Land-use change, soil management, and net CO2 balance of second-crop corn in Brazil

Abstract Corn is Brazil’s second-most cultivated crop (21 Mha). Second-crop corn (SCC) represents 80% of this area and accounts for 8% of global production, making it a promising feedstock for food, feed, and biofuels with reduced land-use change (LUC) pressure. Assessing the net CO₂ balance (NCB) from direct LUC (dLUC) and soil management practices (SMP) is essential to quantify its decarbonization potential. This study provides the first national-level mapping of SCC in Brazil for 2023, including land-use/-cover transitions over the previous 20 and 10 years and associated NCB. SCC expansion over natural vegetation declined from 13% (2003–2023) to 3.6% (2013–2023). The 20-year dLUC NCB ranged from 0.6 to 0.9 t CO 2 ha⁻¹ yr⁻¹, below published values. SMP contributed −0.1 to −0.2 t CO 2 ha⁻¹ yr⁻¹, offsetting ~20% of dLUC. Combined dLUC+SMP NCB for SCC ethanol ranged from 2.3 to 5.3 and 0.3 to 1.5 g CO 2 MJ⁻¹ for the respective periods.