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1.
Elemental composition of some species of mushrooms from Ust’-Koksa raion, Gorny Altai, was analyzed to identify species that accumulate the highest concentrations of heavy metals and to estimate the ecological state of the area. The method of X-ray fluorescence analysis using synchrotron radiation was employed.  相似文献   

2.
New bryozoans Saffordotaxis altaicus sp. nov. from the Givetian Stage (Middle Devonian) and Cyphotrypa olgae sp. nov. and Crustopora aliena sp. nov. from the Famennian Stage (Upper Devonian) are described from the Devonian of Gorny Altai.  相似文献   

3.
The high-mountain Chuya depression (Gorny Altai) was studied in 2006–2008. New data on the diversity of soil components of the soil cover in terms of the new Russian soil classification system have been obtained. Some relations of soil components to biotic and abiotic components of high-mountain steppe terrestrial ecosystems have been revealed.  相似文献   

4.
Ostracodes from the Tuloi (Floian, Dapingian and the lower Darriwilian) and Karasu (Darriwilian and Sandbian) formations of the northeastern Gorny Altai are discussed and several ostracode localities are briefly described. Two new species Soanella tuloica sp. nov. and Maraphonia caliginosa sp. nov. are described and figured. The previously described forms are only illustrated.  相似文献   

5.
Ostracodes from the Gur'yano-ka Formation (Upper Ordo-ician, Sandbian and Katian stages) of Gorny Altai, Russia, are studied for the first time. Some localities with fossil ostracodes of this age are described briefly. Ele-en new species of the genera Ballardina, Eurychilina, Laccochilina, Bolbina, Retiprimites, Pseudozygobolbina, Bullaeferum, Soanella, Egoro-ella, and Allertemmysa are described and figured. The pre-iously described species Leperditella aff. par-ipunctata V. Ivanova, 1959, Grammolomatella valdari V. Ivanova et Melnikova 1977, Longidorsa? baltica Meidla, 1996, and Steusloffina cuneata (Steusloff, 1895) and ostracodes in open nomenclature, Bollia sp., Klimphores sp., Rectella sp., Longiscula sp., are only figured.  相似文献   

6.
The strata of the Permotriassic Trappean Complex of Siberia (Ilimpeya River and Kapchan locality) are studied. The water-lava and water-tuff boundaries are shown to be promising for bacterial paleontological studies. The analysis of fossilized microbial communities shows that they vary depending on sedimentation conditions. This example is important for a better understanding of the prospects for the study of similar situations in the Archean and Proterozoic.  相似文献   

7.
Gradual dispersion of an abundant flea species Ctenophyllus hirticrus specific to the Pallas's pika (the main plague carrier), is revealed in the Gorno-Altai natural plague focus on the territory, occupied by two populations of this lagomorph. Spreading of Yersinia pestis in these areas took place a short time later the rise of this ectoparasite's abundance. It is supposed that the colonization of these areas by C. hirticrus was one of the factors determined epizooties spreading within the focus and formation of new sites of stable Y. pestis preservation.  相似文献   

8.
9.
Six distinct bryozoan paleobiogeographical provinces existed during the Silurian of North America, Baltica and Siberia. These provinces are based on parsimony analysis of endemicity (PAE), each supported by a number of endemic genera only present in that assemblage. The area cladogram displays a nested pattern, permitting the clustering of assemblages into larger units that might be indicative of their areas of origin. Paired-group cluster analysis supports the existence of provincial assemblages. Relationships indicate the action of both vicariance and geodispersal. Geographic boundaries between the provinces include land, deep sea, and climate zone boundaries, including barriers created by the Iapetus Ocean and the Tornquist Sea.  相似文献   

10.
Eight bryozoan species of the order Cystoporida are described from the Emsian Stage of the Lower Devonian in the western Altai-Sayan Folded Area. Five of them are new species: Fistulipora salairiensis sp. nov., Fistuliramus fasciculus sp. nov., Fistuliphragma sibirica sp. nov., F. moniliformis sp. nov., and Fistulocladia cincinnata sp. nov. The others belong to the genera Ganiella, Physallidopora, and Fistuliporidra. Most of the cystoporid species studied from the Emsian Stage in the Altai-Sayan Folded Area are widespread laterally. Six cystoporid species have a narrow stratigraphic range and are, therefore, characteristic species of the bryozoan biostratigraphic zones of this region. The species of Physallidopora cantabrica Ernst et Buttler and Fistuliporidra hibera Ernst et Buttler, for the first time encountered in the Emsian of Gorny and Rudny Altai, were previously described from coeval deposits in northwestern Spain.  相似文献   

11.
The distribution of stomatocysts of chrysophyte algae in the plankton of bodies of water of different types in the basin of the middle reach of the Irtysh (at the Omsk Region), as well as in the plankton and in fouling of the deep-water oligotrophic lake Teletskoe (Gorny Altai) has been considered. The classification of morphotypes of stomatocysts has been carried out. The number of morphotypes found in plankton samples from bodies of water of the middle Irtysh basin is 30 and, in Lake Teletskoe, 60. Four similar morphotypes of cysts were revealed for the bodies of water under investigation.  相似文献   

12.
Relatively well-preserved polycystine Radiolaria are here described from Lower Cambrian (Botomian) strata of the Shashkunar Formation, Altai Mountains in southern Siberia (Russia). These radiolarians display a test formed of a disorderly and three-dimensionally interwoven meshwork of numerous straight and curved bars branching from a five-rayed point-centered spicule located within the inner shell surface. The shell structure allows their assignment to the family Archeoentactiniidae, thus extending the known age range of the family down to the Lower Cambrian. The Botomian age is based essentially on trilobites (Parapagetia-Serrodiscus zone), but also on archaeocyathids identified in earlier publications. The study of the radiolarian-bearing sedimentary sequence confirms the presence of polycystine radiolaria in the external platform environments of Lower Cambrian ecosystems.  相似文献   

13.
The molecular composition of lipids in three samples of leafy mosses (Aulacomnium palustre, Warnstorfia fluitans, and Calliergon giganteum) has been determined. The revealed acyclic compounds included normal and isoprenoid alkanes, isoprenoid alkenes, normal and isoprenoid ketones, carboxylic acids and their esters, alcohols, and aldehydes. Among cyclic compounds, bi-, tri- and tetracyclic polycycloaromatic hydrocarbons (PAHs), bicyclic and pentacyclic terpenoids, steroids and tocopherols have been observed. The identified organic compounds consisted mainly of carbocyclic acids and n-alkanes with the prevalence of C27 homologues. A. palustre is characterized by a reduced content of isoprenoid compounds, alcohols, and ketones, while the content of unsaturated acids, pentacyclic terpenoids, and aldehydes is rather heightened. A. palustre differs from W. fluitans and C. giganteum in the steroid composition and contains eremophylene, a sesquiterpenoid, which is absent in the mosses of the family Amblystegiaceae. Compared to C. giganteum, W. fluitans has a higher content of lycopadiene, carboxylic acids, n-alkanes, phyt-2-ene, aldehydes, esters, squalene, diploptene, α-tocopherol, and triphenyl phosphates.  相似文献   

14.
Dzhangyskol is a small lake of glacial origin in the central part of the Altai Mountains in southern Siberia. Pollen stratigraphies and chronologies of two cores record the vegetational development of the area from the Late Glacial treeless landscape to the forest and steppe of today. The modern lake is a remnant of a much larger ice-dammed lake, which was reduced in size and then temporarily drained after diversion of the inflowing mountain meltwater stream, which had low δ18O values. The dry lake floor allowed development of permafrost and small pingos (frozen mounds of lake sediments). With the onset of greater climatic humidity in the mid-Holocene, the input of local water with higher δ18O caused a rise in lake level, drowning the earlier pingos. Growth of a broad fen on the margin of the lake led to formation of a modern pingo complex.  相似文献   

15.
Enrichment cultures of sulfate-reducing bacteria were obtained by inoculating the water of high-temperature gas and oil-bearing strata. A study of the morphology of these cells has shown that the thermophilic bacterium Desulfovibrio thermophilus occurs in the deposits of the Apsheron Peninsula while Desulfootomaculum nigrificans is found in the deposits of West Siberia. The former organism is involved in the accumulation of H2S in the Apsheron strata. The temperature of the strata is believed to be the factor which regulates the incidence of bacteria.  相似文献   

16.
The presence of one of the oldest records of polycystine Radiolaria in the Lower Cambrian sedimentary sequence of the Ak-Kaya section (Gorny Altai) requires a biostratigraphic dating. The trilobites found recently a few tens of meters below the radiolarian-bearing level belong to Calodiscus resimus Repina, Serrodiscus fossuliferus Repina and Alacephalus aff. contortus Repina; they suggest that this part of the Shashkunar Formation can be correlated with the lower part of the Botomian stage. The absence of eyes in the two former species suggests a mode of life buried in the fine pelagic sediments. Indications of the presence of a strongly developed musculature on the third species point to a palaeoenvironment characterized by a relatively high hydrodynamic regime.  相似文献   

17.
18.
Pyrite is present in many horizons in dark grey graptolite-rich shales of Llandovery-early Wenlock age on the island of Bornholm, Denmark. The pyrite usually occurs as internal moulds of the graptolites, but rarely on the outside of the periderm. Occasionally the internal pyrite protrudes from the apertures of the rhabdosomes. Investigations using reflected light and scanning electron microscopy have shown that the internal pyrite is texturally variable. The abundance of the framboids is variable, ranging from thin linings on the inner side of the periderm to nearly complete infills of the graptolite colony. The pyrite also occurs as densely packed microcrystals and as larger euhedral crystals in all transitions from individual crystals, often developed on the surfaces of the framboids. to compact aggregations. Some of the pyritized graptolites have central cavities in the rhabdosomal linings. Within the cavities there are striking stalactite-like forms of pyrite suspended from the roof of the periderm. Some specimens have late infillings by calcite in the central part of the tubes. Most of the internal pyrite must have been formed very early during the taphonomic processes operating on the graptolites, pre-dating the compaction of the sediment. The framboids were first precipitated, followed by the aggregated euhedral pyrite. It is debatable whether the tubes of the graptolites were fluid-filled or partially gas-filled when the stalactites were formed; the latter is the more likely. The beds with fully pyritized graptolites might represent an episodic increase of sedimentation rate and oxygen content of bottom waters. □ Pyrite, Silurian, graptolites, Bornholm, stalactites, early diagenesis.  相似文献   

19.
The jaws of the new polychaetaspid polychaete, Oenonites? honki, from the Silurian of Gotland, Sweden, differ from most Palaeozoic polychaete jaws. They exhibit enigmatic microstructural features in that they appear rough and give a corroded, or weathered impression. The altered microstructure of the jaws suggests a jaw chemistry and/or composition differing in some way from that of the co‐occurring polychaete taxa. The jaws appear to have limited preservational potential and/or were particularly susceptible to secondary processes, resulting in microstructural alteration. Commonly, a row of distinct pits occurs on the outer face, especially of the first right maxillae (MIr). Because these pits are interpreted as associated with the dentary, the term ‘denticle marks’ is suggested. The pits may be the result of primary or secondary physical wear, or, more probably, secondary chemical alteration of localized mineral deposits. The primary function of such mineral deposits was to harden those parts of the surface that were exposed to great stress. The restricted occurrence of O.? honki, coupled with occasional increases in abundance (especially in the Halla Formation, unit b), indicates a preference for shallow marine, high‐energy environments, particularly in reefal pockets with calcilutitic sediments. Highest frequency coincides with faunas characteristically containing a few labidognath species also displaying high frequencies.  相似文献   

20.
Two pollen diagrams from near the Chuya Basin, Russian Altai, are presented together with results from geomorphological archives. The Kuray Range profile (2330 m a.s.l.) is situated just above the forest line and starts with the weak cooling of the middle Atlantic period (ca. 6500–5900 b.p.) that bisects the Holocene optimum, as in other parts of Siberia. Taiga (boreal coniferous forest) with Picea obovata established afterwards but was displaced at ca. 5300 b.p. by the pronounced cooling of the early Sub-boreal. A gradual recovery of taiga stopped and it disappeared around 3400 b.p. at the end of the middle Sub-boreal. Since then the climatic and vegetational conditions much resemble those of the Sub-atlantic. In the last two millennia, three climatic declines are documented in the second diagram from the Tarkhata Valley (2210 m a.s.l.) from the dry limit of Larix sibirica: a cold and wet one around the 5th century a.d., a cold and dry one around a.d. 1200 and the Little Ice Age which started around a.d. 1600. In addition, several of the climatic periods and especially local human influence can be proved by the geomorphological findings. Most of the climatic changes seem to be connected with socio-ecological changes in Asia and even Europe, with movements of the Huns and Mongols, which show the possible dimensions of global climatic change. Hints of teleconnections between Siberia, the Mediterranean and the Himalayas via the North Atlantic and the Arctic Oscillation are discussed.  相似文献   

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