The concentration of a Number of Heavy Metals in Dust in Ilam, Iran and Their Impact on Quercus brantii Lindl in the Region

This study was designed to evaluate the presence of some heavy metals in dust as well as their effects on soil, leaves and twigs of Brant s oak (Quercus brantii Lindl.) at a study site located in Meleh-Siah, Ilam province. Four elements including Pb, Zn, Ni and Cd were assessed in two different time spans (April and September 2013), corresponding to the dust occurrence for two groups of healthy and declining trees. The results showed that the amount of all elements except Zn was significantly increased in the sub-canopy soil for both groups of trees. All four elements absorbed by leaves of both healthy and declining trees were increased during early spring to late summer and their difference was significant in 95% confidence level. The amount of Pb, Ni and Cd grew in branches of healthy trees while there was no significant increase in branches of declining trees. There existed no significant difference between healthy and declining trees considering the studied elements except the amount of Zn in leaves at the second round of sampling. This study revealed that dust storms included heavy metals that were absorbed by leaves and roots of Quercus brantii Lindl. This seems to play a role in the decline of Quercus brantii Lindl resistance against other stress factors such as drought, pest infestation, climate change and livestock grazing.

کلیدواژه ها:

Quercus brantii Lindl decline ، Zn ، Pb ، Cd ، Ni ، dust