Geobiochemical Characteristics of Snow Cover on the White Sea Coast in 2021 and 2022

Abstract

For two years (2021 and 2022), snow sampling was carried out in the coastal zone of the Onega and Dvina Bays of the White Sea in the period of maximum snow accumulation (March). The snow was analyzed for the content of the major ions (Cl^–, \({\text{SO}}_{4}^{{2 - }}\), Na⁺, Ca²⁺, K⁺); nutrients (phosphorus, silicon, nitrogen), pH, and TDS. The algological composition of the snow cover was also studied. The results showed that the snow was slightly acidic (average pH 5.4). Cl^– and Na⁺ were the main ions in the coastal zone and \({\text{SO}}_{4}^{{2 - }}\) and Ca²⁺, in the estuary zone. A high content of marine ions and mineralization were determined near the Paranikha Bay (Dvina Bay), where releases of sea water onto the ice occur annually. Compared to previous studies, in which snow samples were taken in the coastal zone, the concentration of marine ions in the territory under consideration is an order of magnitude higher. The effect of marine aerosols results in that the values of snow cover mineralization can reach 140–680 mg/L. The concentration of dissolved silicon in melt water is higher in the zone influenced by atmospheric emissions from urbanized territories (Arkhangelsk, Novodvinsk, Severodvinsk), as well as near the granite quarry on the coast of Onega Bay. During the study period, 14 taxa of microalgae (species and supraspecific taxa), belonging to the division Bacillariophyta, were found in snow samples. The maximum value of the total number of microalgae (1.293 thousand cells/L) in the snow cover was determined in 2022.