Phytoremediation of Rare Tailings-Contaminated Soil

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 che-mical remediation methods of contaminated soil,phytoremediation is regarded as the most promising green in-situ restoration technology.The purpose of this review is to efctive 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 applcation strategies of phytoremediation were elaborated.In additon,the cases of spedies with tolerance to uranium thorium,tantalum niobium as well as REEs and their remediation mechanisms were summarized,respectively.Particularly,the typical plants represented by Bras-sica juncea,Sunflower,Phytolacca americana,Dicramopteris dichotoma,Salix SPP,etc,were very efctive in the reme-diation of rare tailings.The infuence factors of phytoremediation eficiency of tailings contaminated soil were discused.Two main factors were the mobility of heavy metals in soil(external cause)and the ennichment ability of species(inter-nal cause).Since the traditional phytoremediation also had some limitations in view of this,the work discussed some auxiliary methods(such as chelaing agents or microbial assisted restoration)to improve the effiency of phytoreme-diation.Finally,the future development of phytoremediation and potential applcation directions were explored.