Atacama Desert: Water resources and reuse of municipal wastewater in irrigation of cut flower aeroponic cultivation system (first laboratory experiments)
Vera-Puerto, Ismael L.
This work aims to evaluate the cultivation of cut flowers irrigated with treated wastewater in a soilless cultivation technique such as aeroponics in arid climates. In addition, information about the state of water resources in the Atacama Desert, focusing on the wastewater management, is showed to explain the context where this study was developed. In this arid environment, two experimental aeroponic units were planted with the cut flower Lily Tresor. For irrigation, municipal wastewater treated by treatment wetlands was used. Moreover, the water resource information of the Atacama Desert was analyzed. Thereby, in the Atacama Desert average annual rainfall is 87 mm/year, and agriculture represents 72% of the total used water (10.29 m3 /s). Furthermore, less than 10% of the treated municipal wastewater is reused despite the treatment coverage close to 100%. Meanwhile, the Lily Tresor was developed under the experimental conditions, but its commercialization would be limited to national markets, because height (stem length) is less than 0.65 m. In this regard, the electrical conductivity (>2,300 µs/cm) in irrigation water and luminosity (>38 klux) were factors that affected the growth of Lily Tresor. Finally, between 10% and 20% of the water for producing Lily Tresor in comparison with other cultivation systems was used. This result shows the efficient water use by the aeroponic cultivation system. Thus, the cut flowers production in soilless cultivation systems such as aeroponics under extreme arid conditions and irrigated with treated municipal wastewater is possible. However, for industrial scaling, improvements in water and luminosity management must be done.