Print Report
A4331 Arctic Nonacidic Lichen - Sparse Dwarf-shrub Tundra Alliance
Type Concept Sentence: This group is characterized by lichen cover >25% or a sparse cover (<25%) of dwarf-shrubs that may or may not include lichens in the lowlands, hills and mountains of arctic and the alpine of subarctic Alaska.
Common (Translated Scientific) Name: Arctic Nonacidic Lichen - Sparse Dwarf-shrub Tundra Alliance
Colloquial Name: Arctic Nonacidic Lichen - Sparse Dwarf-shrub Tundra
Hierarchy Level: Alliance
Type Concept: This is a common group on acidic and basic substrates in the hills and mountains of arctic and subarctic Alaska and Canada, and possibly in the arctic lowlands. Common slope positions include valleys, sideslopes, and summits and ridges. The canopy is sparse due to extreme exposure and stands occur on exposed bedrock or unstable substrates. Sites are typically dry to mesic. Soils are typically thin, stony, and well-drained. Patch size is small to matrix-forming. Total vascular plant cover is less than 25%, and lichen and moss cover are variable, but often exceed 25%. Common dwarf-shrub species include Dryas octopetala, Empetrum nigrum, Vaccinium uliginosum, Dryas integrifolia, Loiseleuria procumbens, and Salix phlebophylla. Herbaceous species may include Antennaria alpina, Anthoxanthum monticola ssp. alpinum, Minuartia obtusiloba, Carex scirpoidea, Carex microchaeta, Lupinus arcticus, and Festuca altaica. Foliose and fruticose lichens may dominate and include Umbilicaria spp., Rhizocarpon geographicum, Cladonia stellaris, Racomitrium lanuginosum, Flavocetraria spp., and Alectoria ochroleuca.
Diagnostic Characteristics: This group represents areas within the arctic and subarctic regions of North America where vascular plant species have sparse cover (2-25%), very low vertical structure (<20 cm tall) with moss and lichen cover exceeding 25% cover.
Rationale for Nominal Species or Physiognomic Features: No Data Available
Classification Comments: Note that Raynolds et al. (2006a) do not map the CAVM type B1 in Alaska. This lichen community occurs in patches that are too small to map at the circumpolar scale. There is only one patch large enough to map at 1:4 M for Alaska - lava in central Seward Peninsula (M. Raynolds pers. comm. 2012). CAVM type B1 is a barren, cryptogam and cushion forb vegetation type lacking all shrubs, and occurs only in the High Arctic. Alpine areas in more southern parts of the Arctic that have cryptogam-dominated vegetation occur in patches that are too small to map at the circumpolar scale, and are thus included in a mountain complex type (B3 or B4) (M. Raynolds pers. comm. 2012). The applicability of this group concept in Canada needs critical review.
Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: This group is defined by a short-shrub layer of broad-leaved deciduous species not exceeding 25% cover with lichen species exceeding 25% cover.
Floristics: Foliose and fruticose lichens may dominate and vary with substrate. Umbilicaria spp. and Rhizocarpon geographicum are common on rocks. Lichens found growing on soil can include Cladonia stellaris, other Cladonia spp., Flavocetraria spp., Alectoria spp., Bryocaulon divergens, Pseudephebe spp., Thamnolia spp., Stereocaulon spp., and Masonhalea richardsonii. Racomitrium lanuginosum is the most common moss found in this type. Characteristic shrub species may include Dryas octopetala, Empetrum nigrum, Vaccinium uliginosum, Dryas integrifolia, Loiseleuria procumbens, and Salix phlebophylla. Herbaceous species may include Antennaria alpina, Anthoxanthum monticola ssp. alpinum, Minuartia obtusiloba, Saxifraga spp., Silene acaulis, Carex scirpoidea, and Carex microchaeta. The clubmoss Selaginella sibirica is also common.
Dynamics: No Data Available
Environmental Description: This is a common group on acidic and basic substrates in the hills and mountains of arctic and subarctic North America. Common slope positions include sideslopes, and summits and ridges. The canopy is sparse due to extreme exposure, exposed bedrock or unstable substrates. Sites are typically dry to mesic. Soils are typically thin, stony, and well-drained. Patch size is small to matrix-forming.
Geographic Range: This group occurs throughout arctic and subarctic Alaska, and possibly much of Canada and into Greenland.
Nations: CA,GL?,IS,NO,RU,US
States/Provinces: AK, LB?, MB, NT?, NU?, QC?, YT?
Plot Analysis Summary:
http://vegbank.org/natureserve/ELEMENT_GLOBAL.2.1042040
Confidence Level: Low
Confidence Level Comments: No Data Available
Grank: GNR
Greasons: No Data Available
| Type | Name | Database Code | Classification Code |
|---|---|---|---|
| Class | 4 Polar & High Montane Scrub, Grassland & Barrens Class | C04 | 4 |
| Subclass | 4.B Temperate to Polar Alpine & Tundra Vegetation Subclass | S12 | 4.B |
| Formation | 4.B.2 Polar Tundra & Barrens Formation | F031 | 4.B.2 |
| Division | 4.B.2.Xa Arctic Tundra & Barrens Division | D044 | 4.B.2.Xa |
| Macrogroup | 4.B.2.Xa.2 Feltleaf Willow - Eight-petal Mountain-avens - Tussock Cottongrass Tundra Macrogroup | M173 | 4.B.2.Xa.2 |
| Group | 4.B.2.Xa.2.b Arctic Dwarf-shrub Tundra Group | G896 | 4.B.2.Xa.2.b |
| Alliance | A4331 Arctic Nonacidic Lichen - Sparse Dwarf-shrub Tundra Alliance | A4331 | 4.B.2.Xa.2.b |
Concept Lineage: No Data Available
Predecessors: No Data Available
Obsolete Names: No Data Available
Obsolete Parents: No Data Available
Synonomy: > Alpine Syntaxa 33-35 xeric limestone rocks, Syntaxa 39-42 lichen heath, Syntaxa 47-49 occurring on granite boulders (Cooper 1986c)
> B2.1 - Lichen communities (#74) growing on lava in the central Seward Peninsula (Raynolds et al. 2006a)
> III.C.2.b - Foliose and fruticose lichen (Viereck et al. 1992) [Type is described as being in southwest and northwest Alaska on fell-fields and exposed ridges, and slightly more amenable to plant growth than those occupied by crustose lichens (III.C.2.a), which are reported by Viereck et al. for alpine habitats.]
> B2.1 - Lichen communities (#74) growing on lava in the central Seward Peninsula (Raynolds et al. 2006a)
> III.C.2.b - Foliose and fruticose lichen (Viereck et al. 1992) [Type is described as being in southwest and northwest Alaska on fell-fields and exposed ridges, and slightly more amenable to plant growth than those occupied by crustose lichens (III.C.2.a), which are reported by Viereck et al. for alpine habitats.]
- Cooper, D. J. 1986c. Arctic-alpine tundra vegetation of the Arrigetch Creek Valley, Brooks Range, Alaska. Phytocoenologia 14(4):647-555.
- Faber-Langendoen, D., J. Drake, M. Hall, G. Kittel, S. Menard, C. Nordman, M. Pyne, M. Reid, M. Russo, K. Schulz, L. Sneddon, K. Snow, and J. Teague. 2013-2019b. Screening alliances for induction into the U.S. National Vegetation Classification: Part 1 - Alliance concept review. NatureServe, Arlington, VA.
- Raynolds, M. K., D. A. Walker, and H. A. Maier. 2006a. Alaska Arctic Tundra Vegetation Map. Scale 1:4,000,000. Conservation of Arctic Flora and Fauna Map No. 2. U.S. Fish & Wildlife Service, Anchorage, AK.
- Raynolds, M. K., D.A. Walker, and H. A. Maier. 2006b. NDVI patterns and phytomass distribution in the circumpolar Arctic. Remote Sensing of Environment 102:271-281. [http://www.geobotany.org/library/pubs/RaynoldsMK2006_rse_102_271.pdf]
- Raynolds, Martha. Personal communication. Research Biologist, University of Alaska, Fairbanks, AK.
- Viereck, L. A., C. T. Dyrness, A. R. Batten, and K. J. Wenzlick. 1992. The Alaska vegetation classification. General Technical Report PNW-GTR286. USDA Forest Service, Pacific Northwest Research Station, Portland, OR. 278 pp.