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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

The results of the field experiment have been analyzed, it was set up on two experimental fields (with an area of 2.4 hectares each), where two different agricultural techniques – traditional and no-till – were applied. Diagnostics of morphometric parameters of typical chernozems such as: the thickness of the A1 horizon, A1 + AB horizons and the depth of carbonates reaction with 10% HCl, has shown that some changes in soils and soil cover had occurred in the fields over 8 years. The integral indicator of soil productivity is the thickness of the humus horizon, it demonstrated trends to decrease and increase in the soil cover structure of the experimental fields with different compositions of chernozem subtypes. The trends result from both climate change and periodic dry periods, which are not typical of the region, and from the change of traditional technology to no-till. The carbonates leaching from chernozem profiles in all variants of the experiment decreased, which correlates well with climatic indicators, changing with the seasons of the year. Chernozems with thin humus layaer and reacting with HCl close to the surface do not require liming. The revealed changes are not statistically significant, they reflect the resistance of chernozems to the variability of natural and anthropogenic factors of soil formation. Crop residues on the soil surface under no-tillage reduce physical evaporation, which contributes to moisture accumulation in the soil. The use of cover crops in winter also increases the moisture reserves, which are consumed by the plants during the summer growing season. Information on the transformation of morphometric parameters allows making temporal and spatial corrections in the applied agricultural practices (crop rotation, fertilization, the use of cover crops, herbicides and pesticides).

The key feature of the no-till technology is the preservation of crop residues on the soil surface. Crop residues quantitative assessment is an important task when introducing technology into production. On the basis of field and remote sensing data, different approaches to this assessment are considered. The research was carried out in the Budennovsky district of the Stavropol Territory in the fields of farms using both traditional technology (TT) and no-till (ПП). Images of the Sentinel-2 system were used as remote sensing data, on the basis of which the spectral indices NDTI and NDVI were calculated. Three methods were used to estimate the projective cover by plant residues: 1) weight accounting of plant residues per unit area; 2) field determination of the projective cover by the method of line transects; 3) desk analysis of photographs of the soil surface. Based on the obtained results, models of the linear dependence of NDTI values on the projective cover of the soil surface with plant residues were constructed. The possibility of quantitative accounting of plant residues only on the basis of remote sensing data was also analyzed. The highest coefficient of determination (R2 = 0.97) with the smallest square root of the standard error (RMSE = 7.93) was obtained by modeling based on the analysis of photographs of the soil surface covered with plant residues. Based on the model of the dependence of NDTI values on the projective cover of plant residues obtained as a result of the analysis of photographs based on Sentinel -2 satellite data for the growing season 2020–2021, data were obtained on the dynamics of soil coverage with plant residues (CRC) on the scale of a single field an d different tillage technologies. As an approbation of the approach and an assessment of its use for solving production problems, the dynamics of the projective cover with plant residues was analyzed under different crops and different relief conditions. An analysis of the dynamics of CRC values made it possible to distinguish between different stages of crop cultivation under traditional technology (TT) and no-till (ПП), and also on the scale of an individual field revealed the heterogeneity of the projective soil cover with plant residues associated with the features of the mesorelief.

The analysis of long-term observations in the Kamennaya Steppe (over 125 years) for climatic parameters (air temperature and precipitation), ground water level, vegetation species composition revealed the main trends in their variability. Since 1969 there has been an increase in temperature and a reduction in temperature fluctuation during the year. Over the last 30 years, the difference has reached 1.90, and over the last decade it has grown by 0.40 due to the cold season. The amount of precipitation over the same 50-year period has not changed much. In total, an increase of 45 mm was observed over the decade (1999-2008). In the XXI century, there has been registered an increase in the amount of precipitation in the cold season by 12.7% and a decrease in the warm season, which creates certain prerequisites for climate continentality mitigation during the annual cycle. During the first 70 years of observations, the groundwater level in the well No. 1 was on average at the depth of 6.5 m (5.7-7.3 m). At the end of the XX century and at the beginning of the XXI century, there was marked a pronounced rise in the ground water level, the average depth was 3.8 m, which coincided with the growth of average annual temperature and an increase in total rainfall. In this period changes in the long-term regime of ground and surface soil moisture resultedin expanding the area of wetlands and hydromorphic soils on the territory of the steppe. The period of 2009-2018 is characterized by a continued increase in average annual temperatures and a decrease in precipitation, which may lead to a seasonal change in temperature and precipitation to milder and wetter winters and warmer and drier summers. Transformation of vegetation for 100 years of observations had several stages with a general trend to change the steppe grasslands to meadow-steppe, shrubs and woody species.

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.

When setting a long-term field experiment in order to study the impact of direct sowing technology on soil properties it is necessary to take into account not only the known requirements, but a comprehensive analysis of soil heterogeneity as well. The article presents the results of detailed topographic and soil-agrochemical mapping with estimation of variability of morphological and agrochemical properties of typical chernozems studied on four experimental fields of 2.4 ha area each.

The impact of soil cultivation methods (tillage with soil overturning at a depth of 20-22 and 14-16 cm, beardless plowing and surface treatment respectively at a depth of 14-16 and 6-8 cm, and also zero or minimal tillage)) on biological activity of various ecology-trophic groups of microorganisms on agronochernozems of the Kamennaya Steppe (Voronezh oblast) using classical inoculation methods on elective media. It is shown that chernozems are highly resistant soils that are resistant to external impacts, preserving high biological activity even at the maximum mechanical treatment. Tillage with soil overturn leads to aeration of the arable horizon and the activity initiation of aerobic microorganisms of the carbon cycle, responsible for the mineralization of both complex and simple organic compounds of the soil. The contribution of microorganisms of the nitrogen cycle (nitrate-reducers and nitrogen fixers) to the overall biological activity of migratory-micellar chernozems of arable land and layland was minimal. The level of mechanical impact on the soil affects the quantitative indices and biological activity of microorganisms in the soil - the stronger the effect, the deeper layers are affected. The processes of entrance for fresh organic matter prevail over the processes of mineralization practically in all variants of the experiment, except for tillage with the soil overturn to a depth of 14-16 cm, as indicated by the values of the mineralization coefficients. The strongest humus-accumulative effect was observed in the variant with zero treatment, which is maximally approximated to such processes, occurred in a layland. Minimal soil cultivation will help to preserve the unique structure of chernozem soil, to increase the flow of fresh organic remains, to preserve the high biological diversity which is specific for natural biocenosises.

In this work we consider the processes of degradation and changes of properties of gray forest soils and migration-mycellar chernozems as a result of agrogenesis and erosion. We also consider progradation processes, which lead to forming of anthropogenic deeply transformed soils, and post-agrogenic processes, which are characterized by reclamation of the natural parameters of soils. The most dramatic changes occur in the composition of profiles, and also in morphological, physical and agrochemical properties. The results of investigations allowed us to determine four trends of the development: agrogenically-degradational and also agrogenically progradational, which is familiar for large areas of arable lands, and also postagrogenic nature-like, which is typical for laylands. The most of the soils, involved in agricultural activivities, are affected by degradation as a result of agrogenesis. This is manifested in the developments of processes of surface and linear erosion, in the decrease of humus content and the thickness of humus layer of the soil mass. There are also observed such processes as forming of compaction under the arable layer, the changes in structure and the decrease of water resistance of aggregates. In the agro-gray soils of agrogenically-degradational trend we observe the significant decrease of the thickness arable layer and humus content, and as contrary, the increase of silt and physical clay content, and also the increase of solidity values in comparison to the gray soils. In the same agrogray soils of agrogenically-erosional trend, we observed the increased density and solidity, the increase of non-agregated material content, the decrease of humus content, the decrease of melkozem content and the decrease of fine fraction content, which are valuable for plants. The results obtained are the additional information base for the convertion of Uniformed State Register of the soil resources of Russia on a regional and local level.

Проанализированы климатические параметры (осадки, температура, давление и ветровой режим), определяющие характер пустынного почвообразования и формирования в Ливии гамад, почв различного генезиса и структуры почвенного покрова. На общем фоне аридных условий важную роль играют атмосферные процессы. Большую часть года над Сахарой формируется высокое атмосферное давление, определяющее направленность ветров к побережью Средиземного моря, где глубокие циклоны в холодное время года создают барический градиент и являются катализатором зарождения сильных ветров “гибли” в нагорьях Ахаггар и Тибести, расположенных в центральной Сахаре. Стекая по склонам нагорий и ступенеобразным поверхностям гамад, ветер превращается в фён - мощный фактор денудации коренных пород и формирования каменисто-щебнистой поверхности гамад, а также эоловых аккумуляций по их периферии. Исследования почв и структур почвенного покрова аллювиально-пролювиальной равнины выявили формирование серо-бурых пустынных слабодифференцированных карбонатных почв (Skeletic Gуpsisols (Hypergypsic)) и литоземов (Hyperskeletic Leptosols (Yermic)), которые в комбинации образуют литогенную микроструктуру. На плато Хамада аль-Хамра доминирующим типом являются серо-бурые пустынные карбонатные почвы (Саlcic Gуpsisols (Yermic)) с рубефицированным красноцветным горизонтом в средней части профиля. Микроструктура представлена слабоконтрастной комбинацией почв разной мощности - ташетом. Выявлены различия в формировании коркового горизонта и “пустынной мостовой” серо-бурых почв бореальных условий почвообразования с субтропическими и тропическими. Из-за напряженного ветрового режима в почвах гамад Ливии корковый горизонт менее плотный и мощный.

Under consideration is the classification of soils and soil-like formations in special landscapes and the football ground in particular. The latter is usually represented by soils subjected to human impacts of varying intensity: from weakly transformed by technogenic processes to artificial soils or technogenic superficial formations. The objects of research are more than 40 football grounds in Russia and the Republic of Byelarus. They differ in the age (exploitation time), regular and intensive technogenic loads, natural conditions and soil properties. The football grounds under study were divided into 3 groups: sports-ground at the age of its exploitation (less than 5 years), sports-mass grounds (30-50 years) and professional football grounds (50-75 years). Every group of football grounds is characteristic of soils and technogenic superficial formations represented by (1) technogenic-natural soils, (2) technogenically transformed soils and (3) technogenic superficial formations. The first two groups include the surface-transformed and disturbed soils, the natural profile of which is weakly changed. The technogenic superficial formations artificially constructed on the buried horizons of natural soils are highly subjected to technogenesis. In dependence on natural and technogenic conditions, age or exploitation time, peculiar features of soil stratum on football grounds it is possible to recognize a postlithogenic type of soddy-podzolic soils as well as 3 synlithogenic types represented by techno-soddy podzolic soil and 2 types of technogenic superficial formations including primitive and soddy quasizems. The evolution trends are striving to develop three subtypes of soddy quasizems under all the bioclimatic conditions including lessive, gleyic and solonetzic ones, whereas under humid conditions of the Moscow region there exist 5 subtypes of techno-soddy podzolic soils represented by lessive, gleyic, technogenically overcompacted, residual-carbonate and chemically polluted ones.