Reduction of methane and nitrous oxide emissions from stormwater bioretention cells through microbial electrolytic...

This study investigated the reduction of methane (CH₄) and nitrous oxide (N₂O) emissions from stormwater bioretention cells through microbial electrolytic cell (MEC), showing the largest reduction of 32.21 % (CH₄) at 9.2 μA/m² of current density and 56.16 % (N₂O) at 3.5 μA/m² of current density, compared with the corresponding in the control (0 μA/m² of current density). Kinetic of CH₄ and N₂O emissions could be well fitted by Logistic model with high correlation coefficient (R² > 0.9500) and model efficiency (ME > 0.95) but low relative root mean square error (RRMSE < 7.88). The increase of pmoA and polysaccharide (PS) were responsible for CH₄ reduction, while N₂O reduction was attributed to the decrease of nirS and the increase for nosZ and protein (PN), which could explain the lowest GWP_d (10.67 mgCO₂-eq/m²/h) at 3.5 μA/m² of current density, suggesting that MEC could be promising for the reduction of CH₄ and N₂O emissions from bioretention cells.