MODEL STUDY OF ACID-RAIN EFFECT ON ADSORPTION OF TRACE-ELEMENTS ON SOILS USING A MULTITRACER

Using a radioactive multitracer and model acid rain (HCL or H2SO4 solu tion), batch experiments were performed to examine the pH effect on th e adsorption-desorption equilibrium of 16 elements on soils as a model study of an acid rain effect. Kaolin, black soil (original and with o rganic matter almost removed) and Kureha soil (original and with organ ic matter almost removed) were used as adsorbents. Characteristic depe ndence on the pH value of the suspension was observed for the adsorpti on of the elements on kaolin and the soils. The results of this model study indicate that acid rain decreases the retention of cations, whil e it increases or does not change the adsorption of anions on soils. O rganic matter in soils has a positive effect on the extent of adsorpti on of most elements investigated.