中文摘要：

有关对稀土农用的理论和实践、天然和农业生态系统中稀土的地球化学行为及稀土的增产生理过程与毒理等方面已开展了大量研究，而对稀土进入植物体内的迁移过程、分布分异现象和机制缺乏必要的了解。稀土元素在植物中的分异研究有助于“示踪”稀土元素在土壤（溶液）．植物系统中的迁移路径，进而查明控制稀土元素迁移和积累的体外和体内敏感因素。本文结合近5年的研究工作，就近年来国内外有关稀土元素在植物中的分异现象、机制及其研究意义进行了综述，并展望了此方面的研究趋势，期望能为稀土以及重金属的生物有效性研究开辟一条新思路。

英文摘要：

Lots of studies on rare earth elements （REEs） have been carried out in many aspects, such as theory and practice of REEs application in agricul- ture, geochemical behaviors of REEs in natural and agricultural ecosystem, mechanisms of production en- hancement with REEs fertilizer and toxicology of REEs. However, process of REEs transferring into plant body, features and mechanisms of distribution and fractionation of REEs in plants are not clear so far. Characteristics of REE fractionations in plants can be used to ＂trace＂ the pathway of REE transportation from soil （solution） to plant. Study of mechanisms on REE fractionations is good to investigate the control- ling factors, including both inside factors and outside factors. This paper detailedly reviewed the characteris- tics and mechanisms of REE fractionations in plants and their significance for research. Furthermore, the future directions in these fields were proposed. We hope all related research can be used for reference on bioavailability of REEs and heavy metals.