Rit (Vísindafélag Íslendinga) - 01.06.1975, Page 52

anthes trifoliata are less significant than in sociation 16, and E.
angustifolium has almost disappeared. The smallest number of
species is in the C. Lyngbyei flói. A group has vanished, H percen-
tage is higher than in sociation 16, but G and HH percentages are
variable. Nothing is to he expressed about biological conditions
heyond what is set forth about the C. Lyngbyei flói in general and
what emerges in notes on individual analyses. Analyses 3 and 5
are from Miklavatnsmýri in Flói, where C. Lyngbyei patches al-
ternate with mound pattemed ridges of mire sociations. These
patches are all level and many contain shallow ponds. As far as
we are able to determine the patches were formed, when small
streams, even mere spring thaw brooks, which flow from the ter-
races above, filled up fhe ponds. The ponds themselves are covered
with Equisetmn fluviatile and Scirpus palustris. There is some hog
iron present. Analyses 4 and 6 are taken from parallel areas at
Breiðamýri in Flói. Analysis no. 6 is made close to a pond, where
the flói surface is about level with that of the pond, but analysis
4 lies a little higher and therefore on drier terrain, which is best
indicated by the fact that the frequency of C. nigra increases.
Adjacent sociations are C. nigra mýri. Analysis no. 7 is from Berg-
þórshvoll in Landeyjar, where the sociation grows in small patches
amid C. nigra mýri. Bog iron occurs in vast quantity.
18. C. Lvngbyei — C. rariflora sociation
(Tab. V A-B 8)
The only analysis presented here is from Hvítámes. No asser-
tion as to its distribution will be made here, but my paper on Mel-
rakkaslétta 1936 contains another analysis. However, I believe that
it is rather scarce and occurs particularly in highland flói areas,
or in those parts of the country where vegetation covering is
similar to that of Melrakkaslétta. The species are very few. Where
the analysis was made this sociation occurred in small patches in
a rather extensive C. Lyngbyei — Calamagrostis neglecta flói. These
were the wettest areas where it grew. The phanerogamous vegeta-
tion was sparse there, but moss abounded (Amblystegia). The so-
ciation is related to sociations 19 and 20.
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