Electricity production and evolution of microbial community in the constructed wetland-microbial fuel cell

Constructed wetlands combined with microbial fuel cell (CW-MFC) could purify the wastewater while using microorganisms to generate electricity. Our study investigated pollutant removal and microorganism evolution in CW and CW-MFC. The average removal rate of total nitrogen (82.46 +/- 4.74%) in the CW-MFC was highly significant (p < 0.01) higher than that in the CW. The average removal rate of chemical oxygen demand (82.32 +/- 12.85%) and total phosphorus (95.06 +/- 5.45%) in the CW-MFC were higher than those in the CW. In the CW-MFC, the average voltage was 265.77 +/- 12.66 mV and the highest power density was 3714.08 mW center dot m(-2). The microbial community diversity and richness of the CW-MFC system were higher than those of the CW system. The read number of ammonia oxidizing (149 +/- 7), nitrite-oxidizing (144 +/- 8, 132 +/- 18) and anammox bacteria (281 +/- 8) were the highest in the CW-MFC (Anode). The contents of denitrification, dissimilatory nitrate reduction to ammonium, and electrochemically active bacteria in the CW-MFC (Cathode) were significantly (p < 0.05) higher than others.