Evaluation of Pollution Intensity in Different Districts of Tehran Based on Measuring Chlorophyll, Plumb and Cadmium Heavy Metal Contents in Trees

Abstract

Plane and Mulberry trees play a crucial role in purifying the polluted air in Tehran as a major<br />city. In this research, 13 main districts of Tehran city were chosen as study area. 20 completely healthy Plane<br />and Mulberry species were selected in similar ecological conditions and age range. The uptake of Cd and Pb<br />was determined using Spectrophotometry, whereas the Chlorophyll content was measured applying ICP<br />method. The statistical results of Chlorophyll data put the Mulberry and Plane trees of the studied district<br />into 9 classes (Dunkan statistical test). The statistical results put the studied districts in terms of amount of<br />Pb uptake in 3 classes for Plane trees and in 5 classes for Mulberry trees. The districts were classified in 5<br />classes for plane trees and in 4 classes for Mulberry trees in terms of amount of Cd uptake. In general, the<br />uptake content of Cd and Pb is higher in Plane trees in comparison with Mulberry ones. In other words, Plane<br />trees are more sensitive to the uptake of contaminants than Mulberry trees. Finally, GIS maps were designed<br />showing the average uptake of contaminates in each district.