Technogenic stress and its effect on deciduous trees (an example from parks in Yaroslavl)

A comparative analysis of several morphological, physiological, and biochemical characteristics of leaves has been performed in birch (Betula pendula Roth), linden (Tilia cordata Mill.), and poplar (Populus nigra L.) trees growing in industrial areas of Yaroslavl with different levels of anthropogenic pollution. The results show that high concentrations of pollutants in the atmosphere suppress the growth of leaves, and the number and severity of necrotic lesions in them increase. Water content in leaves becomes lower, whereas ash content increases. The contents of photosynthetic pigments change as well: the leaves contain smaller amounts of chlorophylls a and b, whereas the accumulation of carotenoids increases. Judging from changes in the test parameters, P. nigra is more resistant to pollution than B. pendula and T. nordata.