Heavy metal and aluminium mobilization in soils from Galicia (NW spain) as a consequence of experimental acidification

In this paper the main results of an experimental acidification of 5 Galician soils are presented. The acid input caused decrease in pH and mobilization of Al and some heavy metals. Owing to the great differences in the soils studied, the type of metal released and its concentrations in solution varied greatly. pH and metal content of the soils were the factors most influencing metal mobilization. The acid input greatly enhanced the mobilization of Al in the most acidic soils, particularly those developed from mica schist or shale. Large increases in Mn were observed in the soils developed from serpentinite and mica schist. The greatest Zn increase took place in soils derived from granulite and shale. Nickel increased only in the soil developed on serpentinite. Mobilization of Cu and Pb did not occur in any soil.