Atacama Desert: water resources and reuse of municipal wastewater in irrigation of cut flower aeroponic cultivation system (first laboratory experiments)

Reuse of Treated Municipal Wastewater from Constructed Wetlands for Cut Flowers Irrigation in Aeroponic Cultivation

“…Finally, regarding the nutritional requirements of Lilium regarding the macronutrients nitrogen and phosphorus, this is a plant that does not require large amounts of phosphorus, so the concentration reported in table 1 would be sufficient for its development [33]. Regarding nitrogen, Vera-Puerto et al [5] indicated that the relationship between the forms of TN present in the treated wastewater (ammonium and nitrate) would not have adverse effects on the development of Lilium. Table 2 presents the variation of pH and EC on days 0, 3, and 7 in the irrigation water of each experimental unit (EU-1, EU-2).…”

“…Among the different sources, the reuse of treated effluents from wastewater has been explored as an alternative under these and other climatic conditions [2], [3]. However, the total percentage of treated water reused in the Atacama Desert does not exceed 10 % [4], [5], unlike other arid zones, where the percentage can exceed 70 % [6].…”

“…The low percentage of wastewater treated and reused in the Atacama Desert can be explained by several reasons. First of all, the location of the largest urban centers (Arica, Iquique, Antofagasta, La Serena-Coquimbo) on the shores of the Pacific Ocean, and the decision of the country to use submarine outfalls as a wastewater disposal system [3], [5]. A second reason is the natural geological condition that causes the salt content in soil and water to have values of 26 dS/m and 2 dS/m, respectively [2], [7].…”

“…A second reason is the natural geological condition that causes the salt content in soil and water to have values of 26 dS/m and 2 dS/m, respectively [2], [7]. The third reason is associated to ignorance and disinformation on the potential users and beneficiaries of reuse [5]. Finally, there is also an associated factor in the form of low treatment coverage in decentralized or rural areas, with no official figures for the Atacama Desert, but it is estimated that coverage at the country level in Chile, does not exceed 20 % [4].…”

Water reclamation and reuse

“…At three different HRTs (1.9, 1.4, and 1.0 day), 15 different plant species were tested, and all effluents met the standards for various reuse applications according to Spanish Legislation and Europe draft for water reuse (Zraunig et al, 2019). Municipal wastewater treated by wetlands in the Atacama Desert demonstrated their efficacy in water reuse for cultivating cut flowers using a lab‐scale aeroponic cultivation system under extremely arid conditions (Vera‐Puerta, Olave, Tapia, & Chavez, 2019).…”