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and animal traction as a source of power; 200 years ago, 20% of U.S. agricultural land was devoted
to growing “fuel” to feed livestock (Sexton et al. 2007). Today, many in the world recognize the
many environmental, geopolitical, and economic costs of fossil fuel dependence, and the growing
immediacy of the exhaustion of our fossil fuel reserves. As a result of this recognition, we find
ourselves reconsidering bioenergy, primarily from living plants, as a partial solution to these prob-
lems. Despite the recent attention paid to liquid biofuels, all biomass allocated to energy worldwide
currently represents only approximately 10% of the total of 11,410 million tons of oil equivalent
used per annum (IEA 2007).
The potential advantages of contemporary bioenergy over fossil bioenergy include reduced
or neutral greenhouse gas (GHG) emissions, a renewable and sustainable energy source, and an
invigorated agricultural and/or forestry sector. Proponents of the recent surge in interest in bio-
energy often tout it as a benign alternative to fossil energy. The broader public, at least in the
United States and Europe, was eager to embrace this new energy source, which of course could
be grown in-country and so had the potential of reducing dependence on imported fuels. Brazil
and several nations, had adopted bioenergy much earlier and, in the new era of the bioeconomy,
were hailed as models for the rest of the world (Morgan 2005). As the exhaustion of our fossil fuel
reserves became clearer and petrol prices rose in 2002 and then soared in 2006, industries and
governments around the world quickly poured resources into bioenergy research and production,
tripling worldwide biofuel production between 2002 and 2007 (FAO 2008). Today, there is vigor-
ous scientific debate on a host of issues related to biofuels including how to calculate the actual
GHG reductions from different bioenergy options and the effects of food-based biofuel feedstocks
on world food prices. Although these are important questions, they are beyond the scope of this
chapter, which will focus on how various bioenergy production systems affect ecological systems
and wildlife.
One lesson that has become increasingly clear from recent investments in bioenergy is that
energy policy and production are intertwined in virtually all aspects of the world economy. When
European Union policies meant to provide incentives for biodiesel use raised fears of rainforest
clearing for oil palm plantations in Indonesia (Figure 6.1), and when the expansion of corn-ethanol
production in Iowa contributed to food riots in Mexico, it became obvious that a better understand-
ing of the linkages between bioenergy and the forces driving land-use change was needed. Just
as rapid fluctuations in the price of oil have left bioenergy policy-makers and investors humbled
and wary, biologists concerned with maintaining ecological services find themselves guardedly
hoping that bioenergy can become a step toward a more sustainable way of producing energy. It
is our hope that rather than rejecting bioenergy as trading one set of problems for another, we can
improve the ecological footprint of bioenergy on the landscape and in natural ecosystems. If we
are successful, it will become a smaller and smarter footprint that is more thoughtfully distributed
over the landscape and leaves room for healthy soils, clean water, and enduring rich biodiversity;
in some cases, bioenergy crops may even represent an improvement in habitat over current inten-
sive land use.
6.1.1 t hE m iragE of a B ioEnErgy p anacEa
In the early years of renewed interest in bioenergy (in the United States, 2006-2008), the unin-
tended consequences of an expanded bioenergy economy were rarely considered or at least rarely
reflected in policy. Well-established agricultural systems and government subsidies ensured that
in the United States, Zea mays (corn) would be the initial dominant feedstock for liquid biofuel.
Today corn accounts for more than 90% of the biofuel produced in the United States, although
it represents at best a modest reduction in GHG compared with gasoline and demands large
inputs of fertilizer, herbicides, pesticides, and water (NASS/USDA 2007; Fargione et al. 2008;
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