Subdivisions of dark coniferous forests of North Eurasia for a Circumboreal vegetation map

Central Siberian Botanical Garden, Novosibirsk, Russia

The dark coniferous forests of Eastern Europe and Northern Asia show disjunctive ranges. They are dominated by five main conifer species: Picea abies, P. obovata, P. jezoensis, Abies sibirica and Pinus sibirica. Generalization of the regional systems gives us an important knowledge on syntaxonomic status and plant-geographical peculiarities of the high-rank dark coniferous forests. At present, two orders, Piceetalia excelsae and Abieti nephrolepidis–Piceetalia jezoensis represent “western” and “eastern” geographical subdivisions of these forests. However plantgeographic analyses demonstrated the need to differentiate the Abieti-Piceetalia into “boreal” and “hemi-boreal” vegetation types. East Asian hemi-boreal alliances of the Abieti-Piceetalia should be included in the temperate higher syntaxa. Typical boreal East Asian dark-coniferous forests should be included in the Eurasian order – Piceetalia excelsae. The basis of this solution is a distinct floristic core of dark coniferous forests which is stable through the whole their range from the Atlantic to Pacific. These are mesic, moderately cold-resistant and shade-tolerant species of Eurasian and Eurasian-North American range: Athyrium filix-femina s.l., Dryopteris expansa s.l., Phegopteris connectilis, Diplazium sibiricum, Gymnocarpium dryopteris, Lycopodium annotinum, Oxalis acetosella, Sorbus sibirica, Maianthemum bifolium, Vaccinium myrtillus, Rhytidiadelphus triquetrus. Alliances demonstrate biogeographical differentiation of dark-coniferous forests:

- Piceion excelsae Pawl. et al. 1928 – southern-boreal forests of the main part of Europe;

- Aconito rubicundi–Abietion sibiricae Anenkhonov & Chytry 1998 – southern-boreal forests of Eastern part of Eastern Europe, Urals, Western and southern Siberia;

- Pino–Abietion sibiricae Ermakov & Makhatkov 2011 all. prov. – northern-boreal forests of Siberia;

- Pino pumilae–Piceion jezoensis Krestov & Nakamura 2002 – southern and middle-borteal forests of Kamchatka;

- Piceion jezoensis Suzuki-Tokio 1973 – south boreal forest of Sakhalin and Hokkaido;

- Abieti–Piceion jezoensis Song 1991 – south boreal forests of continental part of Far East.

© 2012 Organizing Committee