Water footprint of globe artichoke: The impact of evaporative canopy-cooling irrigation

Climate change and the increasing frequency of heatwaves represent major challenges for agriculture. Innovative cooling irrigation techniques can mitigate their adverse effects by enhancing growth rates and earliness, although often at the expense of a higher water consumption. This study assessed the agronomic impact of evaporative canopy-cooling irrigation management on globe artichoke ( Cynara cardunculus L. var. scolymus ) by using a water footprint approach to relate the actual water consumption to the yield. Field trials were carried out over three growing seasons of the cultivar “Spinoso sardo”, grown in the Mediterranean region of Sardinia (Italy) using a forcing cultivation technique. Canopy-cooling was applied using an automatic micro-sprinkler system when daily air temperature exceeded 25 °C and humidity fell below 70%. The canopy-cooling management reduced heat stress, decreasing head atrophy incidence by averagely 57% compared to the drip-irrigated control. Canopy-cooling did not affect the water footprint because the higher water consumption (+15%) was compensated by proportionally higher yields (+20%), with an average water footprint of 888 m³ t⁻¹ . The blue water footprint weighted averagely 64% in both irrigation managements. The positive effects of canopy-cooling on yield were statistically significant only under severe heat stress, particularly during the inflorescence formation stage, leading to an increase of first-order heads. The water footprint analysis highlighted the importance of assessing the agronomic impact of irrigation by shifting from minimizing water use to maximising the yield per unit of water consumed, and of developing irrigation strategies to cope with climate change scenarios in Mediterranean horticultural agroecosystems.