Multicriteria Assessment of Energy Cropping Systems: Comparing Cropping System Protoypes Based on Miscanthus x Giganteus with Prototypes Based on Annual and Pluriannual Crops.

The production of biofuels from agricultural feedstock causes heated debates related to their environmental impacts and to threats to food security. Miscanthus x giganteus (hereafter called Miscanthus) is expected to produce high yields with low input requirements and is therefore often considered as one of the most promising agricultural feedstock to produce bioethanol. However, it has mainly been studied in experimental conditions. Our study aimed therefore at comparing Miscanthus with other potential agricultural feedstock using data from farming conditions, based on multicriteria ex ante assessment at the cropping system scale. Prototypes of cropping systems were designed for two soil types of Burgundy (France) based on expert knowledge (local advisors and scientists working on energy crops). We focused on two categories of cropping systems: (i) energy-oriented cropping systems including mostly Miscanthus in the crop sequence as energy crop, and (ii) food-energy cropping systems including annual (e.g. triticosecale) and pluriannual crops (e.g. alfalfa) which can be entirely or partly (stems, straws) dedicated to energy production. A cropping system model previously parameterized in the study area was used to implement the ex ante assessment of the prototypes, alongside on-farm data on Miscanthus. Prototypes were also compared with a reference cropping system, i.e. the cropping system mostly used in Burgundy, and based on a rapeseed / winter wheat / winter barley crop sequence). Regarding environmental indicators (nitrate leaching, pesticide use, greenhouse gas emissions) as well as energy ones, cropping systems including Miscanthus performed better than the food-energy cropping systems. However, economic results (i.e. profitability) were very sensitive to Miscanthus yields. Lastly, both categories of cropping systems displayed better environmental performances than the reference cropping system while economic results varied depending on soil types and Miscanthus yields.