Fig. 4
Water column microbial communities shifted under elevated pCO2. a Relative abundance of the 15 most abundant bacteria classes in seawater metagenomes. b MDS plot for the relative abundance of the seawater holding tanks taxonomic similarities by class contribution (Bray-Curtis similarity). Seawater metagenomes were represented by pCO2 treatment, green triangle for live rhodolith in ambient air (T1 – tank 1), blue triangle for high pCO2 treatments - both calcareous skeleton (T2 – tank 2) and live rhodolith (T3 – tank 3), light blue square for dead rhodolith (calcareous skeleton in ambient air (T4 – tank 4). The respective color dashed lines connect the temporal sequence of each specific pCO2 treatment in the plot. Water metagenomes from each one of the four tanks were sequenced from days 0, 1, 7, 40 (0d, 1d, 7d, 40d, respectively)