g1CYF-2_formate amended
The archaeal 16S rRNA genes were amplified using primers of 519F/915R. The amplicon product was then sequenced by a NovaSeq6000 sequencer (Illumina) with paired-end 250 bp mode. All the sequence data were first filtered to remove the low-quality reads. The filtered reads were further analyzed according to the Qiiime2 pipeline.