———————————–
“… no clear evidence that tropical forests have
modified their functioning in response to climate
change over the past twenty years. Indeed, these
results tend to suggest that the forests are now
rebuilding themselves after disturbances in the
past. Consequently, tropical forests will not be
able to limit the rapid rise in atmospheric
carbon dioxide levels for a long time to come. ”
“… forests are particularly susceptible to
episodes of drought. And some climate forecasting
models have predicted a reduction in rainfall
over tropical forests in the decades to come.”
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Science Daily
http://www.sciencedaily.com/releases/2008/03/080330214448.htm
Tropical Forests Not Likely To Limit Expected
Rapid Rise In Carbon Dioxide, Major Study Suggests
ScienceDaily (Apr. 1, 2008) – More than two
million trees belonging to nearly 5000 species,
growing in tropical forests spread over 12 sites
and three continents, have been monitored since
the 1980s. The aims of this major study were to
analyze the carbon storage capacity of tropical
forests and measure the effects of climate change
on how they function. This work was carried out
by an international team, coordinated by Jérôme
Chave(1), a CNRS researcher. Their results
suggest that the tropical forests studied did
indeed act as carbon sinks, but appeared to react
principally to intrinsic phenomena rather than
climate change. They also demonstrated the
complex functioning of forest ecosystems, their
vulnerability and the importance of efforts to
ensure their conservation.
Tropical forests account for nearly two-thirds of
terrestrial biodiversity and store more than half
of the carbon in the biosphere. Recent studies
have predicted that in a carbon dioxide-enriched
environment, physiological changes will affect
tropical plants; their functioning will be
modified, their biomass will increase and they
will sequester more carbon(2). Under these
conditions, rapidly-growing tree species should
be favored over slow-growing species, and
globally, the carbon sinks represented by
tropical forests should contribute to limiting
atmospheric emissions from fossil fuels.
