Study of the Alaska Tundra with Reference to its Reactions to Reindeer and other Grazing Page: 27
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STUDY OF THE ALASKA TUNDRA
The vegetation is dominated by the sedges, with lichens (Ca-
donia and Nephroma) present in smaller quantities. The browse
species are Ledum, prostrate willows, ground birch, Empetrum,
and cranberry.
Study of this type was begun in 1927, when an exclosure was
erected about a mile south of the native village at Cape Etolin
on Nunivak Island. The site chosen was nearly level and at
about 70 feet elevation. Three 1-meter-square quadrats were
established within the exclosure for the purpose of determining
the effect of grazing, denudation, and trampling on the sedge-
lichen vegetation (fig. 10).
Cut quadrat.-The first of these quadrats had a full cover of
vegetation estimated to be composed of 45 percent sedges, 32
percent lichens, 12 percent browse species, and 11 percent mosses.
This was removed by cutting it at the ground surface with a
sharp knife.
A full cover of vegetation was reestablished the third year
after the cutting, with Eriophorum making up 75 percent of the
stand. Mosses were estimated to compose 15 percent and lichens
the remaining 10 percent of the growth. Nine years after cut-
ting the vegetative cover consisted principally of sedges, Carex
forming 40 percent and Eriophorum 60 percent. A vigorous
growth of sphagnum moss was found underneath the accumula-
tion of dead sedge leaves.
Spaded quadrat.-The second quadrat was similar to the first,
having a complete cover of vegetation made up of 45 percent
sedges, 31 percent lichens, 12 percent browse species, and 12
percent mosses. The plants, including their roots, were removed
by spading. Revegetation occurred rather slowly, a complete
cover not being established after a lapse of 9 years. Eriophorum
was the principal invader, followed by Carex, Sphagnum, and
willow. When the quadrat was last examined, in 1936, the den-
sity of the vegetative cover was estimated to be 0.95. Erio-
phorum composed 40 percent of the stand, Carex 35 percent,
sphagnum mosses 20 percent, and willows 5 percent. The wil-
lows apparently crept in by layering from plants in the check
quadrat.
Check quadrat.-This undisturbed quadrat had a complete
cover of vegetation made up of 50 percent sedges, 30 percent
lichens, 15 percent browse species, and 5 percent mosses. Dur-
ing the period of observation some changes occurred in the vege-
tative cover. A gradual decrease in lichens and a corresponding
increase in sedges and willows were recorded. At the end of 9
years the cover was complete and was made up of 70 percent
sedges (Carex and Eriophorum in about equal quantities), 22
percent browse, mostly willow, and 8 percent lichens and mosses.
Many runways of lemmings were found underneath the ac-
cumulation of dead sedge leaves. It is possible that these ro-
dents caused some of the change in vegetation, but observations
on this point have not been sufficient to be conclusive.
Summary.-The length of time required for vegetation in the
wet tundra type to recover after disturbance seems to be directly
proportional to the degree of disturbance. Eriophorum callithrix27
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Palmer, Lawrence J. & Rouse, Charles H. Study of the Alaska Tundra with Reference to its Reactions to Reindeer and other Grazing, report, 1945; Washington D.C.. (https://digital.library.unt.edu/ark:/67531/metadc100536/m1/32/: accessed July 17, 2024), University of North Texas Libraries, UNT Digital Library, https://digital.library.unt.edu; crediting UNT Libraries Government Documents Department.