Ecological and physiological state of <i>Betula pendula</i> and <i>Populus balsamifera</i> in anthropogenic environment

The vital state and the dynamics of ascorbic acid and tannins content in leaves of Betula pendula Roth. and Populus balsamifera L., growing in the streetside plantings of the Lower Kama region of the Republic of Tatarstan – the town of Yelabuga and the city of Naberezhnye Chelny were studied. In the streetside plantings of Yelabuga and Naberezhnye Chelny, the studied species showed a decrease in their vital state compared to the control, which indicates a similar level of negative impact. Under the anthropogenic stress in leaves of the studied species, an increase in the content of ascorbic acid is observed in the initial stages of vegetation, and of tannins - by its end, which indicates the protective role of the latter closer to the end of growing season. A higher content of ascorbic acid in the studied species was registered in the city of Naberezhnye Chelny, compared to the town of Yelabuga, which indicates a more active response against higher anthropogenic load in bigger city.