This paper reports the results of an extensive investigation of water chemistry in the small lakes of European Russia and Western Siberia along a climatic gradient. It was demonstrated that small...

The distribution of trace elements of anthropogenic origin, especially toxic metals, is an environmental problem. We present the first results of research into the geochemistry of lake waters and metallic pollution in European Russia (ER) and Western Siberia (WS), based on a survey of 367 lakes from the tundra to the steppe zones. The content of more than 80 elements in the lake water was studied; the influence of airborne contamination and the geochemistry of water were estimated. We found that the concentrations of alkaline and alkaline-earth elements, as well as As, V, Co, U, Nb, Sb, increase with a change in the climatic gradient. This fact is explained not only by airborne contamination, but also by the geochemistry of lakes and the climatic factor (increased evaporation concentration). Anthropogenic eutrophication leads to an increase in the content of Fe, Sr, Mo, and acidification—Zn, Cd, Ni, Cu, and especially Pb. There are industry-specific influences: the waters of the northern regions of ER are enriched by Ni, Cd, As, Sb and especially Se because of the emissions from copper-nickel smelters. The oil and gas industry (WS) leads to increased concentrations of V, Pb and Mo in water. We assess the metallic pollution status of surface water in the Eurasian region of Russia using an enrichment factor (EF). In surface waters of ER and WS, metal concentrations do not exceed the maximum permissible concentration, but we have established higher concentrations of many elements in the background, including toxic ones. Prolonged low doses of toxic elements can be a potential hazard to ecosystems and humans. The results showed that from the northern to the southern regions the EF increases for most of the analyzed elements. It can be assumed that with climate warming the concentration of metals in these bodies of water will increase and this is dangerous for the environment.

The results of experimental studies of the composition and specific features of humic substance isolated from typical soils of natural zones are given. The stability constants of metal complexes with...

Acidic deposition has caused severe surface water acidification in Europe and the North America, but surface water acidification has not been systematically studied in Russia. Here we present the first detailed study on regional surface water acidification in European Russia and Western Siberia based on a survey of 367 lakes in a transect from the tundra to the steppe, which were investigated to explore the status and mechanism of surface water acidification. The variability of water chemistry is documented and discussed. High pH and acid neutralizing capacity (ANC) were observed for lakes in the southern region, indicating that surface water acidification does not occur here. Anthropogenic acidification occurs in the humid areas of both regions being observed in 4.4% of European Russia and 8.2% of Western Siberia lakes. These tundra and taiga lakes are characterized by high transparency, low pH and ANC with a high concentration of strong acid anions. The main factor leading to acidification in the European Russian lakes is sulfur emission from metal smelters whilst in Western Siberia acidification is associated with gas burning by oil production facilities. In the European Russian acid lakes, SO42- is dominant, in contrast to Western Siberia, where NO3- and Cl- are dominate. Influence of strong technogenic acids on structure of organic components and their possibility to form a proton is discussed. Phenomenon of incise of water acidification by organic acids and strong acids is explained. These results clearly show the effect of a number of factors which strengthen the acidity of water. Differences in the chemical composition of lakes of both regions, as well as differentiation by their acid properties, were statistically proved. Results of our research indicate the need to reduce emissions of acidic gases into the atmosphere.

The data on the metal contents and acidification of small lakes caused by airborne contamination of the watershed in three industrial regions of the Arctic—European Russia (Kola region), Western (Yamal-Nenets region) and Eastern Siberia (Norilsk region)—have been presented for the first time. It has been proven that acidification and enrichment by metals of water connect with sulfur dioxide and metals emissions from copper–nickel smelters, contaminating the catchments, with associated gas burning during raw hydrocarbon production. To assess the effects of acid deposition, critical loads and their exceeds were calculated: exceeded by 56% and 12.5%, respectively, in lakes in the Kola region and in the north of Western Siberia; the catchments of the East Siberian region are resistant to acidification. Water enrichment factors (EF) by elements were calculated to show that the waters of the Norilsk and Kola regions are enriched with Ni, Cd, As, Sb and Se as a result of emissions from copper–nickel smelters. The oil and gas industry in the northern regions of Western Siberia lead to the increase in V, Pb and Mo concentrations in the waters. The high values of EF and excess of acidity critical loads for water are explained by the local and transboundary pollution impacts on the catchment of small lakes.