An Exploration of Agricultural Land Use Change at Intensive and Extensive Margins

In recent years many studies used economic partial and general equilibrium models to estimate induced land use change (ILUC) emissions due to biofuel production and/or policy. Previous research assumed that all additional harvested crop area came from cultivation of land converted from pasture or forest. However, recent FAO data suggest that there has also been significant addition to harvested area through double cropping and/or returning unused cropland to crop production. This chapter examines the extent to which land intensification can alter the existing estimates for biofuels ILUC emissions. To accomplish this task we (i) reviewed the associated literature; (ii) collected data at the global scale to examine recent trends in land intensification in crop production across the world; (iii) modified a well-known computable general equilibrium model (GTAP-BIO), which has been frequently used in this area to take into account land intensification due to multiple cropping and/or conversion of unused cropland to crop production; (iv) calibrated the model to real world observations, and (v) finally calculated ILUC emissions for several biofuel pathways with and without land intensification. Our results confirm the model with land intensification projects lower ILUC emissions for the examined biofuel pathways. The size of reduction depends on the implemented benchmark database, varies across biofuel pathways, and changes by biofuel production location.