Mapping of heavy metal loadings in soils by means of magnetic susceptibility measurements

Contamination of soils with heavy metals is an issue all industrial and urban regions have to deal with. Generally, chemical methods are chosen to monitor soil pollution but measurements of magnetic susceptibility proved to yield additional information at low cost and consuming less time. We measured the magnetic susceptibility of soils which had been analysed chemically during the soil surveys of three Austrian provinces. Each anomaly of susceptibility either coincided with geogenic anomalies or indicated anthropogenic input of pollutants. Regional comparisons of susceptibility with chemical analyses revealed that susceptibility can be used as an indicator for the contents of individual pollutants in soils. This calibration of susceptibility has been successfully applied to an industrial region as well as to an urban environment. Two powerful applications of susceptibility measurements of soils are shown: the identification of polluted areas, and the detailed mapping of these areas to reveal the extent of pollution.