Enhanced nitrogen removal in an electrochemically coupled biochar-amended constructed wetland microcosms: The interactive effects of biochar and electrochemistry

Abstract The interactive effects of both biochar (BC) and electrochemistry (EC) can affect nitrogen (N) removal process. However, little is known about how this function in constructed wetland (CW) systems. In this study, an electrochemically (EC) coupled BC-amended saturated subsurface vertical flow constructed wetland (BECW) systems were established to enhance nitrogen (N) removal. Other three CW systems: without BC and EC (CW); with EC only (ECW); and with BC only (BCW) were performed as controls. Results indicated that the total nitrogen (59.88%–93.03%) and nitrate‑nitrogen (83.14%–100%) of the BECW system were significantly enhanced (p