PCA analysis and Concentration of Heavy Metal in the Soil, Guangdong, China

The concentrations of 9 metals (Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn) in topsoil in Guangdong were investigated based on 261 samples. Principal component analysis (PCA) was applied to the data matrix to evaluate the analytical results and to identify the possible sources of metals. The average concentrations (mg/kg) obtained were: Cu 17.37 mg/kg, Ni 17.7 mg/kg, Cr 56.7 mg/kg, Co 6.83 mg/kg, Mn 223.16 mg/kg, Pb 36.63 mg/kg, Hg 0.10 mg/kg, Cd 0.09 mg/kg and Zn 49.75 mg/kg. The results of factor analysis group Pb, Zn, Cd, Hg and Mn in F1 and Cu, Ni, Cr, Co in F2. The spatial heavy metals component maps show definite association of these factors with the soil parent material and soil types. The concentration levels are relatively low in areas of high pH and low organic matter content concentration. The 9 metals in Guangdong have generally low concentrations and distinct geographical patterns. The local anomalies (found in Cu, Zn and Pb) are attributed to anthropogenic influence.