MOBILIZATION OF ALUMINUM IN SOIL COLUMNS EXPOSED TO ACIDS OR SALT-SOLUTIONS

Mobilization of aluminium due to acid precipitation was studied in lab oratory experiments using soil columns. Podzol soils were collected fr om the Janow forest south of Lublin, Poland, a site where field studie s have been performed. The experiments were carried out with synthetic solutions of mineral acids (H2SO4, HNO3) and fertilizer salts ((NH4)2 SO4 and NH4NO3) with concentrations of ionic species in the range 10(- 6) -10(-3) eq/1. In agreement with observations in the field, it was f ound that the greatest amounts of aluminium were mobilized from the il luvial (Bhs) and spodic (Bs) soil horizons. Mobilization of aluminium by HNO3 was in most cases higher than by H2SO4 for the same concentrat ions. The two salt solutions gave similar results; for the most concen trated solutions the mobilization from the B-horizons was between that observed for H2SO4 and HNO3. The acids mobilized greater amounts of A l from the C-horizon.