Assessment of snow cover pollution in urban ecosystems of the Kola North in the zone of influence of railway branches
N.V. Saltan, Е.А. Sviatkovskaya, N.N. Trostenyuk
Section: Monitoring of natural and anthropogenically disturbed areas
The chemical composition (pH, the content of the principal cations and anions, Ni, Cu, Pb, Fe) of snow cover on the territory of railway stations in the cities of the Murmansk region (Murmansk, Olenegorsk, Apatity, Polyarnye Zori, Kandalaksha) and in the background area was first studied. The snow sampling was carried out from late March to early April 2019 at a distance of 3–6 m from the railway track. It has been revealed that the acidity of urban melt water corresponded to weakly acidic and neutral values. Compared to the melt water of background territories, the concentrations of ions such as Na+, Са2+, НСО3-, Cl- significantly were increased, especially in Murmansk and Olenegorsk. Two forms of the presence of heavy metal (dissolved and solid) in the snow were analyzed. It has been established that metals during the winter period were received to the atmosphere mainly in solid form, which indicates the technogenic origin of their sources of supply. The highest proportion of solid phase is typical for Fe (>98%). Ecological and geochemical indicators (values of the concentration coefficients, the total contamination index - Zc) of snow pollution were considered. It has been found that the total concentrations of elements of hazard classes 1(Pb) and 2 (Ni, Cu) are 3–28 times higher than background values. According to the total contamination index, railway station territories of the cities Polyarnye Zori (Zc=19), Apatity (Zc=25), Kandalaksha (Zc=28) were characterized by a low level of pollution, Murmansk (Zc=77) – medium, Olenegorsk (Zc=183) – high (due to the functioning of the iron ore concentrate production plant). It has been shown that railway transport contributes to the entry into the atmosphere of solved forms of heavy metals, mainly Fe.
Keywords: snow cover pollution, urban ecosystem, railway transport, Kola North.