Average yield from historical records and for the GLOBIOM baseline for crops (a) and for non-dairy ruminant meat (b)
Figure 1. Average yield from historical records and for the GLOBIOM baseline for crops (a) and for non-dairy ruminant meat (b). The calculation for crops relies on a selection of 17 crops represented in GLOBIOM. Years 1970, 1990, and 2010 are sourced from the FAO PRODSTAT database (five-year average for 1970 and 1990 and three-year average for 2010). For livestock, trends are derived from  for historic estimations and for projections up to 2030, and the trend is kept constant until 2050. Aggregation for all years is based on the 2000 harvested area and animal production from FAOSTAT. Region definition: DEVD= North America, Oceania and Western Europe; REUR= Eastern Europe and Former USSR; ASIA= South-East and East Asia; LAM= Latin America; WRLD= World average.
In this letter, we investigate the effects of crop yield and livestock feed efficiency scenarios on greenhouse gas (GHG) emissions from agriculture and land use change in developing countries. We analyze mitigation associated with different productivity pathways using the global partial equilibrium model GLOBIOM. Our results confirm that yield increase could mitigate some agriculture-related emissions growth over the next decades. Closing yield gaps by 50% for crops and 25% for livestock by 2050 would decrease agriculture and land use change emissions by 8% overall, and by 12% per calorie produced. However, the outcome is sensitive to the technological path and which factor benefits from productivity gains: sustainable land intensification would increase GHG savings by one-third when compared with a fertilizer intensive pathway. Reaching higher yield through total factor productivity gains would be more efficient on the food supply side but halve emissions savings due to a strong rebound effect on the demand side. Improvement in the crop or livestock sector would have different implications: crop yield increase would bring the largest food provision benefits, whereas livestock productivity gains would allow the greatest reductions in GHG emission. Combining productivity increases in the two sectors appears to be the most efficient way to exploit mitigation and food security co-benefits.