The temporal and spatial analysis of transport impact on trace elements in snow samples

More than half of the world population lives in cities. In 2030, 80% of the world population will live in urban areas, according to United Nations migration forecasts. People who are living in cities are exposed to air pollution. The concentration of air pollution is increased by traffic intensity. Increasing traffic intensity increases the number of automobile congestion in large cities. Therefore, there is a need to implement the measures for reducing air pollution in surroundings. Scientific studies show that emissions from vehicle establish more than 90% of air pollution in the urban environment. Air pollution is associated with many premature deaths every year. The snow samples from the entire depth of snow show the pollution rate during the period of the permanent snow blanket and the sampling time. In this study, snow blanket pollution was investigated in Jelgava in February 2017 and 2018 after exposition of 7 days. The 20 sampling plots were created in the city and one plot in the natural area of the southern side of Jelgava. In each sampling area, 1.0-1.5 kg of snow was collected and in each plot 3 samples were taken for testing. In 2017, the average snow depth was 6-10 cm, but in 2018 the snow depth was 7-12 cm. The chemical elements were detected in 63 snow samples from February 2017 and 63 in snow samples from February 2018. 126 snow samples in total were analysed. The concentrations of the chemical elements were calculated in the melting snow water and in the HNO3 solution. Concentrations were determined by using an inductively connected plasma atomic emission spectroscopy (ICP-AES) method. The results of the chemical elements in snow show a similar level of pollution. However, there are minor differences in the spatial distribution of pollution due to differences in transport flow and climate conditions.