Influence of banded fertiliser on the chemical environment surrounding the band. II. Effect on soil‐solution cations, cation—anion balance and solution phosphorus

The influence of several banded fertilisers on soil solution content of Ca, Mg, K, P and on cation‐anion balance at two distances from the band was studied. Treatments consisted of various combinations of monocalcium phosphate (MCP), KCl, NH 4 NO 3 , (NH 4 ) 2 HPO 4 and urea applied on a nutrient element basis of 22.4 or 67.2 kg/ha. Ammonium nitrate or KCl, supplied separately, produced the highest solution concentrations of Ca (up to 1200 parts/million) and Mg (up to 500 parts/million). Solution concentration of Ca and Mg increased over a 32‐day incubation time near treatments containing urea. Treatments containing (NH 4 ) 2 HPO 4 initially reduced solution Ca and Mg contents only when applied at 67.2 kg/ha. All treatments not containing K had similar but smaller effects on solution K than they did on Ca and Mg. Highly significant correlations were obtained between total mequiv. of Ca+ Mg and NO 3 for treatments containing urea or (NH 4 ) 2 HPO 4 , while low or non‐significant correlations resulted from NH 4 NO 3 treatments. Treatments containing (NH 4 ) 2 HPO 4 and MCP yielded soil solution P concentrations as high as 1000 parts/million. Urea combined with (NH 4 ) 2 HPO 4 or MCP drastically reduced solution P concentrations.