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Comparative characteristic of several microelements (Ni, Cu, Sr, Al, Zn, Co, Mn, Pb, Cd, Hg, As) found in fish (case study of breams in the Volga basin reservoirs) is presented. Regularities of accumulation of these elements in fish depending on their concentration in the water are analyzed. Main disturbances in fish caused by the accumulation of microelements in their organs and tissues are considered. 相似文献
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Razzhigaeva N. G. Kopoteva T. A. Makarova T. R. Grebennikova T. A. Lyashchevskaya M. S. Mokhova L. M. Ganzey L. A. Kudryavtseva E. P. Panichev A. M. Klimin M. A. Arslanov Kh. A. Maksimov F. E. Petrov A. Yu. 《Doklady Earth Sciences》2023,507(1):S69-S80
Doklady Earth Sciences - Comprehensive study of sections of mares in the Bolshaya Ussurka River basin has allowed highlighting climate changes over the past 2900 years. Reconstructions are based on... 相似文献
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An input–output model was applied to analyze the used freshwater and total used water in Russian economy sectors over 2005–2010. In addition, the sectors that are the main sources of wastewater discharge are identified and the volumes of water sent abroad with exported products are calculated based on data on 2011. The compiled scheme of intersectoral flows and water use in the country can be used as a base for water resources management. 相似文献
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T. I. Moiseenko N. A. Gashkina A. N. Sharov O. I. Vandysh L. P. Kudryavtseva 《Water Resources》2009,36(3):296-309
Transformation of an Arctic aquatic ecosystem (a case study of Lake Imandra) under the impact of a mining industrial complex is considered. Water chemical composition and the ecosystem’s structural components (phyto- and zooplankton, zoobenthos, and ichthiofauna) are analyzed for the following periods: the preindustrial background (reference) conditions, industrial development of mineral resources and strong anthropogenic impact, industrial recession and decreased anthropogenic impact, and stabilization. The main regularities of the aquatic ecosystem successions under the conditions of anthropogenic loads and their decrease are established. 相似文献
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The problem of eutrophication of the surface water in the Arctic Regions is discussed. The natural hydrochemical indices of the trophic status of lakes are analyzed in connection with the landscape and physiographic features of the Kola Peninsula. The regular features of changes in the hydrochemical indices of the trophic status of lakes and the development of the process of eutrophication are analyzed in the case of subarctic Lake Imandra, which has been polluted with municipal and industrial (phosphorus-containing waste of the apatite production) wastewater for more than fifty years. Criteria are proposed for establishing and assessing water eutrophication in cold climate. 相似文献
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Variations in the key indices of the chemical composition of surface waters are studied in a region where these waters are polluted by mining plant wastes. The forms of metals migration and their distribution in the bottom deposits of watercourses are examined. The possible steps for reducing the pollution of water in a watercourse are discussed. 相似文献
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Shan-Jie Qian N. A. Kudryavtseva S. Britzen T. E Krichbaum Long Gao A. Witzel J. A. Zensus M. E Aller H. D. Aller Xi-Zhen Zhang 《中国天文和天体物理学报》2007,7(3):364-374
During the period 1966.5–2006.2 the 15GHz and 8GHz light curves of 3C 454.3 (z = 0.859) show a quasi-periodicity of ～12.8 yr (～6.9 yr in the rest frame of the source) with a double-bump structure. This periodic behaviour is interpreted in terms of a rotating double-jet model in which the two jets are created from the black holes of a binary system and rotating with the period of the orbital motion. The periodic variations in the radio fluxes of 3C 454.3 are suggested to be mainly due to the lighthouse effects (or the variation in Doppler boosting) of the precessing jets caused by the orbital motion. In addition, variations in the rate of mass accreting onto the black holes may be also involved. 相似文献
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Novichkova E. A. Reykhard L. E. Belyaev N. A. Aliev R. A. Starodymova D. P. Kudryavtseva E. A. 《Oceanology》2020,60(5):664-681
Oceanology - The lithological and mineralogical characteristics of sea surface sediments, composition of microfossils, contribution of organic matter, and element composition have been studied in a... 相似文献
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The values and seasonal variations of the primary production and chlorophyll a content were investigated in the Russian sector of the Southeastern Baltic in 2003–2007. The annual average values of the
primary production and chlorophyll content for this area were 231 gC m−2 year−1 and 2.9 mg/m3, respectively; i.e., they corresponded to the mesotrophic level according to the trophic classification. The spatial distribution
of the primary production and the chlorophyll concentrations in the different seasons and the annual average increased values
exhibited at the northern coast of the Sambian Peninsula and the Curonian Spit were determined. In these areas, the values
of the primary production and the chlorophyll concentrations corresponded to the eutrophic level. 相似文献