| Abstract |
In order to achieve the goal of circular economy and sustainable development of ecological environment, it is important to separate and recover associated elements from rare mineral resources. Compared with traditional physical and chemical remediation methods of contaminated soil, phytoremediation is regarded as the most promising green in-situ restoration technology. The purpose of this review is to effectively alleviate the environmental problems caused by rare tailings contaminated soil through phytoremediation and realize the recovery of uranium-thorium, rare earth elements (REEs) and tantalum-niobium. This review took rare tailings with uranium-thorium, REEs, tantalum-niobium in China as the research object, then the background, significance, mechanisms and application strategies of phytoremediation were elaborated. In addition, the cases of species with tolerance to uranium-thorium, tantalum-niobium as well as REEs and their remediation mechanisms were summarized, respectively. Particularly, the typical plants represented by Brassica juncea, Sunflower, Phytolacca americana, Dicranopteris dichotoma, Salix spp., etc., were very effective in the remediation of rare tailings. The influence factors of phytoremediation efficiency of tailings contaminated soil were discussed. Two main factors were the mobility of heavy metals in soil (external cause) and the enrichment ability of species (internal cause). Since the traditional phytoremediation also had some limitations, in view of this, the work discussed some auxiliary methods (such as chelating agents or microbial assisted restoration) to improve the efficiency of phytoremediation. Finally, the future development of phytoremediation and potential application directions were explored. |
