Syntaxonomical survey of boreal oligotrophic pine forests in northern Europe and Western Siberia

Question: What is the syntaxonomical diversity of boreal oligotrophic pine forests in Western Eurasia? Location: Boreal zone of Northern Europe and Western Siberia. Methods: Classification of forest vegetation plots using Ward's clustering and the Braun-Blanquet approach. Results: North European and West Siberian boreal oligotrophic pine forests can be assigned to the Vaccinio-Piceetea Br.-Bl. in Br.-Bl. et al. 1939; Pinetalia sylvestris Oberdorfer 1957; Cladonio stellaris-Pinion sylvestris Kielland-Lund ex Ermakov et Morozova 2011, seven associations (Cladonio arbusculae-Pinetum sylvestris (Kielland-Lund 1967) Ermakov & Iirozova 2011; Flavocetrario nivalis-Pinetum sylvestris Morozova et al. 2008; Pinetum sibiricae-sylvestris Makhatkov et Ermakov 2010; Hedysaro alpini-Laricetum sibiricae Saburov 1972; Linnaeo borealis-Pinetum sylvestris (Kielland-Lund 1967) Ermakov & Iirozova 2011; Barbilophozio-Pinetum sylvestris Br.-Bl. et Sissingh in Br.-Bl. et al. 1939; Bazzanio-Pinetum sylvestris Kielland-Lund 1967; Calamagrostio lapponicae-Pinetum sylvestris Br.-Bl. et Sissingh in Br.-Bl. et al. 1939) and six subassociations. Syntaxonomical and geographical boundaries between the alliances Cladonio stellaris-Pinion sylvestris and Dicrano-Pinion (Libbert 1933) Matuszkiewicz 1962 were defined. Conclusion: We propose the concept of alliance Cladonio stellaris-Pinion sylvestris, which includes all associations of oligotrophic pine forests within the boreal zone of Europe and Western Siberia. Analysis of a data set from Northern Europe and North-western Siberia demonstrates a common set of ecological, floristic and phytocoenotic features of all types of oligotrophic pine forests. This supports Oberdorfer's concept of a single Eurasian order Pinetalia sylvestris.