design: Primers for the full-length bacterial 16S rRNA gene (27F: 5'-AGRGTTYGATYMTGGCTCAG-3' and 1492R: 5'-RGYTACCTTGTTACGACTT-3') were employed to amplify the target fragment from the successfully extracted DNA. The procedures for PCR amplification, product purification and amplicon library construction were conducted in accordance with the methodology outlined by Gao et al. (2022). Amplicon sequencing was conducted using a PacBio Sequel platform at Shanghai Biozeron Biotechnology Co., Ltd. (Shanghai, China).