Lead (Pb) is a widespread pollutant presented in soil, by various compounds. However, only mobile forms represent a danger to living organisms. The mobile compounds are those extracted with 0.1 and 1.0 HCl. Soil indexes likethe content of particles less than 0.001 mm (clay), soil organic matter (SOM) content, pH status of the soil solution significantly affect the mobility of lead. Application of mineral and organic fertilizers can enhance or reduce the mobility of lead in soil as well. The influence of fertilizers on the mobility of lead, as well as the peculiarities of its translocation into plants, was investigated at long-term-field experiments in three main climatic zones of Ukraine (Polissya, Forest-steppe, Steppe). We found that the soil parameters had the influence on lead mobility were in the following sequence: clay content> SOM > soil рН. There was a strong inverse correlation between lead mobility and soil parameters (r = 0.821-0.962). Application of mineral fertilizers increased the content of lead mobile forms in soil (by 7-24%), whereas organic fertilizers contributed to its decrease. Crops were ranged by the ability for lead accumulation in the following order: clover> sugar beets > corn> sunflower> winter wheat. Furthermore, mineral fertilizers contributed significantly to lead translocation from the soil to crops, while the influence of organic fertilizers on this process was insignificant.

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Zinc (Zn) deficiency is the most common problem of micronutrient deficiency on our planet. This problem is also relevant for Ukraine, as soils are insufficiently provided with Zn, plants are deficient, respectively, and insufficient quantity of Zn is contained in food, which leads to human diseases. Our research showed that the total zinc content in soils increased from the north to the south of Ukraine (Polissya ˂ Forest-Steppe ˂ Steppe): in sod-podzolic soil the Zn content was 40 mg kg -1 , in dark gray podzolic -45 mg kg -1 , chernozem typical -48 mg kg -1 , chernozem ordinary -58 mg kg -1 , dark chestnut -70 mg kg -1 . The content of Zn mobile forms, on the contrary, was subject to inverse dependence -the highest level was observed in the soils of Polissya -9.5 mg kg -1 , the lowest in the soils of Steppe -0.5 mg kg -1 . Zn was more firmly fixed by the soils of chernozem-type, higher mobility was observed in soils with pronounced podzolic processes. Zn mobility depended from the properties of soil: pH of the soil solution, the amount of organic matter and clay minerals. Zn mobility increased with increasing soil acidity, increasing the amount of organic matter and clay fraction. There was a close inverse correlation between these indicators and Zn mobility: the pairwise correlation coefficients (r) ranged from -0.861 to -0.991. Agrotechnological methods of winter wheat growing reduced the quantity of potentially mobile Zn compounds in the soils of Polissya, Forest-Steppe and Steppe of Ukraine in compared to the natural background. However, mineral and organic fertilizers mainly increased their content, as well as intensified the transfer of Zn from the soil to wheat plants, as evidenced by the biological absorption coefficients which were ˃ 1.