Diagnostic criteria for elementary soil-forming processes in profile-differentiated soils of the Precarpathian region

Abstract

The genesis of profile-differentiated soils of the Precarpathian region is the most debatable process because of the different diagnostic features that are used to determine the elementary soil process (ESP). The aim of the study is to establish a set of morphological, chemical and physico-chemical diagnostic features of soil-forming processes based on the analysis of soil morphology and neoplasms, gross chemical composition of fine earth, silt and soil tumors (nodules, hardpans and cutans). Methods of research: profile, comparative-geographical, laboratory-analytical. The object of the study: profile-differentiated soils (sod-podzolic and brown-podzolic soils) of the Precarpathian region. It was established that the main ESPs that form the genetic profile of profiled-differentiated soils is lessivage, podsolization, internal soil argillization, gley-elluviation and segregation. These research was based on own field and laboratory-analytical studies. In sodpodzolic soils major profile forming of ESP is podsolization , characterized by negative values of the elluvial-accumulative coefficients and the coefficients of silica changes for the upper horizons, presence of skeletans and seskvans and gley-elluvial which is diagnosed by a significant predominance losses of Fe2O3 over Al2O3 and as well as with the presence of hardpans. The processes of lessivage and segregation have little intensity. The main profile forming of the ESP in brownsoil-podzolic soils are lesyvazh and internal soil argillization with little action of podsolization and gley-elluviation. On a dominant effect of lessivage in brownsoil-podzolic soils indicate argillans (clay cutans). Their particle size distribution is heavier compared to that which is contained in the horizon and flat within the profile relations SiO2 : R2O3 and SiO2 : Al2O3 in silty fractions .The process of internal soil argillizationin brownsoil-podzolic soils characterize the positive balance of oxides of silt fraction, the nodules presence within the whole profile, rate of change of silica in the silt fraction of more than 1.0, the rate of accumulation of Mn3O4 in noduls and argillans more than 1.0. Introduction of united diagnostic features for profile-differentiated soils of the Pre-Carpathian region will solve genetic and classification problems.