Regularities of sinantropization processes of the vegetation cover in the cities of the south Cis-Urals (Bashkortostan Republic)

Increase of anthropogenic pressure on nature ecosystems leads to synanthropization of flora and vegetation. A replacement of native species in communities with synanthropic ones, including alien species, takes place as well as a change of native plant communities by synanthropic ones, decrease of biodiversity, simplification of structure, decrease in efficiency and stability of plant communities (Gorchakovskij, 1999). Synanthropization as an indicator of anthropogenic transformation of vegetation is a traditional object of studies (Sudnik-Wojcikowska, 1988; Abramova, 2010; Abramova, Mirkin, 2000; Abramova, Mikhailova, 2003; etc.). The ratio of synanthropic and native flora species for an assessment of synanthropization level is usually used. The assessment of synanthropization level is the most important element of monitoring as it helps to estimate a degree of ecosystems disturbance and to develop a system of their rational use and protection.

Processes of synanthropization are most expressed in the towns. The towns are the heterotrophic ecosystems including uniform group of anthropogenically transformed communities formed on the residential, industrial, transport, agrarian, recreational territories where the  florogenesis and the phytocoenogenesis are highly specific (Burda, 1991; Ilminskikh, 1993). The urban environment can have the leveling impact on climatic factors therefore the floras of towns in different nature zones quite often have the common features (Ilminskikh, 1993). An increase of a syntaxonomic variety due to destruction of native vegetation is compensated by increase of synanthropic syntaxa number from the synanthropic classes of vegetation, and also communities of aggressive alien species which are combined with species of local flora. The regularities of synanthropization of urban flora and vegetation are less studied (Kowarik, 1990; Burda, 1991; etc.). Due to a growth of urbanization process around the world the studying of anthropogenic transformation of ve­getation cover is required.

The article is devoted to the analysis of regularities of synanthropization of plant cover in towns of the southern Cis-Urals belonging to the Southern industrial zone of Bashkortostan Republic. 3 towns — Sterlitamak, Salavat and Ishimbay representing different categories by their population size were chosen for an assessment of synanthropization level.

As a result of research of flora and vegetation of Bashkortostan towns conducted by us in 2009–2014 the urban vegetation geobotanical database of Cis-Urals towns was created. The assessment of synanthropization level was carried out on the basis of 1820  relevés. Vegetation classification of urban vegetation was done by the Braun-Blanquet method (Braun-Blanquet, 1964). “The deductive method” (Kopeсký, Hejný, 1974) was applied also. According to the results of classification the communities belonging to 6 classes of disturbed habitat vegetation (Stellarietea mediae, Artemisietea vulgaris, Polygono arenastri–Poëtea annuae, Polygono-Artemisietea, Galio-Urticetea, Bidentetea tripartitae) and to 5 classes of native and semi-native vegetation (Lemnetea, Potametea, Phragmito–Magno-Caricetea, Molinio-Arrhenatheretea and Festuco-Brometea) were ana­lyzed.

It was noticed that communities of the vegetation classes growing on disturbed habitats in Cis-Urals towns are rather different by the levels of their synanthropization (56–97 %) and adventization (8–74 %). They indicate the processes of anthropogenic transformation of vegetation on urban areas, and their plant species play the important role in town floras.

Synanthropization level of communities of semi-natural and natural vegetation classes differs (20–49 %),­ but the level of their synanthropization and adventization in the towns is much higher than in other territories of the region.

The maximal values of synanthropization of the communities were described in larger towns of Sterlitamak and Salavat located in steppe zone and minimal — in Ishimbay town, located in a forest-steppe zone.

Representation in coenofloras of alien plant species increases from the medium-size towns to the large ones. 2 alien species are most widespread in the towns of the southern Cis-Urals: Acer negundo and Conyza canadensis which can be meet almost in all classes of the disturbed vegetation.

Thus, synanthropization process causes general degradation of towns as ecosystems. It is necessary to organize monitoring and management to decrease negative tendencies of losing phyto diversity, anthropogenic impact and recreation, introduction of alien species.

Key words: sinantropization, adventization, alien species, vegetation, cities, sytaxonomy, the south Cis-Urals

Section: Articles

How to cite

Golovanov Ya. M., Abramova L. M. 2016. Regularities of sinantropization processes of the vegetation cover in the cities of the south Cis-Urals (Bashkortostan Republic) // Vegetation of Russia. N 28. P. 28–36. https://doi.org/10.31111/vegrus/2016.28.28

Received July 1 2015

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