The introduction of the wood inroducents in the undergrowth structure of the of forest parks of the city Yekaterinburg
The Yekaterinburg city is surrounded by 14 forest parks (12.6 thousand hectares). Forest parks arose in the end of the 20s of XX century. In 1934 on the surrounding area of Sverdlovsk by the allocation of 4 forest plantations was initiated the construction of a forest-park zone. The natural processes disruption in forest plantations around the cities comes out in the displacement of aboriginal species peculiar to the southern taiga subzone and the introduction of new arboreal taxa of foreign district origin. The coenopopulations density of aboriginal and introduced undergrowth species can serve as an indicator of the anthropogenic transformation of plantations of the forest park zone. By the route survey and laying of six test areas was identifi ed 18 species of introducents of 23 genera of 10 families introduced under the canopy of the overripe arboreal plantations. In the undergrowth of the forest park named after the Foresters of Russia was marked the expansion of 14 arboreal introducents, in Uktussky forest park 11 species of the foreign district origin rooted under the canopy of overripe pine plantations. Invasive species belong to 23 genera of 10 families. Species of the Rosaceae family prevail: Cotoneaster melanocarpus Fisch. ex Blytt, Sorbaria sorbifolia (L.) A. Br, Malus baccata (L.) Borkh. The highest coenopopulation density of aboriginal species (999 pcs/ha) was detected for the Sorbariasorbifolia (L.) A. Br in the Uktussky forest park. In the forest park named after the Foresters of Russia the highest density (566 pcs/ha) was detected for the Prunuspadus L. The optimal closeness of the arboreal canopy for the new undergrowth species resettlement is 0.6 in the forest park named after the Foresters of Russia. The transformation of the species composition of the undergrowth comes out in the free space capture and its retention for a long time by naturalized introducents. The absence of Chamaecytisus ruthenicus (Fisch. ex Wol.) Klask. in the undergrowth and a decrease of Rosaacicularis Lindl. in the amount per 1 ha over the past 50 years indicate an anthropogenic change in its composition. The introduction of arboreal introducents under the canopy of old-age pine plantations does not pose a danger to natural phytocenoses.