FIG 4.

2D-NMDS plots comparing similarities of microbial communities in tailings (based on Bray-Curtis matrices) in dependence on pH (A), concentrations of Fe (g liter⁻¹) (B), SO₄²⁻ (g liter⁻¹) (C), total C (wt%) (D), and total S (wt%) (E), determined by high-throughput amplicon sequencing. Total C and S were determined in solid phases, other parameters in pore water samples. For used metadata, see Table 1. For better visualization, this value (1.764 g liter⁻¹) (■) was not included in the color range.