Data1_BenMosheetal_HESS (.xlsx): data of the raw spexrta presented in Fig.2 Data2_BenMosheetal_HESS (.xlsx): data from the homogeneous, heterogeneous experiments, and the Zn and Ca experiments in sand. SIPBTC_Ca (folder) + .h1 file: model files for hydrus-based calibration of the SIP data. Homo_main.m: a MATLAB code that takes in raw SIP records (phase and impedance) and calculates the real and imaginary conductivity. This file needs 'CaBTC02_Main_time.xlsx' to run. Before running the code, users should enter the directory path for the folder that contains both the .m file itself and the .xlsx data file.