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1.
This study is part of the Soviet-Norwegian Oceanographic Programme (SNOP) on ice and water dynamics in the region between Svalbard and Frans Josef Land. The effects of the movements of water and ice on the ice regime are discussed. Due to the scarcity of data, numerical hydrodynamica] simulations are used. The tidal ice drift is visualized on satellite images as elliptically shaped traces in the ice fields formed by grounded icebergs. These traces are a result of the joint action of tides, wind and permanent currents. 相似文献
2.
STEPHANIE PFIRMAN JEAN-CLAUDE GASCARD INGO WOLLENBURG PETA MUDIE REA ABELMANN 《Polar research》1989,7(1):59-66
During the summer 1987 expedition of the polar research vessel'Polarstern'in the Eurasian Basin of the Arctic Ocean, sea ice at about 84-86°N and 20-30°E was found to have high concentrations of particulate material. The particle-laden ice occurred in patches which often darkened more than half the ice surface at our northernmost positions. Much of this ice appeared to be within the Siberian Branch of the Transpolar Drift stream, which transports deformed, multi-year ice from the Siberian shelves westward across the Eurasian Basin. Lithogenic sediment, which is the major component of the particulate material, may have been incorporated during ice formation on the shallow Siberian seas. Diatoms collected from the particle-rich ice surfaces support this conclusion, as assemblages were dominated by a marine benthic species similar to that reported from sea ice off the coast of northeast Siberia. Based on drift trajectories of buoys deployed on the ice it appears that much of the particle-laden ice exited the Arctic Ocean through the Fram Strait and joined the East Greenland Current.
Very different sea ice characteristics were found east of the Yermak Plateau and north of Svalbard and Frans Josef Land up to about 83-84°N. Here sea ice was thinner, less deformed, with lower amounts of lithogenic sediment and diatoms. The diatom assemblage was dominated by planktonic freshwater species. Trajectories of buoys deployed on sea ice in this region indicated a tendency for southward transport to the Yermak Plateau or into the Barents Sea. 相似文献
Very different sea ice characteristics were found east of the Yermak Plateau and north of Svalbard and Frans Josef Land up to about 83-84°N. Here sea ice was thinner, less deformed, with lower amounts of lithogenic sediment and diatoms. The diatom assemblage was dominated by planktonic freshwater species. Trajectories of buoys deployed on sea ice in this region indicated a tendency for southward transport to the Yermak Plateau or into the Barents Sea. 相似文献
3.
ERIK W. BORN 《Polar research》1984,2(1):27-45
Observations of walrus in the Svalbard area in the period 1954-1982 indicate an increase since 1970 in the numbers summering in this area. The numbers of walrus observed show annual fluctuations. With the exception of 1973, when at least 300 animals were observed on one occasion at Kvitøya, the observations indicate a summering stock of about 100 animals. In 1982, when most walrus habitats in Svalbard were surveyed, observations of 248-274 animals were recorded. These observations were estimated to represent 82–85 individuals.
During summer, walrus are most frequently observed at Tusenøyane, in Murchisonfjorden and along adjacent coasts, along the northern coast of Nordaustlandet, at Kvitoya, and at Moffen. Apparently, the walrus re-established the use of Moffen as a summer haul-out site about the beginning of the 1970s.
An apparent under-representation of observations of females with dependent calves in Svalbard indicates that the area is mainly used as a summering area by males and that Svalbard is in the process of being repopulated by an extension of a population centred elsewhere. It is suggested that the walrus summering in Svalbard belong to a population with its main distribution in the Frans Josef Land archipelago, but at least some may be derived from a walrus population(s) occurring at Novaja Zemlja and in the Kara Sea. 相似文献
During summer, walrus are most frequently observed at Tusenøyane, in Murchisonfjorden and along adjacent coasts, along the northern coast of Nordaustlandet, at Kvitoya, and at Moffen. Apparently, the walrus re-established the use of Moffen as a summer haul-out site about the beginning of the 1970s.
An apparent under-representation of observations of females with dependent calves in Svalbard indicates that the area is mainly used as a summering area by males and that Svalbard is in the process of being repopulated by an extension of a population centred elsewhere. It is suggested that the walrus summering in Svalbard belong to a population with its main distribution in the Frans Josef Land archipelago, but at least some may be derived from a walrus population(s) occurring at Novaja Zemlja and in the Kara Sea. 相似文献
4.
Breeding biology, nestling growth and development, and biometry of the little auk Alle alle polaris were studied in Franz Josef Land. A total of 103 adult birds were measured, 60 in the field and 43 in the St. Petersburg Museum. The development of 16 chicks was compared with that of Alle a. alle chicks from Spitsbergen. At particular stages of development, both adults and nestlings of A. a. polaris are larger than those of A. a. alle .
In Franz Josef Land the breeding season is more extended and less synchronised than that of Svalbard. The majority of the little auks in the studied colonies in Franz Josef Land nested on steep rocky cliffs, possibly as an adaptation to the severe climatic conditions and heavy mammalian predation in subcolonies located on accessible mountain slopes. Glaucous gulls Larus hyperboreus exerted negligible predatory pressure. This study confirms the existence of morphologically distinguishable populations of the little auk on Franz Josef Land and Svalbard, supported by recent studies of climatic and oceanographic conditions in the two areas that parallel the morphological differentiation. 相似文献
In Franz Josef Land the breeding season is more extended and less synchronised than that of Svalbard. The majority of the little auks in the studied colonies in Franz Josef Land nested on steep rocky cliffs, possibly as an adaptation to the severe climatic conditions and heavy mammalian predation in subcolonies located on accessible mountain slopes. Glaucous gulls Larus hyperboreus exerted negligible predatory pressure. This study confirms the existence of morphologically distinguishable populations of the little auk on Franz Josef Land and Svalbard, supported by recent studies of climatic and oceanographic conditions in the two areas that parallel the morphological differentiation. 相似文献
5.
J. CAMPSIE M. H. RASMUSSEN N. HANSEN C. J. LIEBE J. LAURSEN W. BROCHWICZ-LEVINSKI L. JOHNSON 《Polar research》1988,6(2):173-177
Age determinations for rock samples collected by Fridtjof Nansen during his trans-Arctic expedition from 1893-1896 have yielded additional information on the tectonic chronology of the Arctic Basin. The data suggest pulses of volcanic activity in the Frans Josef Land Archipelago with approximate averages of 120 ma and 135 ma. These ages are consistent with postulated opening dates for the western Arctic and thus suggest that initial volcanism affected the entire Arctic margin. 相似文献
6.
LECH STEMPNIEWICZ 《Polar research》1993,12(1):33-36
During the second half of August 1992 polar bears were observed feeding intensively in the little auk Alle alle colony on Rubini Rock, Hooker Island, Frans Josef Land. They dug out nests eating eggs, chicks and adult birds. Their activity results in both worsening the breeding conditions and decreasing the breeding success of the little auks. The polar bear has not earlier been known as a little auk predator. 相似文献
7.
MORTEN SMELROR 《Polar research》1987,5(2):221-238
Well preserved dinoflagellate cyst and acritarch assemblages are recorded from Upper Bathonian and Callovian deposits on Northbrook Island, Franz Josef Land. More than 45 species have been identified. Two new species are proposed: Parvocysta bjaerkei sp. nov., and Meiourogonyaulax spongiosa sp. nov. The recorded marine microfloras are compared with assemblages reported from contemporaneous strata in Svalbard. 相似文献
8.
P. J. Capelotti 《Polar research》2006,25(2):155-171
This next paper in Polar Research's series of not-formally-reviewed biographical/historical articles comes to us from anthropologist Pete Capelotti, who specializes in the history of exploration. In 1993, he conducted archaeological research on the base camps of the Andrée and Wellman polar balloon expeditions at Virgohamna, Danskøya, Svalbard. In this account of Walter Wellman's attempt to reach the North Pole from Franz Josef Land in 1898-99, he examines the lone success in that effort, when one American and four Norwegians discovered and explored the last large island in the archipelago. 相似文献
9.
《Norsk geografisk tidsskrift. Norwegian journal of geography》2012,66(1-2):33-38
Fridtjof Nansens innsats i polarforskningen er knyttet til to ferder: krysningen av Grønlands innlandsis i 1888, og den treårige drift med FRAM over Polhavet fra Nysibirøyene til Spitsbergen mellem 1893 og 1896. Strengt tatt bør vi tale om tre forskningsferder, ikke to, for sledereisen sammen med Hjalmar Johansen over drivisen i 1895, først i retning mot Nordpolen og derefter sydover til Frans Josef Land, var et foretagende for sig, en dristig krone på et verk som vilde ha bevart sin storhet selv uten dette lysende tillegg. 相似文献
10.
11.
A study of the whole-rock geochemistry and mineral chemistry of high-TiO2 Upper Jurassic and medium-TiO2 Lower Cretaceous basalts from Kong Karls Land, Svalbard, is presented. Geochemical criteria indicate that the basalts are initial rifting tholeiites with weak signs of crustal contamination. The Upper Jurassic basalts appear to be associated with the Olga Rift, part of a trans-Barents rift system which failed to link the proto-Atlantic and proto-Arctic basins. The Lower Cretaceous basalts may be more closely related to initial rifting tholeiites on Franz Josef Land and Spitsbergen generated during the rifting stage of opening of the Canada Basin. During break-up of the Barents Shelf, the sequence of magma types corresponds to the pre-, syn- and post-rifting stages established in other areas of continental break-up. Evidence for a possible hot-spot or plume trail, extending from Siberia to the Yermak Plateau over 250 Ma, is assembled. 相似文献
12.
Seabird colonies were censused during the summer expedition of Norsk Polarinstitutt to Nordaustlandet, Svalbard, in 1978 and 1979, and to Kongsøya in 1979. An outline is given of the distribution of the species together with an estimate of the number of breeding pairs in the colonies. Twentv-five colonies were censused; seven were visited both years. Four colonies with more than 1,000 breeding pairs of the most abundant species, Briinnich's guillemot and kittiwake, were found on Nordaustlandet. 相似文献
13.
The diet of high-arctic seabirds in coastal and ice-covered, pelagic areas near the Svalbard archipelago 总被引：3，自引：1，他引：3
Food samples from six high-arctic seabird species were collected during spring and summer seasons between 1982 and 1990 in the Svalbard region. The material came from coastal localities on the island of Spitsbergen and the marginal ice zone in eastern Svalbard waters. Polar cod Boreogadus saida was the most frequently occurring prey in the ice-covered areas. Analysis of otoliths showed that most polar cod were one-or two-year olds. These year classes are known to associate with sea ice. Other ice-associated (sympagic) organisms, such as gammarid amphipods, were not found to be of high importance as prey for seabirds in the study area. However, the sea ice occurring in the area was mainly one year old. Such ice contains a less developed sympagic fauna than multi-year ice. The pelagic amphipod Parathemisto libellula , which is not sympagic but occurs in the water column, was also found to be an important prey in the marginal ice zone, especially for the Briinnich's guillemot Uria lomuia . The smallest of the seabird species studied, the little auk Alle alle , differed from the other five species in its diet, preying mainly upon smaller items such as copepods and young stages of amphipods, euphausiids and decapods. The diet of the various seabird species was in general more diverse in the coastal areas than in the marginal ice zone. 相似文献
14.
Vladimir G. Dvoretsky 《Polar Science》2011,5(3):361-373
The spatial distribution of Calanus species was examined near Franz Josef Land archipelago in August 2006 and 2007. Surface and bottom water temperatures exceeded the average multiannual values. Calanus species dominated the total mesozooplankton abundance and biomass, accounting for 818 ± 178 individuals m−3 (mean ± SE) and 803 ± 163 mg wet weight (WW) m−3, respectively, in 2006. In 2007, the values were much lower (153 ± 29 individuals m−3 and 192 ± 17 mg WW m−3, respectively), reflecting the weaker influence of warm Atlantic water that year. Calanus glacialis dominated the Calanus populations, contributing 95% and 60% of the biomass in 2006 and 2007, respectively. Older copepodite stages (CIV–CV) predominated in the C. finmarchicus (69% and 76%, respectively) and C. hyperboreus populations (80% and 77%, respectively), whereas young copepodites (CI–CIII) were predominant in C. glacialis (45% and 59%, respectively). A clear negative relationship between the average water temperature and the total Calanus biomass was observed in 2006, whereas a positive correlation between these parameters was observed in 2007. The distributions of three Calanus species off Franz Josef Land were mainly associated with hydrological conditions and circulation patterns. 相似文献
15.
Late-and postglacial environments in the northern Barents Sea west of Franz Josef Land 总被引：1，自引：0，他引：1
A lithological and micropaleontological study of three sediment cores from the western Franz Josef Land area, two of them AMS l4 C dated, provides new data on the environmental evolution of the northern Barents Sea during and after the last deglaciation. Glacimarine conditions commenced in the deep Franz Victoria Trough by 13 kyr BP. and then presumably propagated into adjacent inter-island channels of Franz Josef Land. Pulses of Atlantic-derived water occurred during deglaciation and could have accelerated ice-sheet decay. Normal marine environments were established close to 10 kyr BP. Ameliorated conditions are recorded for the interval of approximately 9.5 to 5 kyr BP. After that, more severe environments existed probably associated with heavier sea-ice cover. 相似文献
16.
The oribatid mite Maudheimia wilsoni Dalenius was found to be numerous on the underside of stones at Jutulsessen (72°S, 3'E) in Dronning Maud Land, Antarctica. Daily temperature fluctuations of the microhabitat from as high as 19°C and to as low as – 17°C were observed during the austral summer. Optimal activity of the mites occurred at 10°C. Even in January the mean supercooling point of adult mites was as low as -30.8±4.7°C. Haemolymph osmolality ranged from 500 to 800mOsmol and thermal hystersis freezing points from −4.7 to −6.1°C. Adult mites had a mean water content of 43.6% and a water loss rate of 0.12 μgh−1 at 15°C and 10% relative humidity. 相似文献
17.
Concentrations (ppm = ug/g dry weight) of total mercury (Hg) were determined in hair of polar bears ( Ursus maritimus) from northwestern Greenland (N = 22; period of sampling: 1978-1989), eastern Greenland (N = 44: 1984-1989) and Svalbard (N = 31; 1980). For subadults (2-6 years of life), adults (7-10 years). and old bears (>10 years), concentrations of total Hg in hair were not found to be dependent on age or sex. A decreasing trend in Hg concentrations was found from west to east. The mean concentrations of total Hg in hair (cubs of the year and yearlings excluded) were: northwestern Greenland, x = 8.38 ppm (min.-max.: 4.71-14.19 ppm. N = 21); eastern Greenland: x = 4.58 ppm (min.-max.: 2.50-8.83 ppm. N = 41); and Svalbard, x = 1.98 ppm (min.-max.: 1.02-4.55 ppm, N = 29). Concentrations found in northwestern Greenland were similar to those reported by others from the hair of polar bears sampled within management zone F of the eastern Canadian High Arctic. Concentrations of total Hg in polar bear hair from eastern Greenland were similar to concentrations found by others in contemporary (1988) material collected during spring in western Svalbard. However, the mean concentration of total Hg in the 1980 Svalbard material, which was collected during July-September, was significantly lower than concentrations found in samples taken during late winter and spring in eastern Greenland and at Svalbard, respectively. Presumably the relatively low concentrations found in the 1980 Svalbard sample arc attributable to the period of moult and hence a larger proportion of newly grown hair in the individual samples. In a subsample consisting of internal tissues from 19 polar bears from eastern Greenland (1984-1987), concentrations of total Hg in hair correlated positively with concentrations of total Hg (wet weight) in muscle (N = 6), liver (N = 19) and kidney (N = 19) tissue. For liver and kidney tissue these relationships were statistically significant. 相似文献
18.
Palaeomagnetic investigations and Rb–Sr dating were carried out on samples from two plutons from the Granite Harbour Intrusives of the Transantarctic Mountains inland of Terra Nova Bay. The Rb–Sr whole rock–biotite ages from Teall Nunatak (475±4, 483±4 Ma), a quartz-diorite pluton cropping out to the south of Priestley Glacier, are older than that from the Mount Keinath monzogranite (450±4 Ma), which is located to the north of the glacier. These results are consistent with the literature data, which suggest that during the last phases of the Ross Orogeny the cooling rate of the basement was significantly lower to the north than to the south of Priestley Glacier. The Teall Nunatak quartz-diorite is characterized by a stable magnetization, whose blocking-temperature spectrum ranges from 530 to 570 °C. At one site, the stable magnetization is screened by a large secondary component of opposite polarity, removed by thermal demagnetization below 300 °C. The characteristic directions after thermal demagnetization yielded a southern pole located at lat. 11°S, long. 21°E. The magnetization of Mount Keinath monzogranite consists of several components with overlapping stability spectra. A characteristic direction was isolated at one site only, obtained by demagnetizing the specimens in the temperature range from 380 to 460 °C.
Comparison with the other East Antarctica poles shows that those from Victoria Land are very well grouped and give a reliable early Ordovician palaeopole (lat. 5°S, long. 23°E, with K =196 and A95 =3.7°), whereas the poles from Wilkes, Enderby and Dronning Maud Land are dispersed. We tentatively advance the hypothesis that the dispersion reflects different magnetization ages due to the slow cooling of these regions during the last stages of the Ross Orogeny. 相似文献
Comparison with the other East Antarctica poles shows that those from Victoria Land are very well grouped and give a reliable early Ordovician palaeopole (lat. 5°S, long. 23°E, with K =196 and A
19.
Naoya Wada 《Polar research》1999,18(2):261-268
To determine the factors restricting plant reproduction in front of a glacier, the gender expression and seed production of Dryas octopetala L. (Rosaceae) were observed, as well as the grazing pattern of reindeer on flowers, near Brøggerbreen (Brøgger Glacier), which is near Ny-Ålesund (78° 55'N, 11° 56'E), Svalbard. Three hundred shoots with flowers and flower buds were randomly tagged in early July 1996. Between then and the end of flowering in late July, 100 (33%) flowers and buds were grazed by reindeer. Out of the surviving flowers, 145 (76%) shoots had hermaphrodite flowers, while 45 (24%) shoots had male flowers without a developed gynocium. Male flowers, which appeared later than hermaphrodite flowers in the population, were significantly smaller than hermaphrodite flowers in dry weight. In the hermaphrodite flowers, moreover, smaller flowers showed lower dry-weight allocation to the gynoecium as compared to larger flowers. During the observation, hermaphrodite flowers did not produce any developed seeds under a natural condition (0% seed-set). Cross-pollinated flowers showed 8% seed-set. On the other hand, flowers which were artificially warmed in small greenhouses during the flowering period showed 60% seed-set, regardless of cross-pollination or autodeposition of pollen from anthers to stigma (self-pollination). Thus, it was found that grazing, gender variation in relation to the length of the growing season and the flower size, and - in the floweriing period - low temperature rather than pollinator limitation strongly affected the seed production of D. octopetala in the population studied. 相似文献
20.
OTTO SALVIGSEN LENA ADRIELSSON CHRISTIAN HJORT MICHAEL KELLY JON Y. LANDVIK LARS RONNERT 《Polar research》1995,14(2):141-152
Glacial striae and other ice movement indicators such as roche moutonées, glacial erratics, till fabric and glaciotectonic deformation have been used to reconstruct the Late Weichselian ice movements in the region of eastern Svalbard and the northern Barents Sea. The ice movement pattern may be divided into three main phases: (1) a maximum phase when ice flowed out of a centre east or southeast of Kong Karls Land. At this time the southern part of Spitsbergen was overrun by glacial ice from the Barents Sea; (2) the phase of deglaciation of the Barents Sea Ice Sheet, when an ice cap was centred between Kong Karls Land and Nordaustlandet. At the same time ice flowed southwards along Storfjorden; and (3) the last phase of the Late Weichselian glaciation in eastern Svalbard is represented by local ice caps on Spitsbergen, Nordaustlandet, Barentsoya and Edgeøya.
The reconstructed ice flow pattern during maximum glaciation is compatible with a centre of uplift in the northern Barents Sea as shown by isobase reconstructions and suggested by isostatic modelling. 相似文献
The reconstructed ice flow pattern during maximum glaciation is compatible with a centre of uplift in the northern Barents Sea as shown by isobase reconstructions and suggested by isostatic modelling. 相似文献