Figure 1
nMDS analysis of the microbial community compositions estimated by T-RFLP (a, b) and 454 pyrosequencing (c, d), calculated from the presence/absence-based Sørensen index (a, c) and the abundance-based Horn index (b, d). Kruskal's standardized stress values (S) below 0.2 indicated acceptable representation of the calculated similarities. Circles represent the bulk (16S rRNA gene based), crosses the active (16S rRNA-based) community compositions, brown the biofilm community humic stream, orange the biofilm community outflow stream, red the biofilm community confluence stream, green the suspended community humic stream, blue the suspended community outflow stream and turquoise the suspended community confluence stream.
