The subzone description below lists Alaska plant communities along a toposequence on acidic and non-acidic substrates; in subzones C, D and E; in the three floristic provinces of Northern Alaska (
), Beringian Alaska (
) and Northern Beringian Island (
). Blocks of rows are positions along a mesotopographic gradient (see Mesotopographic gradient). Dominant plant functional types and species are listed where data were available. Literature citations (in small font) include unit names, habitat, citation and location.
| Habitat along the meso-topographic gradient | Acidic substrates
(community # 13-23) | Non-acidic substrates
(community # 24-34) |
|---|
| Dry exposed sites | 13. Map 2, Unit 6, evergreen dwarf shrub, dry stabilized sand dune crests (Komárková and Webber 1980) (Atqasuk).
Prostrate dwarf shrub:
Dryas integrifolia, Salix phlebophylla, Arctous rubra, Diapensia lapponica;
Lichen:
Alectoria nigricans
| 24. Stand Type B1 (Walker 1985); Stand Type Dryas integrifolis – Oxytropis nigrescens, dry calcareous gravelly soils (Walker 1990) (Prudhoe Bay).
Prostrate dwarf shrub:
Dryas integrifolia, Salix reticulata;
Sedge:
Carex rupestris;
Forb: Oxytropis nigrescens;
Lichen:
Lecanora epibryon, Pertusaria spp., Thamnolia subuliformis
|
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| 14. Vegetation of alpine areas and fell-fields (Young 1971) (St. Lawrence Island).
Graminoid:
Arctagrostis latifolia, Carex microchaeta ssp. nesophila, Hierochloe alpina, Trisetum spicatum;
Prostrate dwarf shrub:
Salix phlebophylla, Salix polaris;
Forb:
Minuartia arctica, Potentilla spp., Oxytropis nigrescens, Pedicularis lanata, Artemisia spp.
| 25. Devil's Upland, Seward Peninsula (Jorgenson 2001)
Prostrate dwarf shrub:
Dryas integrifolia;
Lichen
|
| 15. Dry flats, ridge tops & benches (Klein 1959) (St.Matthew Island).
Prostrate dwarf shrub:
Salix ovalifolia, S. fuscescens, Dryas octopetala;
Lichen:
Cladina stellaris, Sphaerophorus globosus, Flavocetraria cucullata;
Graminoid:
Carex microchaeta ssp. nesophila
| 26. (dry limestone slopes, York Mtns., Seward Peninsula).
no data - probably similar to Subzone E, community 73, this table.
Prostrate dwarf shrub,
forb,
lichen
|
| Moist sites | 16. Map 2, Unit 8, mesic stabilized sands (Komárková and Webber 1980) (Atqasuk).
Tussock sedge:
Eriophorum vaginatum;
Erect dwarf shrub:
Ledum decumbens, Vaccinium vitis-idaea;
Lichen:
Cladina rangiferina, Ochrolechia frigida spp.;
Moss:
Dicranum spp., Sphagnum compactum
| 27. Northern Alaska: Stand Type U3, mesic nonacidic loess (Walker 1985) (Prudhoe Bay).
Beringian Alaska: Map unit 42A - low shrub water sedge tussock tundra (Swanson and Schuman 1985) (Seward Peninsula).
Sedge:
Carex bigelowii, Eriophorum angustifolium ssp. triste, E. vaginatum, Carex membranacea, C. aquatilis;
Prostrate dwarf shrub:
Dryas integrifolia, Salix reticulata;
Erect dwarf shrub:
Salix richardsonii;
Forb:
Tephroseris frigida, Eutrema edwardsii, Papaver macounii spp. discolor, Leucanthemum integrifolium, Pedicularis lanata, Tofieldia pusilla;
Moss:
Tomentypnum nitens, Drepanocladus brevifolius, Distichium capillaceum, Ditrichum flexicaule, Hypnum bambergeri;
Lichen:
Thamnolia subuliformis, Flavocetraria cucullata, Cetraria islandica
|
|---|
| | 27 (cont). Map unit 42A - low shrub water sedge tussock tundra (Swanson and Schuman 1985) (Seward Peninsula).
|
| 17. 42B- low shrub cottongrass tussock tundra (Swanson and Schuman 1985)
(Seward Peninsula).
Tussock sedge:
Eriophorum vaginatum, Carex bigelowii;
Dwarf shrub:
Ledum palustre ssp. decumbens;
Moss:
Polytrichum spp., Sphagnum spp.;
Lichen:
Cetraria spp., Cladina spp.
|
28. Vegetation of alpine areas and fell- fields (Young 1971) (St. Lawrence Island).
Graminoid:
Deschampsia caespitosa, Juncus biglumis, Luzula confusa;
Shrub:
Salix phlebophylla, Salix polaris;
Forb:
Huperzia selago, Oxyria digyna, Saxifraga nelsoniana, Rhodiola integrifolia, Cassiope tetragona, Primula tschuktschorum, Artemisia arctica
|
| 18. Vegetation
of mesic tundra (Young 1971) (St. Lawrence Island).
Graminoid:
Calamagrostis canadensis var. langsdorfii, Juncus castaneus;
Prostrate dwarf shrub:
Rubus arcticus;
Forb:
Comarum palustris, Epilobium anagallidifolium
| |
| 19. Moist
well-drained meadows (Klein 1959) (St. Matthew Island).
Sedge:
Carex microchaeta ssp. nesophila, Alopecurus alpinus, Arctagrostis latifolia;
Prostrate dwarf shrub: Salix rotundifolia, S. reticulata;
Forb
|
| Wet sites | 20. Northern Alaska: Map 2, Unit 16, wet marshes (Komárková and Webber 1980) (Atqasuk).
Beringian Alaska: Water sedge wet meadow (Racine and Anderson 1979); Map Unit 55- cottongrass-water sedge, low-centered polygons (Swanson and Schuman 1985) (Seward Peninsula).
Northern Beringian Islands: Vegetation Type wet tundra (Young 1971) (St. Lawrence Island).
Sedge:
Carex aquatilis, Carex spp., Eriophorum angustifolium spp.;
Moss:
Drepanocladus spp., Sphagnum spp.
| 29. Stand Type M2, wet calcareous meadows, ice-wedge polygon centers, lake margins (Walker 1985) (Prudhoe Bay).
Sedge:
Carex aquatilis, Eriophorum angustifolium spp., Carex spp.;
Moss:
Drepanocladus brevifolius, Scorpidium scorpioides, Cinclidium latifolium, Meesia triquetra, Catoscopium nigritum, Distichium capillaceum
|
|---|
| 20 (cont). Water sedge wet meadow (Racine and Anderson 1979); Map Unit 55- cottongrass-water sedge, low-centered polygons (Swanson and Schuman 1985) (Seward Peninsula).
| |
| 20 (cont). Vegetation Type wet tundra (Young 1971) (St. Lawrence Island).
|
| Snow beds | 21. Boykinia richardsonii-Cassiope tetragona comm. Map 2, Unit 11, early-melting snow beds (Komárková and Webber 1980) (Atqasuk).
Hemiprostrate dwarf shrub:
Cassiope tetragona;
Forb:
Boykinia richardsonii
| 30. Stand Type U6 ; Stand type Cassiope tetragona-Dryas integrifolia, early melting nonacidic snowbeds on pingos (Walker 1990) (Prudhoe Bay).
Hemiprostrate dwarf shrub:
Cassiope tetragona;
Prostrate dwarf shrub:
Dryas integrifolia, Salix reticulata,
Sedge:
Carex scirpoidea;
Forb:
Pedicularis capitata, Bistorta vivipara, Silene acaulis, Papaver macounii spp. discolor;
Moss:
Ditrichum flexicaule, Sanionia uncinata, Tomentypnum nitens;
Lichen:
Cetraria cucullata, Masonhalea richardsonii, Cetraria nivalis, Peltigera canina
|
|---|
| | 31. Stand Type U7 (Walker 1985) ; Facies Salix rotundifolia-Eriophorum triste, late-melting nonacidic snowbeds (Walker 1990) (Prudhoe Bay).
Prostrate dwarf shrub:
Salix rotundifolia;
Sedge:
Carex aquatilis, Eriophorum angustifolium ssp. triste;
Horsetail:
Equisetum scirpoides, Equisetum variegatum;
Moss:
Distichium capillaceum, Ditrichum flexicaule
|
| Riparian areas | 22. Map 2 Unit 17, Decidious scrub, sandy floodplains (Komárková and Webber 1980) (Atqasuk).
Low shrub:
Salix alaxensis, S. richardsonii, S. glauca, S. pulchra;
Forb:
Eurybia sibirica, Astragalus alpinus, Tanacetum bipinnatum, Bistorta vivipara, Pedicularis capitata, Equisetum variegatum, Equisetum arvense
| 32. Stand Type B4, active floodplains (Walker 1985) (Prudhoe Bay); Epilobio-Salicetum alaxensis (Schickhoff et al. 2002) (Sagavanirktok River).
Forb:
Epilobium latifolium, Artemisia arctica, Artemisia borealis, Papaver lapponicum, Polemonium boreale, Astragalus alpinus, Wilhelmsia physodes, Parrya nudicaulis, Castilleja caudata, Hedysarum alpinum, Hedysarum mackenziei;
Dwarf shrub:
Salix alaxensis
|
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| 23. Low-medium willow shrub thicket (Racine and Anderson 1979); Map unit 34- low shrub - floodplain (Swanson and Schuman 1985) (Seward Peninsula).
Low shrub:
Salix pulchra;
Moss:
Hylocomium splendens;
Lichen:
Cetraria islandica, Cladina spp.
| 33. Stand Type U8, moist streamsides on fine grained soils (Walker 1985) (Prudhoe Bay); Anemeno-Salicetum richardsonii (Schickhoff et al. 2002) (Sagavanirktok River).
Low shrub:
Salix richardsonii, S. alaxensis, S. glauca;
Sedge:
Carex aquatilis, Eriophorum angustifolium spp.;
Forb:
Polemonium acutiflorum, Cardamine microphylla ssp. blaisdellii , Pedicularis albolabiata
|
| | 34. Dryas integrifolia-Lupinus arcticus comm., dry river terraces (Walker et al. 1997) (Happy Valley).
Dryas terrace comm. (Jorgenson pers.comm.) (Arctic NWR).
Prostrate dwarf shrub:
Dryas integrifolia, Arctous rubra, Salix reticulata;
Erect dwarf shrub:
Salix richardsonii, Vaccinium uliginosum;
Forb:
Anemone parviflora, Bistorta vivipara, Castilleja caudata, Lupinus arcticus, Oxytropis campestris, Pedicularis capitata;
Sedge:
Carex scirpoidea, C. rupestris; Horsetail:
Equisetum variegatum,
Moss:
Rhytidium rugosum;
Lichen:
Flavocetraria cucullata, Flavocetraria nivalis, Cladonia pocillum, Dactylina arctica, Masonhalea richardsonii, Peltigera canina, Thamnolia subuliformis
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