Phytoremediation - A sustainable approach for contaminant remediation in arid and semi-arid regions - a review

Existing information relating to the application of phytoremediation in arid regions, for mitigating the toxicity of organic and inorganic contaminants is summarized, emphasizing the comparative merits of different phyto-strategies. Adverse climatic conditions in arid and semi-arid environments along with the intrinsic abiotic stresses need specific considerations, which are discussed here. The current "state of art" for petrochemical and metal phytoremediation, as well as phytodesalination is presented, making it possible to choose the very best decision, when the technology is applied for various contaminant scenarios. Information is also provided on contaminants in arid regions, remediation approaches and different phytoremediation strategies to be adopted, depending on the nature of contaminants and the site situations. Furthermore, phytodesalination may well occur in parallel with phytoremediation of heavy metal polluted soils in arid regions, enhancing the potential of this process. This has drawn a great deal of interest during recent years and is reviewed here. Finally, the lacunae in the current knowledge are identified, which has to be addressed to improve the effectiveness of phytoremediation under arid conditions.