Application of magnetic susceptibility measurement for mapping and assessment of ecological quality in urban topsoils

Abstract

The article presents the results of geostatistical mapping of the magnetic susceptibility of the urban top soil. Soil magnetometry is well suited for rapid monitoring of pollution in urban areas due to its high sensitivity, ease of measurement, rapidity, high reproducibility of analysis, and low cost. This method allows obtaining large datasets with high resolution. The purpose of the study: spatial modeling of magnetic susceptibility and ecological-geochemical assessment of the top soil of Kudymkar city. The research area covers a section of the city with a total area of 32 km². Spatial modeling was carried out by the geostatistical method based on 51 soil samples. The background magnetic susceptibility of the soils of the city is 3–4 times higher than the magnetic susceptibility of the soils of the non-contaminated regional background. Soils with high and very high magnetic susceptibility occupy more than 30 % of the city area. Anomalous zones of soil magnetic pollution or magnetic “hot spots” formed near industrial facilities, heating boilers, on roadside soils with heavy traffic. A scale for the volumetric magnetic susceptibility of soils was developed on the centile analysis of the data. Strongly magnetic soils contain elevated concentrations of Zn, Cu, and Ni. The concentrations and names of pollutant metals in urban soils depend on the techno-geochemical specialization of cities. It can be recommended that the Environmental Services of cities use measurements of the magnetic susceptibility to monitor the ecological and geochemical state of soils and identify areas of city soils contaminated with heavy metals.