“Our model predicts that indirect land use will be responsible for substantially more carbon loss (up to twice as much) than direct land use; however, because of predicted increases in fertilizer use, nitrous oxide emissions will be more important than carbon losses themselves in terms of warming potential.”
Melillo, J. et al (2009): Indirect Emissions from Biofuels: How Important? Science vol. 326, 4 December 2009 pp. 1397-1399
http://www.sciencemag.org/cgi/reprint/326/5958/1397.pdf
“Policymakers would (…) be wise to assign emissions factors for ILUC that are high enough to provide a level of reasonable assurance that hoped for greenhouse gas reductions will be real.”
Searchinger, T. (2010) Biofuels and the need for additional carbon. Environmental Research Letters 5 (2010) 024007.
http://iopscience.iop.org/1748-9326/5/2/024007/fulltext
“Our results demonstrate that the net effect of biofuel production via clearing of carbon-rich habitats is to increase CO2 emissions for decades or centuries relative to fossil fuel use.”
Fargione, J.; Hill, J.; Tilman, D.; Polasky, S., and Hawthorne, P., 2008. Land clearing and the biofuel carbon debt. Science, 29/02/2008, pp. 1235–1238
http://www.sciencemag.org/cgi/content/abstract/319/5867/1235
“By using a worldwide agricultural model to estimate emissions from land-use change, we found that corn-based ethanol, instead of producing a 20% savings, nearly doubles greenhouse emissions over 30 years and increases greenhouse gases for 167 years. Biofuels from switchgrass, if grown on U.S. corn lands, increase emissions by 50%. This result raises concerns about large biofuel mandates and highlights the value of using waste products.”
Searchinger, T. et al (2008): Use of U.S. Croplands for Biofuels Increases Greenhouse Gasses through Emissions from Land Use Change. Science, 08/02/2008, pp. 1238-1240
http://www.sciencemag.org/cgi/content/abstract/1151861
“One environmental impact that has raised serious concerns is loss of Amazonian forest through indirect land use changes (ILUC), whereby mechanized agriculture encroaches on existing pastures, displacing them to the frontier.”
“The voluntary moratorium on primary forest conversions by Brazilian soy farmers has failed to stop the deforestation effects of expanding soy production. Thus, environmental policy in Brazil must pay attention to ILUC, which can complicate efforts to achieve its REDD targets.”
Arima, E.Y. et al., Abstract “Statistical confirmation of indirect land use change in the Brazilian Amazon”, Environmental Research Letters, 6, (April-June 2011) http://iopscience.iop.org/1748-9326/6/2/024010/fulltext/