Table 2.
Soil organic carbon, total nitrogen, and mineral nitrogen averaged across soil layers, as affected by tillage and cropping system in 2014 in the mother trial.
| Cropping system |
||||
|---|---|---|---|---|
| Tillage system | Sole maize | SB–MZ | SB/MZ | Mean |
| Organic carbon (g kg-1) | ||||
| CT | 3.42aA | 4.26bA | 4.82acA | 4.17A |
| MT | 4.14aB | 5.29aA | 4.52aAB | 4.65A |
| NT | 5.40aAB | 5.39bA | 5.20bcB | 5.33B |
| Mean | 4.32a | 4.98b | 4.85b | |
| Total nitrogen (g kg-1) | ||||
| CT | 0.37aA | 0.41bA | 0.43bA | 0.40A |
| MT | 0.54aA | 0.62bA | 0.64bA | 0.60B |
| NT | 0.59aA | 0.71bA | 0.66bA | 0.65B |
| Mean | 0.50a | 0.58b | 0.58b | |
| Mineral nitrogen (mg kg-1) | ||||
| CT | 20.3aA | 26.6bA | 24.0bA | 23.6A |
| MT | 40.5acA | 33.8bB | 32.2cA | 35.5B |
| NT | 35.1aA | 51.1bcB | 47.4cA | 44.5C |
| Mean | 31.9a | 37.2a | 34.5a | |
CT, conventional tillage; MT, manual tillage; NT, no-tillage; CMZ, continuous maize;
SB–MZ, soybean–maize rotation; SB/MZ, soybean/maize intercrops.
Means within a column followed by similar upper case letters are not significantly different.
Means within a row followed by similar lower case letters are not significantly different.