Alaska Arctic Plant Communities
- Bioclimate Subzones
- Floristic Provinces
- Lake Cover
- NDVI and Phytomass
- Substrate Chemistry
- AATVM Cites
24. Dryas integrifolia-Carex rupestris
Photo A. Dryas integrifolia-Carex rupestris community on pingos at Prudhoe Bay, Alaska. Walker slide 74-12-8. Photo D.A. Walker.
Photo B. Detail showing lichen-covered hummocks of Dryas integrifolia-Carex rupestris community. Walker slide 74-12-9. Photo D.A. Walker.
Photo D. Dry tundra on ridge near the Kaktakturuk River, Arctic National Wildlife Refuge. Walker slide 81-20-19. Photo D.A. Walker.
Summary of Habitat: Dry nonacidic tundra on gravels in subzones C and D
Common plant functional types and species:
Lichen: Lecanora epibryon; Pertusaria spp.; Ochrolechia frigida; Thamnolia subuliformis; Flavocetraria cucullata; Physconia muscigena; Flavocetraria nivalis; Hypogymnia subobscura; Cetraria islandica; Dactylina arctica; Cladonia pocillum; Bryocaulon divergens;
Sedge: Carex rupestris;
Forb: Oxytropis nigrescens; Saxifraga oppositifolia; Draba cinerea; Leucanthemum integrifolium; Papaver lapponicum; Lesquerella arctica; Pedicularis lanata; Pedicularis capitata; Silene acaulis; Minuartia arctica;
- This type occurs mainly on dry wind-exposed nonacidic gravelly sites. The plant canopy consists of a discontinuous mat of Dryas integrifolia, an abundance of lichens, a few cushion forbs such as Oxytropis nigrescens and Saxifraga oppositifolia and several other erect forbs. A high percentage of the soil is unvegetated or covered in white crustose lichens (e.g., Lecanora epibryon). The sedge Carex rupestris is constant.
- The community Dryas integrifolia-Carex rupestris embraces all of the diversity within the non-riparian nonacidic Dryas integrifolia group of communities. It excludes the Dryas communities on river terraces that have higher diversity of forbs and erect shrubs (Community 34 and Community 83), and the communities on cryoturbated moister soils that lack Carex rupestris (Community 8). Similar Dryas communities occur within bioclimate subzones C and D of the Canadian archipelago (e.g., Dryas integrifolia-Carex rupestris comm. described from several studies in Arctic Canada and Greenland (e.g., Vonlanthen et al. 2008 (10 relevés); Schweingruber 1997; Thannheiser 1988; Thannheiser and Geesink 1990; Gonzalez et al. 2000, Victoria Island, Mount Pelly, V-CB-01, 05; Carici-Dryadetum integrifoliae (Daniëls 1982) described from Greenland). It is a nonacidic counterpart to Luzula confusa-Sphaerophorus globosus which occurs on dry acidic sites (Community 13).
- M.D. Walker (1990) sampled 77 stands on exposed north and ENE slopes of 41 pingos of the central Arctic coastal plain. 72 of these were nonacidic. Within the broad nonacidic group that she called Dryas integrifolia-Lecanora epibryon, she identified 3 distinct stand types: (1) Stand Type Cerastium beeringianum-Minuartia rubellum (5 relevés) occurred in very exposed sites near the coast; (2) Stand Type Dryas integrifolia-Oxytropis nigrescens (37 relevés) was the most common type — occurring mostly on north-facing exposed sites and best drained sites in and around Prudhoe Bay; (3) Stand Type Dryas integrifolia-Astragalus umbellatus (31 relevés) occurred on somewhat warmer less exposed sites with moister soils and higher diversity of herbs (e.g., Astragalus umbellatus, Papaver macounii, Parrya nudicaulis, Oxytropis jordalii, Carex scirpoidea).
Other names from the Alaska literature:
- Stand Type B1, Dry Dryas integrifolia, Carex rupestris, Oxytropis nigrescens, Lecanora epibryon dwarf shrub, crustose lichen tundra, 6 relevés, Prudhoe Bay, D.A. Walker (1985).
- Stand Type Dryas integrifolia-Oxytropis nigrescens, 37 relevés, Central Arctic Coastal Plain pingos, M.D. Walker (1990).
- The Dryas integrifolia-Carex rupestris community is more or less equivalent to Association Carici-Dryadetum integrifoliae (Daniëls 1982) described from Greenland. The Oxtropis nigrescens subtype would likely be defined as a subassociation.