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The distilled water was exposed to a cold atmospheric plasma (CAP) generated by the piezotransformer. The treatment was carried out on a six-well plate. Exposure time was from 30 s to 10 min. The emission spectra were obtained. Physical and chemical changes of activated water were observed for 8 days. The reactive oxygen and nitrogen species (RONS) were investigated. RONS production dependence on the exposure time and RONS lifetime in the treated liquid was determined using absorbance spectra. Quantitative assessment was made of the nitrite and nitrate concentration change over time after treatment. The medium conductivity and redox potential varied linearly depending on exposure time. The pH value change correlates with nitrate anion concentration. The concentration of peroxide hydrogen increased depending on CAP water treatment duration. The RONS concentration after liquid media processing with piezoelectric direct discharge CAP is a novel result. Biogeosystem Technique provides CAP activated water agriculture synergetic effect.

The Kastanozem complex in the dry steppe of southern Russia underlies an artificially-constructed forest strips. Deep ploughing to a depth of 45 cm was used to process the soil prior to planting. Between 20 and 40 cm depth, soil density was high, 1.57 t m−3. Soil hardness was also high, 440 psi. Soil aggregates greater than 5 cm in size were impermeable to tree roots. The content of such aggregates was high, comprising 35%. The number of tree roots with diameters greater than 0.5 cm that cross the soil profile was as low as 0.15 to 0.3 pcs cm−2. The soil matric potential signifying water availability was low in the vegetation period −0.9 MPa to a depth of 1.0 m. According to modelling experiments, the main salt components in the soil solution drive the transfer of soil organic matter (SOM) and heavy metals (HM). The composition of the soil solution determined by the calcium carbonate equilibrium (CCE) and the association and complexation of ions. ION-3 software was used to calculate the ion equilibrium in the soil solution. Macro-ions Cа2+, Mg2+, SO42−, and CO32− partly bonded as ion pairs. Oversaturation of the soil solution with CaCO3 was calculated according to the analytical content of macro-ion, which was high up to 1000 units, and its value decreased in response to ionic strength, activity, association, complexation, and thermodynamic equilibrium of macro-ions in the soil solution. Oversaturation calculated for Salic Solonetz and Gleyic Solonetz soil solutions was small considering the SOM content. Calculations indicate the profile and lateral loss of C from the soil to the vadose zone. The content of Pb in the soil solution was calculated sirca 75%–80%. The calculated coefficient of Pb2+ association was as high as 52.0. The probability of Pb passivation by SOM in the Kastanozem complex was significant. The probability of uncontrolled transfer and accumulation of HM in the soil and vadose zone was high. Biogeosystem Technique (BGT*) transcendental methodology, an innovative methodology created for stable geomorphological system formation to achieve sustainable agriculture and silviculture, was applied. The BGT* elements were: intra-soil milling of the 30–60 cm soil layer for geophysical conditioning; intra-soil continuously-discrete pulse watering for plants and trees to improve the hydrologic regime. The BGT* methodology reduced HM mobility, controlled biodegradation, enriched nutrient biogeochemical cycling, increased C content, increased soil productivity, and reversible carbon sequester in biological form.

Stabilization mechanisms of easily and poorly soluble Zn compounds in Haplic Chernozem are considered in a long-term incubation experiment, including the dissolution and hydrolysis of the Zn added compounds (acetate, nitrate, sulphate, chloride, phosphate, and oxide) at a rate of 300 and 2000 mg kg –1 and the following post-sorption metal transformation. The indicators of stabilization were changes in the content of Zn weakly bound compounds (WBCs) and soil pH. Stabilization of Zn acetate, nitrate, sulphate, chloride progressed during incubation for 5 years which resulted in a decrease of Zn WBCs and an increase in soil pH. In the soil contaminated with Zn phosphate and oxide, the content of Zn WBCs increased and the soil pH decreased with time.

The thermodynamics has been studied of Pb forms in soil solution for the case of calcareous ordinary chernozem of the Southern Russia, northern zone of the Krasnodar krai for conditions of phosphogypsum utilization into the soil layer of 20–40 cm at doses of 0, 10, 20, and 40 t ha− 1. The application of phosphogypsum increased the contents of total Pb by 4.2; the content of water-soluble forms – by 17.7. As a result of ion association in soil solution are presented electrically neutral ion pairs СаСО30; CaSO40, MgCO30, MgSO40, and charged ion pairs CaHCO3+, MgHCO3+, NaCO3−, NaSO4−, CaOH+, MgOH+. The contents of soluble Pb2 + forms in water extracts were calculated by mathematical chemical-thermodynamic model of ion pairs association in soil solution using algorithm and computer program ION-2. The coefficient of heavy metal ion association kas in soil solution is proposed for calculation of the heavy metal equilibrium concentration in soil solution. The model shows that calculated association coefficient of Pb2 + is up to 25.0, Pb2 + is presented mostly in the form of PbOH+ and Pb(OH)20. The quantity of PbCO30 + Pb(CO3)22 − and PbHCO3+ is lower than content of hydroxide-complexes by 10–15 times. At the phosphogypsum dose of 40 t ha− 1, the association coefficient of Pb2 + ion decreases by 2.0 times comparing to initial soil, and its activity increases by 60.0%. The molar fraction of hydroxo complexes decrease for 4.0, carbonate for 5.0, and sulfate associates – increase for 4.5%. The dangerous increase of activity of Pb2 + ion in soil solution after phosphogypsum apply up to 90.0% of its concentration is revealed.

The long-term field experiment on the Kastanozem showed that the standard moldboard plowing to a depth of 22 cm (control), chiseling to a depth of 35 cm, and three-tier plowing (machine type PTN–40) to a depth of 45 cm was incapable of providing a stable soil structure and aggregate system. The transcendental Biogeosystem Technique (BGT*) methodology for intra-soil milling of the 20–45 cm layer and the intra-soil milling PMS–70 machine were developed. The PMS–70 soil processing provided the content of 1–3 mm sized aggregate particle fraction in the illuvial horizon of about 50 to 60%, which was 3-fold higher compared to standard plowing systems. Soil bulk density reduced in the layer 20–40 cm to 1.35 t m−3 compared to 1.51 t m−3 in the control option. In the control, the rhizosphere developed only in the soil upper layer. There were 1.3 roots per cm−2 in 0–20 cm, and 0.2 roots per cm−2 in 20–40 cm. The rhizosphere spreads only through the soil crevices after chilling. After three-tier plowing (PTN–40), the rhizosphere developed better in the local comfort zones of the soil profile between soil blocks impermeable for roots. After intra-soil milling PMS–70, the rhizosphere developed uniformly in the whole soil profile: 2.2 roots per cm−2 in 0–20 cm, 1.7 roots per cm−2 in 20–40 cm. Matric water potential was higher, soil salinization was lower, and the pH was close to neutral. Soil organic matter (SOM) content increased to 3.3% in 0–20 cm and 2.1% in 20–40 cm compared to the control (2.0% in the 0–20 cm soil layer and 1.3% in the 20–40 cm layer). The spring barley yield was 53% higher compared to the control. The technology life cycle profitability was moldboard 21.5%, chiseling 6.9%, three-tier 15.6%, and intra-soil milling 45.6%. The new design of the intra-soil milling machine provides five times less traction resistance and 80% increased reliability, halving energy costs.