Reduced stability of forest communities of the South Urals

The territory of the South Urals is considered to be an ecotone, with forest ecosystems, including the ones in Orenburg Region, differing from those in the European Russia, Siberia, the Far East etc. In the absence of agriculture, meadow steppe vegetation remains the major background of the forest-steppe zone, alternating with deciduous forest areas. The region locates the borders of natural distribution of some tree and shrud species of forest phytocenoses. The territory is regularly exposed to air, soil, water and groundwater pollution. The ecological situation observed in Orenburg Region is extremely unfavorable due to high content of heavy metals in rocks and groundwater and acute technogenic load. Technogenic land pollution leads to an increased number of territories contaminated with industrial wastes, petroleum and petroleum products, heavy metals, pesticides and other toxic substances, which creates extreme and critical conditions for trees and shrubs and overall forest ecosystems...