Resumen de Monitoring tridimensional soil salinity patterns at the field scale using electromagnetic induction sensing and inversion

J.L. Gómez Flores, M. Ramos Rodríguez, A. González Jiménez, Mohammad Farzamian, Juan Francisco Herencia, B. Salvatierra Bellido, Pedro Cermeño Sacristán, Karl Vanderlinden

• Continuous monitoring of soil salinity/sodicity is essential in environments such as the B-XII irrigation district (SW Spain) where a shallow saline water table and intensive irrigated agriculture create a fragile equilibrium between salt accumulation and leaching in the topsoil. We evaluate to which extend electromagnetic induction (EMI) sensing and inversion with limited calibration can be used to accomplish such monitoring purposes. EMI surveys were performed in 2017 and 2020 in a field with a heavy clay soil. Soil samples were taken at different locations and depths along a transect and analyzed for salinity/sodicity-related parameters. Inversion of the EMI signals along the transect yielded consistent conductivity images for both years and showed a good relation (R2=0.80) with these parameters. Our results show that inversion of EMI signals offers a powerful means for monitoring spatial and temporal changing soil salinity/sodicity for the specific conditions of the B-XII irrigation district.