ABSTRACT
Soils in numerous areas of the world are adversely a¦ected by the presence of excess Na in the soil solution and as an exchangeable cation. For example, it is estimated that ∼50% of the arable land in Australia su¦ers from sodicity-related problems (Naidu, 1993). Sodium-a¦ected soils exhibit poor soil water and air relations that adversely a¦ect water movement in the soil, root growth, and plant production, and make the soil di¬cult to farm when either dry or wet. Consequently, in many cases, such soils have had to be abandoned.
