Oil crop sustainability assessment: three years of Brassica napus L. cultivation in North East Italy for biodiesel production.

ABSTRACT: The Renewable Energy Directive (RED - 2009/28/EC,) defines values for greenhouse gas (GHG) emissions of each phase of biofuel production chains. The RED also states that Member State has to define typical GHG emissions for energy crops cultivation at regional level. With this aim, in the framework of “Bioenergie” national project, a software (So.Fi.A.) has been carried out to determine the Life Cycle Assessment of oilseed cultivation in Italian Regions. The paper reports the results of So.Fi.A. analysis focused on winter rapeseed cultivation in NE Italy (Veneto). Overall, during three years, 26 full field trials with different cultivation inputs have been assessed. The incidence of farm inputs on GHG emissions has been assessed showing how nitrogen fertilizers and diesel fuels for soil tillage provide the main contribution. Finally, despite a favorable net energetic balance, GHG emissions from agricultural phase in 10 trials out of 26 were higher than the RED default value. In particular, the defatted residual meals exploitation and, consequently, their impact allocation was necessary to keep impact under the RED threshold. Furthermore, carbon sequestration subsequent to residue soil incorporation has been evaluated, showing how further supply of organic matter were necessary to offset natural soil organic matter depletion by mineralization.