Amending soils of different pH to decrease phosphorus losses

In most cases the application of Al, Fe and Ca amendments decreased WEP in proportion to the rates applied. However, poor performance was noted when amendments were mismatched to soils altering their pH into the range where high soil P availability was expected. Of the amendments used, alum and iron sulfate were the most cost-efficient. However, even when optimised and applied to critical source areas the estimated cost-effectiveness of these amendments is still poor and may only be effective in the short term.