Effect of Amendments on Growth and Element Uptake of Pakchoi in a Cadmium, Zinc and Lead Contaminated Soil

A pot experiment was carried out to study the effects of two amendments, lime and calcium magnesium phosphate, on the growth and Cd, Pb, Zn, Cu, Mn, Fe, N, P and K uptake of pakchoi (Brassica chinensis) in a Cd, Pb and Zn polluted acid soil in the southern part of China. The growth of pakchoi was apparently improved by lime and calcium magnesium phosphate application, the uptake of Cd, Pb, Cu and Zn by pakchoi was significantly depressed and the symptom caused by heavy metals pollution was eliminated. Meanwhile, the absorption of N, K and Mn was also inhibited by these amendments. Soil pH was the main factor controlling the uptake of the heavy metals by pakchoi. This suggests that lime and calcium magnesium phosphate could be used as effective amendments for eliminating the toxicity of heavy metals to the vegetable and inhibiting their absorption by the crop.