Sustainable irrigation strategies for enhanced rice yield and economic sustainability

Abstract Water scarcity is a growing challenge for sustainable agriculture, particularly in water-intensive crops like rice. This study evaluates the impacts of three irrigation methods; drip irrigation (DI), alternate wetting and drying (AWD), and continuous flooding (CF) on rice yield, water productivity and economic returns over three years. Two irrigation levels (I1: Application of water equal to 25 % of the water between the saturation point and field capacity when the soil moisture was near field capacity, I2: Application of water to field capacity when 25 % of the available water holding capacity was depleted) were applied. Results revealed that irrigation methods and levels significantly influenced rice yield at the 1 % level. The highest average yield (7.95 t /ha) was obtained from CF, followed by AWDI1 (7.60 t /ha) and DI1 (6.39 t /ha). Drip irrigation and AWD reduced water use by 30–57 % compared to CF but resulted in yield losses of 2–52 %. However, the AWDI1 treatment recorded the highest water productivity and net income (US$2455 ha), outperforming CF and DI1. Economic analyses confirmed the viability of AWD and drip irrigation as sustainable alternatives to CF, balancing water conservation with profitability. These methods are particularly effective in regions with limited water availability, offering a sustainable approach to rice cultivation without significant trade-offs in yield quality. This study also underscores the importance of integrating physical and economic indicators when selecting irrigation strategies to ensure food security and resource sustainability in the face of water scarcity.