The possibility to follow up the succession of microbial life in
a virgin soil quite free
from organic substances has been fascination. In 1972, five years
after the eruptions
ended on Surtsey, soil samples could still be gathered which did
not show any
evidence of microbial life.
It was not unexpected that free-living blue-green algae with the
ability to use sun energy and
the molecular nitrogen of the air for growth and development, were
among the primary
immigrants of Surtsey. The algae, which nowadays (1982) frequently
occur on the island,
are also found to live in associations with mosses.
is a necessary condition for nitrogen fixation.
The first evidence of biological nitrogen fixation on Surtsey was
recorded in 1970, when it was found in laboratory experiments that
microorgnisms in Surtsey soils showed the activity of nitrogenase,
the enzyme which is necessary for all biological nitrogen fixation.
The organismsms involved were found to be light-depended. By cultivation
it was found
that the nitrogenase activity was derived from the blue-green algae
It may be surprising that algal nitrogen fixation at a high level
can be recorded in soils where
blue-green are not visitble to the naked eye. Therefore, it must
be incorrect when earlier
research stated that blue-green algae are unimportant as primary
colonisers of Surtsey,
since one could not detect them...
necessary condition for nitrogen fixation (nitrogenase activity)
is moisture. Vast areas of
Surtsey are therefore often unsuitable for nitrogen fixation and
growth of nitrogen-fixing microorganisms. Samples from this area
were analysed for occurence of living
microorganisms in Uppsala, August 1972.
In fact, the nitrogen-fixing activities on Surtsey are well established
and are of major
importance for the nitrogen input and nitrogen economy during the
stage of development.
During the last decade the plants of Honkenya peploides have increased
greatly in number
on Surtsey. Many plants have been buried under sand drifts and new
ones have arrived.
These circumstances must result in accumulation of organic matter
into the soil. Old roots
are decomposed, and from living roots organic substances are exudated
The text above is Based upon a
report by Lars Eric Henriksson and Elisabet Henriksson
Institute of Physiological Botany, University of Uppsala, Uppsala,
Surtsey Research Progress Report IX.
Here you can find more information about:
|| Bird migration
|| Fossils on Surtsey
|| The eruption
February 18th, 2003
last report from Surtsey Research - 2009. Click here
Any questions, or a feeling of knowing more, just get in touch!