The effect of EDTA on rare earth elements bioavailability in soil ecosystem

In this paper, the effects of the organic ligand EDTA on the bioaccumulation of rare earth elements (REEs) by wheat seedlings growing in two types of soils were investigated. The results indicate that the bioaccumulation values of REEs in wheat roots were much higher than those in the tops (stems and leaves) for both types of soils. Adding the organic ligand (EDTA) promoted the REEs bioavailability of wheat by increasing the REEs desorption from soils. Not only bioaccumulation of REEs in roots and tops of wheat but also the REEs desorption amount from soil had good correlation with the concentration of EDTA in the soils. Also, a good correlation existed between the REEs desorption amount and their contents in wheat seedlings for the same EDTA concentration, The REEs bioaccumulation values of wheat seedlings in Yellow-brown soil were a little higher than that in Black soil. (C) 1999 Elsevier Science Ltd. All rights reserved.