Biofuel Farming Looks to Be an Environmental Disaster
Growing corn for ethanol may increase greenhouse gases for over a
century.
Discover magazine February, Better Planet Special Issue, snippett
by Jennifer Barone and Amber Fields
THE STUDIES "Land Clearing and the Carbon Biofuel Debt" by Joseph
Fargione et al., and "Use of U.S. Croplands for Biofuels Increases
Greenhouse Gases Through Emissions From Land Use Change" by Timothy
Searchinger et al., both published in the February 7, 2008, issue of
Science.
THE QUESTION Will switching from fossil fuels to biofuels really
reduce greenhouse gases? We take a close look at two big,
controversial studies that examine carbon emissions from the
ecosystems torn down to produce biofuels.
THE METHODS Throughout the Amazonian rain forest and the savanna of
Brazil, enormous swaths of land are being converted to farms for
growing soybeans and sugarcane--all for use in creating biofuels. The
tropical rain forest and peatland of Indonesia and Malaysia and the
grasslands of the United States are also being converted to biofuel
crops. It is a disturbing trend, says Joseph Fargione, regional
science director at the Nature Conservancy, who conducted the first of
the two studies examined here. With his colleagues Fargione took a
close look at how the areas being transformed into farmland have acted
as carbon dioxide storage systems. Trees, grass, and other flora take
in the gas, Fargione says, incor****ating the carbon into their
structures. But when the land is converted for agriculture, the plants
are cut down, burned, or processed, and the stored carbon is
eventually released back into the atmosphere as greenhouse gases.
Using numbers from nearly 50 previous studies, Fargione's team
calculated the amount of carbon stored in these landscapes and the up-
front carbon cost for each acre of land converted to produce biofuels.
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