Rit (Vísindafélag Íslendinga) - 01.06.1975, Side 80

the following species are most conspicuous: Carex rostrata, C. pa-
nicea and C. saxatilis, Calamagrostis neglecta, Agrostis canina,
Festuca rubra, F. vivipara. Comarum palustre is also quite notice-
able. Thalictrum alpinum and Polygonum viviparum were widely
distributed as elsewhere in mýri sociations.
For the purpose of comparison with these analyses from Flói I
have one observation from Kárastaðir in Vatnsnes, where C. nigra
and V. uliginosum were much more conspicuous than Eriophorum.
Other leading species are: Equisetum palustre, E. arvense, Geum
rivale, Pamassia palustris, Salix glauca, S. lanata, Thalictrum
alpinum.
The species of this sociation are numerous. The biological spe-
ctmm is not in the least at variance with mýri sociations in general,
with the exception that the HH percentage is in parts quite high.
39. C. nigra — C. rariflora soeiation
(Tal). IX A-B 1-7)
Observations are at hand from four different parts of the country,
since this sociation is widely distributed throughout Iceland, al-
though is rarely appears in extensive continuous covering. Much
in the manner of preceeding sociations it nurses a close relation-
ship with the flói, and in parts it approximates a transitional form
between flói and mýri vegetation. It distinguishes itself, however,
from C. rariflora sociations of the flói by virtue of its greater num-
ber of species and a different topography, which together with the
abundance of C. nigra determines where it is to be classified.
Apart from the two character species the following may be
mentioned as fairly frequent accompanying species, E. angusti-
folium, Polygonum viviparum, Calamagrostis neglecta, Salix glauca
and S. herhacea. Also worthy of mention are Equisetum palustre,
Euphrasia frigida, Thalictrum alpinum, Vaccinium uliginosum,
Juncus triglumis and Luzula multiflora, and in some parts Carex
dioica is significant. Species are fewer here than in preceeding
sociations.
The biological spectrum indicates a divergence from those above.
The A group is more conspicuous here and attains a clear majority.
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