Can saltland pastures lower the water table and reduce salinity ?
Yes, in some situations. In low relief landscapes such as those found in the eastern wheatbelt, groundwater movement is often vertical (rise and fall), other than lateral (sideways movement). This means that when deep rooted perennials (such as saltbush) are planted in valley floors, they not only reduce in situ recharge, but in some circumstances will use saline the groundwater. The degree to which saltbush can use groundwater will be affected by the salinity, pH and presence of toxic ions in the groundwater. Also saltbush will use non-saline water (from annual rainfall) before it uses saline groundwater. At present we expect some use of groundwater in summer at salinities up to about sea-water concentrations. However, saltbushes may die if the groundwater is highly acid (pH values around 4) with toxic concentrations of dissolved aluminium.
