COEFFICIENT OF LINEAR EXTENSIBILITY OF SALT-AFFECTED SOILS AND ITS RELATIONS TO SOIL CHEMICAL PROPERTIES

The coefficient of linear extensibility (COLE) of soils that undergo volumetric changes due to soil moisture fluctuation; is an inherent property that is used to estimate soil extensibility. Many works on the COLE have been performed with fen peat soils, puddled soils and clayey soils; however, there is limited information regarding the COLE of saline-sodic soils. In this study, soil samples were collected from a hard saline-sodic soil region in the Songnen plain, northeast China, to determine the COLE of this soil and its relation to soil chemical properties. The results show that the COLE of the saline-sodic soils varied from 0.044 to 0.201 cm/cm, with an average of 0.117 cm/cm. Moreover, significant correlations (|r| = 0.491-0.793, P < 0.01) were observed between the COLE and soil chemical properties. In addition, the COLE of saline-sodic soils can be predicted on the basis of soil pH, EC and SAR, and 67.2% of the variance in the COLE can be attributed to soil pi I, EC and SAR. This work was carried out to investigate the COLE of saline-sodic soils, which will improve our understanding of the COLE of saline-sodic soils and the relationship between the COLE and soil chemical properties.