Abstract: Effects of treatment and storage methods, including refrigerating, freezing, freezedrying, oven drying and air-drying on the partitioning patterns of metals in surficial sediments, were investigated through the modified sequential extraction procedure. The results showed that there were different affections for the partitioning patterns of Fe, Mn, Cu, Zn and Pb by the five methods, and the effect of the five methods on partitioning pattern of Fe (<3.3%) was found lowest among the metals of Fe, Mn, Cu, Zn and Pb, and Mn the highest (up to 10.2%);The lowest effect of the methods on partitioning patterns of all the metals was the freeze-drying (<4.6%). It was also observed that the effects of oven drying and air-drying on distribution of Cu, Zn and Pb in exchangeable fractions (Ⅰ+Ⅱ) or non-residual fractions (Ⅰ-Ⅴ) were higher compared to the other three treatment methods. Thus, it was concluded that the method of freeze-drying was the most suitable treatment and storage method while investigating the partitioning pattern and bioavailability of metals in surficial sediments.

Key words: surficial sediments, metal speciation, freeze-drying, bioavailability