Separation of the anthropogenic portion of heavy metal contents along a highway by means of magnetic susceptibility and fuzzy c-means cluster analysis

摘要

pollution caused by traffic represents one of the most important environmental stress. In addition to gaseous components solid particulates from combustion and abrasion are emitted and increase the concentrations of certain heavy metals and magnetic constituents in roadside soils. These magnetic particles were identified under optical microscope. Some heavy metals show a positive correlation to magnetic susceptibility (χ). Contrary to the analysis of heavy metals, magnetic susceptibility can be measured fast and cost-effective. However, in the soil different sources of heavy metals with different magnetic properties are superposed. The anthropogenic input in the soil was discriminated from pedogenic/geogenic zones by means of principal component analysis and fuzzy c-means cluster analysis. The samples which belong to the most polluted part show more significant positive correlations between χ and certain heavy metals. With the help of suitable statistical analysis χ measurements support to identify those parts in soils which were polluted by traffic.