Interaction between metal ions in waters with humic acids in gley-podzolic soils

The paper addresses complexation of metal ions with humic matter in soils. The functional specifics of humic matter extracted from gley-podzolic soils are estimated using spectrometric techniques. Conditional stability constants are experimentally determined for Fe(III), Cu(II), Pb(II), Cd(II), Zn(II), Ni(II), Co(II), Mn(II), Cr(III), Ca(II), Mg(II), Sr(II), and Al(III). The activities of metals are ranked according to their affinity to humic compounds in soils. The determined conditional stability constants of the complexes are tested in model experiments, and it is demonstrated that Fe and Al ions have higher conditional stability constants than ions of alkali-earth metals, Pb, Cu, and Zn.