Site preparation and fertilization of wet forests alter soil bacterial and fungal abundance, community profiles and CO2 fluxes

•Site preparation and fertilization improves soil conditions for seedling establishment.•Mounding buried the forest-floor, altered the microbial community and reduced respiration.•Drainage increased CO2 fluxes and altered bacterial and fungal community structure.•Fertilization did not alter respiration or microbial abundance, diversity or structure.