A new study finds that it will take more than 75 years
for the carbon emissions saved through the use of biofuels to compensate
for the carbon lost when biofuel plantations are established on
forestlands. If the original habitat was peatland, carbon balance would
take more than 600 years.
The oil palm, increasingly used as a source for biofuel, has replaced
soybean as the world’s most traded oilseed crop. Global production of
palm oil has increased exponentially over the past 40 years. In 2006, 85
percent of the global palm-oil crop was produced in Indonesia and
Malaysia, countries whose combined annual tropical forest loss is around
20,000 square kilometers.
Conversion of forest to oil palm also results in significant
impoverishment of both plant and animal communities. Other tropical
crops suitable for biofuel use, like soybean, sugar cane and jatropha,
are all likely to have similar impacts on climate and biodiversity.
“Biofuels are a bad deal for forests, wildlife and the climate if
they replace tropical rain forests,” says research scientist Finn
Danielsen, lead author of the study. “In fact, they hasten climate
change by removing one of the world’s most efficient carbon storage
tools, intact tropical rain forests.”
As countries strive to meet obligations to reduce carbon emissions
under one international agreement (Kyoto Protocol), they may not only
fail to meet their obligations under another (Convention on Biological
Diversity) but may actually hasten global climate change.
According to the study, reducing deforestation is likely to represent
a more effective climate-change mitigation strategy than converting
forest for biofuel production, and it may help nations meet their
international commitments to reduce biodiversity loss.
Alternatively, planting biofuels on degraded grasslands instead of
tropical rain forests would lead to a net removal of carbon from the
atmosphere in 10 years. Any biofuel plantations in tropical forest
regions should be considered only in former forest land which has
already been severely degraded to support only grassy vegetation.
“The EU and the US should only import and subsidize bio-fuel from
guaranteed sustainable productions and only from countries which can
demonstrate that their forests are sustainably managed,” says Danielsen.
Tropical forests contain more than half of the Earth’s terrestrial
species. They also store around 46 percent of the world’s living
terrestrial carbon, and 25 percent of total net global carbon emissions
may stem from deforestation. There is therefore an inherent
contradiction in any strategy to clear tropical forest to grow crops for
so-called carbon-neutral fuels.
There are signs that part of the oil-palm industry is trying to
minimize the impact its plantations have on biodiversity, but there is
currently little effort to mitigate potential climate impacts
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