A Simple Methodology For Determining Electrical Conductivity of Soils

Abstract

Electrical conductivity of soils has been demonstrated to be an important parameter for determining their basic properties. As measurement of soil conductivity using the DC field is limited by irreversible changes in the state of the soil and the errors due to electrode polarization, application of an AC field has been recommended. However, it has been noted that researchers have resorted to the ‘single frequency measurements’, considering that impedance is purely resistive, which may not always be true. Hence, it becomes essential to study electrical conductivity of soils in a broad frequency range. With this in view, using the concept of Impedance Spectroscopy (IS), conductivity measurements were carried out on different type of soils in the 20 Hz to 1 MHz frequency range, and details of the study are presented in this paper. Measured data has also been analyzed using Nyquist and Bode formats, and a good matching of the results has been noted. This demonstrates utility of the developed methodology and the ease with which electrical conductivity of soils can be determined in the laboratory.