Rit (Vísindafélag Íslendinga) - 01.06.1975, Blaðsíða 107

finely pattemed and often gently sloping. Analyses 6—7 are from
Fljótsheiði (altitude approximately 350 m above sea level). The
grormd is finely patterned with abundant moss, and as a result
the phanerogamous vegetation is but sparse, the mounds are moss
mounds proper, some Sphagnum occurs. Within the C. Bigelowii
mýri there occur hollows where Eriophornm angustifolium and
Carex dioica are dominant. Analyses 8-9 are from öxnadalur. 9 is
from a mire patch through which a brook flows; the ground is
damper closest to the brook where there is a pure C. Bigelowii — C.
rariflora sociation. Analysis 10 is from Sellandagróf where Betula
nana is very conspicuous. Analysis 11 is from Grafarlönd where
the ground is damper and more mound-pattemed than in the other
localities. Finally 10 is from Kringilsárrani (altitude approxima-
tely 650 m above sea level) where the sociation occurs in small
scattered patches.
60. C. Bigelowii — Festuca rubra sociation
(Tab. XIII 12-13 antl Tab. XIIIx 7-8)
The observations were made in Vestfirðir, on the ridge between
fsafjörður and Langidalur at an altitude of 180-200 m above sea
level, and at Miklumýrar in Gnúpverjaafréttur at an altitude of
approximately 500 m above sea level. Despite these widely differ-
mg environments the sociation is surprisingly homogeneous. In
Vestfirðir Poa alpina is conspicuous and Festuca ruhra is missing
from analysis 12. In my paper (1946 p. 11) I have called this a
C. Bigelowii —- Graminé rich sociation. Apart from the character
species Festuca vivipara and Poa alpina are sometimes conspicu-
ous. Equisetum arvense and Salix herhacea are also extensive, hut
msignificant in physiognomy. Among common species belonging
to other sociations of the C. Bigelowii mire the following are most
tmportant: Polygonum viviparum, Eriophonnn angustifolium, Tha-
lictrum alpinum and Calamagrostis neglecta hut they are all pro-
strate with the exception of Polygonum. The biological spectnnn
is notable with regard to the low Ch percentage and the G percen-
tage which is considerably below the H percentage.
The sociation is widely distributed in Isafjarðardjúp and it is
also ahundant at Miklmnýrar where it grows on ridges scattered
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