Assessment The Response of Urban Tree Species to Air Pollution Using Biophysical and Biochemical Leaf Biomarkers

Regarding to the role of trees in reduction and absorption air pollutants, assessing the tolerance of different tree species to environmental pollutants is very much important in order to select suitable species around any polluted place. Therefore, the aim of this study was to evaluate the tolerance of P. orientalis, M. nigra and A. altissima species to air pollution using biophysical and biochemical leaf biomarkers.

For this purpose, sampling of the leaves from all three species was carried out at six stations in Isfahan, after being transferred to the laboratory, the Stomatal density, total protein content, soluble sugars and anthocyanin were calculated.

The results showed that M. nigra and A. altissima species responded to air pollution by increasing and P. orientalis by reducing the density of stomata. The amount of total protein content of M. nigra, P. orientalis and A. altissima leaves were 48.93, 55.76 and 23.53% higher in polluted areas than in unpolluted areas. The value of soluble sugars and anthocyanins in M. nigra, P. orientalis and A. altissima leaves were found (90.22, 38.65 and 88.88) and (19.64, 88.8 and 80.05%) in polluted areas compared to non-polluted areas.

According to the findings, it can be concluded that trees have differently respond to air pollution in relation to stomata density, which can be done in two ways, increasing or decreasing stomata density. Increasing the amount of total protein, soluble sugars and anthocyanins in the leaves of trees in the polluted area indicates that these trees are tolerant to pollutants and they applied these useful strategies to adapt and deal with pollutants.