Quantification of 16S rRNA gene and ITS fragment copy numbers in the two compartments of the split-root boxes for the four treatments -ARD/-ARD; +ARD/+ARD; -ARD/+ARD; Control/+ARD based on soil dry weight (bulk and rhizosphere soil) or centrifuged soil sample (rhizoplane), respectively.

Data are provided separately for three microhabitats (rhizoplane, rhizosphere and bulk soil) at the end of the 34-day growth period. +ARD soil (black), -ARD soil (white), Control soil (cross-hatched). Different letters indicate significant differences at p<0.05 (only shown for bulk soil). Means of four replicates. Error bars show SE.