Assessing the Impact of Cropping Scenario Adjustments on Irrigation Water Allocation Efficiency

Given Taiwan’s unique topographical challenges, erratic spatial and temporal rainfall distribution, and extreme climatic conditions, effective irrigation water allocation and sustainable utilization of water resources pose significant constraints. The current dilemma of rice overproduction and low grain self-sufficiency underscores the urgent need for irrigation water management and water resources planning researchers to address these issues through refined crop farming methods and irrigation systems. The purpose of Evaluating adjustments to the double-cropping system and implementing the government’s four-selection-three-crop strategy, the research aimed to analyze their impact on irrigation water consumption, water-saving efficiency, and water resource productivity. This research shows that the cropping scenarios significantly influence the field irrigation requirement and water-saving efficiency (A-1 to A-4). Under scenarios A-2 and A-3, the field irrigation requirement substantially saves 23% to 28%. Water productivity for the first and second paddy rice and the upland crop ranges from 10.73 to 11.39 NT/m3, 9.91 to 12.45 NT/m3, and 33 to 193 NT/m3, respectively. The study suggests transitioning to alternative crops as a water-efficient strategy, considering food security and economic benefits.