Submitted to: Pedosphere
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/30/2011
Publication Date: 9/30/2011
Citation: Liang, T., Song, W., Wang, L., Kleinman, P.J., Cao, H. 2011. Interactions between exogenous rare earth elements and phosphorus leaching in packed soil columns. Pedosphere. 20(5):616-622. Interpretive Summary: Eutrophication is a major concern in China, highlighted by widely reported algal blooms in China’s lakes, rivers and coastal estuaries. As a result, there is new focus on the management of nutrients in Chinese agriculture, particularly phosphorus. We investigated the effect of rare earth elements, which are increasingly used in China as soil fertility amendments, on leaching losses of phosphorus. Although the application of rare earth elements significantly lowered phosphorus solubility in surface soils, they had little effect on losses of phosphorus to leaching water, which were generally quite low. Results suggest that rare earth elements may play a more important role in controlling phosphorus losses in surface runoff, or in leachate from soils with higher phosphorus leaching potential.
Technical Abstract: 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 greater than 4 cm. However, REEs had little effect on the vertical leaching of P in packed soil columns.