Figure 2.

Difference in microbial richness between the spring water and the biofilm: presence and absence of subfamilies in spring water (SW) and biofilm samples (BF). Color intensities (red) of the biofilm samples reflect the number of times the subfamily was called present in one of the three replicates. As the SW sample was not replicated, heatmap reflects presence (blue label) or absence only. The Neighbor Joining tree was constructed with one representative OTU per subfamily (branch length is ignored). Leaf IDs give the classification on family level and the accession number of the representative OTU. Only those subfamilies that occurred in the water sample or in at least 2/3 of the biofilm replicates are shown.