INDICATORS OF THE ENVIRONMENTAL STATUS OF SOILS POLLUTED BY HEAVY METALS

Chernozem Calcic artificially contaminated with Zn and Pb salts and reclaimed by the addition of chalk and glauconite as ameliorants under pot experimental conditions has been analyzed. The group composition of the metal compounds in the soil have been determined according to an original extraction procedure. The mobility coefficient characterized the changes in the environmental status of the metals under the reclamation conditions have been proposed for describing the formation tendencies of the metal composition in the soils. It is calculated from the analysis of the group composition of the metal compounds. The mobility coefficient characterizes the environmental vulnerability of soils to the impact of HMs. The obtained experimental data characterize the behavior features of Zn and Pb in the studied soil. An increase in the environmental hazard has been revealed at the contamination of soils with HMs, as well as its decrease at the application of the tested ameliorants. The participation of both strongly and loosely bound HM compounds in the development of the HM mobility in the soils to their impact has been shown. The contamination of soils with Zn and Pb is accompanied by the transition from the predominance of strongly bound metal compounds to the domination of their loosely bound forms. It was revealed that the reclaiming effect of chalk and glauconite added separately is ensured by their ability for decreasing the mobility of metals in contaminated soils due to their strong fixation by soil components.