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Wetland Classification and Mapping
of Seward, Alaska
Map Unit Descriptions Ecosystem: Riparian Map Component: RB
Seward Area Extent: 16 wetland polygons; 86.9 acres |
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An RB flowing through a peatland on the bench above Fourth of July Creek. |
Wetland Indicators Type: Stream, a water of the U.S., not a 'wetland' Depth to water table: 14 cm at the one site visited on 26 July 2006 Organic layer thickness: 0 cm Depth to redoximorphic features: n/a Common Soils: Typic Cryaquents Common Plant communities:
Sitka spruce / Sitka alder (Picea sitchensis / Alnus viridis ssp. sinuata) Mountain hemlock / early blueberry (Tsuga mertensiana / Vaccinium ovalifolium)
NWI: Stream: R3US1. Adjacent valley wetlands: PSS1Jn HGM: Stream: Middle Gradient Natural Stream-single thread. Adjacent valley wetlands: Lotic Slope groundwater-dominated Throughflow/Bidirectional-nontidal. |
RB stream reaches are in Rosgen's (1996) 'B' stream category. B streams are moderately entrenched, of moderate gradient (2-4%), and dominated by riffles. RB includes the frequently narrow adjacent wetland stream valley.
Lost Creek and Spruce Creek are the largest RB streams around Seward. Many of the remaining RB streams serve as short run connectors between small peatlands, especially on the bedrock benches above the Snow River. Numerous small first-order streams occupy closely adjacent valleys on the 800' elevation bedrock bench above Fourth of July Creek. The closely adjacent valleys were lumped as single wetland units because they were too small to map separately at the scale used.
