Fig. 4: The numbers and relative abundances of P-acquisition AMGs in individual sampling sites.

a The average numbers of all kinds of P-acquisition AMGs detected in the five habitat types. Horizontal lines represent the medians, while the boxes represent the interquartile ranges of the first and third quartiles. The vertical lines indicate the maximal and minimal values. The dots overlaying each bar represent the corresponding data points. Different letters on the top of the bars indicate significant differences between habitat types assessed with the two-sided Wilcoxon test, and the P value indicates the overall difference among all habitat types assessed with the Kruskal–Wallis test. b–f The relative abundances of the four categories of P-acquisition AMGs (illustrated with the bar charts, see scale values on the X-axis of the left-hand side of each panel) and the numbers of all kinds of P-acquisition AMGs (illustrated with white circles, see scale values on the X-axis of the right-hand side of each panel) detected in individual sampling sites. The four categories of P-acquisition AMGs (short for solubilization, mineralization, transporter, and regulator, respectively) are indicated by different colors. Sampling sites are first grouped as per their habitat types [Farmland (b), Forest (c), Grassland (d), Gobi desert (e), and Mine wasteland (f)], and then those within the same habitat type are arranged according to their latitudes (from south to north).