The basic three-component classification system of soils of the world was published by V.M. Fridland in 1982, and its profile-genetic component was taken as a basis for the classification of soils of Russia (1997– 2004–2008). Unlike the former systems, in that of Fridland the priority is given to soil properties, and this conceptual background is transferred into the new Russian system. The substantive-genetic principles of both systems are implemented in diagnostic horizons and genetic properties; both systems have similar hierarchy of taxa, nomenclature, keys. Changes introduced in the classification of soils of Russia derive either of proposals forwarded in the course of its application, or of information accumulated. They concern the improvement of definitions and introduction of new diagnostic elements; however, the main principles are preserved in the existing and forthcoming versions.  

The Soil Map of the Russian Federation, 1 : 2.5 M scale (1988) requires updating to include soil data that have been accumulated in the past decades, reflect real changes in the soil cover, including anthropogenic transformation, and ensure precise localization of soil objects and correspondence of the map to satellite data with the use of digital soil mapping technologies. The substantive-genetic classification system of Russian soils (2004, 2008) provides the conceptual basis for this updating. The conversion of soil information from the initial map of 1988 into the new classification system is being performed for each polygon of the digitized map. It is based on the analysis of a vast body of diverse information and includes both the search for analogues of the names of mapping units in the new classification system (renaming of the soils) and the correction of the composition of soils in the polygons: new natural soils, cultivated soils (agrosoils), and urban soils are added to the attribute database. The largest number of new natural soils has appeared in legend sections “Soils of tundra” and “Soils of taiga and broadleaved forests”. Anthropogenic soils (119 legend units) that are shown on the map for the first time, have their maximum representation (36 units) in the section “Soils of steppes”; it is close to the number of natural soils (37 units) in this zone. A considerable percent of anthropogenic soils (> 50% of the natural soils) is also typical of legend sections “Soils of broadleaved forests and forest-steppes,” “Soils of dry steppes and semideserts,” “Salt-affected and solonetzic soils”. The total number of natural and anthropogenic soil units (425) in the new legend is more than twice as large as the initial number of natural soil units in the base map (205). The results of the renaming and updating of soils for each soil polygon are fixed in a separate section of the attribute database to the map and will be used for generating the new map by the methods of digital soil mapping.

The relevance of polar research is constantly increasing due to the higher response of Arctic and Antarctic ecosystems to global climate warming compared to other areas of the planet. The increase in average annual temperatures leads to the melting of glaciers, inundation of a part of the territory and, consequently, to the expansion of areas of subaqual (underwater) precipitation. In recent years, there has been a significant increase in the number of studies in which underwater soils are not only recognized as objects of soil science, but are also considered as full-fledged components of the soil cover of the planet. The sustainable existence of soils and ecosystems in Antarctica becomes possible only in local erosion bases – lakes, where biota is oftenly represented only by microorganisms. Biota activity results in the transformation of geological rocks in situ and accumulation of significant organic matter stock. Microbiome seems to be a determining factor of soil formation, namely in subaqueous Antarctic biotopes, which are characterized by all the elementary processes of soil formation in reducing and, often, anaerobic conditions. Nevertheless, quantitative parameters of their microbiome (biomass, cell counts, number of ribosomal genes of prokaryotes and fungi, basal respiration) are still unknown for subaqual soils of Antarctica, although these parameters are necessary for evaluation of ecosystem productivity, including the intensity of the C cycle and biological activity of soil. This review examines the current state of research on microbial communities in Antarctic biotopes, discusses the role of microorganisms in soil formation processes of subaqual soils in Antarctica, and explains the need for microbiological studies of this soil type.

The aim of the article is to submit data about ground water table and soil salinity of the rice irrigated systems at the Sivash seashore in Nyzhnegorsky district of Crimea in 2017–2018 which is 4–5 years from irrigation cease. It was found that many soil cover patterns with salt-affected solonetz at the rice system were leached from salts to the depth about 3–3.5 m by flooding irrigation during half a century. In 2017–2018 ground water tables were deeper than the critical depth. Ground water mineralization is characterized by mosaic spatial distribution, varying from 1.9 to 7.4 g/l with a tendency to growth as ground water depth increases. Depression funnel of ground water table was formed at the seashore. The bottom water drive is up to 0.8–1.6 m relatively sea level. The first symptoms of the salinity returning in grounds of vadose zone were found: (1) appearance of calcium and magnesium chlorides in pore solutions of formally no saline or weakly saline horizons; (2) increasing trend of sodium and chloride ion activity measured in pastes with moisture 50% (w) at the dynamic plots in 2018 as compared with 2017; (3) frequency of grounds with clustered gypsum crystals is increased.

New definitions of “soil carbon sequestration” and “soil carbon deposition” on a quantitative basis taking into account the period of the complete turnover of accumulated organic matter and its distribution over the soil profile are formulated. The carbon protection capacity of soils in the European part of Russia was determined according to Hassink (1997) and Six et al. (2002) based on data of the fine fractions content and the mineralogical composition of soils. The carbon saturation degree of soils and their carbon sequestration potential were calculated according to Meyer et al. (2017) and Wiesmeier et al. (2014). Gray forest and chestnut soils were classified as poorly saturated with organic carbon, meadow slitized and floodplain meadow soils were moderately saturated, and chernozems was saturated. It has been shown that the carbon sequestration potential of gray forest soil is about 30 t C ha^-1, chestnut soil does not exceed 25 t C ha^-1, meadow soil is 15–20 t C ha^-1, and chernozem is less than 5 t C ha^-1. Critical remarks to the 4 ppm initiativewere given.

A comparative assessment of the morphological properties of typical and ordinary chernozems using traditional technology of field crops cultivation with soil treatment and no-till revealed trends in morphological properties changing over time and space. After using no-till on typical chernozems of the Kursk region for 4 years, there was a tendency to increase in humus horizons A and A + AB thickness and in the level of carbonate detection line (10% HCl reaction), which uprose closer to the soil surface. In ordinary chernozems of Stavropol after 7 years of using no-till, this trend is typical only of A + AB horizon. When plowing chernozems, there is a trend to deeper carbonate accumulation level. The gradual accumulation and decomposition of crop residues on the soil surface, which play an important role in wind erosion protection, and less intensive evaporation over time leads to an increase in the thickness of humus horizons and the content of organic matter. The results obtained are indicative of the initialization of morphological properties transformation in chernozems when no-till is used. The decrease in the thickness of the humus horizon on arable lands in Stavropol region results from deflation caused by both numerous soil treatments and a specific wind regime, and direct sowing has demonstrated positive results in the fight against wind erosion processes. When no-till technology is used, chernozems acquire natural features typical of them – variability of properties, i. e. the initial heterogeneity of soil cover, which determines the sustainability of soils in natural ecosystem.

Delineation of especially valuable agricultural lands (EVAL) is currently an important task, which will make it possible to preserve agricultural land for its direct use. There are currently no uniform approaches for delineation of EVAL, or they need to be upgraded. We have proposed a new approach based on GIS modeling and simulation of agricultural plant growth. It is proposed to delineate EVAL for each municipal district taking into account its existing specialization in agricultural production. The allocation of EVAL should be based on the assessment of potential productivity of soils and lands for cultivation of the main crops in the district. EVAL should also include pilot fields and areas used for scientific and educational purposes, regardless of potential soil productivity. The proposed approach has been successfully tested on the example of Yasnogorsk district of Tula region. It is shown that the EVAL map, based on the proposed approach, is more related to the actual land productivity and does not depend on the current land use within the area. It is possible to build an EVAL map for the whole country only by building such maps separately for all municipal districts of Russia.

The most common inaccuracies and errors in the application of statistical methods found in Russian publications on soil science are considered. When designating random variables and distribution parameters in Greek letters, it is necessary to designate those that refer to general populations, and Latin letters – to sampling ones. A detailed description of the experiment and what the replications relate to allows you to draw correct conclusions from the study. It is necessary to avoid pseudoreplication when results at closely located sampling points are considered as characteristics of soil variability over large distances. Expanding the list of descriptive statistics will allow you to use a specific study in meta-analysis. Calculating the confidence interval for the average using the Student's test at different significance levels expands the scope of possible values of the average, but this approach is justified only if the indicator does not differ too much from the normal distribution. When testing statistical hypotheses, it is necessary to pay attention not only to the level of significance, but also to the power of the criterion. The normality distribution hypothesis can be tested using various criteria. The success of applying the criterion depends not only on the validity of the null hypothesis (a truly normal distribution), but also on other reasons: on the sample size and on the alternatives for which the criterion tests the hypothesis. Any statement about the type of relationship between features based on the correlation coefficient (Pearson or Spearman) is meaningless without specifying the number of replicates, since it is the number of replicates that determines the significance of the difference between the correlation coefficient and zero. It is proposed that authors and reviewers pay closer attention to such errors.