Figure 2.

Alpha diversity and beta diversity at the species level

A. PCA of all samples at the species level. B. NMDS analysis of all samples at the species level. C. ANOSIM of NMDS results at the species level. D. and E. Shannon index (D) and Pielou index (E) of the alpha diversity at the species level. The two indexes were significantly higher in periodontitis patients than in controls. PCA, principal component analysis; NMDS, non-metric multidimensional scaling; ANOSIM, analysis of similarities.