Heavy metals or heavy muscles-the effect of natural organic amendments on Zn and Ni hyperaccumulators Thlas pi caerulescens and Alyssum murale

摘要

Amendment-enhanced phytoremediation experiments were conducted on heavy metal-containing Australian soils, in order to determine if local, naturally-occurring organic amendments increased phytoextraction potential and biomass production. The experimental soils included a loamy sand from beneath electrical transmission towers in suburban Melbourne (2,100 to 4,200ppm Zn) and a loamy clay serpentinite from the Greenvale Mine Site, Queensland (2,600 to 4,500ppm Ni). Glasshouse phytoremediarion experiments were conducted using the hyperaccumulators Thlaspi caerulescens and Alyssum murale. The amendments, peat and brown coal-derived organic humate, both occur naturally within Victoria. Zn and Ni were shown to be extracted from the amended soils and accumulated into the aboveground parts of the hyperaccumutators in concentrations less than that of unamended soils. A plot of dry weight versus leaf metal concentration showed the uptake of both metals to be lowest after the addition of peat, though both amendments decreased metal uptake.