Global Warming Increasing The Dispersal Of Flora In Northern Forests

ScienceDaily (June 12, 2009) — As a result of stronger winds caused by
global warming, seeds and pollen are being carried over longer
distances. An increase in temperature of only a couple of degrees may
increase the dispersal of plants in Northern forests and the spread of
plant species into forest clearings after felling or forest fires.

University of Helsinki researcher Anna Kuparinen headed the
international research into the impact of global warming on seed and
pollen dispersal. The goal was to learn whether global warming would
accelerate the dispersal of plant populations in forests. The research
group utilised the micrometeorological data gathered over a decade at
the Hyytiälä Forestry Field Station. Carried out mainly at the
University of Potsdam in Germany, the research findings were published
in Proceedings of the Royal Society B on 10 June 2009.

Seed and pollen dispersal profoundly affects the dynamics and genetic
variation of plant populations. Spreading into more favourable areas
will help them survive in the warming climate. Wind conditions play a
key role, as turbulent vertical streams, in particular, spread seeds
very efficiently, even over long distances.

The researchers also discovered that a temperature that is only three
degrees Celsius warmer increased the dispersal of seeds and the speed
at which populations spread throughout the growth season. Particularly
for those plants which have light seeds, the annual spreading speed
increased dramatically, by approximately 30–40 meters.

On the basis of these results, it seems that global warming
accelerates the spread of plants, but it will not alone be sufficient
to help plant populations to relocate to new vegetation zones.
However, on a more local level, global warming may have a significant
impact, as original and newly introduced species spread faster from
one place to another and take over new patches of habitat. The
combined effects of global warming are difficult to predict, and the
research carried out by Kuparinen’s team illustrates the complexity of
ways in which increased temperatures may affect the flora in Northern
forest habitats.

The above story is reprinted (with editorial adaptations by
ScienceDaily staff) from materials provided by University of Helsinki,
via AlphaGalileo.

-- http://www.sciencedaily.com/releases...0611065853.htm