Transfer kinetics of cadmium from naturally enriched rocks to Lupinus albus

摘要

A laboratory experiment was used to study Cd transfer from rock to soil and then to plants. Microcosms were filled with a Cddepleted soil containing small pieces of Cd-enriched carbonate rocks. Then, seeds of Lupinus albus were sown and the experiment was set up over 1 year and 3 year periods. The first results after one year revealed Cd accumulation in the cluster roots. Cadmium availability would be favoured by its complexation with the excreted organic acids. The aerial biomass of lupine did not show a significant Cd accumulation. Surface weathering was observed on carbonate slices from root activity. Improved conclusions are expected from the results of the 3 year study period. However, it is assumed that lupine will mobilize Cd by increasing the rhizosphere soil acidity and could incorporate this trace element directly.