New soil hydromorphism index based on state of iron

Abstract

A new soil hydromorphism criterion based on a sequential iron extraction scheme is proposed. This criterion agrees with the color of the forest soils of the cis-Ural region better than the Schwertmann criterion. A soil hydromorphism gradation scale is given on the basis of the hydromorphism criterion, according to which hydromorphism is absent or expressed weakly in forest soils on eluvium and deluvium of Upper Permian deposits. In alluvial soils it is expressed not only to a weak but also to a moderate degree.