Soddy-Podzolic Soils with a Complex Organic Profile in the Right-Bank Part of the Lower Vyatka River Basin

Data on soddy-podzolic soils with the second humus horizon in the southwestern part of Kirov oblast are discussed. These soils were first studied by the authors on mantle calcareous loams of the Yarano- Kokshagskaya Plain in the eastern part of the Central Russian southern-taiga province of medium-humus soddy-podzolic soils of European Russia. The aim of this study is to reconstruct the history of the development of soil properties and soil cover in automorphic landscapes of this region. Morphology, substantive properties of mineral and organic components, soil genesis and evolution are analyzed using a set of physical, chemical, physicochemical, biochemical, and geochronological methods. The results of our study attest to the relict character of second the humus horizon and polygenetic nature of the studied soils. These soils have passed through two essentially different evolutionary stages in the Holocene: the accumulative stage in the first half of the Holocene and the accumulative-eluvial stage of erasing evolution with preservation of some inherited features in the second half of the Holocene. According to their properties, the studied soils are analogous to the earlier studied southern-taiga Vyatka–Kama province of high-humus soddy-podzolic soils of the northeast. At present, plowing of these soils leads to a partial or complete destruction of the second humus horizon; thus, spontaneous degradation processes are complemented by the human-induced soil degradation. A tendency for a gradual disappearance of these soils from the soil cover under the influence of natural and anthropogenic factors has been noted. The materials presented in this paper may be useful for organization of specially protected soil areas in the southwestern part of the Vyatka River basin.