Combination　of　taxa　and　function　can　provide　a　more　comprehensive　picture　on　human-induced　microbial　homogenization.　Here,　we　obtained　2.58　billion　high-throughput　sequencing　reads　and　479　high-quality　metagenome-assembled　genomes　(MAGs)　of　planktonic　microbial　communities　in　a　subtropical　river　for　5　years.　We　found　the　microbial　taxa　homogenization　and　functional　homogenization　were　uncoupled.　Although　human　activities　in　downstream　sites　significantly　decreased　the　taxonomic　diversity　of　non-abundant　ASV　communities　(16S　rRNA　gene　amplicon　sequence　variants),　they　did　not　significantly　decrease　the　taxonomic　diversity　of　abundant　ASV　and　total　observed　MAG　communities.　However,　the　total　observed　MAG　communities　in　downstream　sites　tended　to　homogenize　into　some　specific　taxa　which　encode　human-activity-related　functional　genes,　such　as　nutrient　cycles,　greenhouse　gas　emission,　antibiotic　and　arsenic　resistance.　Those　specific　MAGs　with　high　taxonomic　diversity　caused　the　weak　heterogenization　of　total　observed　MAG　communities　in　downstream　sites.　Moreover,　functional　homogenization　promoted　the　synchrony　among　downstream　MAGs,　and　these　MAGs　constructed　some　specific　network　modules　might　to　synergistically　execute　or　resist　the　human-activity-related　functions.　High　synchrony　also　led　to　the　tandem　effects　among　MAGs　and　thus　decreased　community　stability.　Overall,　our　findings　revealed　the　links　of　microbial　taxa,　functions　and　stability　under　human　activity　impacts,　and　provided　a　strong　evidence　to　encourage　us　re-thinking　biotic　homogenization　based　on　microbial　taxa　and　their　functional　attributes.　©　2024　Elsevier　Ltd