Abstract:Pot experiment was conducted to study the tolerance and remediation effect of Napier grass to cadmium (Cd) in purple soil and granitic sandy soil using Fourier infrared and X-ray diffraction analysis methods, and the exogenous Cd was added with gradients of 0, 0.5, 2.0, 10.0, 20.0 mg/kg. The results showed that Napier grass had a good tolerance to Cd, the tolerance index was 0.65~0.79. When the concentrations of Cd were 0, 0.5, 2.0 mg/kg, the bioconcentration factors were more than 1, showing a good ability of enrichment to Cd. Napier grass was not hyper accumulator of Cd because of transfer factors ranged from 0.60 to 0.84, but its restoration efficiency on Cd-contaminated soil was considerable when no exogenous Cd was added resulted from its enormous above ground biomass. And it was the most significant in granitic sandy soil, i.e., 2.48%. In addition, the differences in soil physicochemical properties such as pH, CEC and organic functional groups could also lead to the differences in Cd enrichment in Napier grass. Comprehensive analysis showed that Napier grass was more suitable for the remediation of moderately Cd-contaminated soil, and the remediation efficiency of granitic sandy soil was better than that of purple soil.