Flowers are Losing Their Scent
Pollution is dulling the scent of flowers and impeding
some of the most basic processes of nature, disrupting insect life
and imperilling food supplies, a new study suggests.
The
potentially hugely significant research – funded
by the blue-chip US National Science Foundation – has found
that gases mainly formed from the emissions of car exhausts prevent
flowers from attracting bees and other insects in order to pollinate
them. And the scientists who have conducted the study fear that
insects' ability to repel enemies and attract mates may also
be
impeded.
The researchers – at the University of Virginia – say
that pollution is dramatically cutting the distance travelled by
the scent of flowers. Professor Jose Fuentes, who led the study,
said: "Scent molecules produced by flowers in a less polluted
environment could travel for roughly 1,000 to 1,200 metres. But
today they may travel only 200 to 300 metres. This makes it increasingly
difficult for bees and other insects to locate the flowers."
The researchers – who worked on the scent given off by snapdragons – found
that the molecules are volatile, and quickly bond with pollutants
such as ozone and nitrate radicals, mainly formed from vehicle
emissions. This chemically alters the molecules so that they no
longer smell like flowers. A vicious cycle is therefore set up
where insects struggle to get enough food and the plants do not
get pollinated enough to proliferate.
Already bees – which pollinate most of the world's crops – are
in unprecedented decline in Britain and across much of the globe.
At least a quarter of America's 2.5 million honey bee colonies
have been mysteriously wiped out by colony collapse disorder (CCD),
where hives are found suddenly deserted.
The crisis
has now spread to Europe. Politicians insist that CCD has not
yet been found
in Britain, but the insects have been declining
here too, and the agriculture minister Lord Rooker has warned that "the
honey bee population could be wiped out in 10 years".
The researchers
do not believe that they have found the cause of CCD, but say
that pollution
is making life more difficult for
bees and other insects in many ways."
April 20, 2008
From the Independent