Wetland Ramsar site in Tunisia (Soliman brackish lagoon) : status, threats, and protection

The Ramsar wetlands are crucial for global ecology. They are essential for preserving the balances of ecosystems. The aim of this work is to prevent the current situation of Sebkha of Soliman (880 ha; 36°43'N, 010°29'E; Nabeul, Tunisia) from deteriorating further. It is one of the few wetlands that receives water from both the sea, Wadi, and a wastewater treatment plant. According to a study of the organic pollution in the Sebkha's waters and sediments conducted in March 2022, there are high concentrations of suspended matter, that exceed 80 mg/L. The total organic matter exceeds 110 g/kg DW, and the biological oxygen demand exceeds 56 mg O2/L. Additionally, there are more than 24*103 bacteria per liter., We also identified mineral pollution primarily caused by nitrate (2.4 g/kg DW), phosphorus (2.42 g/kg DW), and iron (40 mg/L). Pollution is dispersed over three areas: the least polluted area is near the sea, the most polluted area is in the center of Sebkha, and the area farthest from the sea has medium pollution levels. The distribution of pollutants in the Sebkha is influenced by the contribution of pollutants and the self-purification by seawater.