Application of time-lapse ERT to determine the impact of using brackish wastewater for maize irrigation

A field experiment was conducted to compare the effects of two irrigation water sources, brackish secondary treated wastewater and surface canal fresh water, on maize crop. During the irrigation cycle, soil water content distribution was estimated by means of time-lapse mode electrical resistivity tomography (ERT), soil electrical resistivity being highly sensitive to soil moisture and water salinity. The effects of the two water sources on the spatial-temporal distribution of ERT-derived soil moisture values were assessed, and different roots' behaviors observed. Results show a decreased root water uptake with brackish irrigation water with respect to fresh water.