Selectivity coefficients and values of maximal adsorption of Cd2+ and Pb2+ by soils

The relationship of the selectivity coefficients and maximal adsorptions of Cd2+ and Pb2+ to the main factors of the composition and properties of soils of different genetic types (pH, content of humus, mud, nonsilicate oxides of Fe, and the CEC) is examined. Significant correlations and regression relationships are established between these factors. The identified principles permit consideration of the spatial inhomogeneity of the composition and properties of soils in equations of isotherms, calculation of the values of the parameters of these equations according to data on the composition and properties of the soils, and a deeper understanding of the principles are mechanisms of ion exchange in soils.