The Botany of Iceland - 01.12.1945, Síða 82

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STEINDÖR STEINDÓRSSON
5. Taraxacum—Calamagrostis neglecta-Ass. (Tab. X. A-B, 4).
In regard to the biological spectra this association is closely related
to the preceding one, but differs from it in species composition and
physiognomy in that Ranunculus acer has disappeared and Calama-
groMis neglecta is present in such great numbers that it must be re-
garded as one of the dominants. Rumex Acetosa is likewise very con-
spicuous. The association is not so rich in species as the preceding one.
The analysis was made at Sáta on Landmannaafrjettur, the exposure
is northeasterly, the soil damp, and the snow-covering probably
moderate. The association occurs here and there on Landmannaafrjet-
tur, but was not observed in other places.
6. Alchemilla minor—Sibbaldia procumbens-Ass.
(Tab. X. A-B, 5. XII. A-B, 1).
Alchemilla minor is dominant in this and the following association.
Both these associations are a kind of variants of the almost pure Al-
chemilla minor patches with a damp soil and a thick, but not too long-
lasting, snow-covering. Sibbaldia procumbens dominates physiognomical-
ly in company with Alchemilla. Other dominant species are Carex
rigida, Thalictrum alpinum, Phleum alpinum, Poa prcttensis, and
furthermore Anthoxanthum odoratum and Agrostis canina are of im-
portance. Analysis X, 5 was made at Sáta on Landmannaafrjettur,
c. 700 m above sea-level; the locality has an eastward exposure, and
a thick snow-covering. Analysis XII, 1 is from Síðumannaafrjettur,
c. 400 m above the sea, but was made in a deep depression. The as-
sociation is found here and there in all the areas investigated except
on Brúaröræfi, whence it is not noted down.
7. Alchemilla minor—Salix glauca—Anthoxanthum-Ass.
(Tab. X. A-B, 6-7).
As in the preceding association, Alch. minor dominates physiognom-
ically, but in company with Salix glduca and Anthoxanthum, whereas
Sibbaldia has nearly disappeared. Otherwise they have most dominants
in common, with the exception of Carex rigida, Phleum alpinum, and
Agrostis canina, all of which have been much reduced in number; of
the Gramineae, Festuca rubra is most conspicuous. Both associations
6 and 7 show good agreement in regard to the biological spectra, the