Salinity reduction by Sarcocornia neei in hydroponics: implications in marine aquaculture wastewater remediation

Salinization has become one of the main environmental problems affecting the worldwide ecological balance. The effluent discharge of saline industrial effluents, such as marine aquaculture, and its rapid increase in global production in the last decades has become an important part of this problem. The halophyte Sarcocornia neei (Lag.) has proven its ability to remove and assimilate nutrients from saline wastewater, making it a promising candidate for application in phytoremediation systems. In this study, its ability to reduce water salinity was evaluated. For this purpose, the plants were reared for 53 days in artificial effluents at four different salinities: A) 0, B) 10, C) 20, and D) 30 g L^-1. A significant salt reduction was obtained in all treatments with NaCl addition. The maximum decrease was achieved in treatment C, reducing 6.91 ± 1.52 g L^-1, approximately 35% of the total added at the beginning of the trials. Plants tolerated all salt content ranges; no mortality or salt stress symptoms were observed in any treatment. The results obtained are a first approach suggesting that S. neei could be used for bio-desalination of saline wastewater. Further studies are needed to evaluate its application in pilot systems integrated into saline industrial effluents.