The highest control of ragweed (Ambrosia artemisiifolia L.) in the field experiments was provided by the herbicide Primekstra TZ Gold (effect - 83%; dose - 4.5 l/ha), bent sedum (Amaranthus retroflexus L.) with herbicide Mastak (effect - 88%; dose - 0.5 l/ha), chicken millet (Echinochloa crus-galli L.) using the herbicides Varyag and Datonit Gold (effect - 57%, dose - 4.5 and 2.5, respectively), white quinoa (Chenopodium album L.) – herbicide Datonite Gold with surfactant (effect - 85%; dose - 2.5 l/ha). The greatest chemical control was provided by the application options of herbicides Varyag – 4.5 l/ha and Agent – 0.6 l/ha in the phase of 3-5 leaves of the crop in June. This treatment provide the Ponki sorghum hybrid grain yield increase 24-27% compared to the control.

It is found that 0–30 cm arable layer density was in the range from 1.09 to 1.32 g/cm3 regardless of the tillage system at the beginning of spring field work. The compaction of 0–30 cm soil layer (by 0.02–0.14 g/cm3) was at the shallow mulching due to the loosening depth reduction to 12–14, 14–16 cm. There is an inversely proportion between soil porosity and density, i.e. the higher density, the lower pore volume in the soil. We can increase the porosity (up to 54.3 %) and improve the soil aeration (30.3–32.4 %) due to the primary tillage (especially plowing and chisel loosening) and crop residues, which leads to soil decompaction and the significant pore formation. At the end of field crop vegetation, there was a natural compaction of the soil due to natural and technogenic factors. As a result, the pore volume decreased by an average of 2.7–5.7 % under moldboard plowing and differentiated tillage system and by 1.5–3, 5 % – shallow nonmoldboard loosening. In the spring and during the growing season, the compaction of porous soil under the moldboard plowing and differentiated tillage system has always been more intensive compared to shallow nonmoldboard tillage. It is established that on the recultivated lands the total porosity and aeration porosity indicators in the model with zonal soil at long-term use of fertile layer gradually increased (52.5 → 59.2 → 60.3 %), however with the completion of intensive use of perennial agrocenosises they decreased to 56.4 %. For the model with loess-like loams, the patterns were similar. The increase of total porosity and aeration porosity in model with clays compared with the initially formed technosoils was observed. Key words: field crops, tillage system, density, porosity, chisel tillage, disking, bulk fertile layer.

The study of the properties of disturbed soils and rocks makes it possible to establish the parameters of the natural fertility of the studied substrates, to detect limiting factors, and to determine a set of restoration measures. The tested overburden rocks with the largest stratigraphic share of the open-pit quarries of the Nikopol manganese and Kerch iron ore deposits were loamy-like loess (Quaternary) and grey-green clay (Neogene). There is a certain parametric relationship between texture, density, porosity, the structural and physical state of different models of artificial reclaimed profiles. The composition and properties of rocks of edaphic structures of technosoils differ according to zonal natural and climatic conditions of the subzones of the Ukrainian Steppe. Loess-like loam and grey-green clay of the Kerch iron ore deposit are distinguished by a higher bulk density, lower porosity, and wilting moisture compared to samples from the Nikopol manganese ore basin. The use of the rotor complex leads to mechanical destruction and an increase in the content of small particles of rocks. Self-compacting processes occur to a large extent in multilayer structures. This pattern is observed at the boundary of the backfill differentiated in texture layers of technosoils. This indicates the existence of a barrier that prevents the relationship of edaphic properties between substrata stratums. Optimal ratio of clay minerals provides a rather high capacity of grey-green clay for water absorption. The model of technosoil composed of grey-green clay differs in a larger number of water-resistant micro-aggregates. The best conditions for land reclamation are connected with including grey-green clay in two- and three-layer constructions of technosoils, providing a waterproofing effect.