EFFECTS OF SIMULATED ACID-RAIN ON THE DYN AMICS OF ALUMINUM IN AN ACID FOREST SOIL .1. MOBILITY OF ALUMINUM IN MORE READILY AVAILABLE FORMSFOR PLANTS

The effects of simulated acid rain on the different forms of aluminium most readily available for vegetables (exchangeable aluminium, chelat ed aluminium by organic substance, active aluminium) were evaluated. I n fact, toxicity from aluminium is the main factor in decay of vegetab les in highly acidic soil. A highly unsaturated acid soil (pH 4.3 in w ater) was used to reveal in a short time (6 months of treatment) pheno mena that in nature require longer periods. An increase in the differe nt forms of aluminium was observed with increasing acidity. The differ ences were statistically significant and although slight with respect to the quantities of extracted aluminium, were sufficient to cause tox ic phenomena in the vegetables. The studied soil should be considered potentially susceptible to aluminium toxicity for the vegetables.