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1.
Fedorov GM 《Soviet geography》1983,24(4):289-297
"Oblast-level regions of the USSR are grouped and mapped in nine types and a number of subtypes to reflect a combination of demographic factors: level of urbanization, urban and rural population growth, and population density. The typology can be used to devise sets of spatially differentiated measures to carry out a demographic policy and to regulate the sociodemographic evolution of regions." 相似文献
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Larisa A. Savelieva Andrei A. Andreev Raphael Gromig Dmitry A. Subetto Grigory B. Fedorov Volker Wennrich Bernd Wagner Martin Melles 《Boreas: An International Journal of Quaternary Research》2019,48(2):349-360
The new pollen record from the upper 12.75 m of a sediment core obtained in Lake Ladoga documents regional vegetation and climate changes in northwestern Russia over the last 13.9 cal. ka. The Lateglacial chronostratigraphy is based on varve chronology, while the Holocene stratigraphy is based on AMS 14C and OSL dates, supported by comparison with regional pollen records. During the Lateglacial (c. 13.9–11.2 cal. ka BP), the Lake Ladoga region experienced several climatic fluctuations as reflected in vegetation changes. Shrub and grass communities dominated between c. 13.9 and 13.2 cal. ka BP. The increase in Picea pollen at c. 13.2 cal. ka BP probably reflects the appearance of spruce in the southern Ladoga region at the beginning of the Allerød interstadial. After c. 12.6 cal. ka BP, the Younger Dryas cooling caused a significant decrease in spruce and increase in Artemisia with other herbs, indicative of tundra‐ and steppe‐like vegetation. A sharp transition from tundra‐steppe habitats to sparse birch forests characterizes the onset of Holocene warming c. 11.2 cal. ka BP. Pine forests dominated in the region from c. 9.0 to 8.1 cal. ka BP. The most favourable climatic conditions for deciduous broad‐leaved taxa existed between c. 8.1 and 5.5 cal. ka BP. Alder experiences an abrupt increase in the local vegetation c. 7.8 cal. ka BP. The decrease in tree pollen taxa (especially Picea) and the increase in herbs (mainly Poaceae) probably reflect human activity during the last 2.2 cal. ka. Pine forests have dominated the region since that time. Secale and other Cerealia pollen as well as ruderal herbs are permanently recorded since c. 0.8 cal. ka BP. 相似文献
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Doklady Earth Sciences - New results are presented on the features of the deep velocity structure of two of the three main tectonic blocks that make up the Kola region—Murmansk and... 相似文献
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Izvestiya, Atmospheric and Oceanic Physics - The paper considers steric level fluctuations in the northern Atlantic Ocean. We use a method that combines AVISO altimetry and GRACE gravity... 相似文献
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Sukhanova I. N. Flint M. V. Sakharova E. G. Fedorov A. V. Makkaveev P. N. Nedospasov A. A. 《Oceanology》2018,58(6):802-816
Oceanology - Based on the material obtained in the spring–summer season of 2016, the composition and quantitative distribution of phytoplankton in the Ob estuary and over the Kara Sea shelf... 相似文献
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Cuboctahedral diamond monocrystals of physical classification type IIb weighing from 0.1 to 2 carats and with minor faces {110}, {311}, and {511} have been synthesized. The crystals are characterized by various hues of blue and dark blue depending on the amount of B in the system. A characteristic feature of these diamonds is a sectorial structure expressed in a nonuniform color distribution. The following types of metallic inclusions in the crystals have been recognized: faceted isometric, lamellar, and extended inclusions; unfaceted irregular and drop-shaped inclusions; and microinclusions. These inclusions are related to the chemical composition of the metal solvent. 相似文献