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Carbonate system determines the basic processes of soil formation and evolution. The aim of research was to show the importance of chemical Carbonate Calcium Equilibrium (CCE) in soil solutions. CCE causes a degree of soil solution’s saturation with CaCO3 as a factor of carbonate geochemical cycle. CCE depends on chemical composition, pH, Eh, buffering properties of liquid phase, dissolution, migration, precipitation of carbonates in the soil profile and landscape, ion exchange processes at the interface of soil solid and liquid phases. At high ionic force in soil solution are formed electrically neutral ion pairs ????30; CaSO40, MgCO30, MgSO40 and charged ion pairs CaHCO3+, MgHCO3+, NaCO3-, NaSO4-, CaOH+, MgOH+. The object of research-saline soil of dry steppe zone of Southern Russia. This soil is moderately thick, solonized, humus 2.6%, physical clay 47.7%, clay 29.5%, CaCO3 0.15% (up to 3-10% at the depth of 0,8-1,5 m), pH = 7.8-9.0, readily soluble salts in soil solution from 0.2% in 0-5 cm to 3.5% in 70-80 cm, exchangeable cations: Ca2+ – 182 mmol kg-1, Mg2+ – 65 mmol kg-1, Na+ – 34 mmol kg-1. The soil solution was extracted from soil layers at the depth of 0-150 cm. Ion’s composition of the soil solution was determined using standard analytical methods. The mathematical model shows the real state of associated ions at high ionic strength of saline soil solution. On the basis of algorithm CCE a computer program was developed The concentration of free and associated ion form is a result of iteration beginning from analytical ion concentration considering ion material balance, linear interpolation of equilibrium constants, method of ionic pairs, laws of: Initial concentration preservation, operating masses of equilibrium system. Concentration constants of ion pair dissociation were calculated following the law of operating masses. Were determined a quantity of ion free form and the coefficient of ion association γe as a ratio of ion’s free form to its analytical content γe = Cass/Can. Because of association of ions, which differs in soil layers: The chemical equilibrium in soil solution determines high mobility of carbonates, transformation of solution, carbon sink from soil.

Unregulated accumulation of phosphogypsum leads to dangerous geochemical flows with an avalanche effect. As a new option for the application of phosphogypsum, its dispersed placement in the small aggregate chernozem system at a depth of its modern anthropogenic illumination was described. A milling method for treating a soil layer of 30–60 cm was developed. Phosphogypsum and soil interact and agrophysical soil properties can be improved. The anthropogenic eluvial-illuvial structure of the soil profile can be eliminated. The morphological, agrophysical properties and soil moisture conditions, thermodynamic processes with Pb2 +, Cd2 + ions, the morphological parameters of the root system and the yield of sunflower after application of phosphogypsum during its utilization by dispersing in the soil layer of 30–60 cm were studied. Improved soil properties and conditions for development of the rhizosphere, passivation of heavy metals as a result of the carbonate-calcium equilibrium in the soil solution were described. The ecosphere and the agricultural production effect of phosphogypsum utilization in chernozem were substantiated.

The effect of anions on the adsorption and mechanism of interaction of zinc cations with a solid soil phase was established. Acetic acid anions had the greatest influence on bond strength between metal and soil particle surfaces, while the effect of nitric acid anions was the lowest. The difference in amount of mobile forms of zinc extracted by the soil depends on the dose and form of the zinc. The influence of the attendant anions on the content of mobile metal forms in the soil decreases in the order: PO42 − ≈ Cl− > NO3− > SO42 − > СН3СОО− > О−.

The biogeosystem engineering is considered, and the verification of the biological, recreational, productive-economic resources of the soil-reclamation agrotechnics based on the rotary milling subsoiling is performed. The test data of the first-generation rotary milling subsoiling facility is provided. A fundamentally new engineering solution is developed. The structural synthesis of the new rotary milling subsoiling facility options in the second- and third-order approximations is performed. The draught minimization of the new facility under its operation is provided. The optimization criterion for the engineering solution synthesis results is developed; the facility parametric synthesis is performed; comparative energy characteristics of the new facility and prototype are given. The rotary milling chisel plough—gearbox transmits torque without passive draught to the tillage tool, and to the subsoiling one that operates full dip being horizontally located and moving progressively at the given depth of 20‒48 cm. The possibility of the reliable operation in the soil of the new engineering solution interconnect system is proved. The assignment and reliability indices of the subsoiling rotary milling facilities are given. Performance physics and physics of failures are considered; the new engineering solution reliability is proved. The fundamentally new principles of the innovation project development and the implementation of the land development plans in Russia are proposed.

The long-term (30 year) dynamics of a solonetz soil complex composed of solonetzic light chestnut soils and chestnut solonetzes under standard conditions and with the application of agromeliorative measures are considered. When the standard zonal agricultural practice is used, the soils of the solonetzic complex have unfavorable agrophysical, chemical, and physicochemical properties and low productivity. After 30 years of the standard three-level tillage of the soils to a depth of 40–45 cm, the productivity of the biogeocenosis decreased. Thirty years after a single rotary-milling subsoil treatment of the 20- to 45-cm soil layer using a milling tool FS-1.3, there were no morphological features pointing to the restoration of the solonetzic process. The humus content in the 0-to 20-cm and 20-to 40-cm soil layers was 2.3 and 1.7%, respectively; the content of adsorbed Na+ in the 20-to 30-cm layer was 11.6% of the total exchange capacity, or 38% lower than its content in the reference soil. The additional yield reached 30–70% and more of that obtained with the standard agricultural technology used during the whole period under investigation. The method of systems biogeotechnology (systems bio-geo engineering) is proposed as a method for the preventive control of soil evolution and the maintenance of the stability and high productivity of the soil cover.

Dynamics of material composition, migration and accumulation of salts is determined by chemical equilibrium in soil solution. Soil solution contains associated electrically neutral ion pairs CaCO30; CaSO40, MgCO30, MgSO40, charged ion pairs CaHCO3+, MgHCO3+, NaCO3-, NaSO4-, CaOH+, MgOH+. Calculation method is proposed for quantitative assessment of real ion forms in the soil solution of chestnut solonetz soil complex. Were proposed equations to calculate free and associated forms of ions. To solve the equations were used an iteration, a linear interpolation of equilibrium constants, a Method of Ionic Pairs including a law of initial concentration preservation, a law of the operating masses of equilibrium system, the concentration constants of ion pair dissociation on the law of operating masses. Was determined the quantity of ion free form and a coefficient of ion association as ratio of ions free form to analytical content I³e = Cass/Can. The association of ions varies in individual soils and soil layer. Increasing soil solution salinity amplifies the ions association. In form of ionic pairs in soil solution are: 11.8-53.8% of Ca2+; 9.4-57.3% of Mg2+; 0.7-11.9% of Na+; 2.2-22.3% of HCO3-, 11.8-62.7% of SO42-. The ion CO32- is high associated, the share of ions in associated form is up to 92.7%. The degree of soil solution saturation was obtained for three level of approximation accounting on analytical concentration, calculated association coefficient, calculated coefficient of association. Relating to thermodynamic solubility product S0, the mathematical product of analytical ionic pairs indicated super saturation of soil solutions up to K1 = 100, taking into account calculated coefficient of association ion activity super saturation of soil solutions is absent, K3≈1. Only for solonetz chestnut meadow K3≈2-5. The soil solution saturation degree in soil profile and laterally in landscape varies. The quantitative assessment of real ion forms in the soil solution allows explain evolution of landscape of salted soils, structure of soil cover. Calculations fulfilled show that a possibility of soil degradation scenario taking into account the laws of association of ions in soil solution is much more probable and dangerous than it was assessed before. New understanding of water-salt transfer, geochemical barriers and ecological functions of soil will help to improve rainfed and irrigational agriculture.

The chemical equilibrium in the soil solution determines the dynamics of its material composition, migration and accumulation of salts. In the soil solution are formed electrically neutral ion pairs ÐiаÐiО3°; CaSO4°, MgCO3°, MgSO4°, charged ion pairs CaHCO3+, MgHCO3+, NaCO3-, NaSO4-, CaOH+, MgOH+. The calculation method proposed for quantitative assessment of real ion forms in the soil solution of solonetz taking into account the ions association. Determination of real condition of the main ions in soil solution is based on ion association and its influence on physical and chemical properties of solution. Were calculated the free and associated ion form concentration according to analytical ion concentration. Were used an iteration to solve the equations of ion material balance, a linear interpolation of equilibrium constants, a Method of Ionic Pairs including a law of initial concentration preservation, a law of the operating masses of equilibrium system, the concentration constants of ion pair dissociation following the law of operating masses. Upon completion of iterative procedure, was determined the quantity of ion free form and a coefficient of ion association I³e as the ratio of ions free form to its analytical content I³e = Cass/Can. For calculation procedure were used the own software products. The association of ions varies in individual soils and soil layers, Nˆncreasing the soil solution salinity amplifies the ions association. Depending on concentration and composition of soil solution the ionic pairs are: 15-45% Ca2+; 16-49% Mg2+; 0,6-8,4% Na+; 2,2-17,6% HCO3-, 16-51% SO42-, up to 88% CO32-. The proposed thermodynamic calculation method for quantitative assessment of real ion forms in the soil solution helps to explain the evolution of salted soils, maintain the soil, improve plant nutrition and irrigation.

Features of the batch processing technology of aerospace survey data with different spatial resolution are shown to estimate the state of crops from a field to several fields in a selected administrative region. Procedures for the geographical referencing of initial images to land layers are used, as is the classification of remote sensing data while accounting for related crop rotation for the region under study.

Standard and ecologically correct agronomy system of corn based of modern soil processing devices studied. The influence of different soil processing on agrophysical properties and humus content of chernozem common revealed.

Standard and ecologically corrected agricultural practices for a grain corn monoculture on ordinary, calcareous, moderately deep, moderately eroded chernozem with the use of the latest tilling implements are studied. The effect of primary tillage and herbicides Banvel and Milagro on the composition of the agrophytocenose and bioenergy efficiency of agricultural practice is established.

Changes in the properties of solonetzic soil associations (chestnut solonetzic soils and chestnut solonetzes) in the dry steppe after their reclamation have been studied for 30 years. The reclamation included the deep three-tier plowing and the approach of rotary tillage. A single rotary tillage operation resulted in the formation of fine aggregates of equal sizes in the plow layer; any morphological features of the restoration of solonetzic pedogenesis are absent. The atmospheric moisture easily penetrates into the soil, and soluble salts are leached off to a great depth. In 30 years since the soil amelioration with the use of a PMS-70 rotary tiller, the humus content has increased up to 3.3% in the upper 20-cm-thick layer and up to 2.4% in the layer of 20–40 cm. The content of adsorbed Na+ in the 20- to 30-cm-thick layer has decreased to 10.6% of the cation exchange capacity (in comparison with 19.8% in the nonreclaimed soil). The spatial heterogeneity of the soil cover has decreased in comparison with that prior to the reclamation. During the entire observation period, crop yields gained from the fields reclaimed with the use of the rotary tiller have been by 25–60% higher in comparison with those on the fields with traditional treatments.

The thermodynamic calculations were made for the contents of Pb and Cd compounds in soil solutions and water extracts of the meadow-steppe and meadow solonetzes (Rostov oblast) based on their prescribed analytic concentrations of 3 and 5 μg/l, respectively. The solonetzes studied are characterized by their high carbonate content and high alkalinity. The activity of Pb2+ and Cd2+ was shown to be many times lower than their total concentration in the solution due to the association of these metals with carbonate and other anions and the formation of hydroxocomplexes CdOH+ and PbOH+. This fact is one of the reasons for the low input of Pb2+ and Cd2+ to plants growing on calcareous soils.

An effective technology of growing crops with tilling solonetz by a PMS-70 rototiller was developed. On the basis of a long-term field experiment, a 30-year period of influence of cyclic soil ameliorative farming practices of chestnut-solonetz complex soils of the Rostov oblast is substantiated.