INFLUENCE OF WATER-CONTENT ON ELECTRICAL CONDUCTIVITY OF SOIL

The four-probe system of measuring electric conductivity of soil eliminates the time lag error, but introduces the problem of correcting the changes in conductivity caused by water content. Units were constructed and samples prepared to evaluate the influence of water content, and salt concentrations on the four-probe conductivity (K4P). Two soils were studied. Regression equations developed to estimate saturation or 1:5 extract electric conductivity from four-probe conductivity and water content gave correlation coefficients of 0. 75 and 0. 90, respectively.