Figure
2: Log2 fold change in relative abundance of ASVs in the DEP treatment
in comparison to the control. Cutoff for inclusion of ASVs in this plot
was FDR (=Padj) < 0.01. Colors represent most
specific taxonomic label.
𝛼-diversity of the gut microbiome
The number of observed ASVs did not differ between treatments (GLM with
gamma distribution: F3,69 = 0.3008, P = 0.825;Figure 3A ). Pielou’s evenness differed between treatments
(Kruskal-Wallis rank sum test: X 2 = 23.296, df
= 3, P < 0.001; Figure 3B ). The DEP treatment had a
significantly lower evenness than the other treatments (Dunn’s
comparisons with Benjamini-Hochberg (BH) adjusted p-values: DEP vs.
control P < 0.001, DEP vs. solvent control P< 0.001, DEP vs. brake dust P < 0.001; Figure3B ). Shannon diversity differed between treatments
(Kruskal-Wallis rank sum test: X 2 = 14.642, df
= 3, P = 0.002; Figure 3C ). The DEP treatment had a
significantly lower diversity than the other treatments (Dunn’s
comparisons with BH adjusted p-values: DEP vs. control P = 0.003,
DEP vs. solvent control P = 0.001, DEP vs. brake dust P =
0.010; Figure 3C ). Faith’s PD differed between treatments
(Kruskal-Wallis rank sum test: X 2 = 10.777, df
= 3, P = 0.013; Figure 3D ). Faith’s PD in the DEP treatment was
significantly higher than in the other treatments (Dunn’s comparisons
with BH adjusted p-values: DEP vs. control P = 0.009, DEP vs.
solvent control P = 0.009, DEP vs. brake dust P = 0.007;Figure 3D ).