Geochemical impact of dissolved organic matter on antimony mobilization in shallow groundwater of the Xikuangshan antimony mine, Hunan Province, China

Contrasting Spectroscopic Characterization and Environmental Behavior of Dissolved Organic Matter in Shallow and Deep Mine Water of Shendong Mining Area, China

“…Notably, 63.16% of the mine water samples had elevated F-concentrations that exceeded China's national standards (1.00 mg/L) for drinking water. These results are similar to those reported by Hao et al [3,32] and Zhang et al [25].…”

“…The significant differences between data (p<0.05) were analysed using the t-test and one-way ANOVA. PARAFAC model analysis and spectral indices, including FI, HIX, BIX, a 254 , S R , and β:α of EEM data were carried out in MATLAB 2012a (Natick, MA, USA) using the DOM Fluor v.1.7 toolbox and EFC v1.2 software, respectively [3,32]. Descriptive data, such as the mean, range, standard deviation, Spearman correlation analysis, and principal component analysis (PCA), were analysed using Origin 2022 (Northampton, MA, USA).…”

“…DOM was measured using a total organic carbon analyser (TOC-5000, Japan) with an analytical precision of ±2%. The fluorescence characteristics of the mine water samples were measured by three-dimensional fluorescence spectrophotometry (F7000, Japan) with excitation and emission slit bandwidths of 5 nm, scanning speed of 500 nm/min, and excitation (Ex) was 250-450 nm with an emission scanning range of 220-520 nm [2,32]. Fluorescence intensities and DOM values were obtained according to the methods described by Malik et al [2], Kulkarni et al [33], and Kulkarni and Mladenov et al [10].…”

“…Component 2 (C2) had excitation peaks at 265 nm and an emission peak at 440 nm, representing higher molecular weight humic acid-like structures [11,16,36]. Finally, Component 3 (C3) displayed Ex/Em maxima at 280/330 nm, corresponding to protein-like components, which are autochthonous DOM in mine water and are associated with microbial activity [32,43]. Compared with C1, C2 comprised compounds that were more hydrophobic and larger in molecular size owing to the longer peak of the excitation and emission wavelengths.…”