Table 5. Functional classes of phosphorus compounds in a second extraction with a solution containing 0.5 M NaOH and 50 mM EDTA in the revised fractionation procedures detected by ³¹P-nuclear magnetic resonance spectroscopy (-0.31 to 6 represent the chemical shift, ppm; percentage of P forms of total P in parentheses).

Manure types	Inorganic P		Organic P
	Orthophosphate	Pyrophosphate	Orthophosphate monoesters									Orthophosphate diesters
	6	−4.53	5.8	5.63–5.10	5.07	4.86	4.75	4.49	4.38	4.25–3.94		1.32	−0.31
						g P kg−1 (% of P in extracts)
Dairy manure	1.48 (20%)	ND	0.11 (1%)	ND	0.12 (2%)	0.23 (3%)	0.14 (2%)	0.21 (3%)	0.13 (2%)	ND		ND	0.074 (1%)
Swine manure	8.84 (27%)	0.15 (0.5%)	2.09 (6%)	0.92 (3%)	ND	3.7 (11%)	ND	3.6 (11%)	1.9 (6%)	ND		ND	ND
Broiler litter	2.02 (13%)	0.085 (0.5%)	0.79 (5%)	0.82 (5%)	0.11 (1%)	1.42 (9%)	0.55 (3%)	1.62 (10%)	0.78 (5%)	0.28 (2%)		0.027 (0.2%)	ND

Note:

ND: not detected.

-0.31-6: the chemical shift, ppm; percentage of P forms of total P in parentheses.