The effect of air pollution on crown and foliar nutrient conditions of forests in the Southern Turkey

In order to evaluate the alterations of the nutrient levels and crown conditions in the years 1992, 1993 and 1998, pine needles were taken from labelled conifer trees. Concentration variation of nutrient and trace elements in pine needles has been observed between the sites and years of observation. At selected sampling points, visual indices of tree conditions, like defoliation and discoloration or dry weight of the canopies were also reported. Between the years 1991 and 1997 the degree of defoliation and discoloration of the canopies according to the damage indices were seen to change from 10-25% to 25-60%.