Аннотация:Abstract—In Russia, the area of oil-contaminated soils exceeds tens of thousands of hectares. However, to date, there are no unified approaches for evaluation soil pollution and the rationing of oil and petroleum hydrocarbons (PHs) in soils. The response of plants in the pot experiment could provide significant results for rationing of PH content in agricultural soils. This work evaluates the response of higher plants as a markerof the direction and intensity of biological processes in soils in the pot experiment under oil contamination to justify the standards of permissible residual content of PH in agricultural soils. The composition and properties of Luvic chernozems, Calcic chernozems, and Voronic chernozems (WRB, 2015) have been investigated in the pot experiment a month later the soil contamination with crude sulfur-containing oil. The effect of different oil doses on the bioproductivity of wheat and pea has been evaluated. In comparison to pea, wheat(in terms of dry biomass) showed higher sensitivity to oil contamination with medium and heavy PH fractions. A nonlinear regression model described by a logistic curve has been applied for rationing the PH content in chernozems. The quality standard values found for wheat biomass are 0.9, 0.4, and 1.0 g/kg of soil forLuvic (humus content ~9.8%, sandy loam texture), Calcic (humus content ~7.6%, clay loam texture), and Voronic (humus content ~12.8%, loam texture) chernozems, respectively. The residual PH content levels found as 30% of soil-functioning change, which corresponded to the risk level of soil degradation, estimated by the soil fertility parameter of dry wheat biomass are 1.2, 0.5, and 1.1 g/kg for Voronic, Calcic, and Luvicchernozems, respectively
