Figure 2.

Heterogeneity between the different seafloor types. The color legend as given in B is true for the whole figure. Samples from the Saganaki dataset have a red border, while the ones from the CarDHynAl dataset have a black border. (A) Form CoDa-biplot, representing 44% of the variance. It approximately reflects the Aitchison distances between the 16S rRNA composition of the sample at the family taxonomic level. Each linked samples represent a core, with the width of the link being proportional to depth of the sample. (B) Covariance CoDa-biplot where the center of each seafloor type is shown, as well as the taxa involved in the balances described in the text. (C) Shannon diversity index of each sample grouped per seafloor type. (D) Absolute prokaryotic abundance as copies of 16S rRNA per gram of sediment quantified by qPCR. For (C,D), the seafloor types are ordered by increasing temperature/hydrothermal influence, and the bars represent the median.