Preliminary assessment of revegetation potential through ryegrass growing on bauxite residue

Bauxite residue (BR), a by-product of the industrial production of alumina, has raised environmental concerns in the last decades, due to the presence of high amounts of alkali and various heavy metal ions. Limited studies on the application of abandoned BR with massive consumption have been reported. In this study, the possibility of the revegetation using ryegrass growing on BR was discussed mainly through the growth indications and transfer of heavy metal ions in BR and plants. In the pot trails, ryegrass was seeded on BR, de-alkali BR, with (DBRO) or without (DBR) organic fertilizer, respectively. The results indicated that the remediation of bauxite residue can be achieved through de-alkali with acid neutralization. Elemental analysis indicated that the elements, except for Fe, Mn and Pb, were stable in plant roots, and ryegrass could hardly absorb Cd. But, some heavy metals such as Cu enriched in plants, which should be noted in revegetation on bauxite residue.