Relationship between percentages of fungal (18S/16S) and PAH-degrading bacterial communities (PAH-RHD_α GN and GP/16S), sum of 16 PAH concentrations, weight of rhizosphere soil, root biomass, and rhizotron depth for alfalfa (orange) and ryegrass (green).

<p>Correlation clouds show the data from the 56 soil samples (diamonds). Mean values (n = 7) per class (squares and full line) and class standard deviations (triangles and dotted lines) are represented. For each relationship, the Spearman’s correlation coefficient (r) and the non-linear correlation coefficient (η²) were calculated.