Unlocking the potential of no-tillage systems: Enhancing soil carbon sequestration and soybean yield with forage grass

Sustainable agriculture relies on practices that boost crop productivity and environmental resilience. No-tillage systems, particularly with cover crops, are promising for improving soil carbon (C) sequestration and agricultural yields. This study evaluates the long-term effects of no-tillage management on soil C storage and soybean yield in Botucatu, SP, Brazil, comparing two cropping systems: forage (Urochloa spp. as a cover crop) and fallow. The experiment, started in 2006, used a randomized block design with eight replicates. Soil samples were collected from the 0-0.6 m depth, and soybean yield was assessed in both the 2006/2007 and 2024/2025 cropping seasons. Changes in soil C stocks and soybean yield increments were calculated by comparing data from these periods. ANOVA and LSD tests (p ≤ 0.05) were used within a 2x2 factorial design, considering two seasons and two crop systems. Significant differences were observed for all parameters, except for soil C stocks and yield in 2006, which were 85.3 Mg ha^-1 and 3.02 Mg ha^-1, respectively. In 2024, both systems showed an increase in soil C, with forage showing superiority over fallow, at 148.23 Mg ha^-1 and 109.35 Mg ha^-1, respectively. Soybean yield also increased for both systems, with forage outperforming fallow, with values of 4.73 Mg ha^-1 and 4.31 Mg ha^-1, respectively. Soil C stock changes and soybean yield increments were higher in forage, highlighting the benefits of no-tillage and Urochloa spp. cover crop for yield and environmental performance.