Fig. 7: Relationships between the relative abundance of oligotrophic bacteria and soil pH and C/P, and relationship between bacterial O/C and the Chao1 index under wetland degradation.

The relative abundance of oligotrophic bacteria is plotted against soil pH (a) and soil C/P (b), and the bacterial O/C is plotted against the Chao1 index (c). The desirable regression curve was selected based on a smaller Akaike’s information criterion (AIC) and a relatively larger R² simultaneously. The lower the AIC and the higher the R², the better the model. The analysis results and the equations of the fitted curves are shown in Supplementary Table 1 and Supplementary Table 2, respectively.