Physico-chemical features of the water in the Atlasovskie lakes of Yakutsk

The city of Yakutsk contains a network of interconnected lakes known as the Yakutsk City Canal. The ecological status of the water bodies within it deteriorated due to disruptions in its flow and water supply in the late 20th century, primarily from the Shestakovka River. In recent years, the connection between the city's lakes and the river has been restored. The first group of water bodies receiving water from the Shestakovka River, and the subject of this study, are the Atlasovskie Lakes. This study established that two of the five lakes surveyed are isolated and do not communicate with other water bodies. The water in these lakes is fresh, soft, neutral, and slightly alkaline. Lakes AT3, AT4, and AT5 exchange water masses and receive river water, as evidenced by the similar chemical composition of their waters: reduced mineralization, general hardness, elevated phosphate concentrations, and proportions of hydrocarbonates and calcium. The water in this group is predominantly ultra-fresh, very soft, and neutral. Compared to the largest bodies of water in Yakutsk (Saisar, Sergelyakh, Khatyng-Yuryakh, Ytyk-Kyuel, and Beloye), the Atlasovskie Lakes have lower pH values, lower sodium ion content (40% lower on average) and sulfate content (23% lower on average), and a higher magnesium content (12% lower on average). Elevated total iron concentrations were observed in all studied lakes, which may be related to high background concentrations of this component in the environment and is typical of water bodies in Central Yakutia.