Greinar (Vísindafélag Íslendinga) - 01.01.1967, Blaðsíða 40

38
topography of the islands is relatively stable the vegetation has
reached the stability of climax communities. In contrast with this,
pioneer plants have just started colonizing the coast of the recent
island of Surtsey. It is hoped that future studies of its vegetation
will reveal the means of dispersal and evolution of seral communi-
ties of the Westman Islands.
Introduction
Colonization of terrestrial plants on the new volcanic
island Surtsey in the Westman Islands group is affected
by the available source of species on the adjacent land
masses as well as means of dispersal and environment
conditions on Surtsey.
As a background for evaluating the colonization of
plants on the new island a good knowledge of the flora
of these land masses is necessary. In the manual of vas-
cular plants of Iceland (Stefánsson 1924 and Löve 1945)
records are made of some species of vascular plants grow-
ing in the Westman Islands as well as the various loca-
tions on the adjacent mainland. A thorough study of
higher plant life on Heimaey, the only inhabited island
of the Westman Islands group, was carried out by Baldur
Johnsen (1939) who also made some studies on Bjarnar-
ey. A few additional observations have been made on the
vegetation of the outer islands, although no floral lists
were available. In order to establish better knowledge of
the flora in this area, it was thus considered necessary
to carry out an investigation of the vegetation of the
outer islands. The work was sponsored by the Surtsey
Research Society with a grant from the United States
Atomic Energy Commission.
Topographical Features
According to present knowledge, geologists believe the
Westman Islands to have been created by volcanic activi-
ties towards the end of and after the last Glaciation. The
formation of Surtsey has clarified facts concerning the