Synergies and trade-offs between the greenhouse gas emissions and biodiversity performances of global livestock production.

We provide the first global environmental assessment of livestock production that includes both greenhouse gas (GHG) emissions and biodiversity criteria. We compared performances on these two environmental criteria across scales, commodities (dairy and beef cattle) and production systems (grassland and mixed). To do this, we combined a global model computing the greenhouse gas emissions of livestock with the Mean Species Abundance biodiversity indicator to quantify the biodiversity impact of livestock through land use. Results showed weaker synergies and more trade-offs between environmental criteria in grassland than in mixed production systems. Efficiency in the utilization of feed and their associated land use is likely to drive the synergies in mixed production systems. Grassland systems based on extensive feed land use with high biodiversity values may have contrasted GHG emissions performances. Our global mapping of the relationships between environmental criteria could be used for spatially targeting decisions and actions.