The Effects of Different Irrigation and Field Management Practices Using AquaCrop Model on Yield and Water Productivity

Abstract

World population is prospected to increase to 9.8 billion people in 2050 and global food and water demands can also be presumed to rise concurrently. Regarding these future demands and considering climate change and depletion in water sources; new approaches, management strategies, and models are needed. In this study, the AquaCrop model, which may simplify the complexities of the real-system assessments, is used as an analytical tool to predict the effects of different management practices within winter wheat, spring wheat, winter barley, and maize in a specific location (middle Guadiana sub-catchment, Spain). The primary drivers from the model were determined as actual evapotranspiration (ET a ), yield (Y), and water productivity (WP). Model runs were executed within three different management strategies; which are irrigation technologies, irrigation strategies, and mulching practices. Thereafter, the yield gaps (Y g ) and water productivity gap (WP g ) were analyzed, and water scarcity/shortage degrees were compared. The results of this study showed that the AquaCrop model is a sophisticated model to estimate ET a , Y, and WP parameters. Yield productions in deficit irrigation were mostly more than supplementary irrigation. Full irrigation showed the highest yield within non-limited water conditions; however, some adverse effects of the full irrigation strategy such as salinity should not be ignored. Mulching practices positively affected the ET a reduction. Full irrigation and no mulching scenario showed the worst impacts on the water resources system. Supplementary irrigation and synthetic mulching practices depicted the least surface water resource deterioration. Deficit irrigation and synthetic mulching practices resulted in remarkable water savings with fewer yield losses compared to the scenario with the highest yield production levels.