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Wetland Classification and Mapping of the Kenai Lowland, Alaska
Map Unit Descriptions Ecosystem: Relict Glacial Drainageway Map Unit: DWR
Extent: 98 wetland polygons; 1044.1 ha; 0.74% of wetland area; 0.59% of wetland polygons. |
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 A DWR unit in the city of Kenai (polygon 8415).
A DWR unit adjacent to the Kasilof River (polygon 9193). |
Wetland Indicators DWR is a complex of many possible components. The data below represent what was recorded at the four NRCS soil survey holes dug in wetlands assigned DWR. At NRCS holes, an attempt is made to characterize the surrounding area. Type: Peat and/or mineral. Average depth to water table: 10.8 cm; n=4 Organic layer thickness: 30.8 cm; n=4 Average depth to redoximorphic features: 45.0 cm at the single site recorded Common Soils: SLIKOK and MOOSE RIVER Common Plant communities: This is a varied complex, many plant communities are possible. These were the most common encountered on field visits: Barclay's willow / Bluejoint / Marsh fivefinger Water sedge / Marsh fivefinger
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| Accuracy assessment: 14 polygons interpreted as DWR on aerial photographs were field checked. 8 remained DWR; 1 each was revised to: DW23, DW32, DW3-5A, DW4-5A, DW55A and LBSF. | |
The name DWR is assigned when more than two non-consecutive Relict Glacial Draingeway ecosystem map components are present. This often occurs when wetter DW1, DW2 and/or DW3 components are present with a forested DW5A component. The missing component is typically DW4, the bluejoint grass (Calamagrostis canadensis) component, violating the naming rule that allows more than two components in a map unit name if they are consecutive.
DWR units are common and occur in a variety of landscape positions, but typically are present either as short first order drainages adjacent to a larger stream (both typically underfit), or in the area adjacent to the confluence of a larger stream with a major creek or river. They also often occupy small relict glacial valley bottom terraces adjacent to modern 'underfit' streams. In these positions the transition between upland to wetland is often abrupt, so many mapping components are present over a short distance. As such, these are, more or less, miscellaneous Relict Glacial Drainageway units, but do indicate that much beta diversity is present over a relatively small area.
