Assessment of Metal Pollution of Roadside Landscapes in the North of Western Siberia Using Statistical Modeling

The article presents an assessment of roadside soil and plant pollution by motor vehicles in the Arctic zone of Western Siberia. The studies were conducted on the Surgut-Salekhard highway near Novy Urengoy and on one of the winter roads south of the town of Tazovsky. A detailed geochemical characteristic of the parent rocks and soils in the study areas is provided. Chemical pollution was mild, since northern roads usually have low to medium traffic intensity. Statistical modeling based on the consistent application of factor and discriminant analyses of multivariate statistics was used to detect and identify pollutants and the pollution level. It has been shown that the Cd–Pb–Zn–Cu–Ni association in soils indicates the motor vehicles pollution. An additional source of impact in the urban area was residential construction through the Ca–Mn–Co–Sr–Zn association. Similar parageneses have been identified in the study of the solid phase of snow collected at the soil sampling sites, indicating the decisive role of aerotechnogenic transfer of metals in pollution of natural and urban environments. Low activity of lateral and radial migration of metals has been shown even in an acidic medium, attributed to the widespread peat horizon that functions as a compound geochemical barrier: alkaline, biogeochemical, and sorptive. A change in the chemical composition of indicator plant species has been established, caused largely by aerotechnogenic transfer of metals coming from motor transport and road surfaces. Soil pollution within the former winter road and in roadside landscapes has been found to be local. However, there were traces of disturbed soil cover, and soil thawing and an increase in the seasonally thawed layer thickness have been established. In general, chemical pollution caused by the impact of motor transport was not pronounced, and the content of the studied metals was below the standards established for soils (MPC and TPC). Calculation of the toxicity probability index (MERMQ) for contaminated soils showed low to moderate risk levels.