Generated Summary
This document provides key facts and findings regarding the environmental impact of livestock, specifically focusing on greenhouse gas (GHG) emissions. It examines the sources of these emissions, their contribution to overall anthropogenic GHGs, and potential mitigation strategies. The analysis, based on detailed data sets, identifies cattle as the primary species responsible for emissions, followed by activities like feed production and processing. The document emphasizes the role of fossil fuel consumption in supply chains and highlights emission intensities across different commodities. Efficient practices for reducing emissions are discussed, along with mitigation potential, including improving animal and herd efficiency, better grazing land management, and precision feeding. Key policy areas for action, such as extension and agricultural support services, research and development, and financial incentives, are also explored to facilitate practice changes and enhance mitigation efforts.
Key Findings & Statistics
- Total emissions from global livestock: 7.1 Gigatonnes of CO2-equiv per year, representing 14.5 percent of all anthropogenic GHG emissions.
- Cattle responsible for approximately 65% of the livestock sector’s emissions.
- Feed production and processing (including land use change) and enteric fermentation from ruminants are the two main sources of emissions, representing 45 and 39 percent of total emissions, respectively.
- Manure storage and processing represent 10 percent of emissions.
- Consumption of fossil fuel along supply chains accounts for about 20 percent of the livestock sector’s emissions.
- Beef and cattle milk contribute 41 percent and 20 percent, respectively, to the sector’s overall GHG outputs.
- Pig meat (9 percent), buffalo milk and meat (8 percent), chicken meat and eggs (8 percent), and small ruminant milk and meat (6 percent) also contribute to emissions.
- About 44 percent of livestock emissions are in the form of methane (CH4).
- 2 Gt CO2-eq of N2O per annum, or 53 percent of anthropogenic N2O emissions (IPCC, 2007)
- 3.1 Gt CO2-eq of CH4 per annum, or 44 percent of anthropogenic CH4 emissions (IPCC, 2007)
- Gt CO2-eq of CO2 per annum, or 5 percent of anthropogenic CO2 emissions (IPCC, 2007)
- Emission intensities: highest for beef (almost 300 kg CO2-eq per kilogram of protein produced), followed by meat and milk from small ruminants (165 and 112kg CO2-eq.kg respectively). Cow milk, chicken products and pork have lower global average emission intensities (below 100 CO2-eq/kg.).
- FAO’s new report estimates that partially reducing this gap within existing production systems could cut emissions by about 30 percent.
- Grassland carbon sequestration could further contribute to the mitigation effort by, with global estimates of about 0.6 GT CO2-eq per year.
Other Important Findings
- The document notes that the figure for total emissions is in line with a previous assessment, although based on more detailed analysis and improved data sets.
- Enteric emissions and feed production dominate emissions from ruminant production.
- In pig supply chains, emissions are related to feed supply and manure storage, while feed supply is the bulk of emissions in poultry production.
- Variability in emission intensities exists within each commodity type due to different practices and inputs used.
- There’s a direct link between GHG emission intensities and the efficiency with which producers use natural resources.
- Interventions to reduce emissions are based on technologies and practices that improve production efficiency.
- Improved breeding and animal health interventions to allow herd sizes to shrink will also help.
- Better management of grazing lands could improve productivity and create carbon sinks.
- “Precision feeding,” breeding, and better animal health care offer ways to reduce emissions in monogastric production.
Limitations Noted in the Document
- The document mentions that the two figures for total emissions cannot be accurately compared as reference periods and sources differ.
- The report highlights a ’emission intensity gap’ within production systems, this may be difficult to address fully
- The document acknowledges that mitigation interventions will need to be tailored to local objectives and conditions.
- Variability in emission intensities at the sub-global level makes broad generalizations challenging.
- The estimates of potential emission reductions from the gap between high and low emission operations are based on models and may have limitations.
Conclusion
The document underscores the significant contribution of livestock to global GHG emissions, emphasizing the need for sustainable practices within the sector. Cattle are identified as the major contributor, with feed production, enteric fermentation, and fossil fuel consumption in supply chains as key emission sources. The document highlights the importance of improving animal and herd efficiency, better grazing land management, and adopting precision feeding techniques. The potential for reducing emissions through these practices is substantial, with a focus on closing the ’emission intensity gap’ between high and low-emitting operations. The report emphasizes the role of various policy areas, including agricultural support services, research and development, financial incentives, and international agreements, in facilitating the transition to more sustainable livestock systems. The document concludes by advocating for integrated strategies and international cooperation to address the complex challenge of reducing livestock’s environmental impact. The actionable insight include the fact that improving existing practices in current systems can lead to approximately 30 percent reduction in emissions, and that grassland carbon sequestration could significantly contribute to mitigation, signaling a pathway toward a more sustainable future for the livestock industry.