Table 1. Characteristics of soils used in the study.
| Treatmenta | Soil pH | Total C (%) | Total N (%) | PARb (nmole−1h−1g−1) |
Fertilization (kgha−1y−1)c |
|
|---|---|---|---|---|---|---|
| N input | Ca (dolomite) | |||||
| Standard | 3.36 (0.05) c | 16.86 (1.32) b | 1.23 (0.13) b | 45.91 (5.74) a | 400 | 1000 |
| High Ca | 4.74 (0.10) d | 11.93 (0.13) a | 0.84 (0.04) a | 253.66 (5.10) c | 400 | 3000 |
| No Ca | 2.89 (0.05) a | 19.47 (0.59) c | 1.54 (0.06) d | 55.84 (4.80) a | 400 | 0 |
| High N | 3.09 (0.04) b | 17.82 (0.37) b | 1.52 (0.06) c | 180.18 (17.90) b | 1200 | 1000 |
s.d. are given in parentheses. Values within the same column followed by the same letter are not significantly different at P<0.05.
a
Treatments: standard fertilization (Standard), high-rate Ca fertilizer input (high Ca), no Ca fertilizer input (no Ca) and high-rate N fertilizer input (high N).
b
PAR, potential ammonia oxidation rate (NO2−1 nmole−1 h−1 g−1 dry soil).
c
Dolomite and ammonium sulfate were added to the fields as sources of Ca and N, respectively.