Fig. 2.

Multivariate ordination showing the effects of microbe history, plant history, and contemporary soil moisture on microbial community composition. Microbe history affected the composition of soil fungi (Upper) and bacteria (Lower), as indicated by the strong separation of samples along PCoA axis 1. Dashed ellipses contain dry-adapted microbial assemblages, and solid ellipses include wet-adapted microbial assemblages. PERMANOVA confirmed the effect of the microbe-history treatment on both fungal and bacterial composition (P = 0.001). Although not as strong as microbe history, contemporary soil moisture (white symbols, dry; gray symbols, wet) significantly affected the composition of bacteria (P = 0.039) and marginally affected the composition of fungi (P = 0.096). In contrast, plant history (dry plants, circles; wet plants, squares) had no effect on fungal or bacterial composition (P = 0.55 and P = 0.22, respectively). Ordinations were created with the output of PCoA, and the percent variation explained by each PCoA axis is presented in parentheses in each axis label.