Fig 1.
A) Experimental setup and timeline. Each circle represents one microcosm. Microcosm bottles are destroyed during simulated leachate chemistry analyses. T1, T2, T3, T4, T5, and T6 correspond to time points when DNA was sampled during the experiment. B) Depiction of assembled microcosm in 100 mL bottle. C) Centrifuge tube with glass beads, which are inserted into the microcosm during assembly. Arrows point to perforations in the tubes through which microcosm liquid can flow to the beads.
Table 1.
Average concentrations of total iron, ferrous iron, sulfide, sulfate, and pH in triplicate live microcosms.
Data are reported in mg/L for all chemical species. N.d. = not detected.
Fig 2.
A) PCoA of Euclidean distances. B) NMDS of Bray-Curtis distances.
Table 2.
Results of pairwise PERMANOVA tests for Euclidean distances between groups.
P values were adjusted for multiple testing using the Bonferroni method. Pairwise comparisons between sample times (i.e. T1-T6) include only untreated microcosms. Post-treatment groups include both T5 and T6.
Fig 3.
A) Chao1 B) Shannon-Weaver alpha diversity metrics. Wilcoxon-rank sum testing was conducted to test for significant differences in diversity between the untreated control and each treatment. P <0.01 is indicated by "**", not significant is indicated "ns".
Table 3.
Results of pairwise PERMANOVA results for Bray-Curtis distances between groups after treatment addition.
Results include both T5 and T6. P values were adjusted for multiple testing using the Bonferroni method.
Fig 4.
Average relative abundance of taxa.
A) shows Phylum level classification and B) shows Genus level classification. Each stacked bar represents the average relative abundance for microcosms replicates at each sampling time. Treatments were added at after T4.
Fig 5.
Differentially abundant taxa as determined by ANCOM-BC testing for a) antibiotic treatment and B) Fe(OH)3 treatment compared to untreated control microcosm. Natural log fold change reported on the Y axes. P = Phylum, G = Genus.