Table 1.
Soil characteristics after 26 years of fertilization treatments in the acidic red soil.
| Treatment | Corn grain yield (kg ha−1) | pH (H2O) | SOCa/g kg−1 | Exchangeable H/cmol(+) kg−1 | Exchangeable Al /cmol(+) kg−1 | Base Saturation /% | ECb/μS cm−1 | Clay (<2 μm) contents / % | Silt (2–20 μm) contents / % |
|---|---|---|---|---|---|---|---|---|---|
| CK | 1064.32 (105.44) c | 5.47 (0.21) b | 8.63 (0.32) c | 0.55 (0.04) a | 0.08 (0.02) b | 92.45 (1.45) a | 42.34 (2.34) c | 30.51 (0.32) a | 47.33 (0.33) a |
| NPK | 2756.44 (174.72) b | 4.15 (0.24) c | 10.65 (0.78) b | 0.53 (0.07) a | 5.57 (0.77) a | 38.50 (2.65) b | 137.56 (4.44) a | 30.58 (0.12) a | 45.43 (0.41) b |
| M | 3652.54 (223.69) a | 6.63 (0.28) a | 16.33 (0.88) a | 0.37 (0.05) b | 0.04(0.01) b | 97.00 (4.23) a | 111.87 (7.81) b | 29.05 (0.23) b | 46.29 (0.53) ab |
The data was showed as average value (n = 3). Standard deviations in parentheses. Results followed by different letters are significantly different at P < 0.05.
aSOC: Soil organic carbon.
bEC: Electrical conductivity.
CK, without fertilization; NPK, chemical NPK fertilizer; M, raw pig manure.