Research on the Physical and Chemical Properties of Water in Boyukshor and Khojasen Lakes

The article is a comparative evaluation of the physicochemical and microbiological parameters of the water in Lake Boyukshor and Khojasan, which are ecologically sensitive water bodies on the Absheron Peninsula. As emphasized in the article’s introduction, the lakes have been impacted by the production of oil, industrial wastes, domestic wastewater, and urbanization for a number of years due to the closed hydrological regime and low self-purification ability; as a result, the accumulation of substances has increased. The analysis results show that the pH in both lakes is weakly alkaline (Boyukshor 8.44; Khojasan 8.22), and the temperature is typical for the summer season. Color, turbidity, and salinity indicators are higher in Lake Boyukshor; TDS (35,200 mg/L), electrical conductivity (58,900 µS/cm), and chloride (24,959 mg/L) confirm its hypersaline nature. A dissolved oxygen level of 1.92 mg O₂/L indicates that the oxygen deficit has reached a critical level. In Lake Khojasan, the OCT of 177 mg O₂/L indicates a higher content of oxidizable organic matter, and the high level of enterococci in microbiological indicators indicates that sanitary risks remain strong. The proposed measures include pollution source control, aeration, biogen limitation, it is based on selective sediment treatment and strengthening of systematic monitoring. Overall, the results show that ecological risks are still high in both lakes. However, it shows that the main problems in the lakes are dominated by different directions (hypersalinity and oxygen deficiency in Boyukshor, organic load and microbiological risk in Khojasen).