Phosphate sorption characteristics of sugarcane soils in the Ingham area

When fertilisers containing phosphate are applied to soils, most of the phosphate is retained or sorbed by the soil constituents and relatively little remains in the soil solution. It is important that not only the amount of phosphate directly available to crops in the soil solution be measured, but also that the relationship between the amount of phosphate added to the soil as fertiliser and the amount entering the soil solution be characterised. The problem of characterising the relationship between adsorbed (added) phosphate and soil solution phosphate is solved by determining the P sorption isotherm of the soil.