Effect of subsoiling depth on soil physical properties and summer maize (Zea mays L.) yield

Abstract

The present study was carried out in 2016–2017 to assess the effect of subsoiling depth on the soil bulk density, stability of soil structure, soil physical properties and summer maize yield based on a field experiment started in 2015. Four tillage depths were studied: conventional tillage 25 cm (CT₂₅); subsoiling tillage 30 cm (ST₃₀); subsoiling tillage 35 cm (ST₃₅) and subsoiling tillage 40 cm (ST₄₀). The results showed that at the 20–50 cm depth ST₃₀, ST₃₅and ST₄₀ decreased the mean soil bulk by 4.59, 7.13 and 8.27%, respectively, and at the 0–40 cm depth reduced soil compactness by 17.62, 23.63 and 36.42%, respectively, as compared to CT₂₅. ST₄₀ reduced soil compactness in the 0–40 cm soil layer under conditions of relative drought (during the maize season growing season of 2016), ST₃₅ and ST₄₀ increased macroaggregates (> 0.25 mm), improved the stability of the aggregate structure (geometric mean diameter and mean weight diameter) (20–40 cm), increased soil water storage capacity at 40–60 cm and increased maize yield by 7.89% and 8.91%, respectively. Considering the improvement of soil properties and crop yield, ST₃₅ was the optimum method to increase maize yield and modulate soil physical properties in the North China Plain.