Evaluating the Rate of Atmospheric Dust Deposition in Isfahan Province

Abstract

The present study investigates seasonal and spatial variations in atmospheric dust deposition rate (DDR) and the concentration of dust-borne heavy metals in the eastern part of Isfahan as well as Segzi plain located in the central part of Iran. Dust samples were collected from nine different sites on a monthly basis from December 2016 to September 2017. The total concentrations of Pb and Zn were measured. The lowest value of DDR was observed in the winter due to low amount of precipitation, and the highest value was recorded in the summer. Seasonal distribution of the concentration of dust-borne heavy metals revealed that almost all the metals follow the pattern: fall ˃ spring ˃ summer. Spatial distribution of dust-borne Pb and Zn followed almost the same trend and the highest concentrations were observed in the western parts of the study area. It seems that fossil fuel, vehicle traffic, and industrial activities are the most important anthropogenic factors contributing to dust-borne heavy metals in the study area.

Investigation of Dust Deposition in Vegetation Period as an Ecological Service on Urban Trees in Budapest—A Case Study

“…For example, 'Woodii' gave high amounts of deposited dust in every investigated time, which may have been because its area is windy and located next to the Danube, which is surrounded by heavy traffic. This environmental exposure can significantly influence the dust deposit of those trees [16,21,30].…”

“…Precipitation can wash the dust off the leaves to a greater or lesser extent. Wind speed and direction can affect the amount of dust deposited [14][15][16][17][18].…”

“…The current value is influenced by many factors. The velocity and direction of air-borne pollutants spreading depend on many factors, such as surface roughness, vegetation, soil or topographic properties, urban condition, building size, the direction and width of roads, the wind speed, etc., which affect different dust deposition rates [16]. Previous experiments prove that the value of air pollutants in cities is higher than in rural areas and seasonal variation is less important than geographic location [17].…”

“…In addition, PM 10 , or smaller particles, mostly contain sulfate, ammonium, nitrate, elemental carbon, condensed organic compounds, minerals, microorganisms, and heavy metals [14,15]. The smaller the particulate size, the higher their adsorption capacity, and therefore, the higher their pollution potential [15,16].…”

“…However, this period is heavily burdened by air pollutants from heating [7]. Some research papers [15][16][17] claim that seasonal variation is not significant in relation to dust deposition, while others prove that seasonality is stronger [17][18][19][20][21].…”