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Abstrakt

The period from arrival of the Wilson's petrel to its breeding grounds to the onset of breeding covered 33 days (November 5 — December 8). The egg-laying period averaged 56 days; the frequency distribution of egg laying in different colonies was close to normal. Incubation took 44 days, on the average, and chicks stayed in nests 59 days. The weight of chicks at hatching was 7.5 g, and the maximum weight was 80 g, that is, 205"o of adult weight. Growth rate of chicks depended on weather conditions, especially on the amount of snowfall, blocking the access to the neast. This caused many-day starvation of chicks and their weight could drop by 46"',.. The diet of chicks and adults consisted of the krill in 96% mostly of Euphausia superba High nesting losses were caused by rainfall and snowfall. Of 129 nesting attempts, 61.2% failed in the stage of eggs and 27.9% in the stage of chicks. Mortality was related to the age and weight of chicks. It has been found that the prolonged egg-laying period, rapid growth rate of chicks in their first days, and their high weight represent adaptations to the climate of Antarctica.
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Abstrakt

In the region of the Admiralty Bay 12 nesting bird species were encountered of a total abundance of 40890 pairs and biomass amounting to about 395000 kg Three penguin species constituted 91.7% in abundance, their biomass constituting 98.7% of the whole community. Densities of abundance and biomass of adult birds in relation to the living area of penguins (i.e. 775 km2) ranged from 32.3 to 121.4 indiv. km-2 and from 115.1 to 4730 kg k m-2.
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Abstrakt

In the investigated area krill occured in low abundance. It was recorded mainly above the shelf and above the continental slope close to the Palmer Archipelago and near the northern shores of Elephant Island. In the central part of the Bransfield Strait E. superba was caught in especially small quantities. In general krill of small size occurred, the size decreasing from the west to the east. Mature krill was dominan in the western part of the investigated area, whereas juveniles in the eastern part. Gravid females were caught very rarely.
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Abstrakt

Seasonal changes in the Antarctic krill (Euphausia superba Dana) autoproteolytic activity were followed throughout the year. Using the kinetic formula for the first order reaction, the initial reaction rate (y0), the rate after 5 minutes (y5) and the average reaction rate (yx) after 0, 5, 10, 15 and 20 min of incubation of mixed homogenate at 40° + 0.2°C were determined in each sample. Changes in the krill autoproteolytic activity over the year were found to follow a sinusoid with a maximum during the austral summer (January) and a minimum during the austral winter (July-August). The maximum initial reaction rate was about ten times the minimum initial rate, which is an evidence of a considerable seasonal variation in the krill autoproteolytic activity associated presumably with the krill feeding intensity.
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Słowa kluczowe Antarctic krill fluoride content

Abstrakt

An attempt at assessing the correlation between the content of fluoride in the Antarctic krill from various fishery and its.biological condition was carried out Fluoride was determined with the Dolan method, which was modified by the present authors. No statistically significant correlation was found between the degree of sexual maturity and fluoride content. There was no decisive statistical relation between the body weight and body length of individuals and the content of fluoride in the Antarctic krill.
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Abstrakt

Carotenoid composition of both penguin faeces and the lichen Caloplaca regalis has been analyzed by thin layer chromatography. Carotenoids in both samples are almost identical to those found in the krill, the main food of the penguins, including β-carotene, which is not found in other Theloschistaceae species.
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Abstrakt

Carotenoids in six species of the lichens from Antarctica (Xanthoria eleguns, Caloplaca regalis, Usnea antarctica, U. fasciata, Himantormia lugubris and Ramalina terebrata) have been investigated by means of column and thin — layer chromatography. The following carotenoids were found: β-carotene, α- and β-cryptoxanthin, canthaxanthin. lycophyll, lycoxanthin, lutein, lutein epoxide, zeaxanthin, antheroxanthin, adonixanthin, diatoxanthin, rhodoxanthin, rhodoxanthm derivative, α-doradexanthin, astaxanthin, astaxanthin ester, mutatochrome, mutatoxanthin and cryptoflavin. Most frequently occurred β-carotene, β-cryptoxanthin, lutein epoxide, zeaxanthin and mutatoxanthin. The total carotenoid content ranged from 10.242 (Ramalina terebrata) to 18.700 mg/g dry weight (Himantormia lugubris) in October and from 4.765 (Ramalina terebrata) to 12.462 mg/g dry weight (Caloplaca regalis) in February.
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Słowa kluczowe Antarctica biogeography

Abstrakt

The method of construction and division of dendrites proposed by Florek et al. (1951) was used for defining of the Antarctic biojjeographic areas. The affinity matrices of Knox and Lowry (1977) resulting from the analysis of the distribution of Antarctic Polychaeta and Amphipoda were taken as a basis for dendrite construction The results of the present analysis are compared with the conclusions of these authors and similarities and differences are discussed on the background of the hitherto published biogeographic divisions of Antarctica.
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Abstrakt

Grimmia andreaeopsis C. Muell., a species described from sterile material from the Chukotka Peninsula, is redescribed and illustrated The species is actually a member of the genus Schistidium. It can be distinguished from its closest relatives, viz. species of S. strictum complex, by the possession of a unique combination of characters: (1) inky black coloration of gametophytes; (2) strongly and asymmetrically keeled, rapidly wide-spreading to squarrose when moist, leaves; (3) cells entirely smooth, very incrassate and strongly nodulose nearly to the base of the lamina: (4) a costa totally smooth or only occasionally slightly roughened on the back below the apex, but never scabrous with conical papillae; (5) leaf margins always entire; (6) peristome teeth bluntly acuminate. Unlike most rupestral species of Schistidium it grows in wet arctic fens. S. holmenianum Steere & Brassard, a species known to be widely distributed in the Nearctic, and Racomitrium depressum Lesq. var. nigricans Kindb., a variety described from Labrador and Hudson Bay. are synonymous with S. andreaeopsis (C. Muell.) Laz. A comparison of S andreaeopsis with the Andean-Subantarctic S. anqustifolium (Mitt.) Herz is made and these species are considered to be closely related, but not conspecific, bipolar counterparts. Also, a comparison with the South Georgian S. urnulaceum (C. Muell.) Bell and the Holarctic species of S. strictum complex, which are characterized by having similar leaf cell patterns, is made. S. andreaeopsis has a circumpolar distribution, mainly within the High Arctic. In addition to the Nearctic, the species is known to occur in Svalbard, North Land, Taymyr Peninsula, Yakutia, Wrangel Island, and on the Chukotka Peninsula.
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Słowa kluczowe Arctic Spitsbergen phytal benthos

Abstrakt

The paper describes the communities of laminarians and their macrofauna at the western coasts of Spitsbergen. The following aspects are considered: specific composition of fauna, spatial distribution of animals within the algae, trophic structure of fauna associated with the laminarians. Some zoogeographic remarks are included.
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Słowa kluczowe Antarctic krill chitin metals

Abstrakt

Concentration of Zn, Cu, Cd, Pb and Co have been determined in Antarctic water (South Shetland Islands) and in krill exoskeletons with the help of atomic absorption spectrophotometry. Concentrations of these metals both in sea-water and in krill exoskeleton are in order Zn > Cu > Cd > Ni > Pb > Co. Comparing concentrations of these metals in sea-water to their concentrations in krill exoskeleton, the factors have been calculated giving a list of metals in the order of krill chitin ability, which is Ni > Cu > Zn > Cd > Pb > Co accumulation. The highest accumulation factors for Ni and Cu point out to the special role played by these metals in krill life.
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Abstrakt

The attempt was made to describe the dynamics of water masses in the southern part of the Drake Passage and the Bransfield Strait in the time period from December 1983 to January 1984. The dynamic topography at the surface (referred to 500 dbar surface) allowed to define the eastward flow of water in the Bransfield Strait and to observe, in the same region, the presence of a rather weak counter-current of the Weddell Sea origin. In the Drake Passage, a general north-eastern direction of water flow of the Bellingshausen Sea was found. In the Bransfield Strait, as well as in the Drake Passage, the relative velocities of geostrophic flow were low: 0.22 and 0.06 m s-1 respectively. The analysis of Rossby and eddy numbers and Rossby radius made it possible to regionalize the dynamic phenomena but could not be fully used for their classification.
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Słowa kluczowe Antarctic penguins microclimate

Abstrakt

The microclimate of the nest-sites of Pygoscelis adeliae, P. antarctica and P. papua was studied from December 1979 to January 1981. The temperature of the ground, air temperature at 0.05 m, 0.35 m ad 2 m and wind velocity at 0.35 m and 2 m above the ground were recorded. The wind velocity in the places chosen by penguins for nesting was lower than at the meteorological station by 22% to 60%. It was proved that in winter the mean monthly ground temperature at the nesting places was lower than that at the meterological station by 6 to 8°C due to the much thinner snow cover. Pygoscelid penguins chose for nesting places of specific microclimate and modified the wind velocity, temperature of the ground and, to a leser extent, the air temperature.
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Abstrakt

There were tested microorganisms in differents soils at Admiralty Bay region. The physiological groups of microorganisms were restricted by the kind of organic matter. There were found in ornithogenic soils in higher number the following groups of microorganisms; proteolytic bacteria, uric acid and L-asparagine ammonifying bacteria, chitin degrading bacteria, lecithin degrading bacteria and calcium phosphate dissolving bacteria. The nitrifying bacteria were found in lower horizons of ornithogenic soils in higher number. The nitrogen fixing bacteria were found in mineral soils covered by plant associations, only. The spore-forming bacteria were detected in ornithogenic soils and in soil influenced by man.
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Abstrakt

226 taxa (180 identified to species) of benthic invertebrates are recorded from Admiralty Bay on the basis of the material collected by Polish Antarctic Expeditions. Main groups concerned are Folychaeta, Mollusca, Amphipoda and Echinodermata. For each species the bathymetric range, the frequency, the abundance and the geographical distribution are given.
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Abstrakt

In 1977 and 1980 rich materials of necrophagous invertebrates were collected in the Admiralty Bay of King George Island. The collecting was carried out in 9 stations differing with respect to their habitat conditions. The stations were established at depths ranging from 5 to 90 m. In baited traps placed in the stations 295074 specimens of various animals belonging to almost 100 taxa were caught. It was found that 23 species out of the above mentioned taxa were necrophagous, and 10 further species were suspected of necrophagy. On the basis of their specific composition and domination structure the summer and winter assemblages of necrophagous invertebrates were described and compared with each other. An analysis of spatial and seasonal changes in the structure and abundance of these assemblages was carried out. and the habitat preferences of particular species as well as a list of species displaying permanent or seasonal necrophagy were determinted. Three forms of the competitive community of necrophagous invertebrates were distinguished.
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Abstrakt

By means of the synthetic diagram method (Romaniszyn 1970) populations of benthic Polychaeta at the depth ranging from 15 to 250 m of the Admiralty Bay (South Shetland Islands) were analysed. During the summer season of 1979/80 three replicate subsamples were taken at 18 stations situated along 3 crosssections using the Van Veen grab of a catching area of 0.09 m2 ; 61 benthic taxa of Polychaeta were recorded in these samples. The characteristics of particular assemblages are presented together with their tendency to change as a result of substrate quality, depth and position in the study area. Considerable affinity between the fauna of Polychaeta in the shallowest part of the bay and the composition and structure of polychaete assemblages occurring at Arthur Harbor (Anvers Island), which were described by Richardson and Hedgpeth (1977) was recorded.
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Abstrakt

In the present paper several species of moss-mites (Acari, Oribatida), including a species new for science (Halozetes impeditus sp. nov.) caught in the vicinity of the Polish "H. Arctowski" Station on King George Island (South Shetlands) are discussed.
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Abstrakt

Phytoplankton sampling from 13 stations situated in Admiralty Bay was carried out in March. April, May, October and November 1983. Wet settling volume of seston, its dry weight, number of cells under 1 m2 , and qualitative composition of phytoplankton were determined. It was found that amount of phytoplankton was decreasing in April and increasing again in November after the winter season. The share of benthic and periphyton species in the qualitative composition of phytoplankton was quite significant, whereas their quantitative share was rather small. 163 taxa of algae were identified in the net phytoplankton; among these 107 taxa were reported for the first time from the Admiralty Bay. Most abundantly met throughout the entire study period were: Corethron criophilum and Thalassiothrix antarctica.
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Abstrakt

The paper comprises the review of all 23 known valid species along with synonyms and polytomic keys based on morphological features. Mature specimens of 8 species occur in fishes, 4 in birds, 11 in mammals. Each species settles in a definite section of the digestive tract. The structure of a population is dependent upon the time which has passed since the moment of invasion and the intensity of infestation. Acathocephalans can be found in hosts all the year round, but incomplete seasonality of the occurrence of 2 fish parasites has been recorded. Fish parasites show wide specificity in relation to the hosts mentioned while bird and mammal parasites specificity is narrow. The majority of acanthocephalan species have circumpolar distribution but only 3 have been found inside the polar circle and the other 7 are common in the environs of subcontinental archipelagoes. Acanthocephalans do not yield precedence as far as the diversity of species and infestation intensity are concerned in the Antarctic to other groups of parasite helminths. Their great importance results from their mass occurrence in the vertebrates which are the focus of. man's practical interests — fishes, seals and whales.
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