Integrating Desert Sand Utilization in Saltwater Aqua-Vegeculture Production: Performance Evaluation of Yield and Biochemical Composition

Background: Saline aquaponics integrates fish and crop cultivation in saltwater environments by utilizing abundant saltwater resources. The integrated aqua vegeculture system (iAVs) shows promise for water conservation and environmental resilience. Objective: To evaluate lettuce growth in iAVs with varying salt levels and investigate how saltwater impacts the biochemical properties and growth of both fish and lettuce. Methods: Over four months, iAVs were incorporated into an existing aquaponic system with lettuce (Lactuca sativa) and tilapia (Oreochromis niloticus). Four treatments were tested: freshwater (control-T1) and saltwater concentrations of 1 (T2—2.5%), 2 (T3—5%), and 3 (T4—7.5%). Results: Increased salinity did not affect the fish growth parameters, with a 90% survival rate across all groups. Higher salinity levels potentially improve fish farming efficiency. Lettuce growth was optimal in freshwater, with promising results at the T2 and T3 levels, but T4 had negative effects. Proximate composition analysis showed a decline in lettuce nutritional elements as the saltwater concentration increased. Conclusion: This approach could transform food production in coastal regions and arid nations, addressing food security and water scarcity issues while alleviating the pressure on freshwater sources.