FIGURE 4.

Relative abundance on 0 day and decomposition of 16S rRNA gene at operational taxonomic unit (OTU) level in H₂¹⁸O light fraction (dead bacteria and archaea) at different times. This was assessed by calculating percentage of absolute abundance loss of 16S rRNA gene after 15 and 30 days. G+ in parentheses represents gram-positive bacteria, and G− in parentheses represents gram-negative bacteria. Points are average of four replicates, and bars show standard errors of means with four replicates.