XVI International Botanical Congess

Heavy metal pollution is one of the most serious environmental problems of today and the effects of heavy metal pollution have become increasingly important in ecophysiological studies. The purpose of this study is to detect toxic effects of Cd and Pb in the coniferous tree species of Istanbul city. In general, chlorophyll content was decreased and peroxidase activity was increased in the needles, and the annual rings were narrowed with higher concentrations of Cd and Pb. Two year old needles were affected more negatively than the one year old ones and P.nigra species were found more tolerant to pollution than P.excelsa, P.pinea, C. libani, and C. deodora species.