Assessment of the Ecological Status and Technogenic Contamination of Uzhhorod Urban Soils With Mobile Forms of Heavy Metals

The publication presents a geochemical assessment of the ecological status and technogenic contamination of urban soils (urbanozems) in Uzhhorod with mobile, bioavailable forms of heavy metals, including iron (Fe), copper (Cu), lead (Pb), cadmium (Cd), manganese (Mn), nickel (Ni), and zinc (Zn). Soil samples were collected across functionally contrasting locations—a recreational zone in the Botanical Garden and high-traffic urban thoroughfares—and analyzed via acetate-ammonium buffer extraction (pH 4.8–5.0) followed by atomic absorption spectrometry, with concentrations verified against Ukrainian maximum permissible concentrations (MPCs). The findings reveal pronounced spatial differentiation in ecotoxicant distribution governed by traffic intensity and land use, identifying critical chronic exceedances of sanitary limits for mobile cadmium (by 2.0–3.6 times) and nickel (by 2.1–3.0 times) in the traffic-urbanized sector due to vehicle congestion and diesel emissions.

Localized hotspots of excessive zinc accumulation were also recorded along major highways as a consequence of tire wear and galvanized infrastructure corrosion, whereas mobile copper remains diffusely distributed within regional geochemical background levels. While lead levels generally balance near threshold limits across most urban monitoring sites, a localized natural-anthropogenic anomaly exceeding the MPC by 1.8 times was detected in an isolated section of the Botanical Garden, correlating with elevated mobile iron and manganese mobility driven by lithological heterogeneity, local acidification, and reductive hydrological processes. Overall, the study demonstrates intense multi-element vehicular pressure on Uzhhorod urbanozems and substantiates the necessity for detailed micro-zonal investigations of substrate acid-base and particle-size properties.