GAO Yang, XU Dongsheng, LI Qi

（School of Environment and Surveying Engineering, Suzhou University, Suzhou 234000, China）

Abstract: The environmental geochemical baseline is an indicator for discriminating natural and anthropogenic environmental hazardous substances, and to establish environmental geochemical baselines in the particular area is of important practical significance and reference value. This study analyzed total contents of six heavy metals (Cu, Zn, Pb, As, Cr and V) in surface soils of Suzhou City, estimated their environmental geochemical baselines using the normalization approach and the relative cumulative frequency method, and evaluated their pollution status using the cumulative geochemical index and the obtained geochemical baselines. The results showed that the average contents of Cu, Zn, Pb, As, Cr and V in surface soils were 18.29, 52.61, 20.84, 10.29, 69.83 and 82.27 mg/kg, respectively, and that their environmental geochemical baselines were 16.97, 48.66, 19.43, 9.07, 65.22 and 79.08 mg/kg, respectively, which were in accordance with the definition and practical significance of these heavy metals. The results indicated that the six heavy metals in the most surface soils of Suzhou were at uncontaminated level, only few showed moderate contaminated level, and that no enrichment or depletion trend of six heavy metals was found in surface soils of Suzhou.

Key words: soil; heavy metal; environmental geochemical baseline; cumulative index of geology; Suzhou city

EARTH AND ENVIRONMENT Vol.46, No.5, Tot No.325, 2018, Page 444-450