Heavy metal content of soil in urban parks of Belgrade

This study focuses on soil pollution in four urban parks of Belgrade. The sampling locations within each park were chosen based on proximity to streets characterized by heavy traffic, and soil samples were taken at different depths down to 50 cm. Concentrations of six heavy metals (Cr, Cu, Fe, Mn, Ni and Zn) were measured using Energy Dispersive X-Ray Fluorescence (EDXRF) spectrometer. The following average abundance order of heavy metals was found: Fe >> Mn > Zn > Cr > Ni > Cu in topsoil samples. The highest enrichment in topsoil was observed for Zn. Copper and Zn, metals mainly related to traffic emissions, exhibited the highest concentrations at the sampling location close to a bus and trolleybus termini. The highest Ni and Cr concentrations were observed in a park located in a city suburb, where a large number of individual heating units is present. The largest decrease in concentrations with soil dept was observed for Zn and Cu, followed by Ni and Cr, in the parks with the highest concentrations of these elements in topsoil. Generally high topsoil Cr and Ni concentrations were observed in comparison with average values reported in literature for other world cities.