Rit (Vísindafélag Íslendinga) - 01.08.1930, Side 13

13
a vegetation which, in fact, belongs to different growth-
conditions.
But, as pointed out already, the plant-list niust not be
directly compared with the result of the circling, but the
difference is still so great, that is is easy to see the main
distinction between the vegetation-groups.
A few words might also be said about the swamp (cf.
table I, col. 4). As the table shows, Carex Goodenouhgii and
Equisetum palustre are the chief species here and charac-
terize it. Compared with the forest-land, which is at the same
altitude near the arid land by the river, it is obvious at once
that the A group is greatly dominating in the swamp. G has
also gained a high percentage here, while H has decreased to
the same extent.
The forest reaches nowhere into íhe moisture-land, it is the
same phenomenon as elsewhere in Iceland that the birch-forest
avoids the moisture, and keeps to the dry land around. The
birch possibly avoids the chill of the swampy soil; in our
neighbouring countries, however, it grows mainly in moisture,
but there the climate is warmer than here.
Lastly Tll add a table over the temperature at Stóri-Núpur.
The climatic conditions there will be similar to those of
Ásóifsstaðir, as these two places are within short distance of
each other. The table shows the mean-temperature for 18 years,
for the period 1874—1901: it is quoted from »Lýsing Islands*.
Mean-Temperature at Stóri-Núpur.
The year ]an. Febr. Mar. Apr. May ]une
2,8 —3,0 -2,4 —2,5 1,7 5,6 8,9
]uly Aug. Sept. Oct. Nov. Dec.
10,8 9,3 6,7 2,2 —0,7 —3,1
Winter . . -2,8 Summer ■ 9,7
Spring . . 1,6 Autumn ■ 2,7
EXPLANATIONS.
The Raunkiær Method.
Its object is to get in figures the proportion between the
different plant-species in each formation.
i.