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1.
Metabolic rates and Q10 values were determined for three species of Spitsbergen Coleoptera, Amara quenseli, Simplocaria metallica and Rhynchaenus flagellum . The beetles had metabolic rates which were elevated compared to values of Coleoptera from other regions. This is interpreted as an adaptation to the prevailing low temperatures and short activity period on Spitsbergen.
A. quenseli had rates of water loss comparable to values of beetles in temperate and tropical xeric habitats, indicating that the habitat of the beetles on Spitsbergen at least occasionally is xeric.
Determination of cold-hardiness parameters such as supercooling point and haemolymph melting point of A. quenseli beetles revealed that the beetles had values corresponding to those of active insects in the temperate and tropical region. They had no thermal hysteresis factors. Thus, during summer they show no physiological adaptations to cold.  相似文献   

2.
Heavy metals and sulphur in mosses from southern Spitsbergen   总被引:1,自引:0,他引:1  
Concentrations of Cd, Pb. Ni, Cu. Zn and S were determined in 16 moss species collected from 9 localities in southern Spitsbergen (mostly within the Hornsund region). Two species, Sanionia uncinata and Hylocomium splendens , were objects of more thorough studies. In Sanionia uncinata the mean concentrations were (ug/g): Cd-0.59, Pb-7.07, Ni-4.25, Cu-6.01. Zn-21.13 and S- 1, 481. Hylocomium splendent accumulated similar quantities of these elements. The concentrations of metals and sulphur in mosses differed significantly {p 0 .05) from site to site, depending on geological and climatic conditions specific to the Arctic region. The effect of remote sources of pollution reaching Spitsbergen on the levels of heavy metal concentrations was taken into account, as well as the effect of local emissions from the Polish Polar Station. At 10-25 metre distances from the Station, the levels of heavy metals and sulphur were 3-10 times higher than at a 300-metre distance.  相似文献   

3.
Biostratigraphic evidence for the age of Tertiary formations on Spitsbergen is critically reviewed and new evidence from dinoflagellates is presented. The shift in basin geometry and sediment source area observed in the Gilsonryggen Formation is dated as latest Palaeocene, coinciding with the initial opening of the Norwegian Sea at anomaly 24–25 time. An Upper Eocene age is proposed for sediments from Forlandsundet (Sarsbukta), indicating that the Forlandsundet graben was created during the phase of shear movement between Greenland and Spitsbergen before anomaly 13 time.  相似文献   

4.
Formålet med ekspedisjonen til Spitsbergen sommeren 1930 var en inngående undersøkelse av den mesozoiske lagrekke i Isfjordområdet. Denne undersøkelse, som av Norges Svalbard- og Ishavsundersøkelser blev overdratt mig, var ønskelig for å kunne supplere de resultater, som var opnådd på de tidligere Spitsbergenekspedisjoner.

Vi reiste fra Harstad 2. juli med kulldamperen »Inger Elisabeth« og kom til Longyearbyen 5. juli. Opholdet på Spitsbergen varte til 26. august da man forlot Adventfjorden med en kulldamper.

Undersokelsene blev foretatt på ostkysten av Nordfjorden (Dicksonlandet) ved Sassenfjorden, Adventfjorden, Gronfjorden og i omradet mellem Festningen og Russekeila. Der blev arbeidet i den sakalte perm, i trias, jura og krittformasjonen.

Fra disse lag forela der allerede et ganske betydelig materiale, for storste delen innsamlet på Hoels ekspedisjoner og bearbeidet av mig. Meget nytt om stratigrafien og mesozoikums faunistiske forhold var derved fremskaffet, men like mange nye sporsmal blev reist, særlig angaende de forskjellige horizonters gjensidige beliggenhet og og deres plass i andre områders stratigrafiske system.  相似文献   

5.
The occurrence of macromolecular antifreeze agents (so-called Thermal Hysteresis Factors) in blood plasma of fishes from Spitsbergen waters was investigated in August 1983, October 1984, and January 1986.
Thermal hysteresis was found in the plasma of three species of Spitsbergen fishes: shorthorn sculpin (Myoxocephalus scorpius) , polar cod (Boreogadus saida) , and sea snail (Liparis liparis) . This is the first time thermal hysteresis is reported from the sea snail. Seasonal changes in the amount of thermal hysteresis were observed in blood plasma of the shorthorn sculpin and the sea snail.
With the exception of the polar cod, blood plasma of deep water fishes displays no thermal hysteresis. The reason for this is probably that the polar cod also occurs in shallow ice laden sea water, where an'antifreeze'would be needed to protect against inoculative freezing.
No thermal hysteresis was observed in blood plasma of the saithe (Pollachius virens) , despite the fact that the saithe was observed swimming in ice laden sea water at a temperature of -1 to – 1.5°C under natural conditions, and was rapidly killed when it came into contact with ice in the laboratory. It is not known how the saithe survives in ice laden water under natural conditions.  相似文献   

6.
7.
Glacierkarst is a common phenomenon on Spitsbergen. The Spitsbergen glaciers circulate large amounts of liquid water, even during the polar winter. Investigations have revealed two types of drainage systems: marginal drainage canals and central drainage canals. Marginal drainage canals are located within the medial moraines or between the glacier margin and the unglaciated valley slope. Lengths up to 1 km and diameters of 10 m are known. The marginal drainage canals are often founded on solid bedrock. The central drainage systems are less well understood, but are located within the glacier mass, founded on ice. The two types of drainage canal systems contain many features associated with classic calcareous karst, such as phreatic tubes, vadose canyons, dripstones (in ice), multilevel development and integrated drainage. Surface analogs such as dry valleys, uvalas, ponors and poljes also exist. Conduits are found as much as 40 m below the ice surface.  相似文献   

8.
Light-photosynthesis curves for 9 species of benthic algae from the Hornsund fiord were determined. As a result of adaptation to the conditions in the Arctic, benthic algae from Spitsbergen have a low requirement of light. Saturation and compensation points are low and within a range typical for shadow-tolerant plants.The values for gas exchange rates indicate that Arctic algae have lower photosynthctic capacity than temperate species.  相似文献   

9.
The sandstone petrography of sample suites from four sites spanning the Rurikfjellet (Hauterivian) to Carolinefjellet (Aptian-Albian) formations in central Spitsbergen was investigated. The sandstones show a distinct stepwise shift in composition from quartz arenites to sublitharenites and lithic arenites, typically within the upper part of the Helvetiafjellet Formation. This shift is related to the introduction of 10 - 25% (grain%) plagioclase grains and volcanic lithics, and a notable increase in basement and sedimentary lithics. Quartz grain character also changes, and grain shapes become more varied. The shift is also associated with the transgressive arrival of marine sediments in the area, and the introduction of sands from the east-northeast by shore-parallel transport. Regional regression and subsequent transgression, and the change in sandstone composition is attributed to the development of the High Arctic Large Igneous Province in the region. The relative constancy of sand composition and volume of volcanic detritus within the Carolinefjellet Formation suggests long term (∼20 M) stability of the sediment system and a large volcanic source area, consistent with LIP (Large Igneous Province) derivation, along with significant exposure of basement rocks. Sample spacing and sediment recycling and mixing do not allow detection of events that would have changed sandstone composition that were less than ∼1 M duration. Preservation of significant amounts of plagioclase in a sediment-starved shelf can be explained by relatively cold climatic conditions.  相似文献   

10.
11.
Seven samples from the Limestone and Boulder Conglomerate Members of the Bulltinden Formation have yielded poorly preserved conodonts. On tentative identifications Periodon aculeatus Hadding and Prioniodus cf. P. alobatus Bergstrom at the base of the formation suggest an Ordovician lower Caradoc, or older age. This confirms that the Vcstgotabrcen Formation unconformably beneath underwent high-pressure mctamorphism during the Taconic and/or Finmarkian phases of the Caledonian orogeny. The conodonts show affinity to the North Atlantic Province suggesting a deeper water marine depositional environment. Conodont colour alteration indices of five indicate that the Bulltinden Formation was heated to temperatures in excess of 300°C, probably during the middle-upper Silurian main Caledonian uplift event.  相似文献   

12.
Pyroclastic material of a rhyolite type is present in some thin layers in the upper part of the De Geerdalen Z Formation in the Sassenfjorden area. This is the first evidence of late Triassic (Norian Rhaetian) volcanic activity in Svalbard.  相似文献   

13.
Analysis of benthic foraminiferal assemblages was performed in Bathonian to Kimmeridgian deposits through a section covering the lower half of the Agardhfjellet Formation in central Spitsbergen. The section consists mainly of organic-rich shales, which contain low-diversity agglutinated assemblages. In this foraminiferal succession five morphogroups were differentiated according to shell architecture (general shape, mode of coiling and number of chambers), integrated with the supposed microhabitat (epifaunal, shallow infaunal and deep infaunal) and feeding strategy (suspension-feeder, herbivore, bacterivore, etc.). The environmental evolution of the analysed section is interpreted by using the stratigraphic distribution of morphogroups, combined with species diversities and sedimentary data, in a sequence stratigraphic framework. The section comprises two depositional sequences, which demonstrate that species diversity and relative frequency of morphogroups are correlative with transgressive–regressive trends controlling depth and oxygenation of the water column. In both sequences, the maximum flooding interval is characterized by increased organic carbon content, dominance of the epifaunal morphogroups and reduced species diversity: features reflecting the increased degree of stagnation separating the transgressive phase from the regressive phase.  相似文献   

14.
A rich Kimmeridgian ammonite fauna is described from the Janusfjellet Subgroup at Holmgardfjellet, Agardhbukta, East Spitsbergen. The fauna collected from a narrow stratigraphic interval represents a single ammonite assemblage showing a wide but continuous range of variability, with end-forms strongly resembling Amoeboceras (Hoplocardioceras) decipiens Spath and A. (Amoebites) elegans Spath, respectively. Accepting a horizontal classification in ammonite taxonomy, the assemblage may easily be placed into a single species for which the name Amoeboceras (Amoebites) uralense Mesezhnikov, 1973, is available, as this form corresponds to the intermediate and the most common morphotype. The fauna with A. uralense is possibly directly below that with A. elegans and A. decipiens , but above that with A. kochi . Close phyletic relations are suggested between the A. elegans - A. uralense group (traditionally placed in the subgenus Amoebites) and the subgenera Hoplocardioceras (type species A. decipiens) , and Euprionoceras (type species A. kochi).  相似文献   

15.
Aristoptychites kolymensis (Kiparisova) is investigated and described in detail from collections made at Botneheia, Spitsbergen, where it occurs at the top of the Botneheia Formation (Daonella Shale). It is a rather small species and the stratigraphically highest representative of the genus in Spitsbergen. Its suture line is remarkable by its possession of the additional U.-lobes between the internal lobe and the first umbilical lobe. A lobe of this kind has so far been described only once, with Arcestes (Proarcestes) bicarinatus by Schindewolf (1968), which suggests affinities between Ptychitidae and Arcestidae.  相似文献   

16.
17.
Soils at well-drained sites near Kongsfjorden, Spitsbergen, are described in terms of morphology as well as solid and solution phase chemistry. Decarbonation is the dominant soil process and results in high Mg and Ca concentrations in soil solutions, in negative enrichment of Fe, Al, and non-carbonate clasts in near-surface horizons, and in the accumulation of dolomitic silt horizons at depth. Coatings of reprecipitated carbonates extend into the C horizon. Several developmental pathways are suggested for well-drained carbonate soils at Kongsfjorden. In vegetation-rich areas, with calcite-rich parent material, relatively rapid (∼ 10, 000 years) carbonate dissolution precedes silicate mineral weathering. In areas of Polar Desert climate and dolomitic parent material, decarbonation is slower and the continued accumulation of dolomite silt may eventually transform the soil system to a periglacial one.  相似文献   

18.
Three radiocarbon dates on marine organic material from southernmost Spitsbergen are presented, making it possible to compare the Holocene shoreline displacement in this area with that of other areas of Svalbard. The most distinct raised beach feature is the large beach ridge terrace about 10 m above sea level which most probably is the result of a marine transgression ca. 6500 years ago. Dating of 2700-year-old laminaria from about 2 m above sea level demonstrates a small rising of the land during the youngest Holocene.  相似文献   

19.
During the period August 1981 to July 1982, samples of six species of Amphipoda common to Hornsund were collected, and a study of their energy value changes was carried out. Only slight fluctuations of energy values were observed throughout the year, and no distinct seasonal changes as in the case of boreal organisms. Individuals of greater body size exhibit higher energy values. The lowest energy values 10.93 kJ g−1 d.w. (SD = 3.01) and highest ash contents 29.8% (SD = 7.6) were found in small Amphipoda (e.g. Ischyrocerus anguipes) , while species attaining greater body size were characterized by higher energy values and lower ash contents, for example Gammarellus homari 16.96 kJ g−1d.w. (SD = 0.50), and 22.9% (SD = 3.3%) ash.  相似文献   

20.
Concentrations of heavy metals Zn, Mn, Cu, Fe, Ni, Cr, Pb, Cd, Hg and Co were determined in surface waters, glacier ice and plant and animal materials from three regions in Spitsbergen, Svalbard. The concentrations of these metals in two samples of surface waters and in the vascular plants from Spitsbergen were found to be lower than what is commonly found in Cental Europe. Elevated concentrations were found in old ice from the surface of a glacier. The concentrations of heavy metals in algae were lower than in vascular plants. The concentrations of metals in the samples of feathers and animal hair from Spitsbergen were higher than what is common for Central Europe.  相似文献   

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