USE OF DESALINATION BRINES IN THE CULTIVATION OF HALOPHYTES: A VISION OF CIRCULAR ECONOMY

Resumen

Water scarcity and distribution constitute a problem driven by population growth and industrial overexploitation. To secure water supply, desalination technologies for seawater and brackish water have been adopted, becoming critically important. Reverse osmosis is the highest-rated technology for this process and generates two output streams: permeate water and brine, the latter characterized by a high concentration of total dissolved solids (TDS). When untreated, brine is discharged into water bodies and soils, causing ecological damage. To mitigate this impact, the circular economy proposes reusing part of the brine in agriculture through halophyte plants, which offer the advantage of growing under high salt concentrations. The objective of the research was to document the salinity tolerance of halophyte species and the potential use of water rejected from the desalination process as irrigation water, with a circular economy approach. Brine reuse represents an opportunity to reduce waste and generate environmental, social, and economic benefits. Among the main halophyte species capable of tolerating brine above 30 000 mg L^-1 are Suaeda salsa (L.) Pall., Salicornia bigelovii Torr., Rhizophora mangle L., and Chenopodium quinoa Willd. Salicornia europaea L. is classified as a halophyte species with medium tolerance (10 000–30 000 mg L^-1). Species with low salinity tolerance (5000–10 000 mg L^-1 TDS) include Atriplex nummularia Lindl., Zoysia japonica Steud., and Crithmum maritimum L. These plants also possess significant nutritional and pharmaceutical properties and can be used as livestock feed, human food, for oil extraction, soil remediation, and other applications.