Two　mesocosms,　with　and　without　plants,　were　established　in　the　tidal　wetlands　of　the　Minjiang　Estuary,　Southeast　China.　Each　mesocosm　contained　three　elevation　treatments:　control　(CK),　CK-20cm,　and　CK-40cm.　The　CO2　and　CH4　emission　fluxes　under　each　elevation　treatment　in　the　planted　and　unplanted　mesocosms　were　investigated.　Overall,　the　results　showed　that　increased　flooding　did　not　significantly　change　the　total　biomass　or　stem　heights　of　the　plants,　but　it　increased　the　belowground　biomass　and　decreased　the　aboveground　biomass.　In　the　planted　mesocosms,　the　soil　redox　potential　(ORP)　and　dissolved　organic　carbon　(DOC)　concentration　increased　with　increasing　flooding.　In　the　unplanted　mesocosms,　the　DOC　concentration　also　increased　with　increasing　flooding,　but　the　soil　ORP　did　not　change.　In　the　planted　mesocosms,　compared　to　the　CK　treatment,　CO2　emission　flux　increased　by　43%　and　61%,　respectively　and　CH4　emission　flux　increased　by　66%　and　84%,　respectively　for　the　CK-20cm　and　CK-40cm　treatments.　In　the　unplanted　mesocosms,　the　emission　fluxes　of　CO2　and　CH4　did　not　significantly　change　with　increasing　flooding.　Within　50　to　100　years　of　sea　level　rises　in　the　future,　the　sustained-flux　global　warming　potential　of　vegetated　tidal　wetland　will　increase,　while　the　soil　organic　carbon　storage　will　decrease.　Conversely,　in　unvegetated　tidal　wetlands,　the　sustained-flux　global　warming　potential　will　decrease,　while　the　storage　of　soil　organic　carbon　will　not　change.　©　2023　Chinese　Society　for　Environmental　Sciences.　All　rights　reserved.