Rit (Vísindafélag Íslendinga) - 01.06.1975, Qupperneq 139

Caltha palustris sociation, and their environment is descrihed under
that heading. Analyses 3-4 are from Mýrdalur, in close cohesion
with an Equisetum palustre — Trifohum repens sociation which
has been described before. Analysis 5 is made in the westem part
of Staðarsveit in Snæfellsnes where fairly extensive C. Lynghyei
mires occur which have formed off the Búðir estuary. Analyses
6-8 are from Flói. They are from a similar environment, that is,
where a C. Lyngbyei sociation has formed at the mouths of irriga-
tion canals which have transported sand, clay and other minerals
into the flói tracts. The vegetation is dominated by C. Lynghyei
where the deposits have collected as bottom sediment, but never-
theless there still remain various mýri and flói species.
The biological spectrum is distinguished from 78 by a consider-
able A percentage, but in 78 A was for the most part absent.
80. C. Lyngbyei — Carex canescens sociation
There is only one analysis available of this sociation, from Skipa-
lón in Hörgárdalur. A strip of this sociation occurs along a river
bank on the fringes of a pond which is grown with Equisetum
fluviatile and sparse Scirpus palustris. C. Lyngbyei is dominant,
both in physiognomy and covering, but C. canescens is fairly
prominent and has considerable covering. Apart from the character
species the following occurred: Carex nigra, C. rariflora, Equisetum
fluviatile and Eriophorum angustifolium. The distribution of this
sociation is unknown.
Pioneer sociations of the flæðimýri
Newly vegetated patches encountered on the banks of streams,
rivers and lakes must also be included in a description of the flæði-
^oýri. Eriophorum Scheuchzeri is generally the main species so
tiiat these patches could well be referred to as Eriophorétum Scheu-
chzeri. This vegetation type invariable originates in the same way;
t-e. in moist sand with continuous water seepage. Although this
Eriophorétum is mainly formed in fluvial sand the sociation may
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