16S-seq of sediment
The V4-5 regions of 16S rRNA genes were amplified with primers 515F/926R. PCR was carried out with denaturation at 94  for 5 min, 31 annealing cycles at 94  for 30 s, 53  for 30 s and 72  for 30 s, followed by elongation at 72  for 8 min.