highly significantp < 0.05
In the time series of Cr stress, the phylum Actinomycetes ( p < 0.01) and Chloroflexi ( p < 0.05) both displayed highly significant increases followed by decreases, while Firmicutes ( p < 0.05) and Myxococcota ( p < 0.01) displayed significant decreases; the phyla Proteobacteria ( p < 0.01) and Gemmatimonadota ( p < 0.01) both displayed highly significant decreases followed by increases.