Controlled traffic farming maintains soil physical functionality in sugarcane fields

The disorderly machinery traffic has been one of the main causes of soil physical degradation in sugarcane fields. In this sense, the adoption of strategies for machinery traffic control has been a viable alternative to reduce the risk of soil compaction and minimize physical restrictions to plant growth. However, the impact of traffic control on soil physical properties is still unknown in sugarcane fields. In this study, we investigated the impacts of machinery traffic control on soil physical properties and functions under contrasting soil textures (clayey and sandy clay), assessed at row and inter-row sugarcane planting positions. Bulk density, soil porosity, soil pene-tration resistance, the weighted average diameter of aggregates and visual assessment of soil structure (VESS) were measured. In addition, the soil physical quality index (SPQI) was assessed for the following soil functions: support root growth, ability to resist erosion and physical degradation, water supply for plants, edaphic fauna, and its relationship with the exchange of gases between soil and atmosphere. The results revealed that uncon-trolled traffic farming increased bulk density, soil penetration resistance, and VESS scores as well as reduced total porosity mainly in the 0-10 cm soil layer. Controlled traffic farming supported soil functions in relation to uncontrolled traffic. Uncontrolled traffic caused a reduction by 12% on the SPQI at row position in both clayey and sandy clay soils, whereas for inter-row position, no difference was observed between the treatments. Controlled traffic in sugarcane fields was able to reduce soil physical degradation induced by agricultural ma-chinery traffic, whose mitigation of compaction occurs mainly at row-position. These results suggest that controlled traffic farming may be a strategy to reduce soil physical restrictions for root growth in sugarcane fields.