Evaluating of heavy metal pollution in Amir-Kalayeh wetland using geochemical and statistical analyses

Abstract

Metal pollution in aquatic ecosystems has created concern due to its toxicity, environmental stability and ability to transfer into the food chain, and monitoring the metal source is one way to decrease the environmental impact. The present study aimed to investigate metal concentrations of Al, Fe, Mg, P, As, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, V and Zn, their spatial distribution, origin of the contaminants, contamination factor (CF), pollution load index (PLI), enrichment factor (EF), and geoaccumulation index (Igeo) in surface sediments of the Amir-Kalayeh wetland. Using statistical methods such as Pearson correlation coefficient, cluster analysis and factor analysis, the natural or anthropogenic origin of these elements was determined. According to the results, As, Cd, Mn, Mo And Pb have CFs higher than 1, which means they have contaminated the area. In this research, PLI was 0.9, which means the sediments of Amir-Kalayeh wetland are not polluted. The highest EF belongs to Mn and Mo. Determining Igeo showed that none of the metals in Amir-Kalayeh wetland are within the pollution range. However, the enrichment of elements in the sediments shows that continuous monitoring and managing of metal pollution source in this wetland is an essential step.