Rit (Vísindafélag Íslendinga) - 01.06.1975, Síða 89

mine pratensis, Anthoxanthum odoratum, Caltha palustris, Trifo-
lium repens, Comarum palustre, Juncus balticus and Carex rari-
flora. The herbaceous plants are often so conspicuous as to charac-
terise individual patches in marked contrast with the monotonous
verdure of the mire.
There are numerous species, similar to 46, but their level of
density is not as high. The biological spectrum is surprisingly
monotonous, despite some fluctuations, but it should he horne in
mind that most of the observations are from the same region. The
E group is prevalent everywhere which indicates that the condi-
tions are favourable for the more southernly species. In many
places H are the dominant lifeforms, although the two character
species are Geophytes. There is quite a high HH percentage in
many places, but Th is almost totally lacking.
This sociation usually occurs in rather wet mires. The slope is
variable, but usually rather gentle, sometimes little more than may
occur in flói. Peat formation is everywhere insignificant, and some-
times nonexistent in places where the soil is sandy, partly because
of river deposits and partly due to volcanic ash. The knoll-pattem
also varies, in places the knolls are low and flat, but rather coarse
elsewhere; nowhere is there any marked difference in vegetation
between knolls and depressions.
Analysis X. 12 is from Kirkjulækur in Fljótshlíð. This sociation
is common in damp areas towards the foot of mountain slopes where
the ground is relatively flat, but sociation 46 is more commonly
found in drier more sloping areas. Gramineous plants do not occur
with any frequency. Although the knolls are rather small here it
is noticeable that E. palustre tends to cover the knoll-tops, whereas
C. Lyngbyei appears in the depressions.
Analysis X. 13 is from Skáli in the Eyjafjöll district. There the
land is practically level; it is in fact an old alluvial formation
which is still flooded from time to time when the rivers are swollen.
There the sociation covers extensive areas which are rent by low,
knolly strips, covered with Juncus balticus, E. palustre and grami-
neous species or other vegetation characteristic of the border of
flæðimýri.
Analyses X. 14—15 are both made within a small area on the
Bergþórshvoll meadows. There is also an old delta formation in
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