Circumpolar Arctic Vegetation Unit S1

 

Hierarchy of Geobotanical Vegetation Map Units (Walker DA 2002)

Daring Lake, Canada. Photo D.A. Walker.
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map legend color for unit S1S1. Erect dwarf-shrub tundra

Tundra dominated by erect dwarf-shrubs, mostly <40 cm tall. Subzone D.

Detailed Description

Moist to dry tundra in Subzone D on acidic soils, dominated by hemiprostrate and erect dwarf shrubs <40 cm tall. This is the zonal vegetation in acidic and oceanic areas of Subzone D in Greenland and the Canadian Shield. Drier, lichen-rich dwarf-shrub tundras are common in many areas, e.g., the sandy soils of the Yamal and Gydan peninsulas in Russia, and in a matrix with lichen-covered bedrock on the Canadian mainland and Baffin Island. Plant cover is continuous (80-100%) on zonal sites to sparse (5-50%) on dry ridges.
Area: 689 x 1000 km2.

Representative Syntaxa

Communities of the class Loiseleurio-Vaccinietea, Phyllodoco-Vaccinionmyrtilli Nordh. 1936, e.g., Phyllodoco-Salicetum callicarpaeae (Böch. 1933) Dan. 1982 and Empetrum-Vaccinium community Dan. 1982 (Greenland).

Dominant Plants

Dwarf-shrubs, mosses, and lichens are common.

    1. Dwarf shrub: Betula nana s.l. ; Betula middendorfii/glandulosa ; Vaccinium uliginosum ssp. microphyllum ; Vaccinium vitis-idaea ; Ledum palustre spp. decumbens ; Empetrum ; Salix glauca ; Salix callicarpaea ; Arctous ; Cassiope tetragona ;
    2. Moss: Hylocomium splendens ; Aulacomnium turgidum ; Dicranum ; Racomitrium lanuginosum ;
    3. Lichen: Stereocaulon ; Cladonia ; Flavocetraria ; Alectoria ochroleuca ; Masonhalea richardsonii ; Bryocaulon divergens ;

a=acidic, n=non-acidic