Marmara Lake (Manisa-Türkiye)'s Final Waters: Assessment of Water Quality Parameters and Trophic Status Before Near-Total Drying

This study was carried out at 3 different stations in Marmara Lake, in Western Anatolia in Türkiye, and focused on variations in water quality parameters based on months. Water samples collected from the surface of the lake were analyzed monthly in terms of total suspended solids (TSS), volatile suspended solids (VSS), fixed suspended solids (FSS), ammonium nitrogen (NH4+-N), nitrite nitrogen (NO2--N), nitrate nitrogen (NO3--N), phosphate phosphorus (PO4-3-P), silica (SiO2) and chlorophyll-a (Chl-a) parameters. As a result of this study, according to Inland Water Quality Standards defined in Surface Water Quality Management Regulations (SWQMR), Marmara Lake can be considered the Class-I quality by the measured ammonium nitrogen and nitrate nitrogen and the Class-II by the measured nitrite nitrogen and phosphate phosphorus. Moreover, it was evaluated that the lake is in a eutrophic status according to its Carlson’s trophic state index (TSI) scores based on the phosphate phosphorus values, and in a hypereutrophic status based on the chlorophyll-a values. This study presented the latest scientific research evaluating the surface water quality parameters and trophic levels of Marmara Lake before its complete drying. In this respect, the study has historical importance in documenting the lake's final ecological state and will be able to create a critical reference point for potential restoration efforts.