Comparison of surface properties of synthetic and soil struvite

Abstract

Baugé, S. M. Y., Lavkulich, L. M., Wilson, J. E. and Schreier, H. E. 2014. Comparison of surface properties of synthetic and soil struvite. Can. J. Soil Sci. 94: 169–176. X-ray, Raman and nuclear magnetic resonance (NMR) analyses of intensively managed agricultural soils in southwestern British Columbia reported the presence of the Mg-phosphate mineral, struvite. Soils are heterogeneous, thus analytical techniques based on single minerals require calibration in order to provide reliable results. A synthetic struvite was used to compare the properties of the soil phosphate with struvite. The results confirmed the presence of struvite and possibly additional species of Mg. Time of flight–secondary ion mass spectroscopy (TOF-SIMS) revealed that the surface of struvite, to 2nm depth, is dominated by Mg with other cations, notably Fe and NH4 that were measured in minor amounts and were associated with the Mg rich surface layer. The results suggest that P is located within the struvite structure. Chemical reactions of struvite and phosphorus chemistry in these soils appear to be governed by the Mg surface layer.