Geochemical characteristics of rare earth elements (REEs) in the paddy soil and riceud(Oryza sativa L.) system of Kočani Field, Republic of Macedonia

摘要

In the Republic ofMacedonia, information about rare earth elements (REEs) distribution patterns, transportationudand speciation characteristics (from soil to plants) is very rare. Therefore, the concentrations of REEs in Kočaniudpaddy soils and rice samples from the Republic of Macedonia were measured and evaluated. The elevated concentrationsudof REEs in paddy soils can be explained by contributions fromacidic and intermediate igneous rocks,udwhich are one of the main source materials for Kočani paddy soils. Low percentages of REEs were bound to theudwater-soluble and exchangeable fractions, revealing low mobility of REEs in the investigated paddy soils.udFurthermore, small amounts of REEs were detected in rice (Oryza sativa L.) grain samples. The calculatedudtransfer values (TF) for REEs in rice samples were also very low, confirming a small accumulation of REEsud(La, Ce, Pr, Nd and Sm) by the studied crops and in the Kočani soil–plant system.