To study how the incubated sulfate reducing bacteria (SRB) sediment affects U(Ⅵ) bioreduction

the sediment together with ethanol was added into the sediment-groundwater microcosms

which were compared with microcosms amended with both pure SRB and ethanol and with ethanol only. The results indicated that uranium concentrations of the microcosms amended with the incubated SRB sediment together with ethanol

the pure SRB together with ethanol

and ethanol decreased below 0.05 mg·L-1 (GB 23727-2009) at day 19

22 and 28

respectively. The diversity of microbial communities capable of reducing U(Ⅵ) in all the microcosms had no significant difference. The abundances of microbial communities capable of reducing U(Ⅵ) in the microcosms amended with the incubated SRB sediment together with ethanol

and the pure SRB together with ethanol

in which ethanol were 35.3%

32.5% and 13.1%

respectively. The abundance of microbial communities capable of reducing U(Ⅵ) increased when the incubated SRB sediment together with ethanol was added into the sediment-groundwater microcosm. It is indicated that incubated SRB sediment could accelerate the bioreduction of U(Ⅵ) in the microcosm.