Modelling alternative management scenarios of economic and environmental sustainability of beef finishing systems.

The livestock industry, and particularly beef production, is recognised as an important source of greenhouse gas (GHG) emissions linked to climate change. The complexity of beef systems means that appropriate GHG mitigating strategies depend on local conditions, requiring tailored entry points to be identified and evaluated. Using Scotland as a case study, here we combine a bio-economic simulation model and farm-level carbon footprinting tool to study the environmental impact of a range of beef production scenarios, and trade-offs generated between mitigating emissions and increasing farm profitability. To measure the environmental impact of finishing duration, type and gender selection of beef fattening systems, emissions were grouped into five categories: (1) land and crops, (2) enteric emissions, (3) manure, (4) feed and bedding, and (5) fuel and electricity. Results suggest that more intensive shorter duration systems have the lowest environmental impact of all the systems investigated. However, medium duration (i.e. 18-24 months) pasture-based beef production systems in Scotland were found to achieve a balance between financial returns and environmental performance.