『Abstract
　Fractionation of heavy metals (HMs) in amended soils is needed to predict elemental mobility in soil and phytoavailability to plants. A study was conducted to determine the effects of different amendments on HMs availability and their redistribution among soil fractions. A contaminated with 0, 2, 4, and 6 g kg^-1 of vermicompost (VC), zeolite (ZE), and di-ammonium phosphate (DP) and incubated at field moisture. The amounts of Cd, Pb, Zn, and Cu were determined from the soil after 6 months of incubation time using DTPA and sequential extraction procedures. The total concentrations of Cd, Pb, Zn, and Cu were 41, 3,099, 1,997, and 83 mg kg^-1 of soil, respectively. All amendments decreased significantly [probability (p)≦0.05] DTPA-extractable Cd, Pb, and Cu, but not Zn, in the soil. For instance, DTPA-extractable Cd, Pb, and Cu decreased by 40, 290, and 20％, respectively, and that of Zn increased by 18％ with DP1 (2 g kg^-1 of di-ammonium phosphate) application. The concentrations of Pb and Cd decreased mainly in the specifically sorbed (SS) but increased in the amorphous Fe oxide (AFeO) fraction with DP application, indicating redistribution of Pb and Cd in the fractions with less mobility. Lead immobilization by DP was mainly attributed to the P-induced formation of chloro-pyromorphite, which was identified in the DP treatment using X-ray diffraction technique. It was concluded that DP was the most effective amendment in immobilizing Pb and Cd, though it increased Zn mobility.

Keywords: Immobilization; Heavy metals; Vermicompost; Zeolite; Phosphate』

Introduction
Materials and methods
Results and discussion
　Soil pH and EC
　Soil Cd
　Soil Pb
　Soil Zn
　Soil Cu
Conclusion
Acknowledgments
References