
%0 Journal Article
%A Gilkes, RJ 
%A Mangano, P 
%T Poorly soluble, iron-aluminium phosphates in ammonium phosphate fertilizers: Their nature and availability to plants
%J Soil Research
%D 1983/06/01
%V 21
%N 2
%P 183-194
%K 
%R https://doi.org/10.1071/SR9830183
%U https://www.publish.csiro.au/paper/SR9830183 
%X Both monoammonium and diammonium phosphate fertilizers contain various (Ca,Mg)(NH4)- (Fe,Al)(PO4)(F,OH)H2O compounds that are insoluble in water and comprise 4.9-9.9% of the total phosphorus content of the fertilizers. The compounds have been isolated and characterized by chemical, X-ray powder diffraction, ix., and thermogravimetric techniques. The compounds are only 35-60% as effective as monocalcium phosphate (MCP) in supplying phosphorus to wheat grown under glasshouse conditions. The residual effectiveness of the compounds for a second crop of wheat was generally lower (10-20% relative to freshly applied MCP) than the residual value of MCP (20 %). 
