Modeling the impacts of climate-smart practices on soil–water interaction and wheat yield under climate change in central Ethiopia

This study aimed to model the impact of climate-smart agricultural (CSA) practices on soil‒water balance, water use efficiency (WUE_ET), and wheat yield in the face of climate change. The AquaCrop version 7.1 model was used to estimate the water balance and yield under the baseline (1981-2010) and future (2050s, RCP4.5) climate scenarios. We evaluated five CSA practices, varying in tillage, residue management, and water management, based on experiments conducted in 2020 and 2021. Observed data on wheat (Triticum aestivum L.) grain yield and surface runoff were used for model calibration (2020) and evaluation (2021). The model was evaluated using four performance indicators and found to be robust. The treatments included farmers' conventional practices (CPs), soil bunds (SBs), crop residues (CRs), integrated conservation practices (ICPs), and berken plows (BPs). The results show that climate change is likely to reduce grain yield and WUE_ET under CP by 1% and 16.3%, respectively, by 2050 compared to the current 2021 period. All CSA practices studied increased grain yield and WUE_ET over the CP in both periods. Under future climates, ICP showed a greater relative grain yield (Y = 4.51 t/ha), water use efficiency (WUE_ET = 1.32 kg m³), and other soil water balances, followed by CR, BP, and SB over CP. Overall, ICP has shown tremendous potential for climate change adaptation among the other CSA practices tested. Therefore, adaptation to future climate conditions must integrate different practices, and the novel ICP can be promoted as a climate-smart practice in similar farming systems and agro-ecological settings.