The Botany of Iceland - 01.12.1945, Page 121

THE VEGETATION OF CENTRAL ICELAND
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the plants. A paper by the same author (1902, p. 34) contains a more
complete description of the melur vegetation “as a barren gravel desert
with an extremely scattered and poor vegetation consisting of all the
hardiest fell-field plants, e. g. Silene acaulis, Armeria elongata, Saxi-
fraga oppositifolia, Arabis alpina, and A. petraea and some others,
which at large intervals form small, often abundantly flowering gay
tufts on the dreary greyish gravel flats. Some few half-withered culms
of grasses (Festuca ovina, Poa glauca) are seen here and there, in more
sheltered places they also form small tussocks. On the most barren
gravel flats there occurs in addition a lichen species, Stereocaulon
denudaltum, forming high vaulted greyish cuchions.” (translated from
the Danish). Of the species mentioned here I have never found Arabis
alpina on the typical melur. Stereocaulon occurs in certain places, thus
around Vatnahjallavegur, but is not common throughout the highland.
J ó n s s o n’s descriptions of the melur on Snæfellsnes and in other
places does not differ very much from Stefánsson’s. However,
no author mentions the highland melur as often as Thoroddsen,
who often refers to it in his travel descriptions and in his paper (1914,
p. 305) gives lists of different highland species most of which are
chiefly found on the melur. The same paper (p. 326) contains a list
of the most important species of the lowland melur. M 0 1 h o 1 m
H ansen defines the melur vegetation as follows (1930, p. 179):
“T he melarvegetation is likewise bare of snow in the winter.
The surface is covered with gravel and is dry, with polygonal forma-
tion or solifluction. The vegetation is open, but with a relatively high
number of species and density.” This definition is intended to apply
to both the highland and the lowland melur. As to the alpine melur
it should be added that it is not particularly free from snow in the
winter though in most cases it is more free from snow than most of
the other formations; however, in this connection it should be borne
in mind that the greater part of the highland is covered with snow in
the winter. On account of the configuration of the terrain certain
parts of the melur must have a long-lasting snow-covering, and in such
places the highland melur is often rather damp till late in the summer.
Furthermore, we cannot say that “a relatively high number of species
and density” are found.
As stated above, the melur vegetation investigated by me chiefly
occurs near the oases, and it therefore contains a greater number of
species than the typical highland melur; in addition there occur species
which no doubt belong just as much to other plant communities. The