Evaluation the remediation effects of amendments in heavy metal polluted red soil

A pot experiment was carried out in greenhouse to observe the yield, the absorption amount of cadmium and zinc of rape（Brassia campestris L.）, and soil pH responses to different amendments (lime, manure and sepiolite) applied in red soil, a typical soil of China. The results indicated that the biomass yield of rape increased after amendments application. The treatment of lime，manure and sepiolite co-application showed the highest yield, which increased 15 times comparing with no amendments application. The soil pH was increased in various degrees with different amendments or their co-application. Application lime could increase soil pH around 2 units. This made the absorption amount of cadmium and zinc was very low. The uptake coefficient of Cd was bigger than that of Zn, which implied that Cd was easy move from soil to plant. The uptake coefficient was decreased with application lime especially. The content of Zn in rape decreased lower than the food standard after application of lime to red soil. The aftereffect of amendments on soil pH was worn off with time. The aftereffect of amendments to Cd was better than that of Zn.