Management of hazardous road derived respirable particulates using magnetic properties of tree leaves (original) (raw)
Related papers
Monitoring Of Vehicles Derived Particulates Using Magnetic Properties Of Leaves
Environmental Monitoring and Assessment, 2006
Biomonitoring of vehicle-derived particulates is conducted by taking magnetic measurements of roadside tree leaves. Remanent magnetization (IRM300 mT) of more than 400 Delbergia sissoo leaves was determined and IRM300 mT normalized for the leaf area. The normalized 2-D magnetization as shown by results is dominantly controlled by the tree's distance to the road. The spatial and temporal variations of vehicle-derived particulates were mapped using magnetic analysis. 2D-magnetizations values were higher for leaves collected adjacent to major road sections than for those from village road suggesting vehicle emissions, rather than resuspended road dust, as the major cause of magnetic particles of roadside tree leaves. Vehicles derived particulates are responsible for tree leaf magnetism, and the leaf magnetizations values fall significantly from high values proximal to the roadside to lower values at the distal side. This suggests the ability of trees to reduce particulates concentrations in the atmosphere. The rainfall produces a net decrease in the leaf magnetic dust loadings.
Atmospheric Environment, 1999
We report here the novel use of rapid and non-destructive magnetic measurements to investigate the spatial and temporal pattern of urban dust loadings on leaves of roadside trees. More than 600 leaves were collected from birch trees and their remanent magnetization (IRM 2) determined and normalized for the leaf area. The results show that this normalised 2-D magnetization is dominantly controlled by the tree's distance to the road. The magnetic analyses enabled detailed mapping of the spatial and temporal variations of vehicle-derived particulates. Higher 2D-magnetizations, indicating higher magnetic dust loadings, were measured for leaves collected adjacent to uphill road sections than for those next to downhill sections. This suggests that vehicle emissions, rather than friction wear or resuspended road dust, are the major source of the roadside magnetic particles. Additional magnetic analyses suggest that the particle size of the magnetic grains dominantly falls in the range classi"ed for airborne particulate matter as PM ((2.5 m), a particle size hazardous to health due to its capacity to be respired deeply into the lungs. Thus, the leaf magnetizations relate directly to release into the atmosphere of harmful vehicle combustion products. For leaves from individual trees, magnetization values fall signi"cantly from high values proximal to the roadside to lower values at the distal side, con"rming the ability of trees to reduce aerosol concentrations in the atmosphere. Magnetic analysis of leaves over days and weeks shows that rainfall produces a net decrease in the leaf magnetic loadings.
Chinese Science Bulletin, 2006
This is a report on magnetic properties of highroad-side tree (Pinus pumila Regel) leaves collected along an expressway linking Beijing City and the Capital International Airport and further focus on their environmental contributions. A series of rock magnetic experiments show that the primary magnetic mineral of leaf samples was identified to be magnetite, in the pseudo-single domain (PSD) grain size range 0.2–5.0 μm. On the other hand, magnetite concentration and grain size in leaves are ascertained to decrease with increasing of sampling distance to highroad asphalt surface, suggesting that high magnetic response to traffic pollution is localized within a distance of some two meters away from highroad asphalt surface. Although magnetic susceptibility is ordinarily regarded as a simple, rapid and low-cost method for monitoring traffic pollution, saturation isothermal remanent magnetization (SIRM) can be treated as a valid proxy for monitoring air particulate matter (PM) when samples are magnetically weak. It is believed that a synthetic rock magnetic study is an effective method for determining concentration and grain size of ferromagnets in the atmospheric PM, and then it should be a rapid and feasible technique for monitoring atmospheric pollution.
Biomonitoring of particulate matter by magnetic properties of Ulmus carpinifolia leaves
AFRICAN JOURNAL OF BIOTECHNOLOGY, 2012
Biomonitoring of the particulate matter (PM) helps us to find out quantity and quality of vegetation in different parts of the city and create sustainable urban landscape. This study explains the results of an air pollution biomonitoring in Isfahan (Iran) with regards to the magnetic properties of tree leaves of Elm (Ulmus carpinifolia). Isothermal remanent magnetization (IRM 300 mT) of U. carpinifolia leaves was determined. Data collection apparatus was a magnetometer. Four stations in different areas of green space, including, one park, one square, one street and one control station were determined and the tree leaves of U. carpinifolia from two meter height were collected. Ten leaves from each tree were separated and ten repetitions were achieved for each station. Leaves were placed in a special box to measure magnetic field with magnetometer. Comparison of magnetic properties of Elm tree leaves before and after washing was done. Magnetic properties showed that high concentrations were seen in trees found in squares and streets. Also, rainfall and washing decreased the magnetic properties of the leaves.
Atmospheric Environment, 2005
Dust-loaded tree leaves from Kathmandu have been analyzed for magnetic susceptibility (w) and heavy metal (HM) contents. For 221 samples of leaves of cypress (mainly Cupressus corneyana), silky oak (Grevillea robusta) and bottlebrush (Callistemon lanceolatus), w has a range of (0.01-54) Â 10 À8 m 3 kg À1 with a median of about 10.0 Â 10 À8 m 3 kg À1 . Trees situated close to the busy road intersections, near the main bus station and sectors of roads with steep slope yield elevated susceptibility.
Air pollution survey in Rome using magnetic properties of tree leaves
2003
We report a biomonitoring study of air pollution in Rome based on the magnetic properties of tree leaves. In a first step, magnetic properties of leaves from different tree species from the same location were compared. It was observed that leaves of evergreen species, like Quercus ilex, present much higher magnetic intensities than those of deciduous species, like Platanus sp., suggesting that leaves accumulate magnetic pollutants during their whole lifespan.
Present study was performed in urban forests of Aizawl, Mizoram, North East India falling under an Indo-Burma hot spot region of existing ecological relevance and pristine environment. Phyto-sociolology of invasive weeds has been performed and results revealed that Lantana camara was the most dominant invasive weed. Further, the air quality studies revealed high suspended particulate matter (SPM) as well as respirable suspended particulate matter (RSPM) in ambient air of Aizawl, Mizoram, North East India. Bio-magnetic monitoring through plant leaves has been recognised as recent thrust area in the field of particulate matter (PM) science. We aimed to investigate that whether magnetic properties of Lantana camara leaves may act as proxy of PM pollution and hence an attempt towards it's sustainable management. Magnetic susceptibility (χ), Anhyste reticremanent magnetization (ARM) and Saturation isothermal remanent magnetization (SIRM) of Lantana camara plant leaves were assessed and concomitantly correlated these magnetic properties with ambient PM in order to screen this invasive plant which may act as proxy for ambient PM concentrations. Results revealed high χ, ARM, SIRM of Lantana camara leaves and moreover, these parameters were having significant and positive correlation with ambient SPM as well as RSPM. Therefore, present study recommended the use of Lantana camara as bio-magnetic monitor which may further have sustainable management implications of an invasive plant.