Náttúrufræðingurinn - 1965, Side 8

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NÁTTÚRUFRÆÐINGURINN
Friðriksson, Sturla (1965): Biological records on Surtsey, Tlie Surtsey Biology
Conlerence, Proceedings l)ls. 22—24. (Fjölrit).
Löve, Ashell og Doris (1947): Studies on the origin ol the Icelandic Ilora, Rit
Landbúnaðardeildar B-flokkur nr. 2, bls. 29.
Löve, Áskell og Doris (1956): Cytotaxonomical conspectus of the Icelandic
Flora. Acta Horti Gotoburgensis 20 bls. 176—178.
Martin, C. H. (1857): Expérience sur la persistence de la vitalité des graines
flottant a la surface de la mer, Bull. Soc. Bot. France, IV bls. 324—337.
Ridley, H. N. (1930): The dispersal of plants throughout the World. — Ashford.
Thoroddsen, Þorvaldur (1931): Lýsing íslands I., bls. 42—43.
SUMMARY
The first species of higher plants in Surtsey
the new volcanic island
by Sturla Friðriksson
University Researcli Institute, Department oj Agriculture.
The first species of higher plants to colonize the new volcanic island of
Surtsey off thc coast of Iceland was discovered June 3rd 1965. Three small
seedlings of Cakile edentula were found growing upon the sandy beach north
of the small lagoon on the island. A few days later an expedition discovered
some 20 additional seedlings growing at a more eastern location on the same
shore.
The plants had grown from seed that apparently had been washed upon.
the sand by the sea. 'Lhey, however, did not mature but were a few
weeks later killed by and l>uried under a shower of ashes carried lrom the still
younger volcanic island of Syrtlingur. The fall of fresli tephra from the satel-
lite volcano has thus temporarily delayed the colonization of higher plants on
the main island, Surtsey.
The inciclent, however, does show that living Cakile seed are being dispersecl
over such distances as between Surtsey and some Cakile colony, the nearest
being on an island 20 knt away. A test of the viability ol Cakile seed after
immersion in sea water furthermore supports the possibility of dispersal of
such living seed over still greater distances.
Seeds of Cakile as well as seecl of five othcr conunon Icelandic species were
stored in salt water at 2°C for several months.
Seeds of all these species were founcl lo withstand four months of ol immer-
sion in sea water. And all but onc survived up to eight months of innuersion
without a major decrease in germination ability (see table).
This indicates the possibility for such seed to keep their viability in the cool
waters ol the North-Atlaniic for several rnonths. A sufficient time to allow
them to be dispersed long distances in salt water.