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Goncharuk V.V.,Ukrainian Academy of Sciences | Lapshin V.B.,Ukrainian Academy of Sciences | Chichaeva M.A.,Fedorov Institute of Applied Geophysics State Federal Budgetary Establishment | Matveeva I.S.,Zubov State Oceanographic Institute | And 3 more authors.
Journal of Water Chemistry and Technology | Year: 2012

We have investigated concentration levels of heavy metals, aluminum, and arsenic in the near-water layer of the atmosphere. Heavy metal concentrations in the sea aerosols of the seas of the western part of the Arctic are within the range from 0.01 to 1000 ng/m 3. The data collected in highland regions of the Arctic Ocean are considered as background values: the least levels of concentrations typical of Cd and Pb (~0.01 ng/m 3), the highest ones-of Al, Fe, and Zn (~100 ng/m 3). In the southern part of the Atlantic Ocean the concentration range of the elements being investigated constitutes 0.1 to 1000 ng/m 3. Recurrence of the content of the elements in these regions is determined by natural processes of the matter carry-over and points to the ingress of heavy metals to the aerosol due to its generation by the sea surface. The composition of the aerosol of coastal areas of the Black, Caspian, and Baltic Seas is more varied: the concentration of the elements constitutes 1 to 10 6 ng/m 3. In certain hydrometeorological conditions the concentration of Ni, Fe, and Cr as part of the particles of the aerodisperse phase generated by the sea surface, exceeds the MAC of the air of the working areas of industrial enterprises. The sea aerosol may be a secondary supplier of toxicants to the coastal areas of the seas. © 2012 Allerton Press, Inc.

Savenko A.V.,Moscow State University | Demidenko N.A.,Zubov State Oceanographic Institute | Pokrovskii O.S.,Tomsk State University
Geochemistry International | Year: 2016

Natural observations were analyzed to study the distribution of dissolved species of major and trace elements in the Onega and Mezen’ mouth areas and the tendencies in the chemical transformations of the is continental runoff in the river mouths of the White Sea drainage system. It is shown that the migration of major ions and dissolved species of Li, Rb, Cs, Sr, B, F and Mo is consistent with a conservative behavior and is controlled by hydrodynamic processes. The amounts of uranium and barium additionally supplying in the Mezen’ mouth exceed those removed with a continental runoff, whereas the Onega, Severnaya Dvina, and other rivers of the White Sea drainage system are characterized by the conservative behavior of uranium, while barium desorption from particulate matter reaches no more than 33% of its content in the riverine waters. The growth of concentrations of these elements in the Mezen’ mouth is caused by the long-term interaction of solid matters of the continental runoff with saline waters in the tide-affected estuary. 28–59, 12–63, 25–67 and 20–63% of concentrations of iron, aluminum, lanthanum, and cerium are removed from the riverine waters in the mouth areas of all studied rivers of the White Sea drainage system mainly owing to the coagulation and flocculation of organic and organomineral colloids. The distribution of dissolved species of mineral phosphorus and silicon in the Mezen’ mouth is presumably controlled by the remineralization of the organic matter in the bottom sediments, which due to the hydrological features of estuary are regularly stirred up and interact with vertically mixing water sequence. Up to 20–46% of dissolved phosphates and 3–22% of silicon are removed from the continental runoff during vegetation period in the mouths of the Onega, Severnaya Dvina, and other rivers of the White Sea drainage system mainly owing to their biological consumption. © 2016, Pleiades Publishing, Ltd.

Filippov Y.G.,Zubov State Oceanographic Institute
Russian Meteorology and Hydrology | Year: 2015

Considered are the issues of the impact of the Don River runoff on the water level in the eastern part of the Taganrog Bay as well as the issues of the determination of the real depth in this part of the sea. Investigated are the cases of the wind absence and wind of western and eastern directions. Presented is the forecast of the sea level in the eastern part of the Taganrog Bay. © 2015, Allerton Press, Inc.

Feniova I.Y.,RAS Severtsov Institute of Ecology | Aibulatov D.N.,Moscow State University | Zilitinkevich N.S.,Zubov State Oceanographic Institute
Inland Water Biology | Year: 2013

Simulation modeling was performed to study the impact of individual variability on the population dynamics of particular cladoceran populations and the outcome of interspecific competition at low and high temperatures. The study was performed on one species of small size (Ceriodaphnia quadrangula O.F. Müller) and one species of large size (Simocephalus vetulus O.F. Müller). Laboratory experiments were performed to estimate the average values of principal demographic parameters of these species and their coefficients of variability at two temperatures, 18 and 27°C. Population dynamics of the two species in mono- and mixed cultures was simulated with and without accounting for individual variability using available published data and our own data on demographic parameters. Individual variability was shown to help populations survive unfavorable trophic conditions and to give competitive advantage over populations in which all individuals of the same age are identical. Individual variability decreased with rising temperatures due to probable acceleration of physiological processes. © 2013 Pleiades Publishing, Ltd.

Feniova I.Y.,RAS Severtsov Institute of Ecology | Zilitinkevich N.S.,Zubov State Oceanographic Institute
Russian Journal of Ecology | Year: 2012

Laboratory experiments and computer simulations have been performed to study the influence of increased temperatures on the structure of cladoceran communities. Analysis of changes in the rate of population growth and demographic parameters has shown that smaller cladoceran species are less sensitive to decreased concentrations of food at any of the test temperatures (18, 21, and 27°C). An increase in temperature from 18°C to 27°C has been shown to facilitate the establishment of acute competition conditions. At 18°C, periods of food deficiency are shorter, and competition is therefore less manifested than at 27°C. According to the results of computer simulations, alleviation of competition in waters with "low" temperatures results from reduction of the periods of food deficiency because of prolonged juvenile development. © 2012 Pleiades Publishing, Ltd.

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