FNH 355 Lecture Notes - Lecture 12: Sustainable Diet, Greenhouse Gas, Enteric Fermentation
Greenhouse gas emissions and livestock production
The Lancet Commission on Health and Climate Change:
“Consuming a sustainable diet and reducing food waste are ‘no-regret options’… [they will]
lead to direct reductions in the burden of ill-health, enhance community resilience, alleviate
poverty, and address global inequity.”
Sustainable diets as a strategy to mitigate climate change
Consuming a “sustainable diet” reduces GHG emissions and can result in substantial
personal health benefits. Higher in plant-based foods, lower in animal-based foods:
- Low environmental impacts
- Nutritionally adequate
- Safe and healthy
- Culturally acceptable
- Accessible, affordable
Greenhouse gas emissions (GHG) resulting from livestock production
Livestock production accounts for 14.5% of current GHG emissions – roughly equal to
emissions from all forms of transportation combined
Cattle (beef and dairy) – responsible for 65% of the livestock sector’s emissions
How does livestock production contribute to GHG emissions?
- Production, processing, transport of animal feed (45% of total)
½ of these emissions from fertilizing crops, putting manure on pastures
¼ of these emissions due to “land use change”
- Enteric fermentation from ruminants (39% of total)
- Manure storage and processing (10% of total)
Resources required to produce meat
Livestock production accounts for 70% of agricultural land, and 30% of land surface of the
planet (and livestock provides 15% of total food energy)
Use of global water resources in livestock production:
- Livestock sector accounts for 8% of water use
- And it is a major source of water pollution
Eutrophication: water becomes concentrated with nutrients (phosphates, nitrates)
1. Water contamination itself can harm human health
2. Excessive growth of algae
3. Reduced oxygen, other organisms (e.g. fish) die