Interactions Between Exogenous Rare Earth Elements and Phosphorus Leaching in Packed Soil Columns

Rare earth elements(REEs) increasingly used in agriculture as an amendment for crop growth may help to lessen environmental losses of phosphorus(P) from heavily fertilized soils.The vertical transport characteristics of P and REEs,lanthanum(La),neodymium(Nd),samarium(Sm),and cerium(Ce),were investigated with addition of exogenous REEs at various doses to packed soil columns(20 cm deep).Vertical transfers of REEs and P were relatively small,with transport depths less than 6 cm for most REEs and P.Export of applied REEs in leachate accounted for less that 5% of inputs.The addition of Ce,Nd and Sm to soil columns significantly decreased concentrations of extractable soil P up to a depth of 4 cm,with soil P concentrations unaffected at depths > 4 cm.In general,REEs had little effect on the vertical leaching of P in packed soil columns.

Rare earth elements （REEs） increasingly used in agriculture as an amendment for crop growth may help to lessen environmental losses of phosphorus （P） from heavily fertilized soils. The vertical transport characteristics of P and REEs, lanthanum （La）, neodymium （Nd）, samarium （Sin）, and cerium （Ce）, were investigated with addition of exogenous REEs at various doses to packed soil columns （20 cm deep）. Vertical transfers of REEs and P were relatively small, with transport depths less than 6 cm for most REEs and P. Export of applied REEs in leachate accounted for less that 5% of inputs. The addition of Ce, Nd and Sm to soil columns significantly decreased concentrations of extractable soil P up to a depth of 4 cm, with soil P concentrations unaffected at depths 〉 4 cm. In general, REEs had little effect on the vertical leaching of P in packed soil columns.