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Wetland Classification and Mapping of the Kenai Lowland, Alaska
Map Unit Descriptions
Ecosystem: Relict Glacial Drainageway Map Component: DW5A5; DW55A
Extent: DW55A: 88 wetland polygons; 653.5 ha; 0.46% of wetland area; 0.53% of wetland polygons. DW5A5: 66 wetland polygons; 844.3 ha; 0.60% of wetland area; 0.40% of wetland polygons. |
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A DW55A unit near South Fork Deep Creek (polygon 2178).
A DW5A5 unit in the City of Kenai (polygon 8417). |
Wetland Indicators Type: Mineral, or Peat Average depth to water table: DW5: 37.4 cm; n=14 DW5A: 38.8 cm; n=24 Organic layer thickness: DW5: 78.2 cm; n=14 DW5A: 46.3 cm; n=24 Average depth to redoximorphic features: DW5: 135.0 cm at the single site measured DW5A: 60.7 cm; n=3 Common Soils: DW5: NIKOLAI, STARICHKOF, TRUULI DW5A: TRUULI, NIKOLAI, STARICHKOF, Common Plant communities: DW5 component: Sphagnum moss - Ericaceous shrub Lutz spruce / Barclay willow / Field horsetail / Crowberry DW5A component: |
| Accuracy assessment: 12 polygons interpreted as DW55A on aerial photographs were field checked. 5 remained DW55A; 1 each was revised to DW25, DW35A, DW45A, RB and SLM. 2 were revised to Rea. 8 polygons interpreted as DW5A5 on aerial photographs were field checked. 4 remained DW5A5, 1 each was revised to: DW55A, DWR, LB64 and LB6. | |
DW5A5 and DW55A wetlands are forest or woodland complexes on a variety of landscape features. They occupy underfit stream valley and relict drainageway margins, connectors between kettles on a kettle-kame landscape, or they cross the divide between two streams or relict drainageways. DW5 and DW5A are the highest and driest relict drainageway components, frequently occupying the transition zone between wetlands and uplands.
These units are widespread. On the northern peninsula they are dominated by black spruce (Picea mariana) and sphagnum moss - shrub communities; in the south Lutz spruce (P. X lutzii) and Barclay willow (Salix barclayi) are more common.
DW5A is the forested component, while DW5 indicates a deeper water table, and is often dominated by sphagnum moss / shrub communities, but sometimes by Barclay willow types. They are often mixed with open shrubby patches in a matrix of forest or woodland. When forest is dominant, DW5A5 is assigned; when the forest is in scattered patches, DW55A.
