The influence of urban environment on pollen grains of the silver birch (<i>Betula pendula</i> Roth) in conditions of Yakutsk

Abstract

This paper studies variability of pollen grains of the silver birch in relation to the quality of urban environment. The material was collected in 12 sites. A total of 1,190 leaves and 24,000 pollen grains were examined and measured. The pollen fertility varied within 6992%. Statistically significant decrease in fertility was observed in conditions of high-intensity traffic load, in the central area of the city, and where the road surface was in poor condition. Under the same conditions a statistically significant increase in percentage of relatively fertile pollen grains is observed. We found significant correlation between the level of fluctuating asymmetry (FA) and the share of fertile and half-fertile pollen grains. For fertility Spearmans rho was 0,71; and for half-fertility, r = 0,66, p 0,05. A similarly significant correlation (r = 0,7, p 0,05) was found between the diameter of pollen grains and traffic load, which indicates a consistent organism response to environment deterioration. From the above, it follows that for assessment of environmental condition such characteristics of pollen grains as fertility, half-fertility, and pollen grain size can be used.