Greinar (Vísindafélag Íslendinga) - 01.01.1935, Blaðsíða 129

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Plant formations.
There is no opportunity here to give a detailed report
of the formations, which are to be found there. But I
consider it proper to give here a very short survey with
a definition of the most important of them, and name
their characteristic species. This must not be regarded as
a description of the formations, and indeed such a de-
scription would need to be accompanied by a much more
detailed report with descriptions and a definition of their
associations. Likewise there would have to be a descrip-
tion of the life-conditions in each formation. I hope that
I shall be afforded an opportunity in the future to do this
work as it needs to be done. The chief formations by Fjalla-
baksvegur are:
1. Sand. Large areas in the desert land there are cover-
ed with sand. It is for the most part without vegeta-
tion and always moving. In certain places however are
to be found tufts of Elymus arenarius and Silene maritima.
Some of the lavafields, e. g. Dómadalshraun are so covered
with sand that from the point of view of vegetation they
may be counted as sand. On the fringes of the sandy
areas, where there is enough moisture, there grow Cala-
magrostis neglecta, Carex incurua, Equisetum aruense and
Cerastium trigynum.
2. Melar (Grauelly flats). Gravelly flats are usually found
up on the ridges of the mountains. The chief character-
istic plants are: Salix herbacea, Cerastium alpinum, Saxi-
fraga oppositifolia, Armeria uulgaris, Arabis pelrœa, Festuca
ouina, Poa alpina and P. glauca.
3. Laua fields. Of these I only surveyed Laugahraun. In
this, especially in the lower part, there is a great deal of
moss with scanty phanerogam vegetation. It is a mixture
of melar-vegetation and mosathembur-vegetation (Grimmia
Heath vegetation). Of plants found there may be men-
tioned Poa laxa, Sagina intermedia and Epilobium lacti-
florum.
4. Mosathembur (Grimmia Heath). They are mostly to