Comparative Evaluation of Methods for Estimation of Soil Salinity

Abstract

Different methods to estimate electrical conductivity (EC) of saturated soil paste extract (ECe) of 1:2 and 1:5 soil: water suspensions were evaluated. Soil samples were taken from different depths (viz. 0-15, 15-30, 30-45, 45-60, and 60-90 cm) of the wheat field under irrigated saline regimes ranging from 1.5 to 12 dSm-1. The relationship between the electrical conductivity of saturated paste extract (ECe) and soil-water suspension extracts (i.e., EC1:2 and EC1:5) was established beside the development of regression models and conversion factors. Regression models relating ECe with EC1:2, EC1:5 were developed with coefficients of determination (R2) 0.98 and 0.99 respectively. The average conversion factor between ECe~ EC1:2 and ECe~ EC1:5  were 2.7 and 7.7, respectively. Methods standardized in the study can be used to estimate the EC of different saturated soil paste extract ratios, which will be less cumbersome and significantly reduce the estimation time.