Dynamics of chlorophyll concentration in the birch (Betula pendula) leaves under the conditions of technogenic pollution in the city of Biysk

The article considers the results of biochemical studies of chlorophyll content in leaves of birch growing in different conditions in the city of Biysk: control, parks, squares, highways, petrol stations, factories, thermal power plants. In park areas, compared with the control, the content of chlorophylls a and b and the a / b ratio are lower. The best conditions for the growth of birch trees (closeness of crowns, distance from highways, and lower frequency of attendance) contribute to an increase in the content of chlorophyll a and b in the leaves. The sparse location of trees in squares and their intensive visits, emissions from industrial enterprises, cars and thermal power plants lead to a decrease in the content of chlorophyll a and b in the leaves. Regardless of the growing conditions, a regular increase in the content of chlorophyll a is observed during the growing season. A change in the content of chlorophyll a in birch leaves has been revealed; in the city of Biysk, it is changing downward in the following row of growing places: control -> parks -> squares -> highways -> petrol stations -> factories -> CHP. In dynamics by month, a slight increase in the concentration of chlorophylls in July was detected in all places of birch growth, and then its decrease in August.