Magnetic Susceptibility and Heavy Metals in Urban Soil (Khvalynsk, Saratov Region, Russian Federation)

Abstract

Magnetic susceptibility is a fast, inexpensive and reliable technique for estimating and monitoring the anthropogenic contamination of soil with heavy metals. However, it is essential to determine the factors affecting magnetic susceptibility before applying this technique to environmental studies. The objectives of this study were to investigate: the effect of parent materials and land use on the magnetic susceptibility and concentrations of Cd, Cr, Cu, Ni, Pb and Zn, and the capability of magnetic susceptibility to be an indicator of anthropogenic heavy metal contamination of soil in Khvalynsk, Saratov region, Russian Federation. 46 composite surface soil samples (0–10 cm) were taken. 1 M HNO3 extractable concentrations of Cd, Cr, Cu, Ni, Pb and Zn were determined by atomic absorption spectroscopy. Magnetic susceptibility at low and high frequency (χlf and χhf) was measured and frequency dependent susceptibility (χfd) was calculated. The average concentrations of Cd, Cr, Cu, Ni, Pb and Zn were 0.14; 0.43; 20.82; 4.14; 3.15 and 63.24 mg/kg, respectively. Magnetic susceptibility varied from 1.81 to 77.2 × 10−7 m3 kg−1. Correlations between magnetic properties and mobile forms of heavy metals in the soils of Khvalynsk have not been established. Therefore, in the soils studied, magnetic susceptibility could not be employed as an indicator of anthropogenic contamination of soil with heavy metals. Magnetic susceptibility can be used to assess the degree of soil transformation in Khvalynsk.