|
Wetland Classification and Mapping
of Seward, Alaska
Map Unit Descriptions Ecosystem: Headwater Fen Map Units: H1-3; H31
Seward Area Extent: H1-3: 2 wetland polygons; 1.7 acres H31: 1 wetland polygon; 0.4 acres |
|
|
H1-3 includes the small pond (H1), low-lying sedge-dominated areas with a water table very near the surface, and fewflower sedge-dominated areas, which typically occupy areas with a deeper water table.
|
Wetland Indicators Type: Peat Average depth to water table: 10 cm Organic layer thickness: 146 cm Average depth to redoximorphic features: n/a Common Soils: Typic Cryohemists, Typic Cryosaprists, Terric Cryosaprists Common Plant communities: H1: Water horsetail (Equisetum fluviatle) H2: Sphagnum - Tall cottongrass (Eriophorum angustifolium) H3: Fewflower sedge (Carex pauciflora)
NWI: L2UB1 (H1); PEM1Bg (H2); PSS1,3&4Eg (H3) HGM: Terrene Basin groundwater-dominated Throughflow headwater. |
H1 is the Headwater Fen Ecosystem wetland component with open surface water. Near Seward, H3 is almost always indicated by a thick cover of fewflower sedge (Carex pauciflora). Some small ponds amidst a field of fewflower sedge occurs at the one wetland, named H31, on the glacier-cut bedrock bench above Fourth of July Creek. Low-lying wetter areas occupied by tall cottongrass (H2) occur along with ponds in a field of fewflower sedge at two other wetlands, named H1-3, on that bench.
Headwater Fen Ecosystem wetlands are peatlands 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.
