Environmental effects of meat production
Encyclopedia
The environmental impact of meat production includes pollution and the use of resources such as fossil fuels, water, and land. According to a 2006 report by the Livestock, Environment And Development Initiative, the livestock industry is one of the largest contributors to environmental degradation
worldwide, and modern practices of raising animals for food contribute on a "massive scale" to air and water pollution
, land degradation, climate change
, and loss of biodiversity
. The initiative concluded that "the livestock sector emerges as one of the top two or three most significant contributors to the most serious environmental problems, at every scale from local to global." In 2006 FAO estimated that meat industry contributes 18% of all emissions of greenhouse gasses. This figure was challenged in 2009 by two World-Watch researchers who estimated a 51% minimum, however this paper has not been peer reviewed.
Animals fed on grain need more water than grain crops. In tracking food animal production from the feed through to the dinner table, the inefficiencies of meat, milk
and egg
production range from a 4:1 energy input to protein output ratio up to 54:1. The result is that producing animal-based food is typically much less efficient than the harvesting of grains, vegetables, legumes, seeds and fruits for direct human consumption.
Relatedly, the production and consumption of meat and other animal products is associated with the
clearing of rainforests, resource depletion, air and water pollution, land and economic inefficiency, species extinction, and other environmental harms.
Although it requires less land for the livestock, factory farming requires large quantities of feed.The growing of cereals for feed in turn requires substantial areas of land. Free-range animal production requires land for grazing, which has led to encroachment on undeveloped lands as well as clear cutting of forests. Such expansion has increased the rate of species extinction
and damaged the services offered by nature, such as the natural processing of pollutants.
According to the United Nations
, "Ranching-induced deforestation is one of the main causes of loss of some unique plant and animal species in the tropical rainforests of Central and South America as well as carbon release in the atmosphere." The Food and Agriculture Organization
(FAO) agrees, saying that "Expanding livestock production is one of the main drivers of the destruction of tropical rain forest
s in Latin America, which is causing serious environmental degradation in the region." An earlier FAO study found that 90% of deforestation is caused by unsustainable agricultural practices. Logging and plantation forestry, though not as major contributors to deforestation, play a greater role in forest degradation.
Producing a certain quantity of food in meat requires much more water than producing the same amount of food in grain.
According to the vegetarian author John Robbins, it roughly takes 60, 108, 168, and 229 pounds of water to produce a pound of potatoes, wheat, corn and rice respectively. He reports that a pound of beef however, requires 12,000 gallons of water.
David Pimentel explained of his calculations that:
and riparian ecosystem
s are also associated with meat production in the United States; In the Western United States
80% of stream
and riparian habitat
s have been negatively impacted by livestock grazing. This has resulted in increased phosphate
s, nitrate
s, decreased dissolved oxygen, increased temperature, turbidity
, and eutrophication
events, and reduced species diversity
(Belsky et al., 1999). In the Eastern United States
waste release from pork farms have also been shown to cause large-scale eutrophication of bodies of water, including the Mississippi River
and Atlantic Ocean (Palmquist, et al., 1997).
At a global scale, a 29 November 2006 United Nations
report called the Livestock's Long Shadow - Environmental Issues and Options
assesses the meat and livestock industry to contribute to about 9% of total anthropogenic carbon dioxide emissions, including 37% of methane and 65% of nitrous oxide emissions.
At a local level, livestock represents up to half of New Zealand
's greenhouse gas emissions, and nearly 20% of the total methane emissions of the United States of America.
Indirect effects account for most of agricultural greenhouse gas emissions, and are attributed to emissions of nitrous oxides and other gases from concentrated livestock operations
and from microbial activities in soil and water following applications of fertilizers . Greenhouse gas emissions are not limited to animal husbandry; for instance, in many countries where rice is the main cereal crop
, rice cultivation is responsible for most of the methane emissions.
The production of protein from grain-fed animals requires eight times as much fossil-fuel energy as the production of plant protein. According to an article in Environmental Health Perspectives
, typical feedlot husbandry of cattle requires an input of 35 kcal of fossil fuel to produce one kcal of food energy in beef, far more than that required for comparable plants.
A 2006 study at the University of Chicago
concluded that a person switching from a typical American diet to eating 20% less meat, or about 6 oz a day would prevent the emission of 1485 kg of carbon dioxide
. The difference exceeds that of an individual switching from a Toyota Camry
to the hybrid Toyota Prius
, and collectively amounts to over 6% of the total U.S. greenhouse gas
emissions.
This view, however, reflects the situation in the developed world and does not take into account the situation in most third world countries. In the developing world, notably Asia
and Africa
, fossil fuels are seldom used to transport feed for farm animals. Sheep or goats, for example, require no fuel, since they graze on farmlands, while bales of hay
for bovines are still transported mainly using bullock cart
s or similar devices. Little to no meat processing takes place in the vast majority of the developing world. Animals are also often herded to the place of slaughter (with the exception of poultry) resulting in a very low use of fossil fuels. In fact, farm animals in the developing world are used for multiple purposes, from providing draught power to transportation, while also serving as meat once they reach the end of their economic lives.
A more efficient use of animal waste may be a contributing factor in sustainability. The by-products of slaughtered animals can be used to provide biogas
. Train
s running on this fuel are already in operation in Sweden
. The use of biogas to run mass transit
is likely only possible as a side effect of industrial agriculture
.
. Individual commitment is being increasingly supported by local initiatives, such as the meat-free days of the Belgian
city of Ghent
(or Veggiedag) which imposes vegetarian-only food in public canteens for civil servants and elected concillors, soon in all schools, and promotes vegetarian eating options in town through the distribution of "veggie street maps".
The UN has admitted a report linking livestock to global warming exaggerated the impact of eating meat on climate change.
Dr Frank Mitloehner, from the University of California at Davis (UCD), said meat and milk production generates less greenhouse gas than most environmentalists claim and that the emissions figures were calculated differently to the transport figures, resulting in an “apples-and-oranges analogy that truly confused the issue”.
The meat figure had been reached by adding all greenhouse-gas emissions associated with meat production, including fertilizer production, land clearance, methane emissions and vehicle use on farms, whereas the transport figure had only included the burning of fossil fuels. In the original press release in which Dr. Mitloehner's assertions appear, it transpires that his work was funded by a $26,000 grant from the Beef Checkoff Program. In addition, his comments do not state that the UN's calculations are false, but rather that they considered the entire commodity chain, which they did not do for transport.
Environmental degradation
Environmental degradation is the deterioration of the environment through depletion of resources such as air, water and soil; the destruction of ecosystems and the extinction of wildlife...
worldwide, and modern practices of raising animals for food contribute on a "massive scale" to air and water pollution
Pollution
Pollution is the introduction of contaminants into a natural environment that causes instability, disorder, harm or discomfort to the ecosystem i.e. physical systems or living organisms. Pollution can take the form of chemical substances or energy, such as noise, heat or light...
, land degradation, climate change
Climate change
Climate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. It may be a change in average weather conditions or the distribution of events around that average...
, and loss of biodiversity
Biodiversity
Biodiversity is the degree of variation of life forms within a given ecosystem, biome, or an entire planet. Biodiversity is a measure of the health of ecosystems. Biodiversity is in part a function of climate. In terrestrial habitats, tropical regions are typically rich whereas polar regions...
. The initiative concluded that "the livestock sector emerges as one of the top two or three most significant contributors to the most serious environmental problems, at every scale from local to global." In 2006 FAO estimated that meat industry contributes 18% of all emissions of greenhouse gasses. This figure was challenged in 2009 by two World-Watch researchers who estimated a 51% minimum, however this paper has not been peer reviewed.
Animals fed on grain need more water than grain crops. In tracking food animal production from the feed through to the dinner table, the inefficiencies of meat, milk
Milk
Milk is a white liquid produced by the mammary glands of mammals. It is the primary source of nutrition for young mammals before they are able to digest other types of food. Early-lactation milk contains colostrum, which carries the mother's antibodies to the baby and can reduce the risk of many...
and egg
Egg (food)
Eggs are laid by females of many different species, including birds, reptiles, amphibians, and fish, and have probably been eaten by mankind for millennia. Bird and reptile eggs consist of a protective eggshell, albumen , and vitellus , contained within various thin membranes...
production range from a 4:1 energy input to protein output ratio up to 54:1. The result is that producing animal-based food is typically much less efficient than the harvesting of grains, vegetables, legumes, seeds and fruits for direct human consumption.
Relatedly, the production and consumption of meat and other animal products is associated with the
clearing of rainforests, resource depletion, air and water pollution, land and economic inefficiency, species extinction, and other environmental harms.
Grazing and land use
Extinction
In biology and ecology, extinction is the end of an organism or of a group of organisms , normally a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point...
and damaged the services offered by nature, such as the natural processing of pollutants.
According to the United Nations
United Nations
The United Nations is an international organization whose stated aims are facilitating cooperation in international law, international security, economic development, social progress, human rights, and achievement of world peace...
, "Ranching-induced deforestation is one of the main causes of loss of some unique plant and animal species in the tropical rainforests of Central and South America as well as carbon release in the atmosphere." The Food and Agriculture Organization
Food and Agriculture Organization
The Food and Agriculture Organization of the United Nations is a specialised agency of the United Nations that leads international efforts to defeat hunger. Serving both developed and developing countries, FAO acts as a neutral forum where all nations meet as equals to negotiate agreements and...
(FAO) agrees, saying that "Expanding livestock production is one of the main drivers of the destruction of tropical rain forest
Tropical and subtropical moist broadleaf forests
Tropical and subtropical moist broadleaf forests , also known as tropical moist forests, are a tropical and subtropical forest biome....
s in Latin America, which is causing serious environmental degradation in the region." An earlier FAO study found that 90% of deforestation is caused by unsustainable agricultural practices. Logging and plantation forestry, though not as major contributors to deforestation, play a greater role in forest degradation.
Water resources
| Hoekstra & Hung (2003) |
Chapagain & Hoekstra (2003) |
Zimmer & Renault (2003) |
Oki et al. (2003) |
Average | |
| Beef | 15977 | 13500 | 20700 | 16726 | |
| Pork | 5906 | 4600 | 5900 | 5469 | |
| Cheese | 5288 | 5288 | |||
| Poultry | 2828 | 4100 | 4500 | 3809 | |
| Eggs | 4657 | 2700 | 3200 | 3519 | |
| Rice | 2656 | 1400 | 3600 | 2552 | |
| Soybeans | 2300 | 2750 | 2500 | 2517 | |
| Wheat | 1150 | 1160 | 2000 | 1437 | |
| Maize | 450 | 710 | 1900 | 1020 | |
| Milk | 865 | 790 | 560 | 738 | |
| Potatoes | 160 | 105 | 133 |
Producing a certain quantity of food in meat requires much more water than producing the same amount of food in grain.
According to the vegetarian author John Robbins, it roughly takes 60, 108, 168, and 229 pounds of water to produce a pound of potatoes, wheat, corn and rice respectively. He reports that a pound of beef however, requires 12,000 gallons of water.
David Pimentel explained of his calculations that:
Effects on aquatic ecosystems
Significant negative effects of aquaticAquatic ecosystem
An aquatic ecosystem is an ecosystem in a body of water. Communities of organisms that are dependent on each other and on their environment live in aquatic ecosystems. The two main types of aquatic ecosystems are marine ecosystems and freshwater ecosystems....
and riparian ecosystem
Ecosystem
An ecosystem is a biological environment consisting of all the organisms living in a particular area, as well as all the nonliving , physical components of the environment with which the organisms interact, such as air, soil, water and sunlight....
s are also associated with meat production in the United States; In the Western United States
Western United States
.The Western United States, commonly referred to as the American West or simply "the West," traditionally refers to the region comprising the westernmost states of the United States. Because the U.S. expanded westward after its founding, the meaning of the West has evolved over time...
80% of stream
Stream
A stream is a body of water with a current, confined within a bed and stream banks. Depending on its locale or certain characteristics, a stream may be referred to as a branch, brook, beck, burn, creek, "crick", gill , kill, lick, rill, river, syke, bayou, rivulet, streamage, wash, run or...
and riparian habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...
s have been negatively impacted by livestock grazing. This has resulted in increased phosphate
Phosphate
A phosphate, an inorganic chemical, is a salt of phosphoric acid. In organic chemistry, a phosphate, or organophosphate, is an ester of phosphoric acid. Organic phosphates are important in biochemistry and biogeochemistry or ecology. Inorganic phosphates are mined to obtain phosphorus for use in...
s, nitrate
Nitrate
The nitrate ion is a polyatomic ion with the molecular formula NO and a molecular mass of 62.0049 g/mol. It is the conjugate base of nitric acid, consisting of one central nitrogen atom surrounded by three identically-bonded oxygen atoms in a trigonal planar arrangement. The nitrate ion carries a...
s, decreased dissolved oxygen, increased temperature, turbidity
Turbidity
Turbidity is the cloudiness or haziness of a fluid caused by individual particles that are generally invisible to the naked eye, similar to smoke in air. The measurement of turbidity is a key test of water quality....
, and eutrophication
Eutrophication
Eutrophication or more precisely hypertrophication, is the movement of a body of water′s trophic status in the direction of increasing plant biomass, by the addition of artificial or natural substances, such as nitrates and phosphates, through fertilizers or sewage, to an aquatic system...
events, and reduced species diversity
Species diversity
Species diversity is an index that incorporates the number of species in an area and also their relative abundance. It is a more comprehensive value than species richness....
(Belsky et al., 1999). In the Eastern United States
Eastern United States
The Eastern United States, the American East, or simply the East is traditionally defined as the states east of the Mississippi River. The first two tiers of states west of the Mississippi have traditionally been considered part of the West, but can be included in the East today; usually in...
waste release from pork farms have also been shown to cause large-scale eutrophication of bodies of water, including the Mississippi River
Mississippi River
The Mississippi River is the largest river system in North America. Flowing entirely in the United States, this river rises in western Minnesota and meanders slowly southwards for to the Mississippi River Delta at the Gulf of Mexico. With its many tributaries, the Mississippi's watershed drains...
and Atlantic Ocean (Palmquist, et al., 1997).
Fossil fuel consumption and greenhouse gas emissions
United Nations
The United Nations is an international organization whose stated aims are facilitating cooperation in international law, international security, economic development, social progress, human rights, and achievement of world peace...
report called the Livestock's Long Shadow - Environmental Issues and Options
Livestock's Long Shadow
Livestock's Long Shadow - Environmental Issues and Options is a United Nations report, released by the Food and Agriculture Organization of the United Nations on 29 November 2006, that "aims to assess the full impact of the livestock sector on environmental problems, along with potential technical...
assesses the meat and livestock industry to contribute to about 9% of total anthropogenic carbon dioxide emissions, including 37% of methane and 65% of nitrous oxide emissions.
At a local level, livestock represents up to half of New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
's greenhouse gas emissions, and nearly 20% of the total methane emissions of the United States of America.
Indirect effects account for most of agricultural greenhouse gas emissions, and are attributed to emissions of nitrous oxides and other gases from concentrated livestock operations
Factory farming
Factory farming is a term referring to the process of raising livestock in confinement at high stocking density, where a farm operates as a factory — a practice typical in industrial farming by agribusinesses. The main products of this industry are meat, milk and eggs for human consumption...
and from microbial activities in soil and water following applications of fertilizers . Greenhouse gas emissions are not limited to animal husbandry; for instance, in many countries where rice is the main cereal crop
Cereal
Cereals are grasses cultivated for the edible components of their grain , composed of the endosperm, germ, and bran...
, rice cultivation is responsible for most of the methane emissions.
The production of protein from grain-fed animals requires eight times as much fossil-fuel energy as the production of plant protein. According to an article in Environmental Health Perspectives
Environmental Health Perspectives
Environmental Health Perspectives is a peer-reviewed open-access medical journal published monthly by the National Institute of Environmental Health Sciences. According to the Journal Citation Reports, the journal has a 2009 impact factor of 6.191....
, typical feedlot husbandry of cattle requires an input of 35 kcal of fossil fuel to produce one kcal of food energy in beef, far more than that required for comparable plants.
A 2006 study at the University of Chicago
University of Chicago
The University of Chicago is a private research university in Chicago, Illinois, USA. It was founded by the American Baptist Education Society with a donation from oil magnate and philanthropist John D. Rockefeller and incorporated in 1890...
concluded that a person switching from a typical American diet to eating 20% less meat, or about 6 oz a day would prevent the emission of 1485 kg of carbon dioxide
Carbon dioxide
Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...
. The difference exceeds that of an individual switching from a Toyota Camry
Toyota Camry
The Toyota Camry is a series of mid-size automobiles manufactured by Toyota since 1982, and sold in the majority of automotive markets throughout the world...
to the hybrid Toyota Prius
Toyota Prius
The Toyota Prius is a full hybrid electric mid-size hatchback, formerly a compact sedan developed and manufactured by the Toyota Motor Corporation...
, and collectively amounts to over 6% of the total U.S. greenhouse gas
Greenhouse gas
A greenhouse gas is a gas in an atmosphere that absorbs and emits radiation within the thermal infrared range. This process is the fundamental cause of the greenhouse effect. The primary greenhouse gases in the Earth's atmosphere are water vapor, carbon dioxide, methane, nitrous oxide, and ozone...
emissions.
This view, however, reflects the situation in the developed world and does not take into account the situation in most third world countries. In the developing world, notably Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
and Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
, fossil fuels are seldom used to transport feed for farm animals. Sheep or goats, for example, require no fuel, since they graze on farmlands, while bales of hay
Hay
Hay is grass, legumes or other herbaceous plants that have been cut, dried, and stored for use as animal fodder, particularly for grazing livestock such as cattle, horses, goats, and sheep. Hay is also fed to pets such as rabbits and guinea pigs...
for bovines are still transported mainly using bullock cart
Cart
A cart is a vehicle designed for transport, using two wheels and normally pulled by one or a pair of draught animals. A handcart is pulled or pushed by one or more people...
s or similar devices. Little to no meat processing takes place in the vast majority of the developing world. Animals are also often herded to the place of slaughter (with the exception of poultry) resulting in a very low use of fossil fuels. In fact, farm animals in the developing world are used for multiple purposes, from providing draught power to transportation, while also serving as meat once they reach the end of their economic lives.
A more efficient use of animal waste may be a contributing factor in sustainability. The by-products of slaughtered animals can be used to provide biogas
Biogas
Biogas typically refers to a gas produced by the biological breakdown of organic matter in the absence of oxygen. Organic waste such as dead plant and animal material, animal dung, and kitchen waste can be converted into a gaseous fuel called biogas...
. Train
Train
A train is a connected series of vehicles for rail transport that move along a track to transport cargo or passengers from one place to another place. The track usually consists of two rails, but might also be a monorail or maglev guideway.Propulsion for the train is provided by a separate...
s running on this fuel are already in operation in Sweden
Sweden
Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
. The use of biogas to run mass transit
Public transport
Public transport is a shared passenger transportation service which is available for use by the general public, as distinct from modes such as taxicab, car pooling or hired buses which are not shared by strangers without private arrangement.Public transport modes include buses, trolleybuses, trams...
is likely only possible as a side effect of industrial agriculture
Industrial agriculture
Industrial farming is a form of modern farming that refers to the industrialized production of livestock, poultry, fish, and crops. The methods of industrial agriculture are technoscientific, economic, and political...
.
Response
The detrimental environmental effects of meat production has become a strong argument in favour of the reduction or abandonment of the consumption of meat, most notably for vegetarianismVegetarianism
Vegetarianism encompasses the practice of following plant-based diets , with or without the inclusion of dairy products or eggs, and with the exclusion of meat...
. Individual commitment is being increasingly supported by local initiatives, such as the meat-free days of the Belgian
Belgium
Belgium , officially the Kingdom of Belgium, is a federal state in Western Europe. It is a founding member of the European Union and hosts the EU's headquarters, and those of several other major international organisations such as NATO.Belgium is also a member of, or affiliated to, many...
city of Ghent
Ghent
Ghent is a city and a municipality located in the Flemish region of Belgium. It is the capital and biggest city of the East Flanders province. The city started as a settlement at the confluence of the Rivers Scheldt and Lys and in the Middle Ages became one of the largest and richest cities of...
(or Veggiedag) which imposes vegetarian-only food in public canteens for civil servants and elected concillors, soon in all schools, and promotes vegetarian eating options in town through the distribution of "veggie street maps".
The UN has admitted a report linking livestock to global warming exaggerated the impact of eating meat on climate change.
Dr Frank Mitloehner, from the University of California at Davis (UCD), said meat and milk production generates less greenhouse gas than most environmentalists claim and that the emissions figures were calculated differently to the transport figures, resulting in an “apples-and-oranges analogy that truly confused the issue”.
The meat figure had been reached by adding all greenhouse-gas emissions associated with meat production, including fertilizer production, land clearance, methane emissions and vehicle use on farms, whereas the transport figure had only included the burning of fossil fuels. In the original press release in which Dr. Mitloehner's assertions appear, it transpires that his work was funded by a $26,000 grant from the Beef Checkoff Program. In addition, his comments do not state that the UN's calculations are false, but rather that they considered the entire commodity chain, which they did not do for transport.