Náttúrufræðingurinn - 1971, Blaðsíða 54

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NÁTTÚRUFRÆÐINGURINN
Part II deals with the oceanic type of distrihution, i.e. species with a
distinct tendency íor growing in the coastal areas of the South, Southeast and
tlie West of Iceland. The distribution is shown on tlie maps in Figs. 2—15.
Further information accompanies the figures.
About 80 species of the Icelandic flora seem to have a tendency for oceanic
distribution. This number may in reality well be higher, as information is
lacking for most of the more contmon plants.
In part I about 30 species were found to have a continental tendency in
distribution. The numlter of such species with eitlier continental or oceanic
distribution may thus be estimated about 110 species or ]/4 of tite native Ice-
landic flora.
Many of the plants in question do not occupy their whole ]>otential climatic
area. It is suggested that some of them may be relicts from older floras, of
either interglacial, glacial or postglacial age.
An outstanding element of boreal íorest plants in some ot the groups is
really indicating remnants of a post-glacial warm-period-flora, a period when
Iceland was more tlian half-covered with birch woocl. Some of these plants
may be founcl in forests and in mountains far inland in Europe. It may be
concluded that a good deal of the plants with climatic distribution in Iceland
may not necessarily be of climatic nature. Some of the species in groups 1
and 3 may liave been brought to Iceland by the action of man.
Obviously much more work must be done in the mapping of the distribu-
tion of plants in Iceland, before the problem of climatic distribution can be
solved.