The content of heavy metals and arsenic in soils and plants of the forest-steppe of Western Siberia

The purpose of the research is to identify the level and patterns of changes in the content of heavy metals and arsenic in arable soils and forest-steppe products of the Omsk region. Monitoring data for 1994-2018 on reference plots laid on arable soils are analyzed. Objects of research: cultivated plants and soils (low-power medium-humus heavy-loam segregated agrochernozem, medium-thick quasi-clay high-humus heavy-loam agrochernozem, hydrometamorphosed deep light-loam agrochernozem). The total content of copper, nickel, chromium is at the same level regardless of the horizon, arsenic-increases with depth, and cadmium, lead and mercury-decreases, as well as zinc (except for segregated agrochernozem, where its concentration decreases with depth, but then the opposite trend is observed). In the arable horizon, the content of heavy mobile metals varied within the following limits (mg/kg): in agrocenoses segregation of low-power srednekraevom loam: copper - 0.12-0.15; zinc - 0.37-0.49; cadmium - 0.06-0.08; lead - 0,62-0.71; nickel - 0,52-0.69; chrome - 0.29-0.68; in low-power medium-humus heavy-loam segregated agrochernozem: copper - 0.11-0.14; zinc - 0.39-0.59; cadmium - 0.06-0.07; lead - 0.67-0.79; nickel - 0.62-0.70; chrome 0.50-0.94; in hydrometamorphosed deep light-oam agrochernozem: copper - 0.11-0.14; zinc - 0.32-0.41; cadmium - 0.06-0.09; lead - 0.58-0.64; nickel - 0.57-0.70; chromium - 0.54-0.70. The studies also determined the total content of mercury and arsenic in soils, exceeding the maximum permissible concentrations were not found. Monitoring of the content of heavy metals and arsenic in crop samples revealed that agricultural products obtained at reference sites, both main and secondary, meet agroecological requirements. The content of copper was 1.9-4.3 mg/kg; zinc - 6.2-23.8; cadmium - 0.027-0.100; lead - 0.28-1.11 mg/kg; and mercury and arsenic - did not exceed the minimum level of determination of these indicators on the devices.