Assessment and prioritization of different land use effect on surface soils contamination with some trace elements in Rey City, Tehran Province, Iran

Assessment of different land use effects on surface soil contamination is necessary for sustainable management of urban-industrial ecosystem.for this purpose in Rey city of Tehran province ,soil sampling was conducted across industrial and other land-use areas, collecting 52 composite surface samples (0–20 cm depth) to assess trace metal contamination. Samples were analyzed for metals (As, Cd, Pb, Zn, Cu, Ni) using atomic absorption spectrophotometry (AAS) and inductively coupled plasma (ICP-OES). Physical and chemical properties (texture, pH, organic matter, calcium carbonate) were measured via standardized methods.Pollution levels were evaluated using indices like the geoaccumulation index (Igeo), contamination factor (CF), Nemerow pollution index (NIPI), and potential ecological risk index (PERI), which incorporated toxicity factors and background values. Spatial hot/cold spots of contamination were identified via Getis-Ord analysis, highlighting clusters of high/low metal concentrations. These methods aimed to distinguish natural versus anthropogenic contamination and assess ecological risks. The study emphasized integrating geochemical, statistical, and spatial tools to map pollution patterns and prioritize mitigation efforts in Rey City’s industrially impacted soils. The Getis-Ord analysis revealed minimal pollution for Al (12% cold spots), localized As (<5%) and Cd hot spots, and elevated contamination for Cu (13%), Hg (>50% in west/north), and Mn. Mercury and manganese exhibited the most widespread pollution, highlighting critical environmental risks in Ray City, while aluminum showed negligible contamination. The results provide valuable guidance for policymakers, urban planners, and environmental managers to design targeted remediation efforts and preventive measures to reduce soil pollution risks.