Cryoaridic soils were proposed to be identified as an individual genetic soil type by Vladimir Volkovintser in the 1970s. Volkovintser argued that the specific properties of these soils are in good agreement with the soil-forming factors: ultracontinental climate, cryoxerophytic steppe or tundra-steppe vegetation, dry permafrost, and skeletal parent material. In cryoaridic soils, the properties of chestnut and pale soils are combined, but their individual features are due to the specific cryohumus AK horizon and secondary carbonates dominated by pendants. Cryoaridic soils were not included in the soviet soil classification system of 1977; in the Russian soil classification system, the type of cryoaridic soils with the AK–BPL–BCA–Cca horizons is included in the order of pale-metamorphic soils with the pale-metamorphic BPL horizon as diagnostic for all soil types of this order. However, our field research, analysis of publications, and the study of soil in the Central Soil Museum give us grounds to verify diagnostic criteria, to change the profile type formula of cryoaridic soils, and to review their taxonomic position in the classification system. We argue that the BPL diagnostic horizon should be replaced by the diagnostic property (pl), which means that cryoaridic soils should be transferred into another order, presumably, the order of humus carbonate-accumulative soils. Some additional subtypes are proposed. On highly skeletal shallow parent materials, cryohumus soils belonging to the order of organo-accumulative soils are developed.

The article is aimed to assessing the potential for humus accumulation in soils of dry steppes of the Central Tuva and Turan–Uyuk basins of Tuva. The research into organo–mineral interactions as the main mechanism for the stabilization of organic matter and its accumulation in the soil form the methodological basis of this study. The results of assessing the humus accumulation potential of soils in dependence on the physical clay (<0.01 mm) are discussed. It is argued that humus accumulation under specific bioclimatic conditions of the region is limited by the scarce resources of the physical clay fraction. As a result, despite the large volumes of incoming plant residues, the soils are characterized by the low content and pool of humus. It is shown that in chestnut soils (Cambisols) the texture-dependent potential for humus accumulation is not fully realized (less than 100%). In chernozems (Chernozems), this potential is realized to a maximum degree under the existing bioclimatic conditions. The proposed methodological approach makes it possible to take into account the modern processes of soil deflation, estimate the losses of physical clay and humus, and determine the necessary measures for soil fertility recovery, which is very important for the arid region.

The results of assessing the soil-ecological efficiency of reclamation activity on different ages coal dumps in the forest-steppe of Kuzbass are presented. The main physical and chemical soil properties were studied: density, clay fraction and organic carbon in the areas of forestry and agricultural reclamation measures and natural overgrowing. It was revealed that the maximum efficiency achieves by technologies of the fertile layer of natural soils application on the surface of dumps (more over 80% of efficiency).

The results of a study of the specifics of recultivation at mining enterprises of the Republic of Tuva are presented The analysis of the availability bioclimatic and lithological resources necessary for the effective implementation of various directions of reclamation are given. It was revealed that, despite the diversity of natural conditions and landscapes, the region has a clearly expressed deficit of potentially fertile rocks and a fertile soil layer. It is shown that the soil-ecological efficiency of self-restoration, assessed by the nature of the newly formed soil cover and the accumulation of pedogenic organic matter, is low, and the state of self-restoration landscapes is unsatisfactory.

СВЕТЛОГУМУСОВЫЕ АККУМУЛЯТИВНО-КАРБОНАТНЫЕ И ПАЛЕВО-МЕТАМОРФИЧЕСКИЕ ПОЧВЫ КОЛЛЕКЦИИ ЦЕНТРАЛЬНОГО МУЗЕЯ ПОЧВОВЕДЕНИЯ: ВЕРИФИКАЦИЯ ТИПОВОЙ ДИАГНОСТИКИ