چکیده:
Dust storm is one of the criteria for air pollution, and pollution by Heavy Metal(HM) is one of the major environmental problems in the world. The objective of the present study was to assess some of HMs concentrations in the leaves and bark of cypress and atmospheric falling dust along the Yazd highway, Yazd Province, Iran. The total concentrations of cadmium (Cd), cobalt (Co), copper (Cu), nickle (Ni), lead (Pb), zinc (Zn), iron (Fe) and manganese (Mn) in the dust and plant samples were measured using atomic absorption spectrophotometry after digestion with acid. The results showed that the concentration of Zn and Cd metals in falling dust were the highest to the lowest, respectively. The distance from the highway significantly influenced the concentration of HMs in leaves and bark of the cypress tree. Moreover, the effect of HMs on the bark of this tree was higher than that of leaves, except for Cd, Co, Cu and Mn. Concentrations of Zn, Co, Ni and Fe increased with the increase in the distance from the highway due to multi-directional winds and the presence of other contaminants. The Pearson correlation analysis between the HMs found in the falling dust and Thuja orientalis L. showed that the input and controlling factors of these metals in the cypress tree were probably the same as the dust. The results further showed that the Thuja orientalis L. leaves with a metal accumulation index of 1973.16 mg/kg were more able to simultaneously absorb different metals. Therefore, since this green belt surrounds the Yazd urban area, it is expected that a significant amount of HMs will be absorbed by these trees.
خلاصه ماشینی:
A. Hakimzadeh Ardakani College of Natural Resources & Desert Studies, Yazd University, Yazd, Iran Received: 27 October 2018; Received in revised form: 29 May 2019; Accepted: 6 March 2020 Abstract Dust storm is one of the criteria for air pollution, and pollution by Heavy Metal (HM) is one of the major environmental problems in the world.
The objective of the present study was to assess some of HMs concentrations in the leaves and bark of cypress and atmospheric falling dust along the Yazd highway, Yazd Province, Iran.
Dust storms are among the natural disasters taking place in warm and humid regions such as Yazd province (Esfandiari, 2018); typically, desert dust contains large quantities of toxic substances that pose a hazard to the health of living organisms and ecosystems; due to the high emissions of dust debris inside the environment doses, HMs may be released on a large scale by binding to these particles; HMs are important due to their physiological effects on humans and other residing organisms at significantly low concentrations (Wan et al.
For this purpose, we determined the concentration of some HMs in the leaves and bark of the cypress tree and compared them with heavy metal concentrations in the falling dust.
76 )VIew the image of this page) The results of the analysis of variance (mean square) showed that distance from the highway had a significant effect on the concentration of some HMs in the leaf and bark of Thuja orientalis (P≤ 0.