Determination of geochemical baseline and pollution enrichment of soil heavy metals in suburb of Suzhou City

To investigate the enrichment of soil heavy metals, 50 soil samples were collected and the contents of V, Cr, Zn, Pb, Cu and As were measured by X-ray fluorescence spectrometer. The environmental geochemical baseline values of heavy metals are determined by standardized methods, and the pollution and enrichment degrees of heavy metals are evaluated based on geoaccumulation index method and enrichment factor method. The results show that the contents of V, Cr, Cu, Zn, Pb and As vary widely with the mean values of 81.32, 65.54, 17.16, 49.28, 20.04 and 11.68 mg·kg−1, respectively. Among them, except for As, the average values of the other 5 elements are lower than the soil background values of Anhui Province. The results of the standard reference method indicate that the 6 heavy metal elements have a strong correlation with Fe, and the baseline values of heavy metals are 81.33, 65.56, 17.18, 49.29, 20.04 and 11.67 mg·kg−1, respectively. The mean values of I geo for the 6 heavy metals are less than 0, indicating that there is no pollution of heavy metals in the soil of Suzhou. The average enrichment factor is greater than 1, with slight enrichment, and the interference of human activities on soil heavy metals not obvious.