The possible significance of poly‐phenols in soil formation

Abstract

Abstract Soils of the podzol group are characterized by the translocation of iron compounds down the profile; it is considered that the ferric oxide in the uppermost horizons of the soil is mobilized by the action of soluble organic compounds leached from the overlying tree litter. The solution and reduction of ferric oxide by aqueous leaf extracts is apparently caused by the joint action of carboxylic acids and polyphenols. The development of a horizon of clay accumulation is a feature of certain podzolic soils. As aqueous leaf extracts have the property of dispersing clay suspensions, it is apparent that the development of textural profiles could be promoted by the action of these extracts. In the dispersion of clays, polyphenolic compounds constitute one of the chief groups of active compounds.