Assessment of Zinc Content in Agroecosystems of the Central Chernozem Region of Russia

Studies were conducted in 2005–2024 in the forest-steppe zone of the Central Chernozem Region in the Belgorod and Voronezh regions where the soil cover is mainly represented by Haplic Chernozems and Luvic Chernozems. The purpose of the work was to conduct an agroecological assessment of zinc content in arable soils, fertilizers, and agricultural plants. During the research, based on local monitoring data, it was established that in the arable layer of chernozems the average content of acid-soluble forms of zinc is within 36.1–36.5 mg/kg. The results of continuous agroecological monitoring for the eighth and tenth cycles indicate that the weighted average content of mobile forms of zinc in the soils of the Belgorod Oblast is consistently low (0.50 mg/kg), and in the soils of the Voronezh Oblast it has decreased from 0.45 to 0.30 mg/kg. The low supply of mobile forms of zinc to arable soils is a significant factor limiting the productivity of agroecosystems. To eliminate the deficiency of this element, it is necessary to incorporate the use of microfertilizers in the technology of cultivation. Soils of roadside agroecosystems tend to accumulate this element. An important source of zinc in soils are organic fertilizers, especially in the Belgorod Oblast, where the average application doses reached 9.6 t/ha. The average zinc content in hay of perennial legumes was within 14.0–17.8; it was 26.5 to 43.5 in the main products of leguminous crops, and 17.6 to 28.6 mg/kg in grain crops. In sunflower seeds, the content of the element was 41.1, and in sugar beet roots it was 9.2 mg/kg. No exceedances of maximum permissible zinc concentrations in soils (including roadside agroecosystems) or maximum permissible levels of its content in feed products were recorded.