资源环境科技发展态势分析平台

Agricultural intensification, and particularly double cropping, has been suggested as a practical strategy to reconcile biofuel feedstock production with other land-use priorities. Here we assess ethanol production under conditions representative of current practice in the west central region of Brazil: maize grown as a second crop with soybean on land that formerly grew a single soybean crop, and energy processed from a combined heat and power plant using plantation-grown eucalyptus chips. For maize ethanol thus produced we find large reductions in greenhouse gas emissions compared to gasoline, and considerable economic and employment benefits at both local and national levels. We also calculate reduced land-use emissions with maize ethanol production compared to the situation without it. Our study thus documents an example of how the complex linkages of bioenergy to food production and security, environment and economic development can be-and indeed appear to be-managed for positive outcomes using current technology.

Double cropping can increase production from a given area of land. This study finds that maize ethanol produced from a second crop with soybeans in west central Brazil can reduce greenhouse gas emissions compared with gasoline and also have economic and employment benefits.