Geochemical and anthropogenic factors of variability of heavy metals content in the soils and crops of Ukraine at the example of copper

Abstract

Nowadays, anthropogenic inflow of heavy metals (HM) into the environment far exceeds their natural quantities in Ukraine. The main sources of HM inflow are enterprises that use high-temperature processes in the production cycle-combustion of fuel and thermal processing of raw materials. Examples of such enterprises are Avdiivka Coke and Chemical Plant (the largest in Europe) and the Zmiiv Thermal Power Plant (the largest in Ukraine), which use high-temperature processes associated with the use of black coal that are considered as important sources of heavy metals in the soil. On the basis of analytical data of 3000 samples of surface layer of Ukrainian soils, which form the basis of the nationwide GIS "Microelements in soils of Ukraine," it was established that the spatial distribution of the content of accessible forms of copper in the upper soil layer in Ukraine varies greatly and practically does not depend on the type of soil formation and is determined mainly by geochemical factors such as saturation of parent rocks with copper, as well as anthropogenic influence. The emissions from the Avdiivka Coke and Chemical Plant resulted in the formation of a clearly defined contamination range of soil and vegetation by HM in the adjoining territories exceeding the threshold levels of copper. In the zone of influence of the Zmiiv Thermal Power Plant, the technogenic load on agricultural lands is much less and does not exceed the medical and sanitary indicators of the content of heavy metals in the soils, but due to the high pipe height (180-250m), the toxic emissions of the enterprise dissipate to a large area and form a regional technogenic background of available copper in soils.