Xue Shengguo, Zhu Feng, Kong Xiangfeng, Wu Chuan, Huang Ling, Huang Nan, Hartley William
School of Metallurgy and Environment, Central South University, Changsha, 410083, People's Republic of China.
Crop and Environment Sciences Department, Harper Adams University, Newport, Shropshire, TF10 8NB, UK.
Environ Sci Pollut Res Int. 2016 Jan;23(2):1120-32. doi: 10.1007/s11356-015-4558-8. Epub 2015 Apr 26.
Bauxite residue (Red mud) is produced in alumina plants by the Bayer process in which Al-containing minerals are dissolved in hot NaOH. The global residue inventory reached an estimated 3.5 billion tons in 2014, increasing by approximately 120 million tons per annum. The appropriate management of bauxite residue is becoming a global environmental concern following increased awareness of the need for environmental protection. Establishment of a vegetation cover is the most promising way forward for the management of bauxite residue, although its physical and chemical properties can limit plant growth due to high alkalinity and salinity, low hydraulic conductivity, trace element toxicity (Al and Fe), and deficiencies in organic matter and nutrition concentrations. This paper discusses the various revegetation and rehabilitation strategies. Studies of the rehabilitation of bauxite residues have mainly focused on two approaches, amelioration of the surface layer and screening of tolerant plants and soil microorganisms. Amendment with gypsum can reduce the high alkalinity and salinity, promote soil aggregation, and increase the hydraulic conductivity of bauxite residues. Organic matter can provide a source of plant nutrients, form stable complexes with metal cations, promote hydraulic conductivity, stabilize soil structure, and provide an energy source for soil organisms. Tolerant plants and microorganisms such as halophytes and alkaliphilic microbes show the greatest potential to ameliorate bauxite residues. However, during restoration or as a result of natural vegetation establishment, soil formation becomes a critical issue and an improved understanding of the various pedogenic processes are required, and future direction should focus on this area.
铝土矿残渣（赤泥）是氧化铝厂采用拜耳法生产氧化铝时产生的，在该过程中，含铝矿物溶解于热的氢氧化钠溶液中。2014年，全球铝土矿残渣存量估计达到35亿吨，且以每年约1.2亿吨的速度增长。随着人们对环境保护需求的认识不断提高，铝土矿残渣的妥善管理正成为一个全球环境问题。虽然铝土矿残渣的物理和化学性质因高碱度、高盐度、低水力传导率、微量元素毒性（铝和铁）以及有机质和养分浓度不足而可能限制植物生长，但建立植被覆盖是铝土矿残渣管理最有前景的方法。本文讨论了各种植被恢复和复垦策略。对铝土矿残渣复垦的研究主要集中在两种方法上，即表层改良以及耐受力强的植物和土壤微生物的筛选。添加石膏可以降低高碱度和高盐度，促进土壤团聚，并提高铝土矿残渣的水力传导率。有机质可以提供植物养分来源，与金属阳离子形成稳定的络合物，促进水力传导率，稳定土壤结构，并为土壤生物提供能量来源。耐受力强的植物和微生物，如盐生植物和嗜碱微生物，在改良铝土矿残渣方面显示出最大潜力。然而，在恢复过程中或由于自然植被的建立，土壤形成成为一个关键问题，需要更好地理解各种成土过程，未来的方向应聚焦于这一领域。
