Hydrochemical characteristics of snow and lake waters of Antarctic oases in the areas of research stations

The results of analysis of major, minor and trace elements in snow and lake waters collected in January - May 2023 within the areas of location of Russian and Belarusian research stations are presented. The samples of snow and surface waters on King George Island (Waterloo), Schirmacher, Molodezhny and Vecherny oases, Larsemann Hills, as well as the Banks of Pravda and Ingrid Christensen were collected. The concentrations of 25 macro- and microelements were determined using the ICP-MS method, and the main ions were determined by titro- and turbidimetric methods. The maximum concentration of sodium (14.95 mg/l) was detected in the snow cover near the Mirny station; here, its average concentration is the highest as compared to other stations (4.65 mg/l). The lowest sodium concentrations (0.30-0.41 mg/l) are characteristic of the snow cover in the Molodezhny Oasis. Among the minor and trace elements iron is dominated at the majority of stations. It is shown that the investigated lakes of the Larsemann Hills (Low, Reid and Stepped) are sodium chloride in composition, the Lake Kitezh on King George Island (Waterloo) is sulfate-chloride calcium-magnesium, the lakes in the Vecherny Oasis are hydrocarbonate-chloride sodium, and Lagernoye Lake in the Molodezhny Oasis - chloride-hydrocarbonate magnesium-calcium. The revealed differences in the hydrochemical composition of snow and surface waters are conditioned by the distance from the coastline and protection from sea aerosols, as well as due to anthropogenic impact. The studies have shown that the snow and lakes of the coastal zones of the Larsemann Hills and the Pravda Coast in the vicinity of Mirny station are subject to the greatest impact of marine aerosols, and the least impact is the zone of the Schirmacher Oasis, most distant from the coast, near the Novolazarevskaya station. The importance of developing the research within the limits of one hydrological year aimed at estimating the inter-annual variability of hydrochemical parameters and revealing trends of changes with regard for various impact factors is shown.