The effect of oven drying and grinding on the partitioning of copper and nickel in acid sulfate soil materials

摘要

A sequential extraction procedure was applied to an acid sulfate soil profile to investigate the effect of sample preparation on the partitioning of copper and nickel. The samples were either used as collected (field condition) or subjected to the standard sample preparation, commonly applied to soils to be stored for subsequent analysis (i.e. oven drying and grinding). This effect was investigated both in the oxidised zone and unoxidised zones of the soil profile. Both sets of samples (i.e. oxidisedand reduced) showed a substantial loss in the HNO_3-extractable fraction in the dried and ground soil materials, and in the reduced materials there was with a corresponding increase in the copper and nickel recovered in the MgCl_2 and HC1 fractions. Based on these findings, it is recommended that when assessing metal partitioning, acid sulfate soil samples be analysed in their field condition.