Biomonitoring of Trace Element in Air and Soil Pollution by Using Acacia

Effects of soil and atmosphere pollution on some heavy metals (Fe, Zn, Pb, Cu, Mn and Cd) concentration in Acacia (Robinia psudo acacia L.) leaves were studied in the city of Isfahan, Iran. Samples were collected from four sampling sites representing area of high traffic density, light traffic area near the city, industrial area and one village far from pollution source as a control. Samples were collected in two seasons (June and September) in 2010 for chemical analysis. Based on the results, the collection time of leaf sampling did not showed any significant effects on concentration of the measured heavy metals in leaf samples. Chemical analyses of soil samples at depth of 0-10cm showed that concentration of these elements in most cases were lower than the maximum recommended levels. Lower concentrations of all measured heavy metals were found in washed leaves in comparing with unwashed ones. In spite of that, there was no significant correlation between the concentrations of heavy metals in washed leaves and in soil samples. Results of this investigation showed that the industry and traffic were the main source of air pollution in Isfahan, and acacia tree is a dependable biomonitor for air and soil pollution investigations.