Snowpack is a unique indicator in assessing both local and transboundary contaminants. We considered the features of the snow chemical composition of the Valday Upland, Russia, as a location without a direct influence of smelters (conditional background) in 2016–2019. We identified the influence of a number of geochemical (landscape), biological (trees of the forest zone, vegetation), and anthropogenic factors (technogenic elements—lead, nickel) on the formation of snow composition. We found increases in the content of metals of technogenic origin in city snowfall in the snowpack: cadmium, lead, and nickel in comparison with snowfall in the forest. Methods of sequential and parallel membrane filtration (in situ) were used along with ion-exchange separation to determine metal speciation (labile, unlabile, inorganic speciation with low molecular weight, connection with organic ligands) and explain their migration ability. We found that forest snow samples contain metal compounds (Cu, Pb, and Ni) with different molecular weights due to the different contributions of organic substances. According to the results of filtration, the predominant speciation of metals in the urban snow samples is suspension emission (especially more 8 mkm). The buffer abilities of snowfall in the forest (in various landscapes) and in the city of Valday were assessed. Based on statistical analysis, a significant difference in the chemical composition of snow in the forest and in the city, as well as taking into account the landscape, was shown. Snow on an open landscape on a hill is most susceptible to airborne pollution (sulfates, copper, nickel), city snow is most affected by local pollutants (turbidity, lead).

The paper reports chemical data on the atmospheric precipitation within the studied area of the Valdai National Park during monitoring in 2015–2018. The main parameters of atmospheric precipitation as well as major and trace-element compositions of waters are analyzed. Seasonal dynamics and possible pathways of element uptake in atmospheric precipitation are considered. Multidimensional statistical analysis (PCCA, RDA analyses) was applied to determine geochemical and anthropogenic factors responsible for the formation of the chemical composition of atmospheric precipitation. Precipitations penetration through tree crown are enriched in organic matter and some elements. The high contents of N, Fe, Mn, Zn, and Cu found in subcrown waters indicate a predominant biogenic migration of the elements with atmospheric fallouts. The elevated contents of Cu and Zn, as well as Cd and Pb in the atmospheric fallouts of the Valdai National Park suggest that the studied area experiences a regional-scale anthropogenic load.

The paper presents data on the features of Hg distribution and its input in dated bottom sediments in two Arctic lakes: Longtibeito on the Yamal Peninsula and Gol’tsovoe on the Gydan Peninsula. The Hg concentrations are much higher in the upper layers of the sediments, and the enrichment factors are 14 and 10 at background concentrations of 4.3 and 5.2 ng g^–1, respectively. The sedimentation rates in both lakes are fairly high: the rate for Longtibeito Lake varied relatively little and is 660 ± 75 g m^–2 year^–1 on average, and that for Gol’tsovoe Lake decreased toward upper layers from 791 to 513 g m^–2 year^–1. The fluxes of total Hg in these lakes are principally different, but their lithogenic fluxes are approximately equal: 5–7 μg m^–2 year^–1. Mercury flux into Longtibeito Lake is much higher than into Gol’tsovoe Lake and amounts to 41.5 μg m^–2 year^–1. Layer-by-layer grain-size analysis with determination of Hg in each fraction, highlights differences between the lakes. The total Hg concentration in a layer in Gol’tsovoe Lake is controlled by the fine fraction (0.2 mm) particles with high Hg concentrations. One of the likely reasons for the increase in Hg concentration in the upper layers may have been the development of oil and gas fields in this territory.