Rit (Vísindafélag Íslendinga) - 01.06.1975, Page 152
Agrostis canina and Festuca rubra become dominant in frequency.
Moss is abundant and covers 20-30% in many places. The sur-
face is characterised by low, flat mormds. There is unmistakable
affinity to the Kobresia heath, but the occurrence of Juncus balticus
separates the sociations. It could be a moot point, however, whether
this sociation should not be referred to as a variant of Kobresia
heath.
88. J. balticus — Salix glauca sociation
(Tab. XX 11)
This sociation occurs principally in highland regions and I have
described it more fully in my paper 1945 (pp. 405 and 509—510)
where it is said to occur mainly on river banks, in which case it is
a transitional form to Salix heath. In lowland areas it is probably
rare, but the only analysis at hand is derived from the lowland in
the estuary tracts of Jökulsá í Dal near Ketilsstaðir in Jökulsárhlíð.
There is a flæðimýri adjacent to the sociation, although a Juncus
balticus jaðar is hardly ever connected with such a formation. The
biological spectrum shows a very high A percentage and the result
appears to be similar both in lowland and highland regions. The
Ch percentage is high as is to be expected since one of the character
species is Ch.
89. J. balticus — Deschampsia alpina sociation
This sociation occurs exclusively in the highland, but is, how-
ever, rare. I have presented one analysis in my paper 1945. I have
not observed this sociation elsewhere and do not propose to discuss
it any further. It seems closely related to the Calamagrostis neg-
lecta sociations.
90. J. balticus — Carex Bigelowii — Empetrum sociation
(Tab. XXI A-B 2)
Only one analysis was made here, in the same parts as analysis
Tab. XX. 11, sociation 88. These sociations are closely related, but
here Empetrum replaces S. glauca as a dominant. The species are
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