Table 6 The N-P-K balance for wheat crops.
N-P-K flows (Mg) | N | P | K |
|---|---|---|---|
Outputs | |||
Harvests (Ho) | 12 843 | 2 213 | 2 819 |
Cropped or grazed straw (So) | 5 917 | 1 084 | 4 386 |
Cropped or grazed weeds - crops (Wo) | 7 194 | 681 | 4 845 |
Leaching and runoff (Lo) | 4 845 | 0 | 1 714 |
Erosion (Eo) | 0 | 1 541 | 1 164 |
N emissions (Vo) | 8 023 | 0 | 0 |
Sum | 38 822 | 5 519 | 14 928 |
Inputs | |||
Seeds (Si) | 1 376 | 237 | 302 |
Manure (Mi) | 8 558 | 1 666 | 4 202 |
Field excretions (Ei) | 3 232 | 531 | 1 644 |
Other biomass entries (Bi) | 728 | 116 | 972 |
Chemical fertilizers (Fi) | 12 437 | 13 210 | 590 |
Rainfall (Ri) | 3 445 | 171 | 1 388 |
Soil weathering (Wi) | 0 | 857 | 6 352 |
Symbiotic N fixation - wild legumes (LWi) | 2 302 | 0 | 0 |
Non-symbiotic N fixation (Oi) | 1 714 | 0 | 0 |
Sum | 33 792 | 16 789 | 15 548 |
Balance | |||
(Mg) | −5 030 | 11 270 | 620 |
(kg.ha−1.yr−1) | −5,9 | 13,2 | 0,7 |
