This study has been developed in an irrigated alluvial aquifer in the semi-arid zone of Brazil (State of Pernambuco). The objective was to investigate the effect of different leaching depths and precipitation on reducing soil salinity in drainage lysimeters. Based on numeric simulations using the HYDRUS-1D model, flow and salt transport in the unsaturated zone were evaluated. By using measured actual evapotranspiration and precipitation, it was verified that the model is a satisfactory tool to simulate flow and transport in the studied situations considering different leaching depths. Numerical and experimental results pointed out that the partial leaching could be used for reduction of the salinity in the root zone, as far as effective precipitation might complement the leaching process.
semiarid; salinity; alluvial aquifer