Bauxite residue is often physically degraded, which limits vegetation establishment on the disposal areas. Microaggregate stability is an important physical property due to its significant effect on erosion and surface runoff; however, this is rarely reported for bauxite residue. Native plant encroachment on a bauxite residue disposal area in Central China has revealed that natural regeneration may ameliorate the residue and help to support plant growth. Residue samples from 5 different disposal ages were collected to determine microaggregate stability and to identify their fractal features. Following natural regeneration, the aggregate fraction 250-50 μm increased significantly from 27.4% to 40.3%, whilst the silt + clay size aggregate fraction decreased from 58.4% to 30.7%. With increasing disposal age, the residue clay dispersion ratio (CDR) ranged from 7.7% to 22.5%, whilst aggregated silt and clay ranged from 15.3% to 19.0%, Residues from mineral ore processing are disposed on land in large residue disposal areas, which may eventually create a series of ecological and environmental issues (Smart, Callery, & Courtney, 2016;Wu et al., 2016;Xue et al., 2017). In the aluminium industry, bauxite residue is an alkaline solid by-product generated when alumina is extracted from bauxite ore by the Bayer process (Goloran, Phillips, & Chen, 2016;Kong, Guo et al., 2017). The global inventory has reached 3.4 billion tons, with an annual increase of 120 million tons (Kong, Li et al., 2017;Xue, Kong, et al., 2016a). Large volumes of bauxite residue are deposited in bauxite residue disposal areas, which cause potential environmental risks, as these bare areas are sensitive to erosion by wind and water, and can be regarded as a potential source of contamination due to their high alkalinity and salinity (Gelencsér et al., 2011;Ruyters et al., 2011). In situ rehabilitation and revegetation may, however, stabilize the residue surface and minimize wind erosion (Courtney, Jordan, & Harrington, 2009;Kaur, Phillips, & Fey, 2016;Schmalenberger, O Sullivan, Gahan, Cotter, & Courtney, 2013). Its poor physical structure is nevertheless a major limitation to support plant growth (Liu, Naidu, & Ming, 2013;Zhu, Huang, Xue, William, Li, Zou, 2016a With the development of soil fractal theory, the limitation of single-fractal dimension has been stressed to describe soil particle size distribution. In order to obtain more detailed information of soil structure, multifractal theory was introduced to soil science (Li, Liu, & Jiang, 2016). Rodríguez-Lado and Lado (2016) found that particle size distribution behaved as multifractals, with scaling properties varying in different soil samples, whilst values of fractal dimension may be related to the degree of evolution of the soils. Peng et al. (2014) found that the single-fractal and multifractal parameters could describe soil particle size distribution and the influences of soil structure effectively. inductively coupled plasma atomic emission spectroscopy (Jones et al., 2011). Exchan...