Effect of lime with peat addition on heavy metal uptake by pakchoi

Effect of lime and peat application on the uptake of Cd, Pb, Zn, Cu, Mn and Fe of pakchoi ( Brassica chinensis ) was studied by pot experiment in cadmium, lead and zinc contaminated soil. Lime, lime with low peat addition, lime with high peat addition all significantly inhibited the uptake of heavy metals by pakchoi. The available heavy metals of Cd, Zn and Pb in soil significantly negatively correlated with soil pH ( R 2: 0.78 *** -0.84 *** ). The contents of Cd, Pb and Zn in pakchoi positively correlated with their available contents in soil ( R 2: 0.45 ** -0.86 *** ). Significant binomial correlation existed between the contents of Cd, Pb and Zn in pakchoi and soil pH ( R 2: 0.87 *** -0.95 *** ). Zn, Cd and Pb concentrations in pakchoi decreased as soil pH increased, while soil pH higher than 6.70, Zn, Cd and Pb concentrations increased slightly.