Incipient podzolization processes in Humic Acrisols of southern Spain

Soils with morphological evidence of podzolization occur in Sierra Morena (southern Spain). Six soils, identified as Humic Acrisols, were sampled for detailed study. Distribution of oxalate- and EDTA-extractable Al in Fe in the profiles indicated that substantial amounts of both elements had been translocated from the A to the incipient podzolic B horizons. Part of the Al, but almost no Fe, was present as organic complexes, suggesting that these two elements were transported to, or remobilized in the B horizons by different mechanisms. Allophane was present, albeit in small amounts, in two soils. Both inorganic and organic theories of podzolization were able to explain the Fe and Al distribution data.