Determination of electrical conductivity of the saturation extract (EC e) relationships with a few soil salinity parameters in comparison the new method of calculating EC e

In this study, relationships of electrical conductivity of the soil saturation extract (ECe) with the ionic composition, the ionic strength and the total dissolved salts are studied in the Sudjan plain; also, the general new method of electrical conductivity calculation that has been presented by McCleskey et al. (2012) is used in order to compare with the proposed equations. Therefore, the 80 soil samples were taken from the Sudjan Plain in Chaharmahal va Bakhtiyari Province and soil salinity parameters by measuring sodium, magnesium, calcium, Potassium, chloride, sulphate, bicarbonate, carbonate, pH and ECe were determined and analyzed. The Pearson’s correlation coefficient at the significance levels 5 and 1 percent between the salinity parameters showed that the carbonate isn’t significantly correlated with other parameters. Also, the correlation of magnesium and ECe was insignificant. The linear model regressions between the ionic composition, sum of ions, cations and anions concentration, ionic strength and total dissolved salts were generalized. The greatest correlation coefficient (0.91) and the lowest root mean square error (0.08 dS m−1) were obtained in the model between the ECe and the ionic composition. The results of research in the studying plain showed that the presented model in this investigation in comparison with the new model of McCleskey et al. (2012) give smaller error and greater correlation. The insignificancy between the carbonate and ECe and the regression models showed that this ion can be neglected in the calculation of ECe.