A Magnetic Study of a Polluted Soil Profile at the Shijingshan Industrial Area, Western Beijing, China

Abstract

A soil profile of 74 cm length was sampled in the hillside close to Beijing Muslim's cemetery, which is located in the Yingshan Forest Park near the Shijingshan industrial area. Coal-fired power plants, a steel mill, and a cement factory are located close to the sampling site. Gray-black pollutants can be found within the uppermost part of the soil. Magnetic measurements, grain size and geochemical analysis, as well as multivariate statistics were performed. Magnetic proxies show similar trends compared to heavy metal elements with higher concentrations at the top and lower concentrations in the lower part. The anthropogenic dust input from industrial activity is the predominant cause for strong magnetic signals in the uppermost soil horizon (0∼3 cm). The main magnetic component is magnetite contained in the grain size fractions of 4∼16µm and 16∼32µm. These pollutants are observed up to about 10 cm depth. Below 10 cm, there is little pollution in soil with lowest concentration of magnetic minerals and heavy metals comparable to natural background values. Multivariate statistics and fuzzy C-means cluster analysis show positive correlation of χ, ARM, SIRM and Mn, Cu, Fe, Pb, Zn, Al, Sr. Based on the results, it can be concluded that magnetic parameters can be used as a sensitive indicator for screening heavy metal pollution.

Spatial and temporal variation in magnetic properties of street dust in Lanzhou City, China

“…In contrast, the main traffic arteries and areas of dense residential use show high χ lf values. The spatial distribution of χ lf in Lanzhou street dust shows that residential use, industrial development and heavy traffic represent high magnetic susceptibility χ lf value distribution areas, consistent with previous studies [16,[20][21][22]38,39] . Furthermore, the high values of the magnetic difference between the heating periods and non-heating periods are centralize in the Xigu District and Chengguan District.…”

Magnetic properties of street dust and topsoil in Beijing and its environmental implications

“…They are mainly from vehicle emission [21] , industrial activity [22][23][24] , and dust storm [25,26] . In these studies, magnetic technique has been proved a highly useful tool in discriminating origination of urban dusts [1][2][3][4]9,12,[18][19][20] .…”

Mineral magnetic properties of surface sediments at Bei’anhe, Beijing, and its environmental significance

“…These parameters are the complex reflection of the mineralogy, concentration and grain size of magnetic minerals contained in the sediments. The section shows striking differences with typical polluted sections [14] at aspects of the concentration of magnetic minerals in the topsoils, the distinct distribution character and infiltration depth of contaminating materials along with depth. Magnetic susceptibility of polluted soils is usually higher than 400×10 −8 m 3 kg −1 [14,32] , and the frequency-dependent magnetic susceptibility is negatively correlative with magnetic susceptibility [32] .…”

“…The evident increase of magnetic mineral concentration on bush leaves less than 2 m apart from highway identified the traffic pollution and its main coverage [13] . The contamination of ARTICLES GEOMAGNETISM heavy metal particles including magnetic minerals transferred to soils by wind were heaviest in the upper 3 cm and can infiltrate to 10 cm in depth [14] . Pollution caused high susceptibility and the magnetic particles from pollution are usually coarser than those from natural processes [12][13][14] .…”

“…The contamination of ARTICLES GEOMAGNETISM heavy metal particles including magnetic minerals transferred to soils by wind were heaviest in the upper 3 cm and can infiltrate to 10 cm in depth [14] . Pollution caused high susceptibility and the magnetic particles from pollution are usually coarser than those from natural processes [12][13][14] . The former researches focus on urban and industrial areas in Beijing, while systematic mineral magnetic studies remain very scarce for latter-day and modern surface sediments and soil sections around Beijing.…”