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An abundant early Silurian brachiopod assemblage of 14 species, with strong affinities to the early Rhuddanian faunas of Britain and Baltoscandia, was recovered from the Akkerme Peninsula, on the western side of Lake Balkhash, southern Central Kazakstan. The occurrence of Stricklandia lens mullochensis, which is ttre earliest member of the Stricklandia-Costistricklandia lineage, dates this brachiopod assemblage as early Rhuddanian, within a stratigraphic interval from the Akidograptus acuminatus to the lower part of the Monagraptus cyphus graptolite biozones. This is the first well documented record of early Rhuddanian brachiopods in Kazakhstan. The assemblage also includes Meifodia tulkulensis sp. nov. and Eospirifer cinghizicus with well preserved spiralia. The co-occurrence of Stricklandia lens mullochensis and Eospirifer cinghizicus has not been recorded previously and is regarded here as the most signiffcant difference between the early Rhuddanan brachiopod faunas of the Baltic (East-European) Plate and Britain; in contrast Eospirifer first appears in the two latter areas in the late Llandovery.
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Central Kazakhstan is frequently referred to as a hypothetical Paleozoic continent Kazakhstania, although its geological structure suggests that in the early Paleozoic it was either a series of island arcs or microcontinents separated by small oceanic basins, each having its own history of development. The cherty and volcanogenic-cherty deposits of the south-western Predchingiz Region and the North Balkhash Region in central Kazakhstan represent an ophiolite rock association with pelagic sediments. The Early-Middle Ordovician conodonts found in the cherty rocks are the only fossils useful for precise dating of the strata and for interpretation of the palaeobiogeographic relations. A low taxonomic diversity is typical of conodonts from these pelagic sediments. Most of them are of the Baltic type, and only some, like Paroistodus horridus and Histiodella tableheadensis, represent other, apparently more warm-water faunal elements. Deep-water conodont faunas from central Kazakhstan are coeval with the Early-Middle Ordovician conodonts from the shelf deposits of southern Kazakhstan, but the latter are taxonomically more diverse and contain warm-water forms (e.g., Juanognathus variabilis, Reutterodus andinus, Serratognathus bilobatus, and Bergstroemognathus extensus). This corroborates the idea that Kazkhstania was closer to the equator, than to the Baltic region in the Ordovician.
The topic of forest plantations is particularly important in countries with low forest cover, where the demand for wood is particularly high, such as e.g. Kazakhstan. The main goal of this paper is to present the results of research on the productivity of selected cultivars of poplar: 62027−1 hybrid and Kazakh poplar, grown in various spacings (2,5×1, 3×1,5 and 3×2 m, which translates to stocking of 4000, 2220 and 1667 trees per ha, respectively), and the possibility of their cultivation in the conditions of southeastern Kazakhstan. The conducted experiments confirmed the high production potential of the selected hybrid poplars. The average volume of the individual trees' trunks at the age of 23 years reached 0,4−0,5 m3, the total growing stock can be up to 800−1000 m3/ha and the mean annual increment from 29 to 44 m3/ha. More adapted to the local conditions proved to be hybrids belonging to a section of white poplars. Due to dying tree tops and signs of damage from insects emerging at age exceeding 22−23 years, observed especially in plantations consisting up of hybrids belonging to the black poplars section, plantation rotation should not exceed 20 years. Establishing the poplar plantations using selected varieties is also one of the promising ways for reclamation of the saline soils of south−eastern Kazakhstan. Along with the timber and the possible use of biomass, plantations can be also used as a source of feed and hay for livestock.
The research was carried out in the economic and natural Forest Reserve ‘Yertys Ormany’ in Pavlodarsk Oblast (Kazakhstan) in 2018. In the middle of May, two barrier traps of the ‘Netocia’ type (30, in total) were installed on each research plot damaged by wind, fire and great pine web – spinning pine sawfly – Acantholyda posticalis Mats. Insects were caught every month, from mid−June to mid−August. 1521 insects belonging to 67 species and 23 families were caught in the traps. Beetles clearly dominated. We also observed a great pine web and sirex woodwasp Sirex noctilio Fabr. Of the beetles caught, 10% were thermophilic jewel beetles or metallic wood−boring beetles Buprestidae, among which Chalcophora mariana (L.) dominated. The highest average number of individuals was observed on sites damaged by A. posticalis, however, differences between the plots turned to be insignificant. The highest significant average number of species was observed on sites damaged by the fire and by the wind. The GLM analysis indicated the highest mean values of the Margalef index in plots damaged by fire and by the wind, but did not show significant differences between the average values of the fidelity index of the assemblages. The research confirmed the hypothesis of a greater number of species and individuals, and a higher diversity of pests in pine stands more strongly disturbed (i.e. damaged by the fire and by the wind). At the same time, there were no differences between the most seriously disturbed variants.
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