Irina Olegovna Alyabina

Approaches used to assess the diversity of soils in Russia as well as algorithms of quantitative assessment of the differentiation of soil bodies and soil mantles are described. To assess soil diversity (or the degree of differentiation of materials from parent rocks into soil bodies and soil covers) two indices were introduced: index of vertical differentiation — Ird; index of spatial lateral differentiation — Ild (red). These indices were computed according to the structure of the soil cover on the Soil Map of the Russian Federation on a scale of 1 : 2.5 M within the spatial framework of the Map of Soil-Ecological Zoning of the Russian Federation on a scale of 1: 2.5 M. The most complex soil cover and soil profiles on plains were found for the zones of Soddy-podzolic soils (Umbric Albeluvisols/Umbric Podzols2) of southern taiga and Grey forest soils (Albic Luvisols/Luvic Greyic Phaeozems) of deciduous forests (they locate on the boundary of Boreal and Subboreal geographic belts and are characterized by wide spreading of dynamic-mature soils), as well as in mountains — for soil provinces in the Caucasus. Key words: pedodiversity, indices of differentiation, vertical differentiation of soils, lateral spatial differentiation of soil cover.

The properties of representative soil profiles of podzols included in the database of the Unified State Register of Soil Resources of Russia are considered. As a result of processing and analysis of the data array (53 measured profiles), the ranges of values of a number of parameters were adjusted. It was found that in most cases the properties of podzols had a wider range of values compared with the estimated profiles given in the literature (thickness of illuvial horizon, humus content in eluvial horizon), at the same time, the range of values of the humus content for the illuvial horizon was narrower. The specificity of the podzols of individual regions obtained by combining of soil provinces of the Map of soil-ecological zoning is revealed. Regularities can be traced in the geography of the profile thickness of these soils, the content of humus and its profile distribution. In Siberian regions humus prevails in the eluvial soil horizon, in the European territory of the country and in Primorye - in the illuvial horizon.