Search

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 specific features in accumulation and distribution of organic carbon and nitrogen in the aggregates of typical, ordinary, and southern chernozems (Protocalcic Chernozems, Endocalcic Chernozems, and Pantocalcic Chernozems, respectively) during the transition from conventional farming to a no-till system are evaluated. For this purpose, the contents of organic carbon and nitrogen were determined in different aggregate size fractions (>10, 10–2, 2–1, 1–0.25, and

The application of direct seeding technology on typical and ordinary chernozems in the European territory for four years has resulted in a significant increase in the content of soil organic matter in regions with sufficient moisture supply and some tendency of its in regions with insufficient moisture supply (Stavropol region). A tendency for an increase in the available phosphorus and exchangeable potassium contents has also been observed. The yield of crops and profitability of production in the course of long-term (> 7 yr) application of direct seeding are approximately 30% higher than in the case of traditional technologies. Application rates of glyphosate-containing herbicides to control weeds can be significantly reduced in the case of using cover crops, modern biochemical methods, and strict compliance with the technology of herbicide application. Taken together, these measures ensure an increase in the number and species diversity of microorganisms that can suppress pathogenic microflora significantly reducing the damage to plants from diseases and pests.

This article presents the results of research on the impact of no-till technology on the natural bulk density and macro- and microaggregate composition of the topsoil (0–20 cm) in different subtypes of chernozems before sowing and during the growing season. Haplic Chernozems (Loamic, Aric, Pachic) and Haplic Chernozems (Loamic, Aric) were studied. For all chernozems, improvement of physical properties was recorded when no-till was introduced in comparison with the control. Four and six years of crop growing without tillage did not cause any compaction of Haplic Chernozems (typical and ordinary subtypes). On the plots with direct sowing, the microaggregate composition of typical chernozems was characterized by a higher proportion of coarse fractions (>50 µm) in comparison with the control. Probably, this indicates the development of microaggregation similar to that under natural cenoses, which are characterized by a relatively high content of the fraction 50–250 µm, upon the transition to no-till. In all subtypes of chernozems under no-till, the water stability of aggregates increased. The share of agronomically valuable aggregates in typical chernozem also increased, which may be associated with an increase in the input of water-soluble organic matter into the soil during no-till, because this technology excludes translocation of plant residues into the soil. In southern chernozems, this effect was manifested only for fractions >7 mm, while water stability of finer aggregates was mainly due to the calcium content regardless of the type of tillage.

Data on the aggregate-size distribution (dry sifting method) in humus horizons of chernozems were processed by principal components analysis (PCA) with the centered logratio transformation of the initial data set. The analysis of the positions of treatments in the space of principal components coupled with the analysis of eigenvector magnitudes made it possible to identify several size fractions of aggregates, whose contents in the soils reflect soil degradation or progradation processes. These groups fitted well to the partial lognormal curves of aggregate sizes. In addition, the distribution of water-stable aggregates in coarse aggregate fractions (>10, 10–7, 7–5, and 5–3 mm) was analyzed. The integral analysis of the obtained data made it possible to propose the following conceptual model of the recovery of the structure of tilled chernozems. In the course of tillage, soil particles 10 mm) water-unstable aggregates (clods). With the removal of tillage loads, large aggregates interact with fresh organic matter, and the water stability of aggregates increases. At the same time, the largest aggregates (mainly >10 mm) tend to transform into aggregates of smaller sizes.

The functional role of nitrogen in the formation of crop yield on chernozems under conditions of traditional and direct seeding (DS) cropping systems is considered. In the course of long-term experimental studies of DS cropping system on chernozems, considerable experience has been gained and has found efficient practical application. It is shown that the effect of nitrogen as the most important element in the composition of humic substances influencing the fertility of chernozems depends on the variability of environmental factors, the forms and rates of nitrogen fertilizers, the rotation systems, and the soil treatment technologies. The DS cropping system has been tested for 4–10 years on experimental fields of the Stavropol Agricultural Research Institute and in a number of farms in Stavropol region. The obtained data on the yields of cereal crops and the application of fertilizers attest to the importance of the formation of a mulching layer of plant residues on the surface of ordinary and southern chernozems in the DS systems. This layer contributes to a gradual accumulation of nitrogen, protects the soil from erosion, and increases the number and mass of earthworms. Nitrogen in the DS cropping systems on chernozems in Russia is characterized by the high mobility and the capacity for considerable transformation. In this context, further investigations and special experiments are necessary to gain better knowledge of the behavior of nitrogen in different cropping systems. In particular, the relationships between nitrogen fluxes, agrophysical soil properties (aggregate-size distribution at the macro and micro levels), and specificity of the organic matter in different subtypes of chernozems under different cultivation technologies have to be clarified. In general, the role of DS cropping systems in farming practices has become more significant in the recent years; application of the DS cropping system is considered a positive factor in maintaining and restoring soil fertility.

An overview of modern ideas on the ecological and geochemical state of soils and vegetation in the sites of landfills and municipal solid waste storage is presented. The technogenic impact on the environment and soil is determined by the (1) withdrawal of land for landfills, (2) production of filtration water with toxic components upon decomposition of solid wastes, and (3) biogas generation. The heavy metal pollution of surface soil horizons is characteristic for the sites of solid waste storage and their impact zones irrespectively of climatic conditions, ways of waste management, and stages of the life cycle. At the same time, heavy metals accumulate in ruderal herbaceous plants. Changes in the geochemical and microbiological characteristics of soils and disturbances in the plant cover are not restricted to the area of the designated sanitary protection zone. Buried landfills, where the decomposition of organic matter under anaerobic conditions results in the production of carbon dioxide and methane with their concentration in the soil and ground air also become dangerous for the environment. In the sites of landfills and municipal solid waste storage, weakly developed surface and chemically transformed soils, technosols and technogenic surface formations are being formed.

The article assesses the relationships between the morphological properties of agrochernozems and yield of peas on the plots, experience with different methods of basic treatment (moldboard plowing at the depth of 20 - 22, 25 - 27 and 14 - 16 cm, moldboard plowing to a depth of 14 - 16 cm, combined midwater moldboard, mid-water subsurface, surface to a depth of 6 - 8 cm and zero tillage) is inherent in V.V. Dokuchaev Research Institute of Agriculture of the Central Black Earth strip, in the fall of 2014. The research was conducted in 2015 - 2016, with the application of mineral fertilizers (N60Р60К60) and unfertilized background. The highest pea yields in the fertilized as the background, and without the use of fertilizers was observed in dumping plowing and especially in the variant with deep moldboard plowing, which creates in comparison with other ways of handling the best conditions for the growth and development of peas. The lowest yield of pea was obtained with zero processing. Apparently legalistic migrational-mizelial agrochernozems the Central Chernozem zone of minimum tillage in the cultivation of peas are not effective, what is evident already in the first year after the laying of experience with different basic treatments. As shown by the results of applying multifactor analysis of variance studied the mapping properties of the soil can have the same significant impact on the yield of agricultural crops, as options for the field experiments aimed at assessing the impact of various treatments on yield.

Current concepts of soil transformation and contamination in iron ore mining areas have been reviewed. Changes of soils and ecosystems in the mining areas are among the largest-scale impacts of economic activity on the nature. Regularities in the radial differentiation, spatial distribution, and accumulation of heavy metals in soils of different natural zones are analyzed. The effects of mining technogenesis and gas–dust emissions from enterprises on soil microbial communities and fauna are considered. In zones of longterm atmotechnogenic impact of mining and processing plants, the stable state of ecosystems is lost and/or a new technoecosystem different from the natural one, with own microbial cenosis, is formed, where communities of soil organisms are in the stress state. In the ore mining regions, embriozems are formed, which pass through specific stages of technogenically-determined development, as well as technosols, chemozems, and technogenic surface formations with variable material compositions and properties. Technogenic soils and soil-like bodies form a soil cover differing from the initial one, whose complexity and contrast are not related to the natural factors of differentiation.

Intensification of agriculture leads to development and implementation of new soil conservation technologies that reduce degradation processes, as well as the development of methods for monitoring and controlling these technologies. Spectral indexes method as one of the methods of remote sensing is one of the most modern methods for solving this problem. This research was conducted on three production fields located in the territory of the Budenovsky district of the Stavropol territory, where plowing with the layer turnover and no-till technology were used. Aim of this research is analysis of the possibility of using 8 spectral indices to identify different types of soil cultivation. The study found that the most informative differences between tillage systems are provided by NDTI, STI and NDI7, which use the SWIR 2 spectral range for calculations. In addition, the classification of objects based on these indexes by the K-means method gives the highest accuracy.

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.

Artificially created soil-like technogenic formations (STFs) of soccer fields are developed under combined action of intense technogenic and natural factors and processes, which cannot but affect the structure and biological activity of their microbial communities and mesofauna. The microflora of the STFs is very similar to the microflora of the background soddy-podzolic soils of Moscow oblast with respect to the composition of the physiological groups of microorganisms. However, they are drastically different in their quantitative characteristics. The numbers of all the trophic groups of microorganisms, except for the microscopic fungi, in the STFs are much higher than those in the zonal soils. An increased biological activity of the STFs is due to regular watering, heating, application of sand and mineral fertilizers, and technogenic turbation processes. The mesofauna of the STFs is represented by several ecological groups of earthworms, including soildwelling (endogeic) earthworms (Aporrectodea caliginosa), epigeic earthworms dwelling at the soil-litter interface (Lumbricus rubellus), and litter-dwelling earthworms (Eisenia foetida).

A soccer field can be considered a soil-like technogenic formation (STF). According to the theory of soil cover patterns, the artificially constructed (anthropogenic) soil cover of a soccer field is an analogue of a relatively homogeneous elementary soil area. However, the spatial homogeneity of the upper part (50–80 cm) of the STF of soccer fields is unstable and is subjected to gradual transformation under the impact of pedogenetic processes, agrotechnical loads, and mechanical loads during the games. This transformation is favored by the initial heterogeneity of the deep (buried) parts of the STF profile. The technogenic factors and elementary pedogenetic processes specify the dynamic functioning regime of the STF. In 50–75 years, the upper part of the STF is transformed into soil-like bodies with properties close to those in zonal soils. Certain micro- and nanopatterns of the soil cover are developed within the field creating its spatial heterogeneity.

The paper discusses the impact of direct seeding technology on volumetric weight of arable layer, content (%) of air-dry and water-resistant aggregates (mm), as well as agronomically valuable aggregates during dry sifting The fact of using the direct seeding technology for four years in grain crop rotation did not lead to an increase in volumetric weight of an arable horizon. This increases the content of dry agronomically valuable aggregates and the coefficient of structure increases. The direct sowing positively affects the water-resistant structure of typical chernozem, increasing the content of water-resistant aggregates in dry fraction > 10 mm from 68.7% (plowing option) to 80.7%.

Production of phosphorus-containing fertilizers is related with the problem of reclamation of phosphogypsum dumps formed during the processing of Apatite-nepheline ore. In this regard, some attention should be paid to biological remediation as the most effective ecological method. Biological reclamation is one of the ways to protect the environment in the formation of phosphogypsum dumps. In this article, we propose a method for assessing the effectiveness of remediation using phyto monitoring using satellite data, which are used as the results of remote sensing. The proposed method allows estimating the volume and state of biomass of plants forming vegetation cover on the surface of man-made massif.

Upper groundwater level (verhovodka) is considered as one of the factors of soil waterlogging associated with both the natural features of the territory and anthropogenic impact. On the case of one of the watershed areas of the steppe, where many years of scientific research are being conducted to assess the minimization of agrotechnical methods of cultivation of agricultural crops, a soil-geomorphological profile 1 km long was studied on which 8 wells were drilled, to a depth of groundwater with water sampling for salinity and chemical composition. The results showed that there are no visual signs of gleying in the profile of chernozems, the groundwater level correlates with the daytime surface of the relief, and in the soil-ground layer at depths of 2.0-3.9 m there is a horizon of "chocolate" clay, which forms a local aquiclude. Sulphate-sodium composition of fresh waters potentially dangerous for the salinization of chernozems at a high level of GWL (ground water level). Verhovodka is important to desalinating groundwater located above the confining layer, playing the role of a local factor of desalinization of the soil-ground layer of sediments.Since 2009, in the Kamennaya Steppe, according to the data of the main hydrogeological well No. 1, the GWL is constantly at a depth of over 7 m, which characterizes the beginning of the next natural-anthropogenic aridization. In conditions of a lack of surface moisture, no-till techniques should be recommended as a factor in reducing evaporation and moisture accumulation in the steppe chernozems.

The variability of morphometric indicators of typical chernozems is considered based on long-term field experiment in a grain 4-field crop rotation (winter wheat, corn, barley, peas) to assess the impact of plowing as a traditional farming system that uses soil treatment and no-till, in which plowing is not used. On the example of four experimental fields (each with an area of 2.4 hectares), the variation of indicators associated with the features of the soil cover structure and the applied farming systems was revealed. The tillage leads to an increase in the thickness of the soil profile leached from carbonates, and direct sowing leads to its decrease. The highest variability degree is found in the boiling depth of soil. It is shown that the tillage leads to the homogenization of the soils surface layer and the transformation of the soil cover structure, as a kind of ”insurance system " against weather risks reducing its effectiveness. The direct sowing usage leads to the restoration of degraded properties and natural of soils heterogeneity in the soil cover structures, which can be considered as a process aimed at ecological improvement of both specifiс soil sites and the soil cover structures. The mutual influence of the soil cover structure and agricultural systems can be traced in time and space. The soil structure and the cultivated crops yield related to the sustainability of agrosystems to adverse climatic conditions and other risk. For these it is necessary monitoring soil as the basis for the qualitative assessment of soil and selection of the most optimal directions of agriculture development, a new technologies development in the production of agricultural products.

The variability of the carbonate profile of chernozems was studied during the long-term field experience on minimizing treatments and using no-till. The structure of the soil cover of the experimental fields is dominated by typical chernozems (Voronic Chernozems Pachic. WRB) – 82% in combination with over – dug – 12 % (zooturbated) and leached-6 %. Boiling depth and pH were used as the main properties that diagnose the acidity of soils and their variability in space and time. During one rotation (4 years), the acidity of chernozems on average showed a tendency to decrease at depths of 0-10 and 10-20 cm, respectively, by 0.18 and 0.12 pH units. The process of soil alkalinization is generally due to the natural variability of climatic parameters during the experiment. The greatest changes in acidity between technologies are associated with the use of no-till, for which significant differences in pH in a layer of 10-20 cm were revealed from all technologies using the processing of chernozems. In the conditions of the modern climatic situation in the subzone of typical chernozems, the use of no-till also leads to a decrease in the variability of the pH in the field space. In the provision of soils with nutrients, this can affect the technology and doses of mineral fertilizers.

The influence of different systems of soil cultivation is considered - traditional (recommended) technology and direct sowing, which is increasingly used under dry conditions of the region. The rehabilitation of the degraded southern chernozems and dark chestnut soils structure during 13 and 7 years of direct sowing, respectively, has not been established. It takes much longer to rehabilitation the aggregate state of soils, which is currently in a critical condition of the content of aggregates> 10 mm in size and the sum of agronomically valuable aggregates. The soils under 60-year treeline, as a control, showed a satisfactory range of aggregates, which indicates a high degree of soil degradation in the past and a long period of their recovery time. The effectiveness of direct sowing usage in the cultivation of a wider range of grain and row crops (winter wheat, sunflower, peas, chickpeas, rapeseed, buckwheat, corn) is due to the peculiarities of agricultural technologies. Abandoning of naked fallows and soil treatments with the simultaneous use of plant residues and cover crops on the soil surface between the harvest and sowing of winter crops provides an anti-erosion effect and, as a consequence, a decrease in physical evaporation, an increase in moisture and biota reserves, an increase in microbiological processes, which are noted in the form trends in improving the agrochemical and agrophysical properties of soils.