Rit (Vísindafélag Íslendinga) - 01.06.1975, Page 83

42. C. nigra — C. cliordorrhiza sociation
(Tab. IX A-B 9, 16)
There are only two observations available here, i.e. from Skaga-
strönd and Rauðholt in Fljótsdalshérað in rather wet and slightly
sloping areas. The sociation is related to the C. chordorrhiza flói. The
two character species are about equal in covering, but C. nigra is
dominant in physiognomy. As far as I know, this sociation is rather
fare, and nowhere it covers big areas.
43. C. nigra — C. rostrata — Equisetum sociation
(Tah. XIx A-B 2)
The only ohservation is from Ketilsstaðir in Jökulsárhlíð, in a
relatively dry, sloping mire. The character species are fairly even-
ly distributed in the physiognomy, but C. nigra is clearly most pre-
valent. Despite a high Ch percentage the shrub growth is rather
mconspicuous, being low and prostrate. The extent of distribution
is unknown.
44. C. nigra — Caltha palustris sociation
(Tab. XIx A-B 3-4)
I have only come across this sociation in the Eyjafjöll area on
smooth, level ground to the southwest of Drangshlíð. When exa-
mined the land was practically dry, but there were unmistakable
traces of spring floods. As far as could be determined this is a
fertile moraine and the soil is obviously shallow. In low-lying areas
where the ground is dampest E. angustifolium appears — this was
m fact the kind of terrain where analysis 4 was carried out — but
otherwise C. nigra is completely dominant in this area. In analysis
3 Trifolium repens is prevalent and in both the analyses Poa pra-
tensis occurs quite frequently. These species indicate that the so-
ciation is akin to flói (level mire) or rather, the borderland of
flæðimýri (alluvial mire) and they also show some indications of
alluvial land. It is worth mentioning that there are meadows in
the area. It is difficult to determine the extent of the sociation’s
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