* Plants flowering 8.5 times faster than predicted
* Changes have knock-on effect for food chain, ecosystems
By Nina Chestney
LONDON, May 2 Plants are flowering faster than
scientists predicted in response to climate change, research in
the United States showed on Wednesday, which could have
devastating knock-on effects for food chains and ecosystems.
Global warming is having a significant impact on hundreds of
plant and animal species around the world, changing some
breeding, migration and feeding patterns, scientists say.
Increased carbon dioxide concentration in the atmosphere
from burning fossil fuels can affect how plants produce oxygen,
while higher temperatures and variable rainfall patterns can
change their behaviour.
"Predicting species' response to climate change is a major
challenge in ecology," said researchers at the University of
California San Diego and several other U.S. institutions.
They said plants had been the focus of study because their
response to climate change could affect food chains and
ecosystem services such as pollination, nutrient cycles and
The study, published on the Nature website, draws on
evidence from plant life cycle studies and experiments across
four continents and 1,634 species. It found that some
experiments had underestimated the speed of flowering by 8.5
times and growing leaves by 4 times.
"Across all species, the experiments under-predicted the
magnitude of the advance - for both leafing and flowering - that
results from temperature increases," the study said.
The design of future experiments may need to be improved to
better predict how plants will react to climate change, it said.
Plants are essential to life on Earth. They are the base of
the food chain, using photosynthesis to produce sugar from
carbon dioxide and water. They expel oxygen which is needed by
nearly every organism which inhabits the planet.
Scientists estimate the world's average temperature has
risen by about 0.8 degrees Celsius since 1900, and nearly 0.2
degrees per decade since 1979.
So far, efforts to cut emissions of planet-warming
greenhouse gases are not seen as sufficient to prevent the Earth
heating up beyond 2 degrees C this century - a threshold
scientists say risks an unstable climate in which weather
extremes are common, leading to drought, floods, crop failures
and rising sea levels.
The study can be viewed at www.nature.com/nature
(Reporting by Nina Chestney; Editing by Janet Lawrence)