Greinar (Vísindafélag Íslendinga) - 01.01.1942, Blaðsíða 28

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E ...................... 64.0 55.0 59.0 59.7
Ph ...................... - 0.8 1.0 1.1
Ch ...................... 9.0 15.8 17.0 15.2
H ....................... 56.0 53.0 52.0 52.4
G ....................... 16.0 15.4 15.0 10.6
HH ...................... 6.0 6.7 6.0 9.2
Th ...................... 13.0 8.3 9.0 11.5
This table shows, firstly that the flora of Æðey is much
richer in southern species than the flora of ísafjarðardjúp
and the flora of the country as a whole, as may also be
expected for the island is all lowland, but it shows also
a higher E% than the flora of Isafjarðardjúp 0—100 M.
Then it is also noticeable how the Ch% is lower but the
H%, Th% and G% higher in Æðey than in the other
spectra. It is, therefore, possible to distinguish the flora of
Æðey as especially southern and rich in Hemichrypto-
phytes as compared with the West fjords and, indeed, with
the country as a whole. The causes of this departure in
the biological spectrum are to be found in the climate.
The purely insular climate is very unfavourable to
Chamaephyte vegetation. But probably the influence of
the human habitation is still stronger in exterminating
Ch. It is very noticeable, both in the spectrum and especi-
ally in the aspect of all the vegetation of the island how
much poorer it is in shrubby plants than the mainland on
both sides, where the Chamaephyte associations are domi-
nant over large areas and, at least at the upper end of the
Djúp, the predominating plant associations between the
mountains and the sea. I find it possible to conceive that
the great number of Therophytes, on the other hand, is to
be attributed to the human habitation, as among them are
most of the species of weeds to be found in the gardens
and cultivated meadows of the country, but, on the other
hand, it is likely that the summer is longer here on the is-
land than up on the mainland, or in other words that there
are fewer night-frosts there, so that annuals find it easier
to ripen their seeds here than elsewhere. It would be en-