Acceptability and Evaluation of APSIM-Qryza for Promoting Water and Nitrogen Productivity in Paddy Fields

Abstract

Abstract Aims Crop models are designed to handle the various agronomic complexities that often arise from water and nutrient management in agroecosystems. In paddy fields, irrigation, and nitrogen (N) application are critical factors for achieving adequate yield, but unsuitable strategies can make the environment vulnerable. Methods we parametrized and validated the APSIM-Oryza model using two years experiment under various irrigation techniques (continuous flood (CF) and alternate wetting and drying (AWD) and nitrogen (N) application rates. In addition, two scenarios were run based on a decade of historical weather data. Results The model demonstrated a fit match in calculating aboveground biomass, leaf area index (LAI), and total N uptake over both years. The calculated grain yield from APSIM-Oryza was indicated to closely attach the measured data over parametrization (R2 = 0.92, RMSE = 203 kg ha− 1) and validation R2 = 0.89, RMSE = 308 kg ha− 1). Scenario analysis was recorded the lowest yield, fertilizer recoveries (RE), partial factor productivity (PFP), and agronomic efficiency (AE) was obtained with the basal N application, while the highest physiological efficiency (PE) was achieved. Simulation results showed that under both water management strategies, the highest yield, total N uptake, AE, RE, and partial PFP were observed with 69 (kg N ha− 1) at a split ratio of 5:5. Conclusion The suitable water and N management strategies are able to enhance crop productivity, reduce environmental degradation and increase the efficiency and profitability of food production by addressing water shortages and N loss in farming systems.