|
Wetland Classification and Mapping
of Seward, Alaska
Map Unit Descriptions Ecosystem: Headwater Fen Map Units: H34; H43
Seward Area Extent: H34; 5 wetland polygons; 35.8 acres H43: 1 wetland polygon; 1.1 acres |
|
|
Mountain hemlock forest dominates the H4 foreground of this photo, with fewflower sedge (H3) in the openings behind.
|
Wetland Indicators Type: Peat or mineral soil Average depth to water table: 28 cm Organic layer thickness: 104 cm if peat, 13 if mineral soil Average depth to redoximorphic features: n/a, if peat, 20 cm if mineral soil Common Soils: Typic Cryohemists, Typic Cryosaprists, Terric Cryosaprists, if peat, Typic Cryaquents if mineral soil Common Plant communities: H3: Fewflower sedge (Carex pauciflora) H4: Mountain hemlock / early blueberry (Tsuga mertensiana / Vaccinium ovalifolium)
NWI: PSS1,3&4Eg (H3); PFO4Eg (H4) HGM: Terrene Basin groundwater-dominated Throughflow headwater. |
Mountain hemlock with an early blueberry understory in a Headwater Fen ecosystem wetland indicates H4. H3 fens are dominated by fewflower sedge. Where the forest predominates (at a single wetland) a fen is named H43, when sedge dominates it is named H34.
Headwater Fen Ecosystem wetlands are sloping peatland fens at or near the headwaters of first-order streams. Seward area Headwater Fens are mapped only on the 800' elevation glacier-cut bedrock bench above Fourth of July Creek.
