Table 2 Total P (TP E ) and organic P (OP E ) in soil extracts (mg kg −1 ) and relative distribution of P
From: Optimized procedure for the determination of P species in soil by liquid-state 31P-NMR spectroscopy
P species | Phos-P | Orth-P | Monoesters | PL | DNA | Diesters a | Pyro-P | Poly-P | OP E | TP E |
|---|---|---|---|---|---|---|---|---|---|---|
ppm intervals | 18 to 24 | 5.6 | 5.3 to 3.3 | 1.6 to −0.3 | 0.8 | −1.1 to −1.6 | −4.6 | −19 to −21 | ||
Farmland soil | ||||||||||
Freeze-drying | 0.5 | 116.7 | 14.7 | 0.6 | 1.0 | 1.6 | 0.2 | 0.1 | 16.8 | 133.8 |
Air-drying | ND | 106.1 | 7.8 | 0.5 | 0.3 | 0.9 | 0.2 | 0.1 | 8.8 | 115.1 |
Fresh | 1.4 | 98.7 | 8.4 | 0.9 | 0.3 | 1.1 | 0.2 | 0.1 | 11.0 | 109.9 |
Farmland soil added with compost | ||||||||||
Freeze-drying | 0.5 | 160.3 | 16.0 | 1.7 | 1.4 | 3.2 | 0.4 | 0.2 | 19.9 | 180.7 |
Air-drying | 0.5 | 153.7 | 8.6 | 0.3 | 0.2 | 0.4 | 0.1 | 0.7 | 10.3 | 164.1 |
Fresh | 0.3 | 153.8 | 12.8 | 1.6 | 0.6 | 2.2 | 0.8 | 0.7 | 16.0 | 170.5 |
Forest soil | ||||||||||
Freeze-drying | 4.1 | 172.0 | 74.8 | 3.0 | 2.5 | 5.5 | 0.9 | 0.4 | 84.9 | 257.9 |
Air-drying | 4.5 | 159.1 | 70.7 | 2.0 | 2.1 | 4.1 | 1.0 | 0.2 | 79.5 | 239.7 |
Fresh | 5.2 | 127.8 | 52.7 | 1.2 | ND | 1.2 | ND | 2.0 | 61.1 | 188.9 |
Forest litter | ||||||||||
Freeze-drying | 8.1 | 38.6 | 80.3 | 2.6 | 6.7 | 9.4 | 2.5 | 1.4 | 97.1 | 140.2 |
Air-drying | 7.8 | 31.0 | 83.4 | 1.9 | 6.0 | 7.9 | 2.5 | ND | 99.1 | 132.7 |
Fresh | 3.3 | 46.2 | 80.6 | 2.1 | 4.9 | 7.0 | 1.2 | 1.0 | 91.9 | 139.4 |