STUDIES OF THE EFFECT OF SIMULATED ACID-RAIN ON THE ECOLOGICAL EQUILIBRIUM OF THE SOIL SYSTEM .3. SOME ELEMENTS OF SOIL CHEMISTRY CHARACTERISTICS IN THE EXPERIMENT WITH ACID-RAIN SIMULATION

A six-year field experiment involving diluted sulphuric acid treatment of a sandy soil maintained as bare fallow was carried out. Irrespecti ve of the experimental variant (0, 0.5, 1.3, and 1.8 acid equivalents per m(2) per year), neither accumulation of sulphate nor other pronoun ced changes in the chemical composition of the soil were observed, whe reas the saturation degree of the cation exchange capacity (5.6 meg/10 0 g soil in the control) decreased in the surface layer from ca. 65-13 %, respectively. After half of plots were sown with grass, the soil un der grass contained more mineral nitrogen compounds and less organic n itrogen, compared to bare fallow, irrespective of the soil treatment.