Total heavy metal content Descriptive statistics for the heavy metal content of
soils from the study area are shown in Table 2. The mean values of the elements followed the sequence:Fe > Mn > Zn > Cr > Ni > Cu > Pb > Co > Cd. The maximum values followed the same order except for Pb which had a higher maximum value than Ni.The elements Fe, Mn and Zn are considered essential for living organisms. Mean values were 15,274 mg kg-1 for Fe, 320 mg kg-1 for Mn and 57.8 mg kg-1 for Zn. Nickel and Cu are also essential elements and their mean values were 21.6 and 23.7 mg kg-1, respectively.Chromium and Pb are not essential elements for plants and are toxic. Their mean values were 28.3 and 19.6 mg kg-1, respectively.