MONITORING OF LEAD CONTENT IN AGROECOSYSTEMS OF CENTRAL BLACK EARTH REGION OF RUSSIA

Studies on the environmental assessment of Pb content in agroecosystems were carried out in the forest-steppe zone of the Belgorod region, which is located in the south-west of the Central Black Earth region. The soil cover was represented mainly by leached chernozems. As a result of studies, it was established that in the layer of 0–20 cm of arable soils, the average gross content of Pb is 13.1, the concentration of mobile forms is 1.09 mg/kg, which does not exceed the background values and is significantly lower than the levels of APC and MAC. There were no significant differences in the content of Pb in the soil layers of 0–20 and 21–40 centimeters. The excess of background concentrations of this element is established in the soils of roadside ecosystems. The main source of Pb supply to the agroecosystems of the Belgorod region is organic fertilizers, but this does not pose a danger to soil pollution and crop production. The average Pb content of corn, barley and winter wheat grains did not differ significantly and was 0.267, 0.275, 0.292 mg/kg, respectively. Of the studied cultures, the minimum amount of this element was contained in soybean grains (0.155 mg/kg), and the maximum amount in sunflower seeds (0.335 mg/kg). Of perennial legumes, the minimum amount of Pb was contained in clover hay (0.185 mg/kg), and the maximum amount was esparceta (0.344 mg/kg). Exceeding the levels of the maximum permissible concentration and the maximum permissible level of Pb in crop production was not detected.