Figure 3

Relative abundance of bacterial 16S rRNA genes in the gradient fractions. (a) PL sludge (0.05 d⁻¹), propionate treatments, 7 d-incubation; (b) PL sludge, acetate treatments, 7 d-incubation; (c) PL sludge, propionate treatments, 14 d-incubation; (d) PL sludge, acetate treatments, 14 d-incubation; (e) PH sludge (0.15 d⁻¹), propionate treatments, 5 d-incubation; (f) PH sludge, acetate treatments, 5 d-incubation; (g) PH sludge, propionate treatments, 10 d-incubation; (h) PH sludge, acetate treatments, 10 d-incubation. (1), (2) and (3) in each figure means three replicates. The fractions labeled with filled dot were used for 16S rRNA gene sequencing. The filled dot in (a) named LL, L, M and H from buoyant density 1.68–1.73 g mL⁻¹; the filled dot in (b,d,e, f,h) named L, M and H from buoyant density 1.69–1.73 g mL⁻¹; the filled dot in (c,g) named L, M, H and HH from buoyant density 1.69–1.74 g mL⁻¹.