Soil responses to sodicity and salinity: challenges and opportunities

Abstract

Exchangeable sodium and low salinity deteriorate the permeability of soils to air and water. The susceptibility of soils to sodicity and low salinity depend on both the inherent properties of the soils (e.g. texture, mineralogy, pH, CaCO₃, sesquioxides, and organic matter content) and extrinsic, time-dependent properties (e.g. cultivation, irrigation method and wetting rate, antecedent water content, and the time since cultivation). Whereas the effect of inherent soil properties on the soil response to sodicity has been studied and modelled, especially under laboratory conditions, the effect of soil management on the physical response of soils to sodicity has been studied very little. Consequently our ability to predict the changes in soil permeability under field conditions is limited. Including the effect of management on the physical response of soils to sodicity and low salinity is the main challenge facing researchers, consultants, and farmers.