HEADWATER FEN ECOSYSTEM Wetlands
Headwater Fen Ecosystem wetlands are small peatlands occupying the headwaters of first-order streams. They often support diverse plant communities, but a large Headwater Fen on Baldy Ridge had extensive, nearly monospecific areas of Bigelow's sedge (Carex bigelowii). That may be related to the evidence of heavy ATV or snow machine traffic there.
Headwater fens may be particularly important in stream energy cycles. Carbon export from them is important to organisms at the core of the stream's food web. Insects obtain part of their food from carbon processed by micro-organisms. Larger organisms feed on the insects, and the initial carbon source eventually supports larger organisms, such as anadromous fish.
Plant Prevalence Index calculated based on Alaska indicator status downloaded from the USDA PLANTS database, which may use different values than the 1988 list.
Headwater Fen Ecosystem Wetland Map Components:
H2: Headwater Fens with water table near the surface most of the growing season. Often dominated by sedges.
H3: Headwater Fens with fluctuating water table, often dominated by shrubs.
H4: Headwater fens with deeper, fluctuating water table, forested.
Map Units currently in use: H1, H1-3, H12, H13, H2, H2-4, H21, H23, H3, H31, H32, H34, D4, H42, H43