedload transport and water discharges were identified showing that for both creeks for the higher water levels a figure of eight loop may be easily recognized. Moreover, a new method for the calculation of bedload transport rate, based on the weighted arithmetic mean instead of the arithmetic mean, is proposed.
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Authors and Affiliations

Joanna Sziło
Robert J. Bialik
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Abstract

A two-year-long data set of air temperature from four different altitudes above Petuniabukta, central Spitsbergen, was analysed in order to assess the near-surface temperature lapse rates and the relative frequency of air temperature inversion occurrence. From August 2013 to July 2015, air temperatures at adjacent altitudes in Petuniabukta were strongly correlated. The near-surface lapse rates in all three layers differed significantly both from the average lapse rate in the international standard atmosphere (0.65°C 100 m-1) and the lapse rate calculated by linear regression. A pronounced annual cycle was detected in the lowermost air layer (from 23 to 136 m a.s.l.) with a variable near-surface lapse rate in the winter months, while an annual cycle was not apparent in the air layers above 136 m a.s.l. The lowermost layer was also characterized by a notable daily cycle in near-surface lapse rate in spring and autumn. Air temperature inversions occurred in up to 80% of the study period in the air layer below 136 m a.s.l., with the relative frequency being much lower in the other two air layers. The air temperature inversions lasted as long as 139 hours. A case study revealed that one of the strongest air temperature inversions was connected to an area of lower pressure gradients at the 850-hPa pressure level.
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Authors and Affiliations

Klára Ambrožová
Kamil Láska
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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

Przedstawiono wykaz nowych nazw geograficznych wprowadzonych na obszarze Wyspy Seymour (Marambio), Półwysep Antarktyczny (fig. 1, pl. 1—2) w czasie prac terenowych argentyńsko-polskiej grupy geologicznej w sezonie 1993-1994.

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Authors and Affiliations

Andrzej Gaździcki
Andrzej Tatur
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Abstract

New information about presence and features of some Lecanora species as well as their ecology and distribution in Antarctica are provided. Lecanora dispersa (Pers.) Sommerf. is confirmed to occur in the Antarctic region; L. sverdrupiana Řvst. is recorded for the first time from maritime Antarctica; L. torrida Vain. is reported as new for that Antarctic area and for the southern hemisphere. An attempt to summarize the present state of knowledge for the genus Lecanora in the Antarctic region is made. Several species, which require more in depth studies, are briefly discussed and an up-to-date list of species occurring in Antarctica is included.

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Authors and Affiliations

Lucyna Śliwa
Maria Olech
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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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Authors and Affiliations

Jan Marcin Węsławski
ORCID: ORCID
Joanna Legeżyńska
ORCID: ORCID
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Abstract

The population structures of Calanus finmarchicus, C.glacialis and C.hyperboreus were investigated in the recurrent polynya of the North Waters (NOW) in Baffin Bay during April –July 1998. Species were determined from samples collected by plankton nets of 300 ľm and 200 ľm mesh size. The highest concentration of all three species was found at the centre of study the area. C.hyperboreus was the most abundant species (44.54 ind.m –3).C.glacialis was recorded up to 27.14 ind.m –3, C.finmarchicus up to 5.63 ind.m –3 .C.finmarchicus was reproducing in the northern end of Baffin Bay.The life cycle for C.glacialis was estimated at 2 years,and that of C.hyperboreus to last at least 4 years.

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Authors and Affiliations

Anna Prokopowicz
Louis Fortier
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Abstract

The multidisciplinary journal Polish Polar Research is bibliometrically analysed as a medium of international scientific communication in light of current citation data from SCI Ex 1996 -2002. Despite its world-wide distribution and distinctive visibility in the polar society, the journal 's two-years impact factor is invariably not very high (below 0.35) because the cited papers are mostly from the 1980s. The increasing participation of foreign (co)authors in the Polish quarterly, paired with the slowly growing number of citing articles in SCI Ex are already promising steps to the immediate information transfer and subsequently improved brief-term journal impact. Citation links with polar investigators from Germany,and also from Great Britain, Spain and the USA are clearly manifested, especially in fields of marine Antarctic ecology and biology. Even if Polish Polar Research may successfully compete with several low-rated journals from different countries indexed in SCI Ex in related categories, its continuing internationalization is urgently required.

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Authors and Affiliations

Grzegorz Racki
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Abstract

Notothenia coriiceps, N.rossii and Lepidonotothen nudifrons were sampled from Admiralty Bay from March to November 1997 and from January to February 1999. The ratio of N.coriiceps to N.rossii individuals in catches regularly increased during 22 years from 0.4 in 1977 to 9.5 in 1999. Oving to its reproductive strategy and avoidance of shallow waters N.rossii may be more vulnerable to overfishing. The condition factor was the most stable (CV 6 -10%), variations in the of hepatosomatic index and index of stomach fullness were intermediate (21 -38%and 40 -43%,respectively), and the gonadosomatic index was the most variable (65 -100%). Lack of seasonality in two somatic indices (condition factor and index of stomach fullness) in N.coriiceps adults is a direct effect of high food availability and unlimited food detection all year round. In contrast, the seasonality of a reproductive index (gonadosomatic index) of these fish is a response to the highly seasonal trophic conditions for pelagic larvae.

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Authors and Affiliations

Ewa Kamler
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Abstract

Bryozoans were collected in Kongsfjorden (79°N and 12°E) in the summer seasons of 1997, 1998, and 1999. In the total of 44 grab, dredge, and SCUBA diving samples 143 taxa were determined: 123 species, 17 to the generic and 3 to the family level. In the investigated material were 24% Arctic species and 66% boreal-Arctic species. This suggests a rather Arctic nature of the fjord. A few boreal species indicate the influence of warm water masses (West Spitsbergen Current). The majority of species (76%) have an encrusting life form. There were 5 species with a frequency of occurrence higher than 20%. These are Electra crustulenta var. arctica (31.82%); Cylindroporella tubulosa (27.27%); Tegella arctica (22.73%); Tegella armifera (20.45%); and Hippothoa divaricata var. arctica (20.45%). Among all identified species 23 were recorded for the first time in the area of Svalbard archipelago. Most (79%) of newly noted species have Arctic distributions. The lower sampling effort of previous researchers most likely accounts for the present enrichment of the list of Bryozoa of Kongsfjorden.

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Authors and Affiliations

Piotr Kukliński
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Abstract

This article presents an inventory of the marine benthic harpacticoids (Crustacea, Copepoda) from the area of Svalbard (including Bear Island). Information concetning the occurrence of 90 taxa in the shallow littoral zone of Svalbard is presented based on own samples as well as published and unpublished sources. Two species and 7 genera are reported for the first time from the investigated area.

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Authors and Affiliations

Lech Kotwicki
ORCID: ORCID
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Abstract

The results of a statistical analysis of the influence of the Hansbreen surface ablation relative to selectedmeteorological parameters (air temperature andsunshine duration) are presentedhere. Over the period1989 –2001 the lowest summer balance on the surface ablation of Hansbreen was recorded in 1994 (–0.56 m water equivalent). Concurrently, both the air temperature (mean seasonal ~2.3 °C) and the sunshine duration (seasonal sum ~278.9 h)were at their lowest. Owing to the relatively high sunshine duration (676.5 h),the highest values were in 1998 (–1.71 m w.e.); likewise,in 2001 (–1.84 m w.e.) when a high air temperature (mean of 3.6 °C) occurred. The statistical models erected on the basis of these data allow us to estimate fairly reliably the seasonal ablation of Hansbreen. The basis of these is the reasonably reliable relationship determinable between the seasonal sum of PDD (positive degree days) and the ablation intensity changes in respect of altitude above sea level. Sunshine duration is regarded here as being of very little significance in terms of increasing the accuracy of the models. The errors inherent in this models varies from 28% to as little as 7%. Shown models may eventually find application as a method of calculating the amount of water resulting from the decay of tidewater glaciers.

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Authors and Affiliations

Joanna Szafraniec
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Abstract

A few specimens of a macroporid bryozoan were collected, from the Eocene La Meseta Formation from Seymour (Marambio) Island, Antarctic Peninsula. Based on the morphology of the studied specimens Macropora antarctica sp.n. has been erected. This is the stratigraphically oldest species of the genus which exhibits a number of similarities with the Tertiary fossils and some Recent macroporids reported from the Southern Hemisphere i.e., Australia, New Zealand and South America.

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Authors and Affiliations

Urszula Hara
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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

Eocene penguin remains from Seymour Island (Antarctica) are so far the oldest−known record of extinct Sphenisciformes. Rich Argentineand Polish collections of penguin bones from the La Meseta Formation are taxonomically revised on tarsometatarsal morphology. Two genera and four species are erected: Mesetaornis polarisgen. et sp. n., Marambiornis exilisgen. et sp. n., Delphinornis arctowskiisp. n. and D. gracilissp. n. Moreover, the diagnoses of already described species: Anthropornis nordenskjoeldi, A. grandis, Palaeeudyptes klekowskii, P. gunnari, Archaeospheniscus wimani and Delphinornis larseniare revised as well. Gradual cooling of climate, changes of environment andtrophic relationships, that lasted several millions years, were most probably responsible forthe intense speciation and taxonomic diversification of the Middle–Late Eocene La Meseta penguins.

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Authors and Affiliations

Andrzej Myrcha
Piotr Jadwiszczak
Claudia P. Tambussi
Jorge I. Noriega
Andrzej Gaździcki
Andrzej Tatur
Rodolfo A. del Valle
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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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Authors and Affiliations

Ryszard Ligowski
Elżbieta Kopczyńska

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