Response of magnetic properties to metal deposition on urban green in Nanjing, China
Autor: | Jinhua Wang, Huiming Li, Cheng Wang, Xin Qian, Leng Xiangzi, Yixuan Sun |
---|---|
Rok vydání: | 2017 |
Předmět: |
Pollution
China 010504 meteorology & atmospheric sciences Environmental magnetism Health Toxicology and Mutagenesis media_common.quotation_subject Air pollution 010501 environmental sciences medicine.disease_cause 01 natural sciences Trees Magnetics Metals Heavy Biomonitoring medicine Environmental Chemistry Industry 0105 earth and related environmental sciences media_common Pollutant Spectrometry X-Ray Emission Dust General Medicine Evergreen Particulates Plant Leaves Deposition (aerosol physics) Environmental chemistry Environmental science Particulate Matter Environmental Pollution Environmental Monitoring |
Zdroj: | Environmental science and pollution research international. 24(32) |
ISSN: | 1614-7499 |
Popis: | Environmental magnetism is a simple and fast method that can be used to assess heavy metal pollution in urban areas from the relationships between magnetic properties and heavy metal concentrations. Leaves of Osmanthus fragrans, one of the most widely distributed evergreen trees in Nanjing, China, were collected from four different district types, i.e., residential, educational, traffic, and industrial. The magnetic properties and heavy metal concentrations were measured both for unwashed (dust-loaded) and washed leaves. Scanning electron microscopy with energy-dispersive X-ray spectroscopy confirmed that unwashed leaves accumulated much dust due to atmospheric deposition. The value of magnetic properties and heavy metal concentrations in unwashed leaves was significantly higher than those of washed leaves, indicating that these characteristics were mainly derived from atmospheric particulate matter. Saturation isothermal remanent magnetization (SIRM) values obtained from unwashed and washed leaves ranged from 209.14 × 10−6 to 877.85 × 10−6 Am2 kg−1 and from 69.50 × 10−6 to 501.28 × 10−6 Am2 kg−1, respectively. High concentrations of heavy metals, such as Pb and Fe, the Tomlinson pollution load index, and the SIRM of unwashed leaves occurred in the traffic and industrial districts. A preliminary principal component analysis identified the source categories and suggested that industrial activities may be more related to the release of particulate matter rich in Fe. The heavy metal concentrations and pollution load index showed significant positive correlations with the low-frequency magnetic susceptibility and SIRM of unwashed leaves, indicating that these properties can be used to semi-quantify atmospheric heavy metal pollution. Our study suggests that it is possible to employ magnetic measurements as a useful tool for the monitoring and assessment of atmospheric heavy metal pollution. |
Databáze: | OpenAIRE |
Externí odkaz: |