Abstract: A plot experiment on the soil derived from oil shale residue in Maoming, Guangdong showed that four herbaceous plants, Vetiveria zizanioides, Pennisetum americarum×P. Purpureum, Paspalum notatum, and Stenotaphrum secundatum, varied in Pb and Cd uptake and distribution. Generally, their concentrations were higher in the ground part than in the aerial. Fertilization reduced the concentrations of the two heavy metals in the plants. On the other hand, increased biomass may raise the uptake rate per unit area. Therefore, when plants are selected for purifying heavy metals in soils, it is advisable to take into account not only their heavy metal uptake ability, but also, or even more, their biomass.

Key words: heavy metal, herbaceous plant, oil shale residue, Pb, Cd, uptake