Rit (Vísindafélag Íslendinga) - 01.06.1975, Side 31

As far as I can determine there is a close relationship between
the Eriophorum flói and Svartmyrarnas forbunn in Norway (Nord-
hagen 1943 p. 519).
I have divided the Eriophorum flói into several sociations on the
basis of their prime species. This is, to be sure, rather difficult be-
cause of the instability of the water level. As may be gleaned from
the tables the analyses count in each sociation is quite variable,
which results largely from the fact that some of my research con-
sists of a meticulous observation of a c.omparatively small area
(Flói, Slétta), hut other surveys were made on field trips of rather
limited duration. It must also be borne in mind that the sociations
are of quite variable distribution and covering. Since the analysis
count is so changeable, it is difficult to compare individual socia-
bons on the basis of the tables alone, but on the other hand I beheve
that they provide a reasonably accurate account of the species com-
position in the sociations treated, because where the analyses are
iewest I strove to select the most typical patches as subjects for
observation. It must be remembered, however, that there is, as
mentioned above, an element of risk involved when you emplov
ihe Raunkjær method, since some species may be omitted, and
tíiese very species might be those which distinguish between socia-
tions. This risk is less in Iceland, however, than in most other
places, because of the paucity of species in general and also be-
cause they are normally densely grouped, so that almost all im-
portant species of the vegetation may be found in small areas.
Little need be said about the acidity of the Eriophoum flói beyond
what has already been stated about mire vegetation as a whole,
hecause no specific observations are available. It may nevertheless
he concluded that the flói and primarily the Eriophorum flói most
closely approximates oligotrophy of Icelandic mires. I here include
a survey by Nordhagen about the acidiphilous nature of Eriophorum
Lói character species and their value in estimating acidity:
Eriophorum angustifolium: indifferent
Carex saxatilis: eutrophic but with wide amplitude
Carex rariflora: indifferent
Carex chordorrhiza: indifferent
Carex nigra: eutroph-mesotrophic
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