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Wetland Classification and Mapping
of Seward, Alaska An extension of wetland classification and mapping of the Kenai Lowland
Map Unit Descriptions Ecosystem: Depression Map Units: D32, D23
Seward Area Extent: D32: 2 wetland polygons; 5.2 acres. D23: 2 wetland polygons; 2.1 acres. |
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 A mixed D32 Depression dominated by dwarf birch, crowberry, bog blueberry and fewflower sedge, near the Snow River. A few low spots dominated by tufted bulrush and tall cottongrass have a shallower water table. |
Wetland Indicators Type: Peat, or mineral Average depth to water table: 20 cm Organic layer thickness: 150+ cm, at the single peatland, and 20 cm at the single mineral soil wetland measured Average depth to redoximorphic features: n/a if peat, 8 cm in the single mineral soil wetland measured Common Soils: Typic Cryohemists, Typic Cryaquods Common Plant communities: D2 component: Tufted bulrush - dwarf birch (Tricophorum caespitosum - Betula nana) Sphagnum - tall cottongrass (Sphagnum spp. - Eriophorum angustifolium) D3 Component: Crowberry - Labrador tea (Empetrum nigrum - Ledum palustre spp. decumbens) Sphagnum - Ericad (Sphagnum spp. - Ericaceous shrub) Fewflower sedge - Dwarf birch (Carex pauciflora - Betula nana) NWI: PSS,EM1 HGM: Terrene Basin Isolated. |
These are uncommon peatlands with mixed sedge (D2) and shrub-dominated (D3) components in bedrock depressions not hydrologically connected at or very near the surface with other wetlands. Sedge-dominated components have a water table at or near the surface for most of the growing season, and shrubby components (D3) have a deeper water table. These uncommon wetlands occur either on the bedrock ledges above the Snow River Valley, or on the bedrock knob north of Bear Lake.
