Table 1.
The properties and soil labile organic carbon fraction contents of soil samples tested before cultivation in 2020.
| RTO | RT | PT | NT | |
|---|---|---|---|---|
| SOC (g·kg−1) | 14.18 ± 0.17 c | 14.49 ± 0.11 b | 15.52 ± 0.04 a | 13.75 ± 0.06 d |
| TN (g·kg−1) | 1.65 ± 0.04 b | 1.62 ± 0.03 b | 1.74 ± 0.03 a | 1.65 ± 0.03 b |
| AHN (mg·kg−1) | 120.60 ± 0.76 a | 112.08 ± 4.26 b | 115.29 ± 6.22 ab | 111.07 ± 2.65 b |
| AP (mg·kg−1) | 27.34 ± 0.33 c | 35.88 ± 0.68 a | 28.08 ± 1.07 c | 32.30 ± 0.50 b |
| AK (mg·kg−1) | 178.28 ± 5.53 b | 180.24 ± 2.21 b | 212.88 ± 9.00 a | 184.66 ± 6.63 b |
| MBC (mg·kg−1) | 91.16 ± 6.11 c | 98.48 ± 0.72 b | 101.99 ± 10.08 ab | 105.55 ± 9.54 a |
| DOC (mg·kg−1) | 39.41 ± 1.75 d | 47.91 ± 1.52 b | 52.41 ± 0.65 a | 42.47 ± 1.91 c |
| EOC (g·kg−1) | 1.98 ± 0.13 c | 1.87 ± 0.11 c | 3.09 ± 0.16 a | 2.21 ± 0.01 b |
| LA | 16.29 ± 1.47 c | 14.84 ± 1.11 c | 24.91 ± 1.64 a | 19.12 ± 0.08 b |
| pH | 5.70 ± 0.07 a | 5.35 ± 0.04 b | 5.20 ± 0.01 c | 5.46 ± 0.13 b |
Notes: The significant differences between treatments are indicated by different lowercase letters labeled after the same column of data (p < 0.05). AHN = alkaline hydrolyzable nitrogen, AP = available phosphorus, AK = available potassium. MBC = soil active microbial carbon, DOC = dissolved organic carbon, EOC = easily oxidized organic carbon, and LA = soil organic carbon instability.