Subdivisions of dark coniferous forests of North Eurasia for a Circumboreal vegetation map
Nikolai ERMAKOV
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.
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© 2012 Organizing Committee
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