A Study of Baseline Values for Copper and Lead in Four Subtypes of Surface Soils in Hohhot City, China

摘要

The baseline values of Copper (Cu) and Lead(Pb) in four subtypes of soil in Hohhot, Inner Mongolia in China were proposed by testing the Cu and Pb contents in surface soils over an area of 4713km~2. The soil subtypes were distinguished by GIS (Geographic Information System) and the 928 sample locations were roughly uniformly distributed using portable GPS (Global Positioning System).The proposed baseline values of Cu and Pb were derived from the experimental results of ICP-MS analyses and then were calculated by probability density function. The results illustrate that the baseline value of Cu in the Fluvo--aquic Soil was the highest(18.83 mg kg~(-1)),and that Pb in Diluvial Alluvial Topsoil was the highest (17.50 mg kg~(-1)),which are far lower than the corresponding Class One thresholds in Environmental Quality Standard for Soils in China (GB15618-1995) (EQSSC).This experience gained in this work further suggests that baseline values should be proposed in other areas in the world.