File:Ecological investigations of the tundra biome in the Prudhoe Bay region, Alaska (1975) (21117417926).jpg

Title: Ecological investigations of the tundra biome in the Prudhoe Bay region, Alaska
Identifier: ecologicalinvest00brow (find matches)
Year: 1975 (1970s)
Authors: Brown, Jerry, 1936-
Subjects: Tundra ecology
Publisher: (Fairbanks : University of Alaska)
Contributing Library: MBLWHOI Library
Digitizing Sponsor: Internet Archive

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Type3 vegetation of Carex aquatilis, Eriophorum angustifolium, Dryas integrifoliaa^7o'sei/era/ Salix species. The following dichotomous key, which is based on plant rather "than geomorphic or habitat parameters, illustrates the simplicity of the identification process: Key to the most common vegetation types of the Prudhoe Bay area 1. Lichens abundant ^⢠Lichens rare â¢'â 2. Many fruticose and crust lichens . . Type 1 Mostly fruticose lichens Type 2 3. Dryas and/or Salix spp. abundant . . Type 3 Dryas and/or Salix spp. rare ^ 4. Mosses rare Type 6 Mosses abundant ^⢠5. Drepanocladus species dominant . . Type 4 Scorpidium dominant Type 5 We plan to develop a key to all vegetation types. Other functional keys using a variety of para- meters could be made, but we want to avoid mixing descriptors to reduce the problem of circular reasoning when maps are subsequently analyzed and used. Nevertheless, vegetation, habitat, and geomorphology are intimately inter- related, and it is difficult to map them separate- ly at this scale (1:3,000) because of the fine mosaic and patterning of this tundra. But we believe our method will allow a separate analy- sis. We have set up and sampled a number of permanent vegetation plots in both disturbed and undisturbed areas. These plots will serve as baselines for any subsequent changes. We have also set up specimen plots of each vegetation type which can serve as training and reference samples for other potential vegetation users or mappers; these will also serve as permanent baseline plots. Mapping Method The maps were initially constructed in the laboratory using July 1972 CRREL, 1:3,000, black-and-white, air photographs on which major landscape units were then outlined. These units were identified on the basis of uniform tone, texture, and pattern. Each of these units was visited in the field, their boundaries checked and changed as necessary, and their vegetation and geomorphologic features described. The inti- mate interrelatedness of geomorphic and plant patterns makes it difficult to produce separate vegetation and geomorphic maps. Our map (Plate I), however, shows the prevalent or most abundant vegetation type for each landscape unit and also records the geomorphic features and other frequent vegetation types which occur within a unit. The vegetation and geomorphic record is given by a formula of letters and numbers. The numbers in the formula indicate the vegetation types. On polygonal ground the vegetation types are listed in 2 or 3 groups of microsites separated by semicolons (;). The first group is the vegetation on the polygon centers; the second, vegetation on the rims, and the third, vegetation in the polygon troughs. A dash indicates the absence of a group or microsite category. The letter for the most abundant vegetation type is underlined. The letters preced- ing the numbers in the formula indicate the geomorphic features of each map unit: P â polygonal ground; F â flat or gently sloping terrain where ice-wedges are masked or ill- defined; R â small ridges and hills; S â streams and stream margins; W â dunes; L â lakes and ponds, and H â pingos. Often a subscript is used to further define the geomorphic feature: F â flat polygons; L â low centered polygons; H â high centered polygons; M â mixed polygons; B â river bluffs; f â frost boils; s â sandy soil; t â thermokarst pits; and r â reticulate-ridged flats.

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