Fig. 6. Solution ³¹P nuclear magnetic resonance (NMR) spectra of alkaline extracts of cattle manure extracted with different concentrations of NaOH (0.15, 0.25, and 0.50 M), and a constant concentration of 50 mM EDTA. The main spectra are plotted using a line broadening of 4 Hz, while inset spectra are plotted using line broadening of 1 Hz for the 0.15 M NaOH + 50 mM EDTA extract, 2 Hz for the 0.25 M NaOH + 50 mM EDTA extract, and 4 Hz for the 0.50 M NaOH + 50 mM EDTA extract. The main spectra are scaled to show the largest orthophosphate monoester signal as 75% of the full height of the figure.