The potential of some indigenous microorganisms and plants for the removal of heavy metals from soil

Abstract

Heavy metals found in soils from different industrial sources or mining activities are persistent inorganic pollutants able to bioaccumulate along the food chain and cause negative effects in theenvironment and for human health. Differentphysical, chemical and biological processes are applied for their removal from soil environments. Biological processes become more and more preferred, since bioremediation strategies have often proved to be more advantageous than the conventional remediation tools, mainly because these processes can be implemented directly onto the contaminated sites (in situ). In this context, the present paper examines the abilityof microorganisms and plants to remove heavy metals from soil, in terms of tolerance and bioaccumulation. A particular interest is given to the bioaccumulation processes of metals by proteobacteria, bacilli and actinobacteria, alone or in synergismwith indigenous plants. Also, some advances in the biosorption of highly toxic heavy metal ions as Cr(VI) and Cd(II) are just discussed,together with various strategies and practices to explore the synergism between microorganisms and plants as valuable biological resource for increasing tolerance against heavy metals and strengthening the bioremediation processes.