PM10 Emissions Reduction from Exposed Areas Using Grass-Planted Covering: Field Study of a Construction Site

Vegetation or grass-planted covering has been demonstrated to be a cheap and effective method to prevent fugitive particular matter, which is a typical air pollution source emitted from exposed areas like farmlands or construction sites. A series of systematic experiments were carried out to continuously measure the dynamic variability of particulate matter sized less than 10 μm (PM10), and thus the reduction efficiencies of PM10 calculated using the experimental data. The reduction efficiency was found significantly affected by the grass covering height, and maximum reduction efficiency was concluded to be not more than 45%. Correlated with grass height, a useful correlation is proposed to estimate the reduction efficiencies that would be valid under the appropriate conditions suggested by this work. Using this correlation, the reduction efficiencies of PM10 can be predicted and provide a practical guideline for environmental management or engineering applications. It must be emphasized that the reduction efficiency approaches zero as the grass height is less than about 2 cm. This implies that PM10 reduction is inefficient if the grass is not high enough over the exposed area. Another point of interest is that total elimination of PM10 emission is not possible even when the grass is high enough with full coverage over the exposed area. Some constraints to applying the results obtained from this work are also discussed.