design: Bacterial and archaeal 16S rRNA genes, and fungal ITS genes were PCR-amplified using the barcoded primer pairs 338F (5-ACTCCTACGGGAGGCAGCAG-3) / 806R (5-GGACTACHVGGGTWTCTAAT-3) (Caporaso et al., 2011), 524F-10-ext (5-TGYCAGCCGCCGCGGTAA-3) / Arch958R-mod (5-YCCGGCGTTGAVTCCAATT-3) (Pires et al., 2012) and ITS1F (5-CTTGGTCATTTAGAGGAAGTAA-3) / ITS2R (5-GCTGCGTTCTTCATCGATGC-3) (Li et al., 2020), respectively. Amplicon products were purified using AxyPrep DNA Gel Extraction Kit (Axygen Biosciences, USA) and quantified using QuantiFluorTM-ST (Promega, USA). Adaptor sequences were ligated onto the amplicons for library construction. The libraries were mixed in equimolar amounts, and sequenced using an Illumina MiSeq platform with a paired-end strategy (2250 bp) (Illumina, USA).