Calibration of Inductive Electromagnetic Meter for Determining Electrical Conductivity in Vertisols

Significant positive correlation found between inductive electromagnetic meter (IEM) readings and saturated paste extract electrical conductivity (ECe) revealed that this technique can precisely be used for determination of bulk soil salinity. The calibration equations developed elsewhere do not hold good for the black soils of Upper Krishna Project (UKP) command. Multiple regression equations developed through calibration of the instrument for black soils of the command are precise and reliable as revealed by significant positive correlation between predicted and observed soil salinity. Co-efficient of determination (R²) between predicted and observed random sets of the samples ranged between 0.79 and 0.89.