Water-saving driven crop reallocation reduces irrigation energy demand in the mediterranean

Global food insecurity currently affects over 30 % of the world's population, highlighting the need to understand how agricultural systems can be optimized to reduce resource pressures while maintaining productivity. Irrigation is critical for crop production in semi-arid and arid regions such as the Mediterranean, yet it accounts for substantial freshwater use and energy consumption, with associated environmental impacts. In this study, we assess the impacts of crop reallocation on irrigation water, energy demand, and direct CO2 emissions across the Mediterranean. Using a spatially explicit optimization framework integrated with hydrological modelling, we evaluate 32 crops grouped into nine categories, explicitly accounting for irrigation water sources and methods. Our results indicate that optimized crop distributions could reduce irrigation water demand by up to 80 % (70 km3/year), lower energy requirements by up to 85 % (72 × 106 GJ/year), and cut direct CO2 emissions by up to 84 %, without reducing overall food production. Beyond resource savings, we explore the economic and social implications of crop reallocation, noting that less water-intensive crops may be less profitable or culturally less accepted, underscoring the need for supportive policies and incentives. The framework is adaptable to other water-stressed regions, enabling the assessment of trade-offs between water, energy, and carbon under locally specific conditions. By providing a quantitative evaluation of the potential environmental and resource impacts of alternative cropping strategies, this study offers a robust tool for understanding how agricultural systems can be managed to improve sustainability, resilience, and resource efficiency under climate and water constraints.