Rit (Vísindafélag Íslendinga) - 01.06.1975, Blaðsíða 116

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and C. chordorrhiza is so conspicuous as to dominate together with
the character species.
Analyses XIVx. 10-11 from Staðarhraun at Mýrar are unique
with respect to C. nigra which is dominant here and closely ap-
proximates the frequency of the character species. C. rostrata is
also substantial in distribution. The ground is damp here, similar
to analysis XIV. 15 as described earlier.
65. S. cæspitosus — E. angustifolium — Vaccinium uliginosum
sociation (Tab. XIV A-B 3-9)
This sociation is closely akin to sociation 61, but V. uliginosum
is a distinguishing characteristic. It becomes dominant in frequency
here and noticeable in covering, although the other character spe-
cies are more widely distributed, both in covering and physiog-
nomy. The observations are all from the western part of the coun-
try, extending from Borgarfjörður to Vestfirðir. The sociation occurs
in relatively dry mires, mound formation is scanty and the mounds
are so low that there is nowhere any difference in vegetation be-
tween mounds and depressions. In many places the surface is com-
pletely flat. The slope is gentle and the conditions often resemble
Eriophorum flói. Some Sphagnum occurs in many places; it is
most abundant in analysis 7, where it covers up to 10% of the
surface. Apart from the character species no single species is con-
spicuous in all the analysis. Empetrum hermafroditum is fairly
frequent in some of them, mostly in 5. The common species of the
Scirpus mire, Polygonum viviparum and Thahctnnn alpinum are
widely distributed. C. Bigelowii has a high frequency rate in some
of the analyses and similarly C. dioica and C. nigra. The number
of species is relatively small. In analyses 8-9 V. uliginosum be-
comes much less frequent as indicated by the low Ch percentage in
the biological spectrum, but the Ch percentage is otherwise high. In
analyses 7—9 the H percentage becomes higher than the G percen-
tage. This is a common sociation on Snæfellsnes where analyses 3—6
were made. Analysis 7 is from Skálavík in Norður-Isafjarðarsýsla
where the sociation is uncommon. Analyses 8-9 are from Hvann-
eyri in Borgarfjörður where the sociation seems to be rare. It may
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