Edafología. Volumen 7-3. Septiembre 2000. pág 227-239.
The influence of gypsum and lime+gypsum amendments on various extractable forms of Al in two reconstructed acid soils (plinthic Palexerult and arenic pachic Palexerult) was investigated. The addition of gypsum depolymerizes non-hydrolysable C and increased the extraction of Al bound to organic matter in the case of the plinthic Palexerult profile. Excepting the exchangeable Al on the plinthic Palexerult profile, the gypsum amendment increases the proportion of all forms of Al extracted (bound to organic matter, sorbed, oxalate and citrate) with various selected reagents relative to control samples. In general, the amount of Al extracted increases with increase in that of gypsum added.
Key words: Acid soils, gypsum, lime, extractable Al