Abstract: A pot experiment was carried out to investigate the effects of three organic amendments (organic carbon material, rapeseed cake, and pig manure) on the growth and heavy metal uptake of rice on a heavy metal mixed contaminated paddy soil. Applying rapeseed cake and pig manure could mitigate the toxic effect of heavy metals on rice plant. The two organic amendments increased the shoot biomass and grain yield significantly, and decreased the heavy metal concentration in brown rice. Under the application of organic carbon material, rice growth was inhibited. As compared with the control, applying rapeseed cake and pig manure increased the grain yield by 1283% and 679%, and decreased the Cd, Cu, and Zn concentrations in brown rice by 476%, 352% and 215%, and 95%, 212% and 93%, respectively. The shoot biomass and its total accumulation of Cd, Cu, and Zn had significant negative correlations with the soil DTPA-extractable heavy metals.

Key words: organic amendment, rice, zinc, cadmium, soil