Indicators for pedogeochemical barriers of heavy metals’ migration

The aims of this study were to substantiate indicators for pedogeochemical barriers of heavy metals’s migration. The concept of pedogeochemical barriers of heavy metals’migration. Pedogeochemical migration barrier is part of the soil horizon or soil profile, where, as a result of special pedosubstantsiya availability and certain pedogeochemical reactions percolation, there is a significant accumulation of some chemical elements. These barriers act as a «substation-reactionary phenomenon». Pedogeochemical migration barrier grouped into five types: mechanical A, physical (sorption) B, physicochemical (ion exchange) C, chemical D and biological E. Indicators of geochemical migration barriers. To assess the geochemical barriers to migration, A. I. Perelman suggested using barrier contrast indicators and the barrier gradient. Wherein, the barrier contrast is calculated as the ratio of the chemical element concentration on the barrier to its quantity up to the barrier. Barrier gradient is the ratio of soil differences before and after the barrier to its length. Indicators of pedogeochemical migration barriers. In soil science, as the analogue of the barrier contrast are: the contrast ratio, the coefficient of intra-profile differentiation, alluvial-accumulative coefficients. As an analogue of the gradient barriers, there are indices of absolute and relative gradients of pedogeochemical migration barriers. Indicators of Pedogeochemical migration barriers manifest that in the chernozems of ordinary and southern at Kryvyi Rih areas, the accumulation of heavy metals in the humus transition and humus accumulation horizons has been revealed. Wherein, the more intensive action of soil migration barriers is naturally revealed in chernozems of ordinary, in comparison with chernozems southern.