Rit (Vísindafélag Íslendinga) - 01.06.1975, Side 88

this is apparently the most common mire-type but the density of
moss is variable. Analysis 7 is from meadows at Krísuvík. The sur-
face is even, but somewhat sloping. There are springs at the top
of the slope and as a result the ground is rather wet. Moss is copi-
ous. C. nigra and Equisetum have similar covering. I have been
unable to find in Scandinavian studies any sociation comparahle
to this one.
Equisetum palustre-Wiese (Kalela 1939, p. 383) comes closest
to those E. palustre sociations which grow on dry riverbanks or
constitute the horder (jaðar) of flæðimýri.
47. C. nigra — E. palustre — C. Lyngbyei soeiation
(Tab. X A-B 12-16 and Tab. Xx A-B 8-15)
Observations of this sociation are almost exclusively from Rang-
árvallasýsla. It is very common in low-lying parts and often covers
extensive areas. My observations of this sociation elsewhere are
but insignificant; there exist, however, two other observations, from
Snæfellsnes and Borgarfjörður. I cannot, therefore, arrive at any
definite conclusion as to its occurrence or distribution elsewhere in
the country.
This sociation is closely related to the preceding one, no. 46, but
there are some significant differences. As before, C. nigra is domi-
nant, both in physiognomy and covering. E. palustre is also quite
conspicuous although it is less noticeable than in preceding socia-
tions. On the other hand, C. Lyngbyei is among the character spe-
cies here and is a close second to C. nigra. In this respect the so-
ciation is related to the C. Lyngbyei flói or even flæðimýri. This
is supported by the fact that it is sometimes found in mires which
are originally flæðimýri, although they have lost their original
characteristics by virtue of having dried out. Where this sociation
grows the land is grassy with good meadows. Apart from the three
character species, the following are common and some of them
practically constant. As far as frequency is concerned many of them
are among the dominant species, although they are not very notice-
able in physiognomy coverings:
Festuca rubra, Ranunculus acris, Calamagrostis neglecta, Epilo-
bium palustre, Luzula multiflora, Polygonum viviparum, Carda-
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