Ecological Assessment of the Content of Cadmium in Soils and Crops in Southwestern Regions of the Central Chernozemic Zone, Russia

Abstract

It is found that in Belgorod oblast during 2010–2014, cadmium mainly came into agrocenoses with organic fertilizers (0.4 g/ha, or 73.9%) and ameliorants (0.116 g/ha, or 21.4%). The lowest total content of cadmium in the A horizon (0.22 mg/kg) was noted in meadow-chernozemic soil (Greyzemic Stagnic Chernic Phaeozem (Clayic, Pachic)) developed on old alluvial calcareous deposits, and its highest content (0.42 mg/kg) was found in ordinary chernozem (Haplic Chernozem (Clayic, Pachic)), where loess-like clay is the main parent rock. Virgin leached chernozem (Luvic Сhernozem (Loamic, Pachic)) formed on loess-like loam, contained 0.33 mg Cd/kg in the A horizon, which almost coincided with the mean content of this element (0.32 mg/kg) in the plow layer of leached chernozems on reference plots. No exceeding of the tentative permissible concentration of cadmium was revealed in arable soils. In crops, the content of cadmium was highest in sunflower seeds (0.086 mg/kg) and soya beans (0.072 mg/kg), and lowest in peas (0.032 mg/kg) and white lupine beans (0.013 mg/kg). The biological adsorption factor varied within the range from 0.97 (while lupine beans) to 10.8 (sunflower seeds) for target agricultural crops and from 0.41 (while lupine straw) to 4.63 (soya straw) for side products.