Original data-Electrocatalytic Reduction of Nitrate from Paddy Field Drainage Water to Provide Sustainable Ammonium Supply for Rice

Extensive N fertilizer applications and high irrigation water infiltration rates are the main factors causing groundwater NO3--N pollution, posing high risks to the safety of drinking water in remote rural areas. In this study, we effectively constructed a self-made system without external energy inputs to achieve high NO3--N reduction efficiency, as well as high and long-term NH4+-N selectivity. In addition, we proposed a new system to obtain sustainable NH4+-N supplies from paddy field drainage water, providing sufficient N and water supplies for rice at the tillering stage. The pot experiments and the 15N tracing technique revealed increases in the rice yield and NUE, which could be mainly attributed to the sustainable NH4+-N supplies. The obtained results also indicated an enhancing effect of NH4+-N on the rice yield by promoting root growth and development. Our research showed that the utilization of electrochemical technology under rice cultivation can not only reduce NO3--N pollution but also increase rice yields, providing a new method for reducing fertilizer applications and increasing NUEs in paddy fields.