Galdos M. V. auteur aut IRD Cerri C. C. auteur aut IRD Lal R. auteur aut IRD Bernoux Martial auteur aut IRD Feigl B. auteur aut IRD Cerri C. E. P. auteur aut IRD text journalArticle eng text/pdf born digital access Biofuels are both a promising solution to global warming mitigation and a potential contributor to the problem. Several life cycle assessments of bioethanol have been conducted to address these questions. We performed a synthesis of the available data on Brazilian ethanol production focusing on greenhouse gas (GHG) emissions and carbon (C) sinks in the agricultural and industrial phases. Emissions of carbon dioxide (CO2) from fossil fuels, methane (CH4) and nitrous oxide (N2O) from sources commonly included in C footprints, such as fossil fuel usage, biomass burning, nitrogen fertilizer application, liming and litter decomposition were accounted for. In addition, black carbon (BC) emissions from burning biomass and soil C sequestration were included in the balance. Most of the annual emissions per hectare are in the agricultural phase, both in the burned system (2209 out of a total of 2398 kg C-eq), and in the unburned system (559 out of 748 kg C-eq). Although nitrogen fertilizer emissions are large, 111 kg C-eq ha-1 yr-1, the largest single source of emissions is biomass burning in the manual harvest system, with a large amount of both GHG (196 kg C-eq ha-1 yr-1). and BC (1536 kg C-eq ha-1 yr-1). Besides avoiding emissions from biomass burning, harvesting sugarcane mechanically without burning tends to increase soil C stocks, providing a C sink of 1500 kg C ha-1 yr-1 in the 30 cm layer. The data show a C output: input ratio of 1.4 for ethanol produced under the conventionally burned and manual harvest compared with 6.5 for the mechanized harvest without burning, signifying the importance of conservation agricultural systems in bioethanol feedstock production. specialized biofuel carbon footprint global warming life cycle assessment soil carbon sequestration 068 021 084 2 1 37-44 2010 1757-1693 https://www.documentation.ird.fr/hor/fdi:010049542 10.1111/j.1757-1707.2010.01037.x 1757-1693 [F B010049542] https://www.documentation.ird.fr/hor/fdi:010049542 https://www.documentation.ird.fr/intranet/publi/2010/06-1/010049542.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2010-06-21 2017-08-23 fdi:010049542 fre