GREENHOUSE gas (GHG) emissions by the livestock sector could be cut by as much as 30% through the wider use of existing best practices and technologies, according to a new study released by the U.N. Food & Agriculture Organization (FAO).
The report, "Tackling Climate Change Through Livestock: A Global Assessment of Emissions & Mitigation Opportunities," represents a comprehensive estimate of livestock's contribution to global warming, as well as the sector's potential to help tackle the problem, FAO said.
According to the report, GHG emissions associated with livestock supply chains add up to 7.1 gigatons of carbon dioxide equivalent per year, or 14.5% of all human-caused GHG releases.
The main sources of emissions are: feed production and processing (45% of the total), outputs of GHG during digestion by cows (39%) and manure decomposition (10%), FAO said. The remainder is attributable to the processing and transportation of animal products.
To arrive at its estimates, FAO conducted an analysis of GHG emissions at multiple stages of various livestock supply chains (Figure), including the production and transport of animal feed, on-farm energy use, emissions from animal digestion and manure decay, as well as post-slaughter transport, refrigeration and packaging of animal products.
FAO explained that for this report, it used a modified model, the Global Livestock Environmental Assessment Model, from the model it used for its 2006 "Livestock's Long Shadow" report.
Potential for cuts
By drilling down into where and how emissions occur, the report reveals that significant emission reductions are within the reach of livestock producers, FAO said.
Wider adoption of existing best practices and technologies in feeding, health and husbandry and manure management — as well as greater use of currently underutilized technologies such as biogas generators and energy-saving devices — could help the global livestock sector cut its outputs of global warming gases as much as 30% by becoming more efficient and reducing energy waste, the international agency continued.
Within livestock production systems, there is a strong link between resource use efficiency and the intensity of GHG emissions, the report notes. The potential for achieving emission reductions lies in enabling all livestock producers to change to practices that already are being used by the most efficient operators.
"These new findings show that the potential to improve the sector's environmental performance is significant — and that realizing that potential is, indeed, doable," said Ren Wang, FAO assistant director-general for agriculture and consumer protection.
With global demand for livestock products continuing to grow strongly in almost all developing countries, he added, "it is imperative that the sector starts working now to achieve these reductions to help offset the increases in overall emissions that future growth in livestock production will entail."
FAO said many of the actions it recommends for improving efficiency and reducing GHG emissions would also boost production, which would provide more food and higher incomes, with benefits for food security and poverty reduction.
According to the FAO report, substantial emission reductions can be achieved across all species, systems and regions, with the greatest potential for cuts found in low-productivity ruminant livestock systems in South Asia, Latin America and Africa.
However, FAO said in developed countries — where emission intensities are relatively low but the overall volume of production and, therefore, emissions is high — even small decreases in intensity could still add up to significant gains.
Enabling the livestock production sector — a diverse, global activity that varies greatly from country to country — to become more efficient and reduce emissions will require a mix of policies, incentives and on-the-ground work, FAO said.
There needs to be a focus on practice innovation, supported by knowledge transfer, financial incentives, regulations and raising awareness. In particular, the agency said better policies are needed to facilitate the transfer and use of the best existing efficient practices and technologies and to encourage the development of new solutions.
"Only by involving all stakeholders — the private and public sector, civil society research and academia and international organizations — will we be able to implement solutions that address the livestock sector's diversity and complexity," Wang said.