Impact of grass cover on the magnetic susceptibility measurements for assessing metal contamination in urban topsoil

• Published in: Environmental research 2017-05, Vol.155, p.294-306
• Main Authors: Golden, Nessa, Zhang, Chaosheng, Potito, Aaron P., Gibson, Paul J., Bargary, Norma, Morrison, Liam
• Format: Article
• Language: English
• Subjects: Cities; Environmental magnetism; Environmental Monitoring; Grass cover; in situ MS; Ireland; Magnetic Phenomena; Magnetic susceptibility; Metals, Heavy - analysis; Poaceae; Soil metal contamination; Soil Pollutants - analysis
• ISSN: 0013-9351; 1096-0953
• DOI: 10.1016/j.envres.2017.02.032

In recent decades, magnetic susceptibility monitoring has developed as a useful technique in environmental pollution studies, particularly metal contamination of soil. This study provides the first ever examination of the effects of grass cover on magnetic susceptibility (MS) measurements of underlying urban soils. Magnetic measurements were taken in situ to determine the effects on κ (volume magnetic susceptibility) when the grass layer was present (κgrass) and after the grass layer was trimmed down to the root (κno grass). Height of grass was recorded in situ at each grid point. Soil samples (n=185) were collected and measurements of mass specific magnetic susceptibility (χ) were performed in the laboratory and frequency dependence (χfd%) calculated. Metal concentrations (Pb, Cu, Zn and Fe) in the soil samples were determined and a gradiometry survey carried out in situ on a section of the study area. Significant correlations were found between each of the MS measurements and the metal content of the soil at the p