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Iskra AA Palitskaya TA Pechkurov AV Popov VK 《Journal of environmental radioactivity》2004,72(1-2):89-95
The evolution of the Russian Federation legislation and regulation concerning the radiation protection of the population, the environment and the monitoring is presented. The main federal laws--"On the Environmental Protection", "On the Atomic Energy Use", "On the Radiation Safety of Population", etc. as well as standards of radiation safety, sanitary and hygienic norms, international agreements and conventions are briefly summarized. Main directions towards further improvement of the environmental radioprotection regulation in Russia are pointed out. 相似文献
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P. P. Popov 《Russian Journal of Ecology》2003,34(1):27-33
The structures and differentiation patterns of the Norway spruce (Picea abies) and Siberian spruce (P. obovata) populations have been studied in a wide area, including the transition zone of their continuous geographic range. The areas occupied by transitional populations have been detected. Series of distinct populations of the Norway and Siberian spruces are located to the west and east of them, respectively. 相似文献
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Data on the parameters of migration of two land snails of the genus Xeropicta are presented. In relatively homogeneous habitats, the locomotor activity of these mollusks is relatively high: they can travel for up to 300 cm per day, with neither the phenotype nor size of the shell having any significant influence on the level of dispersal. The snails prefer to travel westward and southward, but the distances covered by individuals moving in different directions are similar. No connection between the directions or distances of movement on two successive days has been observed. 相似文献
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Mario Mitov Elitsa Hristova Georgi Hristov Rashko Rashkov Marina Arnaudova Alexander Popov 《Environmental Chemistry Letters》2009,7(3):249-253
NiW systems are known as one of the best catalysts for various desulfurization processes. In this study, we examined catalytic
properties of NiW electrodeposits, produced from two different electrolytes, towards sulfide ion oxidation in alkaline solution.
Despite the big difference in morphology and structure of both materials, they exhibit almost the same catalytic activity
for the examined reaction. A possible explanation of this experimental fact is that the overall reaction is controlled by
the transport of oxygen through the catalyst samples. 相似文献
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Dorothe Ehrich Niels M. Schmidt Gilles Gauthier Ray Alisauskas Anders Angerbjrn Karin Clark Frauke Ecke Nina E. Eide Erik Framstad Jay Frandsen Alastair Franke Olivier Gilg Marie-Andre Giroux Heikki Henttonen Birger Hrnfeldt Rolf A. Ims Gennadiy D. Kataev Sergey P. Kharitonov Siw T. Killengreen Charles J. Krebs Richard B. Lanctot Nicolas Lecomte Irina E. Menyushina Douglas W. Morris Guy Morrisson Lauri Oksanen Tarja Oksanen Johan Olofsson Ivan G. Pokrovsky Igor Yu. Popov Donald Reid James D. Roth Sarah T. Saalfeld Gustaf Samelius Benoit Sittler Sergey M. Sleptsov Paul A. Smith Aleksandr A. Sokolov Natalya A. Sokolova Mikhail Y. Soloviev Diana V. Solovyeva 《Ambio》2020,49(3):786-800
Lemmings are a key component of tundra food webs and changes in their dynamics can affect the whole ecosystem. We present a comprehensive overview of lemming monitoring and research activities, and assess recent trends in lemming abundance across the circumpolar Arctic. Since 2000, lemmings have been monitored at 49 sites of which 38 are still active. The sites were not evenly distributed with notably Russia and high Arctic Canada underrepresented. Abundance was monitored at all sites, but methods and levels of precision varied greatly. Other important attributes such as health, genetic diversity and potential drivers of population change, were often not monitored. There was no evidence that lemming populations were decreasing in general, although a negative trend was detected for low arctic populations sympatric with voles. To keep the pace of arctic change, we recommend maintaining long-term programmes while harmonizing methods, improving spatial coverage and integrating an ecosystem perspective. 相似文献
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P. P. Popov 《Russian Journal of Ecology》2010,41(5):378-385
Discriminant analysis has been used to analyze the composition of phenotypic forms and geographic differentiation of spruce
populations in northwestern Russia in comparison with those of “standard” Norway spruce and Siberian spruce populations. The
absolute prevalence of trees with an intermediate Norway-Siberian spruce phenotype has been revealed in almost all populations,
except for the northernmost ones. Spruce populations in northwestern Russia may be divided into at least three groups, with
the southern group being closer to the Norway spruce, and all other groups, to the Siberian spruce. 相似文献
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P. P. Popov 《Russian Journal of Ecology》2012,43(1):13-18
Reference populations identified within the continuous range of Norway (Picea abies) and Siberian (P. obovata) spuces significantly differ in biometric characters of seed scales, relative position in the same coordinate system (Root
1 and Root 2), phenotypic structure, and mutual taxonomic position (according to the squared Mahalanobis distance). Due to
the symmetrically equal positions of the populations relative to each other, they can be used as reference populations in
discriminant analysis at a two-, three- or five-class gradation of the test character. 相似文献
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P. P. Popov 《Russian Journal of Ecology》2017,48(5):403-408
Structure and diversity of populations in the European and Siberian spruces were studied by their phenotypes. On vast areas of their total range in the east of Europe and Siberia, significant variability of intrapopulation diversity index in the frequency of individual phenotypes is observed. All analyzed populations are divided into two large groups: with low (and decreased) and high (and increased) levels of intrapopulation diversity. A high level of diversity was observed in the regions with hybrid or intermediate populations, while a low level was in the regions with populations of European and Siberian spruces without genetic interference. Mean level of diversity is typical for the areas with populations transient in these characters. 相似文献
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