Fig. 2.

NMDS ordination (Bray–Curtis distance) of ARISA-derived bacterial community profiles, with at least three sediment replicates per sample. A posteriori groupings are specified according to (A) sand type, (B) season and (C) sediment depth, all including in/out-reef location. Samples chosen for 16S-ITS rRNA clone libraries are encircled. Objects plotting closer to each other share a more similar community structure relative to other, more distant objects. The low stress value of 0.18 indicates the goodness-of-fit of the two-dimensional representation compared with the original matrix.