The use of birch Betula pubescens folia morphology as indicator of atmosphere pollution and anthropogenic pressure

The increase of anthropogenic pressure and permanent pollution of the natural and urbanized environment requires the availability of effective methods for monitoring the ecological quality of territories. The priority should be considered simple, cheap and knowledge-intensive methods that can be owned by researchers without special environmental education. Such methods are the methods of phenogenetic indication and assessment of the morphological variability of widespread plants. Contaminants and pollutants can be divided into 4 categories: toxins, teratogens, carcinogens and mutagens. Toxins inhibit the development of organisms, but do not affect their genetic program. Teratogens disrupt the implementation of the genetic program. Mutagens and carcinogens destroy the genetic program itself, and these disorders can be passed on to the next generation. A convenient object of express monitoring is the birch Betula pubescens (alba) L, which is widespread in Eurasia. Toxic emissions destroy its growth and normal ontogenesis. The variability of the linear parameters of the leaves increases under environment stress. Teratogens increase the proportion of trees with dichotomy and trichotomy. The indicator of fluctuating asymmetry of leaves can serve as a criterion for mutagenic pollution of the environment. This paper presents estimates of morphological variability in different places of the Leningrad region. The coefficient of fluctuating asymmetry KA = (l₁ - l₂)² / (l₁ + l₂) is introduced, where l₁ and l₂ are linear indicators of asymmetry. A high correlation was established between the level of diversity and the distance from the motorways and pollution by lead compounds, which is a teratogen. Fluctuating asymmetry is increased in places of radioactive contamination, depends on the distance to the trace of the Chernobyl disaster, the nuclear power plant. It is also increased in places of natural increased background radiation associated with the outputs of radioactive radon and the presence of granites. A map of the distribution of vegetation with varying degrees of morphological diversity and fluctuating asymmetry is presented. It is proposed to use the developed methods and algorithms for the assessment of toxic, teratogenic and mutagenic pollution of the environment and for the ecological monitoring of urbanized and non-urban areas.