title: Fractionations of rare earth elements in plants and their conceptive model.
abstract: Fractionations of rare earth elements (REEs) and their mechanisms in soybean were studied through application of exogenous mixed REEs under hydroponic conditions. Significant enrichment of middle REEs (MREEs) and heavy REEs (HREEs) was observed in plant roots and leaves respectively, with slight fractionation between light REEs (LREEs) and HREEs in stems. Moreover, the tetrad effect was observed in these organs. Investigations into REE speciation in roots and in the xylem sap using X-ray absorption spectroscopy (XAS) and nanometer-sized TiO2 adsorption techniques, associated with other controlled experiments, demonstrated that REE fractionations should be dominated by fixation mechanism in roots caused by cell wall absorption and phosphate precipitation, and by the combined effects of fixation mechanism and transport mechanism in aboveground parts caused by solution complexation by intrinsic organic ligands. A conceptive model was established for REE fractionations in plants based on the above studies.
authors: Nanjing Institute of Geography & Limnology, Chinese Academy of Sciences, Nanjing, 210008, China.
authors: ShiMing
authors: S
authors: Ding
authors: Tao
authors: T
authors: Liang
authors: JunCai
authors: J
authors: Yan
authors: ZiLi
authors: Z
authors: Zhang
authors: ZeChun
authors: Z
authors: Huang
authors: YaNing
authors: Y
authors: Xie
mesh_terms: D005591:Chemical Fractionation; D008674:Metals, Rare Earth / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D008954:Models, Biological; D018515:Plant Leaves / Q000737:chemistry / Q000166:cytology / Q000378:metabolism; D018517:Plant Roots / Q000737:chemistry / Q000166:cytology / Q000378:metabolism; D013025:Glycine max / Q000737:chemistry* / Q000166:cytology / Q000378:metabolism*
chemical_list: D008674:Metals, Rare Earth