CONTAMINATION AND ECOLOGICAL RISK ASSESSMENT OF HEAVY METALS IN AGRICULTURAL SOILS IN PLJEVLJA MUNICIPALITY (NORTH MONTENEGRO)

Quantification of soil enrichment by heavy metals (As, Hg, Cd, Pb, Cu, Zn and Cr) in Pljevlja ( Montenegro) was evaluated using different pollution indices (contamination factor (Cf), degree of contamination (Cd), enrichment factor (E-f), index of geo-accumulation (I-geo), ecological risk factor (E-r), ecological risk index (RI) and pollution index (PLI). Descending order of mean values of heavy metals concentrations was found as follow Zn >Pb> Cu > Cr > As > Cd > Hg. The assessment study revealed some hot spots for Cd, Pb, Cu and Zn since pollution indices of these metals indicated moderate to high contamination of soil. Values of C-f, I-geo, E-r and RI suggested that Cd is the pollutant of highest interest in agricultural soils in Pljevlja municipality among all the analysed metals. Afterwards, Pb follows in pollutant ranking since values of C-f and I-geo, for Pb indicated soil contamination by this metal. Pearson's correlation coefficient analysis was applied to identify associations between heavy metals. A significant positive correlation was found between Pb, Zn and Cu, while a moderate positive correlation was found between Cr and Cd, and As, Cu, Zn. PCA analysis in two-dimensional space was in correlation with Pearson's correlation coefficient since Pb, Zn, Cu, As belong to PC1 and are considered to be from the same anthropogenic source.