The investigations were conducted on the gray forest heavy clay loamy soils, formed on the loess-like loams, which are widely spread on the territory of Vladimir Opolye. The eluvial-illuvial profile differentiation, its different intensity and the specificity of illuvial coatings (fine dispersed clayey and humus-clayey coatings with sparse skeletal content of soil) is confirmed. The presence of the coarse wooden plant residues, thick humus-clayey illuvial coatings within the illuvial horizons speak about the forest origin of the grey forest soils in Vladimir Opolye. The micromorphology of humus horizon reflects the direction of the soil forming process and the ecological status of soils. The illimerization is the main process of the matter migration and soil profile differentiation. The mixed-layer formations prevail in the clayey fraction. Mica, quartz, and K-feldspars are the prevailing compounds of the fine and medium silt within the gray forest soils. In the silt fraction of the second humus horizon prevail quartz and feld-spar. The most of the nutrients is concentrated in the clayey and fine-silt frac-tion. The micromorphological investigations confirmed the theory, which speaks about the presence of forest (the presence of illuvial coatings) as well as steppe soils (mull humus type in the SHH, the presence of primary and newly formed carbonates) specificities in the modern soil forming process within the gray forest soil of Vladimir Opolye.

The physicochemical parameters, vegetation and biodiversity of microbiomes inhabiting 10-, 35- and 50-year-old embryonic soils (technozems) formed in the mining areas of the Kursk Magnetic Anomaly (Russia) were analyzed in the current study. Analysis of taxonomic diversity was carried out by 454-pyrosequencing of the V4 variable region of the 16S rRNA gene. All points of the chronosequence were characterized by microbiomes reliably differing in taxonomic composition. The older the dump, the higher the proportion of bacteria from the phyla Actinobacteria (mostly representatives of the Solirubrobacteriaceae family), Chloroflexi and Acidobacteria in the community. In 10-year-old dumps, bacteria from the phyla Proteobacteria, Gemmatimonadetes and Bacteroides prevailed. The most pronounced changes in the community structure at the early and middle stages of microbiological succession were demonstrated by bacteria from the genus Delftia, which may indicate their active role in the processes of soil formation in this ecosystem.

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<p>The aggregate composition is one of the key characteristics of soils. Based on the use of aggregates of different sizes, one can draw conclusions about the anthropogenic load on soils in conditions of agricultural use. We investigated the aggregate composition of soil samples of the 0-20 cm layer of soils with application of four tillage techniques: plowing, energy-saving (surface tillage, without plowing), longline (surface tillage + chisel tillage), anti-erosion (chisel tillage). Stationary experience laid in 1995. The сrops were: bare fallow, busy fallow and wheat. Soil samples were sieved with a standard set of sieves:> 10; 10-7; 7-5; 5-3; 3-2; 2-1; 1-0.5; 0.5-0.25; <0.25 mm, water resistance was determined by the Savvinov method with sieves of:> 5; 5-3; 3-2; 2-1; 1-0.5; 0.5-0.25; <0.25 mm with daily water saturation prior to analysis. Rheological parameters were studied using the amplitude sweep method on a modular compact rheometer MCR-302 (Anton Paar, Austria) with a parallel plateau PP-25 measuring system.</p><p>All 24 plots with all four treatments demonstrated an excellent water-resistant structure of agro-gray soils. The soils have a good structural state in terms of agronomically aggregates content and the structural coefficient. Water resistance of the structure is excessively high and good as well. The average diameter of the aggregates is from 3.6 to 6.1 mm, the average value is 4.7 mm. This gives us an idea of the structural condition in general, but we cannot track the structural condition of plots with different treatments in the field.</p><p>The Principal Component analysis and cluster analysis was used to determine the differences in soils of different types of use. We used STATISTICA. These statistics method successfully classified soils structural relatively treatments.</p><p>The study of the rheological properties of agro-gray soils with different processing methods showed that in the zone of linear viscoelastic behavior (LV[С1] B) during all treatments, the range of LVB did not differ significantly and averaged 0.0048% deformation. Differences were noted at Shear Stress max, for the energy-saving treatment application, the τ (632.67 Pa) was lower than the other treatments, an average of 661.83 Pa for 12 repetitions. The crossover occurred at 1.48% strain for an average of 12 reps. The smallest value for the deformation at which crossover occurred (1.22%) was observed for the variant with the use of anti-erosion treatment. The highest (1.72%) for energy efficient processing.</p><p>Thus, the use application of aggregate and rheological analyses has shown the promotion of energy-saving technologies application to form a relatively favorable structural condition of the studied soils.</p><p>The work was supported by RFBR grant No 19-29-05021 mk</p>

<p>Phosphorous is one of the most important elements for plant life, its supply is limited, so supporting the balance of phosphorous is considered to be a global challenge for the 21<sup>st</sup> century[1]. In the majority of soils, a vast amount of organic and mineral phosphorous is contained in immobile and insoluble compounds. Intensive tillage, even without fertilizers, may provide plants with resupply of phosphorous, but it leads to negative ecological consequences. [2] There is large amount of total phosphorous (0,15 - 0, 35% P2O5) in Chernozem of Kursk Region, and about 50-70% of it is organic compounds. [3]</p><p>We investigated soils with different land use: mowed grassland, soil under the wood line, soil of perennial fallow, tillage and no-till farming. The main soil is Vermic Chernozems (WRB).  Every soil sample was divided into four groups of different-sized aggregates (> 5 mm, 5-2 mm, 2-1 mm and < 1 mm) by Savvinov dry sieving method. We determined the content of organic carbon, mobile phosphorous, organic phosphorous, mineral phosphorous and total ratio of phosphorous and other elements in each group.</p><p>Cultivation increases the content of mobile phosphorous because of mineralization process. However, it leads to content reduction of organic matter. Moreover, it significantly changes the structure: the amount of aggregates larger than 5 mm increases. The content of mobile phosphorus in natural soil depends on the size of aggregates, and its amount decreases with decreasing size of aggregates. After cultivation, this trend changes, and mobile phosphorus is shared almost evenly among all groups of aggregates. Most of the mobile phosphorus is in the soil with no-till farming.</p><p>When the structure is damaged, the phosphoric state of the soil changes, which will lead to changes in the nutrition of plants.</p><p>Literature</p><p>1) Yang X., Chen X., Yang X., 2019. Effect of organic matter on phosphorus adsorption and desorption in a black soil from Northeast//</p><p>2)Агрохимическая характеристика почв СССР. Почвенно-агрохимическое районирование / Всесоюзная академия сельскохозяйственных наук им. В.И. Ленина (ВАСХНИЛ), Почвенный институт им. В.В. Докучаева ; Отв.ред. Андрей Васильевич Соколов, Николай Николаевич Розов . – Москва : Наука, 1976 . – 363 с.</p><p>3)Макаров М.И. Фосфор органического вещества почв. – М.: ГЕОС, МГУ, 2009. – 397</p>