[Species dynamic change of added Rare Earth element in soil]

After Rare Earth elements (REEs) was applied into soil, content of exchangeable species decreased obviously with time lapsing. The fastest decrease of content of exchangeable species occurred at wheat tillering stage. A part of the lost content of exchangeable species was absorbed by wheat, and the other part of that was absorbed by soil. The surface activity of iron/manganese oxide was influenced obviously by the secretion function of root, content of iron/manganese oxide binding species rapidly increased before wheat jointing stage, but it decreased quickly after wheat jointing stage. At all time, content of carbonate binding species decreased with time lapsing, and content of residual species and content of organic binding species didn't change.