Review of the Impacts on Greenhouse Gas Emissions of Land-Use Changes Induced by Non-food Biomass Production

The recent development of biomass production for energy purposes hasspurred interest in the effects of the land-use changes (LUC) it triggers worldwide,and a surge in the number of scientific articles dealing with this topic. The processesleading from increased biomass demand to environmental impacts in relation to LUCmay be analyzed as a three-step causal chain starting with the identification of reorganizationof agricultural and forestry systems, the assessment of LUC occurring inresponse to these drivers, and the associated environmental impacts. Here we set outto review the impacts of land-use changes induced by non-food biomass productionon greenhouse gases emissions. The selected body of 162 articles displays the followingsalient features: most articles deal with LUC triggered by biofuel production, thepredominant direct LUCs are forest or grassland conversions into annual or perennialcrops, and annual crops conversion into perennial crops; and while Europe and NorthAmerica come first in terms of direct LUC location, a large number of articles alsodeal with direct LUCs occurring in South America and Asia. We show that peerreviewedliterature does not sign a blank check to non-food biomass. The number ofarticles evidencing a net reduction in GHG emissions following a diversion of food/feed crops towards non-food products is only 50% higher than the number of articlesdrawing opposite conclusions. As the LUC-related carbon intensity of biofuelsstrongly depends on where the feedstock is grown and which land-use it replaces, weinvestigated whether specific land-use change patterns can be tied to certain types offeedstocks. Contrary to our expectations, direct forest and grassland conversion issignificantly less often considered for second generation feedstocks or wood