赣南富稀土矿区农田土壤中稀土元素的环境化学特征

Environmental chemistry of rare earth elements (REEs) in the cultivated soil of a typical REE mine in the southern Jiangxi

选择江西赣县大田稀土矿区，研究了矿区耕作农田土壤中稀土元素的含量、分布及赋存形态特征。结果表明，该区土壤中稀土元素含量明显高于对照区和全国土壤平均含量，且相对富含重稀土元素。土壤中稀土元素的分布模式受成土母岩及元素性质控制，呈现Eu和Ce负异常。稀土元素主要以可交换态和有机结合态（特别是松结有机态）形式存在，具有较高的活性和生物有效性，可能影响生态环境安全。

Content, distribution and speciation of rare earth elements (REEs) in the cultivated soils from a typical REE mine in the southern Jiangxi, were studied. Results showed that the REE contents of soils in the REE-rich area are obviously higher than that of contrast area and the average value of China soils. The normalized-distribution patterns of soils present the Eu and Ce negative anomalies, which is controlled by the parent rock and the physico-chemical properties of individual REEs. The main forms of REEs in soils are (loosely) bound to organic matters and exchangeable, so REE have higher activity and bioavailability.