Screening the phytoextractability of trace metals by Aloe cryptopoda Baker and Aloe vera (L.) Burm.f. cultivated on mine tailings

Considering the impact that mining has on the environment, especially by metal-contaminated tailings, and the legal South African requirements for post mine rehabilitation, the study aimed to investigate whether plant species of the Aloe genus could act as phytoextractors of heavy metals. By means of controlled experi-ments, plant biomass and trace metal contents of leaves of Aloe cryptopoda and A. vera grown in gold and platinum mine tailings were evaluated to assess their performance in heavy metal polluted soil and their potential as phytoextractors. A. vera had the higher productivity levels in general, although both species showed decreased biomass production in the contaminated soil over time. A. cryptopoda had the higher trace metal concentrations, similar to those of phytoremediators recommended in other studies and can, therefore, be used as a viable phytoextractor of especially chromium and copper. (c) 2021 SAAB. Published by Elsevier B.V. All rights reserved.