EFFECTS OF SIMULATED ACID-RAIN ON THE DYNAMICS OF ALUMINUM IN AN ACID FOREST SOIL .1. MOBILITY OF ALUMINUM IN MORE READILY AVAILABLE FORMS FOR PLANTS

The effects of simulated acid rain on the different forms of aluminium most readily available for vegetables (exchangeable aluminium, chelated aluminium by organic substance, active aluminium) were evaluated. In fact, toxicity from aluminium is the main factor in decay of vegetables in highly acidic soil. A highly unsaturated acid soil (pH 4.3 in water) was used to reveal in a short time (6 months of treatment) phenomena that in nature require longer periods. An increase in the different forms of aluminium was observed with increasing acidity. The differences were statistically significant and although slight with respect to the quantities of extracted aluminium, were sufficient to cause toxic phenomena in the vegetables. The studied soil should be considered potentially susceptible to aluminium toxicity for the vegetables.