For all subsequent β-diversity analyses, an OTU table without singletons was used to account for noise in the data (e.g., Reeder and Knight 2009). Differences among habitats within the fungal sub-community were examined with a non-metric multidimensional scaling (NMDS) ordination plot based on the Cao distance (Cao et al. 1997), which accounts for variable sampling intensity. Ellipses correspond to the standard deviation around the habitat group centroids. Stress values below 0.1 can be considered as a very good fit. We additionally tested for significance when separating habitats (excluding Reed) and POM type and using a PERMANOVA (1000 permutations) on the distance matrices. The robustness of the results were evaluated by comparing them with a presence/absence transformed OTU matrix using Jaccard distances, as well as with a classified taxonomy abundance table generated with SILVA NGS (see below) using Cao distance. Both additional analyses resulted in similar outcomes (Suppl. material 6).