Spatial analysis of heavy metals in surface soil, NW Iran

During last decade, drying of Lake Urmia and salty dust emission could be contaminated soil in northwest of Iran. This study aimed to assess the concentration and spatial analysis of toxic metals (As, Cd, Cu, Ni, Pb and Zn)in surface soils. Soil samples were taken from the top 30 cm of soil and analysed for heavy metals content using inductively coupled plasma optical emission spectrometry (ICP-OES). As results of Moran's I model, distribution pattern for As, Cd, Cu, Ni, Pb and Zn were random (z-score ranged between -1.17 and 1.09). Indicated that these elements could be emitted from different potential sources. Spatial analysis shows that Cd, Cu, Pb, Ni, and Zn, have similar distribution trends with non-identical values which indicated that their sources could be identical. Based on degree of contamination (C-deg) index, soil samples from north, northwest and northeast were categorised at very strong contamination degree. Finally, in northwest of Iran, drying Lake Urmia, agricultural and industry activity could be lead to soil and air pollution in terms of heavy metals.