The analysis of the practice for regulating the use of dumps of soils and subsoils in the Russian Federation is carried out. It is shown that the existing regulations do not meet modern requirements for the protection and rational use of dumps of soils and subsoils. The absence of a unified recycling approach has been revealed. In some regulatory documents, dumps of soils and subsoils are considered as material for the reclamation of disturbed lands, in others – as industrial waste. Disagreement with the practice of classifying all dumps of soils and subsoils as waste of hazard classes 3–5 and subject to export to special polygons is justified. Disposal of such waste materials is administratively or criminally punishable. This approach to the material of soil excavation causes great harm to both the economy and the environment as a whole. It is proposed to change the practice of irrational use of soil and subsoil dump material and make appropriate changes to regulatory documents. One of such changes may be the introduction of the gradation “environmentally safe waste” into the documents on the definition of the hazard class of waste, with the prescription for the use of soil and subsoil dumps belonging to this category without restrictions on use in the national economy. It is proposed to clarify the magnitude of the soil thickness (soil layer) of 5 m, including the maximum depth of occurrence of fertile soil layer and potentially fertile layer. This value corresponds to the accepted stratigraphic rule on the general regularity of the structure of the sedimentary shell of the Earth. According to this point of view, soils are underlain by subsurface geological rocks, which does not imply the presence of intermediate geological layers between soils and subsurface.

The purpose of the work was to study the concentration of various forms of mineral nitrogen and nitrogen cycle enzymes in farmland soils. The objectives of the research included studying the content of ammonium and nitrate forms of nitrogen, as well as the activity of urease and nitrate reductase in soils of farmland on the territory of the Donetsk People's Republic (DPR). To study the soils of agricultural lands, model sites located in the southern part of the Shakhtersky district of the DPR were selected and represented by moderately washed-out chernozems with low, low and medium humus. The control was an area with steppe vegetation (ordinary chernozem, thick, with medium humus content). The results of the researches allow us to draw conclusions about the development of degradation processes in a number of model sites and their impact on the content of ammonium and nitrate nitrogen in agricultural soils. Growing crops removing substantial amount of mineral nutrients, the slope of the sites surface, and the duration of cultivation of grain crops in the same sites lead to a significant decrease in the concentration of ammonium and nitrate nitrogen. Thus, the most significant decrease in the concentration of nitrogen of ammonium compounds (by 77–82%) was recorded in model slope areas under maize and sunflower. Analysis of the data showed that exchange ammonium is confined to the underlying genetic horizons. The minimum concentration of nitrates in the arable horizon was recorded under the joint influence of such unfavorable factors as: unreasonable layout of fields along the relief elements; violation of crop rotation conditions; use of precursor crops with a significant level of removal of nutrients (wheat, maize). When studying the activity of urease, it was found that a low number of soil microorganisms associated with the cultivation of maize and sunflower, as well as with the development of degradation processes of various genesis, led to the suppression of the functioning of the urease of soils in model areas. The maximum urease activity was observed in areas under winter wheat and amounted to 68–72% in relation to the control indicators. As a result of studies of nitrate reductase activity, a decrease in its values was also found in areas used to grow crops that form a large phytomass (maize and sunflower).

Different laboratory methods of soil quality assessment are considered by the example of soils of the North-Pre-Caucasian province. The article presents a detailed protocol for quantitative determination of Permanganate oxidizable carbon (POXC) fraction using 0.2 M potassium permanganate solution. The data are presented for chernozem type soils of Rostov region belonging to different agroecological groups. Samples of ordinary chernozems (Haplic Chernozems) and meadow-chernozems (Gleyic Chernozems) soils of agrolandscapes were used. Data from non-tilled plots were used to estimate background parameters. Correlation POXC with fraction of bichromate-oxidizable carbon, light fraction (LF< 1.6 g/cm³ ) and waterhydrolysable fractions were estimated. It was found that the content of POXC fraction varied in the range of 126–1 006 mg/kg, with maximum values, on average 925 mg/kg, in samples of humus horizons of ordinary chernozems of plakorny agroecological group of untreated plots. The minimum content of POXC fraction was characteristic for samples of AB horizons of arable plakorny and arable low- and medium eroded agroecological soil groups, on average 218 and 137 mg/kg, respectively. POXC has significant correlations with the fraction of bichromate-oxidizable carbon, the content of light fraction, the content of total nitrogen and soil density, and has shown to be a good marker of agro-ecological conditions on the studied set of samples.

The quality of arable soils largely determines the productivity of agricultural crops and the economic efficiency of their cultivation. The purpose of this work is to analyze the relationship between intra-field heterogeneity of crops and vertical heterogeneity of soil skeletality based on a test corn field in Kabardino-Balkaria. The NDVI vegetation index, calculated from Sentinel-2 satellite imagery, was used as an indicator of crop condition. Soil skeletality was determined by dry sieving. It has been established that the value of the NDVI index of crops on a test field can serve as the basis for indirect detection of vertical heterogeneity of agronomically important soil properties. To obtain reliable information, accurate timing of obtaining NDVI values and the crop cultivated in the field is necessary. The indicator reliability of different crops is determined by their phenology and the thickness of the potential root layer. The geography of agronomically important soil properties on the test field does not correlate with the areas of the traditionally compiled soil map. Spatial variation in corn yield on the test field (range 23%) correlates with variation in the soil skeletal profile. To use NDVI values as an indicator of spatial variation in agronomically important soil properties, it is necessary to take into account the type of crop cultivated, careful selection of the date for obtaining NDVI, as well as the availability of a priori expert knowledge about the limiting soil factors in the field, the specific phenology and agrotechnology of crop cultivation.

The results of research on the example of southern chernozem and chestnut soil are presented. Long-term use of plowing with rotation of the soil layer and the use of fallows leads to a critical state of the soil in terms of the content of aggregates measuring >10 mm and >1 mm. The introduction of notill on old arable soils leads to a general increase in the mean weighted diameter of aggregates (MWD). The intensity of restoration of the structural state of the soil during no-till in southern chernozem occurs more intensively than in chestnut soil, and the main changes are recorded in the fractions of agronomically valuable aggregates. In southern chernozem there is an increase in diameter from 6.0 mm to 9.5 mm, while in chestnut soil the MWD increases only to 7 mm. The content of erosion-susceptible aggregates <1 mm and their change depending on the intensity of agricultural cultivation in southern chernozem and chestnut soil indicates a tendency to restore the structure in the no-till variant. In southern chernozem, the content of particles of 1–0.5 mm size decreased by 1.2%, and in chestnut soil – by 6.2%. Refusal of mechanical tillage showed that, in contrast to dry aggregates, the influence of no-till on the water stability of the structure of the arable horizon is more significant and is presented in the form of fractions rearrangement. The use of no-till technology results in a reduction in the content of erosion-susceptible aggregates and increases the water stability of the structure of the arable horizon, which, together with the influence of crop residues on the soil surface, provides an anti-erosion effect. The restoration of the structural state of the soil during notill in southern chernozem proceeds more intensively than in chestnut soil. The main changes in the form of rearrangement occur in fractions of agronomically valuable aggregates.

The study was carried out in blueberry pine forests of the middle taiga subzone of Karelia. The results of complex studies of the microbiocenosis of Al-Fe-humus soils (Albic Podzols) formed on fluvioglacial deposits are presented. The methods of luminescent microscopy and substrateinduced respiration were used to assess the carbon of microbial biomass (Cmic). To study the microbiological activity of soils in relation to the mineralization of soil organic matter, the basal respiration method was used, and the metabolic coefficient was calculated. It is shown that the changes in the studied indicators reflect the natural and climatic conditions and the specifics of the soil of Al-Fe-humus genesis. The highest values of Cmic and basal respiration were observed in the subhorizons of the forest floor, and the lowest in the eluvial and illuvial horizons. The results obtained can be used as microbiological indicators in modeling carbon cycling processes in Al-Fehumus soils of forest ecosystems.

The composition of macro- and microbiota in soils formed in treatment facilities (filtration fields) of the sugar industry in the Chernozem zone of Russia was studied. Soil moisture and the abundance and diversity of organic and mineral substances entering treated plants with wastewater have a significant impact on communities of microorganisms and invertebrates. The macrofauna of the soils of periodically operating settling ponds (called checks, or carts) consists mainly of predators and phytophages; the soil of the checks that was decommissioned 45 years ago consists of saprophages, which were dominated by earthworms. All groups of macrofauna in the soils of filtration fields are characteristic of the soils of forest-steppe regions, while their numbers are significantly lower compared to the Chernozems under the oak groves of the Central Chernozem Reserve, but noticeably higher than in the surrounding arable Chernozems. The microflora in the soils of the filtration fields and the background Haplic Chernozem (Pachic) is identical in the composition of physiological groups, but differs in their number and distribution along the soil profile. Differences in the diversity and distribution of microorganisms in the studied soils depend on different water regimes, determined by the frequency and duration of exposure to wastewater and the input of sugar production waste enriched with calcium carbonate, organic matter and biophilic elements.

The soil cover of cities and towns within their administrative boundaries is composed of soils, more or less modified by the urban environment along with native, agricultural soils and non-soils. For preserving this diversity when introducing these new objects to the unified digital model of the soil cover of Russia, soil maps of 10 “test” cities have been compiled. The cities are located in several natural zones, and are intermediate in terms of their population. Mapping was performed by means of detailed purposeful deciphering, data on mapping units on the original soil map, and recent systematics of urban soils and their dependence on the urban environment. The approaches applied were supported by the experience in soil mapping of St-Petersburg, Moscow, Volgograd and few other cities. Soils were qualified in the system of Russian soil classification, and their areas, along with those of non-soils, were regarded as units in the theory of soil cover patterns. In all cities investigated, soil associations comprised urban soils per se, transitional soils including agro-soils and conventionally native ones; their ratios in the soil cover depend on both historical-socio-economical reasons and the natural enviroment.

Information about land use history is needed for investigation of soil cover transformation, evolution and degradation under human economic activity. The aim of article is to submit results of retrospective analysis of agricultural land use at the zone of light-chestnut solonetzic soil cover. Object is lands of the Experimental station “Oroshaemaya”, Volgograd region, Volga-Don irrigation system. Analysis is carried out on the bases of many space images, archive data and consultations of specialists from All-Russian Research Institute of Irrigated Agriculture. Schemes of land use at different time periods from 1970s till 2023, diagrams of dynamics of dry arable lands, irrigated lands and agricultural fallow are submitted. Nine variants of changing land areas over time are identified: 1 – dry arable land constantly from 1970; 2 – dry arable land → irrigated land → dry arable land; 3 – irrigated land → dry arable land; 4 – dry arable land → irrigated land; 5 – irrigated land → dry arable land → irrigated land; 6 – irrigated land → dry arable land → agricultural fallow; 7 – dry arable land → agricultural fallow; 8 – agricultural fallow constantly from 1970; 9 – unused lands in recent years. Duration of the same type of use for each field is determined. Statistical characteristics of plow horizon thickness in soils of Experimental station are calculated.

Digital soil rheometry is a relatively new and rapidly developing research direction that currently occupies a small niche in soil and agrophysics studies. This paper presents a review of studies based on the rheometry approach as part of soil mechanics research in different countries. The fundamental principles and equations of oscillatory amplitude sweep tests and oscillatory tests with controlled strain (resilience test) are described, with a focus on soil structure as the main object of the study. Key deformation and strength parameters (storage and loss moduli (G' and G``), the linear viscoelasticity range (LVE-range), shear stress (t), structural recovery index (R), etc.) describing the mechanical behavior of the soil at the microstructural level are discussed. This paper also highlights the influence of soil preparation: soil structure, water content, temperature, and the normal force applied during tests as parts of the research protocol – on the obtained results. Furthermore, this review examines research trends within the rheometry approach that have emerged over the past two decades of its application to soil studies. Based on the analysis of existing studies, potential directions for the further development of rheometry in soil research are proposed.