Water footprint of ‘Gigante’ cactus pear with deficit irrigation using wastewater and blue water plus cattle manure

Abstract

This study aims to evaluate the water footprint of cactus pear cultivated under different irrigation strategies. Treatments were: no fertilization and no irrigation (T1); no fertilization and deficit irrigation (DI) with wastewater (0.6 L plant-1 week-1) (T2); no fertilization and DI with wastewater (1.2 L plant-1 week-1, once a week) (T3); no fertilization and DI with wastewater (1.2 L plant-1week-1, divided in two weekly applications) (T4); with organic fertilization (60 Mg ha-1 of bovine manure) and DI with blue water (1.2 L plant-1 week-1) (T5); and with organic fertilization (60 Mg ha-1 of bovine manure) and no irrigation (T6). Treatments were arranged in a completely randomized blocks design, with five replicates. Productivity, nutrients applied and consumption of green and blue water were evaluated. The water footprint was lower in treatments irrigated with wastewater than in the other treatments. The DI, using blue water, makes it possible to increase crop productivity without increasing water footprint; in the absence of irrigation, organic fertilization does not reduce the water footprint; the DI, using wastewater, makes it possible to increase crop productivity while decreasing water footprint.