Rit (Vísindafélag Íslendinga) - 01.06.1975, Side 48

since they often adjoin a Scirpus sociation. The number of species
varies and it depends on the moisture content of the flói. E. group
is in significant majority, but H and G percentages are similar.
Where this sociation occurs the flói is rather wet, and the surface
is slightly mound pattemed. The shmb plants then collect mostly
on the mounds although these are low.
Analysis 1 is from Orrastaðir in Húnavatnssýsla, which is among
the drier and more level parts, and the shruhs are evenly distributed
throughout the area. The sociation is widely distributed there over
the ridges. Analysis 2 is from Skjaldfannardalur, where it is wetter
and the mounds are more pronounced. On the other 3 locations
the topography is similar, still at Laugarholt, analysis 3, the so-
ciation grows exclusively on low mound ridges, whereas on the
level ground between them the shrubs disappear and Carex saxa-
tilis and C. chordorrhiza become noticeable. Sphagnum occurs in
all those analyses.
14. — 15. E. angustifolium — Carex Lyngbyei sociation
(Tab. IV A-B 6-7)
E. angustifolium C. Lyngbyei — C. nigra soeiation
(Tab. IV A-B 8)
These sociations, which are actually so interrelated that it is a
doubtful proposition to set them apart, occrn- in many places in the
country in flói tracts, but only in small patches and preferably
where the flói resemhles a flæðimýri. In analyses 6—7, which are
from Kjölur and Kaldidalur, the character species are alike in do-
minance, although E. angustifolium is more noticeable in physiog-
nomy.
Analysis 6 is from Hvítárnes. Apart from the character species
there are Salix glauca, Eriophorum Scheuchzeri, Carex rariflora
and Equisetum variegatum, which are noticeable. But these species,
in particular the two first mentioned, indicate an incipient pioneer-
ing stage of flæðimýri. In fact this sociation occurs at Hvítárnes
onlv in the vicinity of shallow ponds, which often are surrounded
by Carex rostrata, where the pond bottom is covered by Amblys-
tegium. The soil is sandy, the surface finely mound patterned and
48