2.3 Soil structure
Soil at a depth of 60 cm was sampled before the experiment and subjected to a physicochemical analysis. Some physical and chemical characteristics of the experimental soils are provided in Table 2. The soil had 19.8 kg ha−1 NH4+ nitrogen, 22 kg ha−1 P2O5 potassium and 850 kg ha−1 K2O levels. The soil was alkaline (pH: 7.9) and limy (1.3% CaCO3).