Парагенетические ассоциации химических элементов в ландшафтах

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The paper discusses the basin, soil and biogeochemical paragenetic associations of landscapes. «Cationophilic» and «anionophilic» components and subsystems of landscapes, specializing in accumulation, depletion or the presence of correlations of chemical elements, are identified. The landscape-geochemical studies of ancient weathering crusts, Paleogene, Neogene and Pleistocene continental deposits, soilgeochemical catenas and plants in various regions of Kazakhstan, Central Asia, the Caspian Sea region and the rivers of the Baikal Lake catchment are synthesized. There are three paragenetic associations of chemical elements in aquatic landscapes of a heterolithic river basin. The first prevalently includes cationic metals – Fe, Mn, Pb and some lithophilic complexing agents (hydrolyzate elements) – Al, Bi, W, Be, migrating in water mainly in suspended forms. The second includes anionic heavy metalloids – Mo, U, Sb, As, as well as light metalloid B, which are presented mainly in dissolved forms. The third association includes chalcophilic heavy metals Zn, Cd, Cu, and also Sn, the fractionation of which is more dependent on hydroclimatic variability, weather conditions and seasonal variations of water flow and turbidity, as well as on the landscape-geochemical conditions of catchments.