Rit (Vísindafélag Íslendinga) - 01.06.1975, Blaðsíða 42

7. E. angustifolium — C. rariflora — C. chordorrhiza sociation
(Tah. III A-B 1-5)
The available observations are from Kaldidalur, Snæfellsnes, and
Hagi at Barðaströnd. The sociation is quite related to the preceed-
ing sociation no. 6, with the exception, however, that C. chor-
dorrhiza is here added as a character species, and it has the most
extensive covering of all three character species. Constant accom-
panying species are hardly worth mentioning, since the sociation
is poor in species. Menyanthes trifoliata, Carex limosa and C.
panicea, however, are conspicuous in lowland analyses. The A per-
centage is relatively high and geophytes are dominant.
Analyses 1-2 are from Kaldidalur at an altitude of 400-500
metres above sea level, taken from a level, wet flói, which in no
way seems to distinguish itself from the E. angustifolium — C.
rariflora sociation. Analysis no. 3 is from Hagi in Barðaströnd, the
sociation is intertwined with sociation no. 9 Tab. IIIxl in such a
fashion that broad, low, undular formations covered with sociation
9 alternate with hollows where sociation 7 becomes predominant.
In the deepest hollows a pure C. chordorrhiza sociation emerges.
It seems quite clear here how decisive the depth down to the level
of the ground water is. Analysis 4 is from Hausthús in Snæfellsnes
in a very wet flói with straggly Scirpus mounds, not unlike the
undular formations in the flói at Hagi. The flói is here dissected
by mound ridges, which are not high enough, however, to deserve
the name ridges proper, and they are mostly parallel. Sometimes
they reach a length of 20 metres, 0.5—1.0 m. in width, and 20—30
cm. in height. On these ridges the character species disappear ex-
cept for E. angustifolium. These character species are replaced,
however, by Carex nigra, Scirpus cæspitosus, the shrubs Betula
nana and Vaccinium uliginosum together with some dry ground
species. Analysis 5 is from Staðastaður, taken in a wet flói tract.
Here the species are more numerous than on the other location
and C. chordorrhiza is most abundant of the character species.
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