Is the Subsurface Drip the Most Sustainable Irrigation System for Almond Orchards in Water-Scarce Areas?

The expansion of irrigated almond orchards in arid and semi-arid areas with scarce water available raises key issues related to the sustainability resources. A 3-year field experiment was conducted on a commercial young orchard located southeast Spain study effect two drip irrigation systems (surface, DI subsurface, SDI) crop growth their physiological responses under fully-irrigated conditions. Crop evapotranspiration (ETc) its components (crop transpiration, Tc soil evaporation, Es) were monitored as well nitrogen productivities. To estimate ETc, simplified two-source energy balance (STSEB) approach used. Although lower amount applied SDI compared (differences between 10% 13.8%), yield kernel showed no significant differences. ETc estimates resulted small differences for spring fall periods (0.1–0.2 mm day−1) both treatments, while during higher ETo (May–August), being 1.0–1.3 day−1 treatment than treatment. productivity (IWP) significantly However, treatments observed productivity. It can be concluded that system is suitable strategy irrigating crops, reducing consumptive use increasing IWP.