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Information × Registration Number 0211U002343, 0106U000133 , R & D reports Title Geochemistry of man-made radionuclides and microelements in natural-antropogeneous ecosystems popup.stage_title Head Bondarenko G.N., Registration Date 03-02-2011 Organization Institute of environment geochemistry popup.description2 By experimental study of the dynamics of ion-exchange and unexchange sorption of 137Cs by sod-podzolic soil and its individual fractions, dynamics of sorption of radionuclides by clays of different mineral composition and dynamics of 137Cs sorption by plageogranit, it was found that radionuclide sorption by soil and rock occurs on several types reaction centers with different rates. It was found that kinetics of exchange and unexchange sorption of 137Cs and 90Sr by all of the studied sorbents is described by Binomial first order kinetic equations for each type of centers. Rate constants of adsorption/desorption and fixation/remobilization of 137Cs and 90Sr for each type of centers were determined. The rate constants of 137Cs fixation by soil at III-type centers were found to be commensurate with the values of 137Cs immobilization rate constants determined earlier by the authors for contaminated soils of the Chernobyl Exclusion Zone. After the five-year study of the speciation of Pb and Zn, artificially introduced in sod-podzolic and chernozem soils of research sites, it was found that the immobilization of Pb and Zn in chernozem soil is more effective than that in sod-podzolic one. Heavy metal imobilization rate was found to depend on soil contamination level. It was found that the rate of vertical migration of heavy metals and their transfer into vegetation are determined by dynamics of Pb and Zn mobile species in the soil. Rate of self-purification of plants decreases with increasing of soil contamination level by heavy metals. In the soils of zones of influence of Trypilia and Burshtyn TP's some elements (Pb, Zn, Cu, Ni, Hg, Mn, Cr) showed the contents, exceeding those of clean soils, heavy metal pollution of soils in the zone of Burshtyn TP being more significant than that in the zone of Trypillia TP. Bulk concentrations of Pb, Zn, Ni, Cu in soils of some studied areas in the zones of Burshtyn and Trypillia TP's exceed MAC, but their mobile species concentrations in soils don't exceed normative values for these pollutants. The theoretical foundation of geochemical prediction and reconstruction of ecological condition of natural-anthropogenic ecosystems, based on the dependence of biogenic and abiogenic flow of pollutants (radionuclides or heavy metals) on the dynamics of their speciation in soil, has been developed. It was shown that the equation of transformation kinetic model describing the dynamics of radionuclide mobile and fixed species in soil, can serve as mathematical tool for geochemical forecasting of radioecological situation. Kinetic constants of radionuclide immobilization in soil can be determined by the results of laboratory model experiments. Product Description popup.authors Бондаренко Максим Германович Висотенко Оксана Олександрівна Власенко Володимир Іванович Демченко Лариса Володимирівна Заборовський Віктор Стефанович Колябіна Ірина Леонідівна Кононенко Людмила Василівна Коромисліченко Таїсія Іванівна Кузенко Світлана Володимирівна Лавров Петро Іванович Маланіч Леонід Климентійович Манічев Вячеслав Йосипович Марініч Ольга Василівна Садолько Ігор Вікторович Сиротенко Георгій Іванович popup.nrat_date 2020-04-02 Close