Preliminary assessment of revegetation potential through ryegrass growing on bauxite residue

Abstract

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.摘要赤泥是氧化铝工业生产的副产品,由于存在大量的碱和各种重金属离子,在过去几十年中逐渐 引起了人们对环境的关注。目前,有关赤泥大宗消纳利用的研究还比较少。本文主要从生长指标和重 金属离子在黑麦草和植物体内的转移来探讨利用黑麦草在赤泥堆场上进行复垦的可能性。盆栽试验表 明,通过酸中和脱碱,可以实现赤泥的修复。元素分析表明,除铁、锰、铅外,大部分元素在植物根 系中是稳定的,而黑麦草几乎不能吸收镉。但是,一些重金属如铜在植物体内富集,这在赤泥的植物 修复中应引起重视。