Phytosociological Analysis of the Boreal Oligotrophic Pine Forests in the Southern Ural Region (Russia)

Abstract

Floristic composition and syntaxonomy of the boreal oligotrophic pine forests covering vast areas in the boreal, hemiboreal, and temperate zones of continental Eurasia still remain poorly studied in the Southern Ural region. Using the Braun–Blanquet approach and TURBOVEG and JUICE software, the phytocoenotic diversity of boreal oligotrophic pine forests of the Southern Ural region was studied, and their position in the system of ecological and floristic classification of Eurasian vegetation was determined. Geobotanical data on boreal oligotrophic pine forests of Europe, including the European part of Russia; the Southern Urals; and Siberia were compared. A new alliance of oligotrophic boreal pine forests Brachypodio pinnati-Pinion sylvestris all. nov. hoc loco is described. The communities of this new alliance (i.e., five associations from the Southern Ural region) are characterized by a special floristic composition, occupying an intermediate position between the typical European oligotrophic pine forests of the alliance Dicrano-Pinion (Libbert 1933) Matuszkiewicz 1962 and oligotrophic (mainly psammophilous) South Siberian pine forests of the alliance Hieracio-Pinion Anenkhonov et Chytrý 1998. The communities of the alliance Brachypodio pinnati-Pinion sylvestris prefer to grow on poor soils with different moisture conditions. Due to intensive forestry activities, the distribution area of these forests has decreased, and these communities have been replaced by secondary birch forests. We have proposed a set of conservation measures to preserve these communities. A new association of oligotrophic pine forests Psephello sumensis-Pinetum sylvestris ass. nov. hoc loco is also described. These communities from the Kurgan region of Western Siberia were ordered into the alliance Dicrano-Pinion. It confirms the idea that the distribution area of this alliance may reach Siberia. Unlike the Southern Ural pine forests of the alliance Brachypodio pinnati-Pinion sylvestris, the recovery of these West Siberian pine forests after felling is quite high, and these communities do not require special measures for their protection.