Fig. 5

Effects of different Pb and Cd concentration treatments on root enrichment factors and plant transport coefficients of Sedum alfredii Hance. The Pb and Cd enrichment factor is determined by the ratio of Pb and Cd content in the root system to Pb and Cd content in the rhizosphere soil. Pb and Cd transport coefficient is obtained from the ratio of Pb and Cd concentration aboveground and Pb and Cd content in the root system. EF: enrichment factor; TC: transport coefficient. A shows the Pb enrichment of plants under different treatment conditions, and B shows the enrichment of Cd; C shows the transport of Pb to plants under different treatment conditions, and D shows the transport of Cd. Different letters indicate a significant difference at P < 0.05