The Botany of Iceland - 01.12.1930, Page 55
STUDIES ON THE VEGETATION OF ICELAND
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Table 10 b. Biological Spectra of the Melar Vegetation.
1 2 3 4 5 6 7
Points sum 412 i «92 580 320 220 688 940
Number of species 14 20 22 15 13 14 29
Densitv of species 4.1 (i.9 5.8 32 2.2 6.9 9.4
A 62.1 56.6 75.2 72.5 50.9 52.9 54.5
E . .. . 37.9 43.4 24.8 27.5 49.1 47.1 45.5
A 3 40.8 32.9 52.4 50.0 23.6 27.3 28.5
A 2 19.4 19.7 19.3 15.0 12.7 25.6 17.4
A 1 1.9 ; 4.0 3.4 7.5 14.5 » 8.5
E 4 23.3 33.5 22.1 25.0 34.5 37.2 29.8
14.6 i 9.8 2 8 2.5 14.5 9.9 12.8
E 2 > ! » > » » 2.1
E 1 » i » » > » > 0.9
Ch 28.2 45.1 42.8 37.5 45.5 55.2 47.3
H 53.4 42.2 45.5 43.8 54.5 33.1 44.6
(i 18.5 ! 12.7 11.7 18.8 > 11.6 8.1
HH > | > » > > > »
Th 1 1 > > > > > >
ences in the vegetation, but owing to the small part played by the
vegetation in tlie appearance of the landscape it is difficult to fonn
an idea as to how much this is the case. It is easiest to ascertain
the connection between the vegetation and the age of the area as
melar soil. On recently denuded patches hardly any plants are seen,
whereas a good deal are seen to have immigrated at a somewliat
later stage. Fig. 5 shows such a melar vegetation near Hrólfsliólar,
and table 10 A 1 and 4—5 give the circling results for tliis and
similar localities on Lýngdalsheiði. The density of species is still
rather low, 2 —4, in spite of the comparatively liigh number ot spe-
cies, c. 15. Of life forms H and Ch are almost the sole prevailing
ones. The most conspicuous species are Thynuis serpyllum, Salix
herbacea, Armeria, Silene acaulis, Cerastium alpinum, and Arabis
pelrœa-, of herbaceous planls Juncus trifidus, Luzula spicata, Polij-
gonum viviparnm, Agrostis canina, Festuca ovina, and F. rubra are
met with.
On still older stretches of melar not only the vegetation bul
also the character of the soil have undergone change. The soil