Mathematical models of regional standards of the Soil District (39) of leached heavy medium-thick chernozems of the rolling steeply-sloping foothills of the Altai Region

Abstract

This study is the continuation of the development of the regional soil classification of the Altai Region. The profile and genetic soils classification of the USSR (1977) was used as the basic classification. Information-logical analysis was used to substantiate the classification boundaries of the soil taxonomic groups of the 39th soil district. The studied area is the rolling steeply-sloping foothills of the Altai Region with predominant leached heavy medium-thick chernozems. The soil cover also contains gray and dark gray forest soils, meadow-chernozem and chernozem-meadow, and meadow soils. The taxonomic weight of diagnostic features for the soils of the 39th soil district has been determined. These features reflect the intensity of the main (sod pedogenesis) soil-forming process in the soils. The following features have the maximum taxonomic weight: pH_H2O, humus content, and total absorbed bases. The classification boundaries of the main soil types and subtypes of the 39th soil district are determined on the basis of the specific (most probable) conditions. The analysis of the regularities of property changes in the soil profile in quantitative models of regional soil standards reflect the development of agrogenic processes in the soils as water erosion and agricultural depletion regarding nutrients and absorbed cations. Qualitative and quantitative models of regional soil standards allow identifying real soil belonging to a certain taxonomic group by a set of physico-chemical, morphological and physical properties. Mathematical models of regional soil standards allow determining the trends of modern soil forming processes, quantifying them and justifying long-term development forecasts. The obtained models may be used as quantitative criteria for monitoring of the ecological state of soils and evaluating the degree of degradation processes in the soil under present-day conditions.