GEOSPATIAL MAPPING OF ECOLOGICAL RISK FROM POTENTIALLY TOXIC ELEMENTS IN SOIL IN THE PANNONIAN-CARPATHIAN BORDER AREA SOUTH OF THE DANUBE

Abstract

This study collected agricultural surface soil samples from 200 sites in the district of Braničevo, located in the Carpathian Mountains – Pannonian Basin south of the Danube River (Serbia). The main objective was to determine the soil contamination by ten potentially toxic elements (As, B, Cd, Cr, Cu, Mn, Mo, Ni, Pb, Zn) and evaluate the associated ecological risk via different indices. The physicochemical parameters, pH, organic carbon, water content, and soil texture were also analyzed. The mean values of most metal concentrations remained below their corresponding national target values, except for Mo and Ni. The main soil texture types were silt loam (40.5 %) and silty clay loam (34.5 %). According to the mean values, pollution load index (PLI) and potential ecological risk (RI) demonstrated that the soil in the study area was exposed to moderate pollution and moderate ecological risk, while enrichment factor (EF), geoaccumulation index (Igeo), and contamination factor (CF) revealed very high enrichment and contamination with Mo, implying the impact of anthropogenic activities. There was a lack of strong correlations among elements and soil properties, except for Cd and Corg, while moderate to strong positive inter-metal relationships suggested their common sources. The chemometric analysis illustrated the classification of sampling sites into two distinct clusters of spatial similarities according to higher and lower metal concentrations. Geospatial mapping identified a few areas of considerable ecological risk.