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What we’ll cover…
• What is the current state of livestock production?
• What is climate change and its effects?
• What is the causal relationship between livestock and climate change?
• How can we mitigate these effects?
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Livestock Production
• Livestock refers to domesticated animals intentionally reared in an agricultural setting to produce food or other products (leather, wool, etc.).– Includes cattle, buffalo, pigs, sheep, horses etc.– A January 2007 count indicated there were around
97 million cattle in the US
• Livestock are raised in agricultural settings such as factory farms, family farms, and cattle ranches.
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Factory Farms v. Family Farms
• Family farms cannot raise the capital to compete with high efficiency factory farms and as a result….
– The number of U.S. farmers dropped by 300,000 from 1978 to 1999
– 2% of Cattle farms account for 40% of the nation’s cattle
– During a 15 year period hog farms decreased by over 400,000, but the number of hogs sold increased
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Factory Farms Today
The number of farms has decreased.
The size of individual farmshas greatly increased.
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Factory Farms Today
Production has increased…
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Factory Farms Today
…so has efficiency.
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Farming Today
According to a USDA report…
91.2% of farms are small family farms-Make up 27.1% of production
7.1% of farms are large-scale family farms-Make up 59.1% of production
1.2% of farms are non-family farms-Make up 13.7% of production
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Factory Farms Today
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Livestock Production Summary
• Farms are getting bigger• Number of farms are decreasing• Factory Farms are taking over the
market and pushing out family farms• Factory farms have high production
rates and lots of waste• Over 9 billion slaughtered, doesn’t
include dairy producing animals!
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Factory Farms and the Environment
• Water Pollution– EPA estimates that animal waste from factory farms has
polluted over 35,000 miles of river in 22 states and contaminated groundwater in 17 states
– Livestock produce about 500 million tons of manure each year which is often sprayed onto croplands or left to sit in lagoons
– Livestock pollution kills fish and contaminates drinking water• In 2001 the EPA forced a hog farm to supply bottled water to
local residents because their farming activities contaminated the drinking water supply
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Factory Farms and the Environment
• Air Pollution, foul odors, and land degradation are just a few more problems that factory farms cause.
Manure pit off a Hog Farm
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Climate Change
• What is climate change?– Greenhouse gases in the Earth’s atmosphere
prevent heat from escaping the atmosphere
• Human caused greenhouse gas emissions account for much of the problem– Carbon Dioxide (CO2)
– Methane (CH4)
– Nitrous Oxide (N2O)
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Climate Change
• Increased concentrations of heat-trapping greenhouse gases is causing temperatures to increase– Earth’s temperature has increased an average
1.2-1.4ºF since 1900 – It’s estimated that if greenhouse gases continue to
increase Earth’s temperature will raise 2.5 to 10.4°F by the end of this century
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Effects of Climate Change
• Rising sea levels
• Shrinking glaciers
• Thawing of permafrost
• Trees blooming earlier
• Changes in range and distribution of plants
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Carbon Dioxide (CO2) and feeding livestock
• Fertilizer is used to grow crops fed to livestock
• Large amounts of CO2 is emitted from the burning of fossil fuels to make this fertilizer
• There is an estimated 40 million Tonnes of CO2 emitted annually from this practice
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CO2 and feeding livestock
• CO2 is emitted during livestock feed production (including electricity)– An estimated 60 million Tonnes
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CO2 and Deforestation
• Deforestation is essential to create land for pasture and growing feed– When forests are harvested or burned
large amounts of CO2 are released into the atmosphere.
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Methane (CH4)
• Enteric Fermentation– Refers to the digestive process in animals in which
microbes ferment food consumed by the animals– Methane is a natural by-product of Enteric
Fermentation• The methane is exhaled
– The amount of methane produced and excreted by the animal depends on the animal’s digestive system as well as the type of feed they consume
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Methane
• Ruminant animals v. non-ruminant animals– Ruminant animals (cattle, buffalo, sheep, goats,
and camels) are the major emitters of methane because of their unique digestive process that occurs in a large “fore-stomach”
• This process allows ruminant animals to digest coarse plant material that non-ruminant animals can’t
– Non-ruminant animals (swine, horses, mules) also emit methane, but at smaller levels
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Methane• Feed quality and quantity effect the
amount of methane emitted– Lower quality feed increases methane
emissions– Higher quantity of feed increases methane
emissions
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Methane
• In 2002 it was estimated that 5.5 tonnes of methane was emitted from enteric fermentation in the US– This accounted for 19% of total methane
emissions in the US
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Methane• Anaerobic decomposition of manure
– Occurs when manure is treated and not left out– Methane is emitted during the decomposition of
manure– Emissions are dependent on the storage of the manure
• Factors like temperature and moisture can facilitate in the growth of methane producing bacteria
– Emissions are dependent on the manure composition which is effected by feed type and the animals digestive system
• Feed that is easier to digest leads to manure with lower manure emissions
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Methane
• Globally, methane emissions from manure have been estimated to total 10 million tonnes– Methane emissions from manure have
been estimated to account for 4% of methane emissions in 2005
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Animal agriculture is the single largest source of methane emissions in the US!
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Nitrous Oxide (N2O)
• Manure management– N2O emissions occur in dry waste
management systems– Emissions have increased 10% from 1990
to 2005– “Unmanaged” manure also emits
greenhouse gases
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Livestock’s Impact• Livestock account for an estimated 9% of
global CO2 emissions!
• Livestock account for an estimated 35-40% of global CH4 emissions!
• Livestock account for an estimated 65% of NO2 emissions!
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Mitigating CO2 emissions
By replacing your “regular car” with a Toyota Prius the average person can
prevent the emission of about 1 tonne of CO2 into the atmosphere
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CO2
By replacing an omnivorous diet with a vegan diet the average person can
prevent the emission of about 1.5 tonnes of CO2 into the atmosphere.
That’s 50% more CO2 saved!
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Mitigating CO2 emissions
• Federal incentives for buying hybrid cars include tax credits of up to $3,150
• Other incentives include stickers that allow hybrids to travel in “carpool” lanes, and free parking in some cities.
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Mitigating CO2 emissions
• Would it be more effective to create incentives for vegan diets? Some things we could try…– Tax incentives for vegan eating– Food stamps only for vegan food– Tax incentives for vegan food producers
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More Mitigation Options• Carbon sequestration
– The EPA suggests carbon sequestration as a solution to climate change. Carbon sequestration is the process in which plants and trees absorb carbon from the atmosphere.
• Deforestation and CO2 emissions– Create incentives for forest conservation
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Mitigation Options
• Enteric Fermentation and CH4 emissions– Increase production efficiency
• Decrease the number of animals• Decrease the time they are emitting methane
– Increase nutrition• Decreases the amount of methane produced
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Mitigation Options
• Manure Management and CH4 and N2O emissions– Be mindful of temperature, moisture levels,
time of storage, and other factors that lead to higher emissions
– Give livestock easily digestable feed to control manure contents
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Mitigation Options
The most effective way to stop greenhouse gas emissions from factory
farms is to maintain a vegan diet!
