عنوان مقاله [English]
نویسندگان [English]چکیده [English]
Salinity and sodicity are expressed in a number of ways, depending on the method and purpose of the measurements. Some researchers attempt to estimate the parameters which can be time consuming, expensive and linked with error from easy- to- obtain parameters. However, these relationships are not universal and, may also vary depending on the type of soil. The aim of this study was to find simple equations in order to estimate the salinity and sodicity parameters for the salt-affected soils of Tabriz plain. For this purpose 30 composite soil samples were taken from the area. According to the results, salinity (TSS, ionic strength and concentration of chloride and sodium ions) and even sodicity (SAR and ESP) parameters are in close relation with the ECe. The following equations are proposed for estimating parameters of ionic strength (mmol L-1) TSS (mmolc L-1) and SAR (mmol L-1 )0.5 from ECe(dS m-1): I=19.1 ECe ( R2=0.991 ,SEE=57), TSS=7.56 ECe1.13 (R2=0.994 ,SEE=3.9) and SAR= 1.44 ECe0.925 (R2=0.916 ,SEE=11.3) .The data showed that there is a significant positive relationship between pH of saturation extract (in contrast to pH of saturation paste) and bicarbonate concentration. Moreover, this pH may be greater or lower than the pH of saturation paste, depending on the degree of salinity.