George Wuerthner, NewWest.net
The impact of factory farming upon the American land and native
biodiversity is seldom discussed, but animal protein production has a
significant impact upon the Nation’s land and water. The direct
environmental problems like air or water pollution associated with large
factory farming operations may be clear, but less obvious are the
environmental impacts associated with the agricultural production of feed
crops and other consequences associated with large factory farming
According to the Animal Feed Manufacturer's Association, one third of the world’s grains are fed directly to animals. In developed countries the percentage of grains fed directly to livestock rises to 60%, with 80% of the grains in the United States fed to livestock. Since the United States is the leading producer of beef cattle in the world, it is also the top animal feed producer in the world, with more than double the acreage in animal feed production than its closest rival China . This means the majority of cropland in the United States is not growing food for direct human consumption as many presume, but is used to grow forage crops for domestic livestock, including chickens, hogs, and cattle. In fact, in the United States, domestic livestock consume 5 times as much grain as the entire American population
It takes a huge amount of grain crops to support livestock production. For instance, to produce 1 kg of beef requires 7 kg of feed grain. Though chickens are more efficient at converting grain to meat, the ratio is still two to one with 2 kg of grain required to produce 1 kg of meat According to Cornell University’s David Pimentel, if the cropland currently used to grow grain fed to livestock were directed towards growing crops for human consumption, we could feed 800 million additional people or more likely provide a descent meal for those whose diet is inadequate.
In order to feed concentrated, confined animals, huge acreages of America’ s best farmland have been converted into monocultures of often genetically modified crops that stretch for miles. The major feed crops are corn, soybeans, and hay/alfalfa with smaller amounts of other grains like oats, barley and even wheat. For instance, 22% of all wheat grown in the US ultimately ends up as animal feed, rather than in food products like bread or cereal consumed directly by humans.
While it’s difficult to determine how much of any crop is used to feed confined animal operations as opposed to diverse small farming operations, the total impact of animal agriculture of any kind is significant. Consider these statistics.
Globally, production of livestock feed uses a third of the Earth’s arable land In the United States farmland production is even more skewed towards animal feed. In 2008 American farmers, primarily in the Mid-west, planted 87 million acres to feeder corn. Part of that acreage figure was due to demand for corn created by ethanol, but the bulk of the corn acreage is used for animal feed. By comparison, farmers only planted an average of 234,000 acres across the entire country to fresh market sweet corn, the plant we consume directly for corn on the cob, and other food .
To give some comparison, Montana , the fourth largest state in the Nation is 93 million acres in size. So imagine nothing but corn stretching east and west across Montana’s 550 miles and north and south by 300 miles. This is a huge area to be plowed up, and planted to an exotic grass crop that requires huge inputs of pesticides and fertilizer to sustain.
Similarly the acreage devoted to soybeans is huge. According to the USDA, some 74.5 million acres was planted to soybeans in 2008. And despite the popularity of tofu and other soy based food products, less than 2% of the soybean crop is used for production of food for direct human consumption—with most of the annual soybean crop going for animal feed.
Hay and/or alfalfa are yet another significant crop for confined livestock production, primarily dairy cows and beef cattle. In the United States, approximately 59 million acres are planted to hay/alfalfa annually . To put this in perspective, Oregon is 60 million acres in size.
Though slightly better than a row crop like corn or soybeans as wildlife habitat, hay/alfalfa fields still represent a net loss in native biodiversity and wildlife habitat. Hay/alfalfa replace native vegetation, and often require excessive amounts of fertilizers, and are cut frequently destroying even their temporal value as hiding and nesting cover for many wildlife species.
Taken together these three animal feed crops cover a minimum area over 200 million plus acres. To put these figures of animal feed cropland into perspective, the amount of land used to grow the top ten fresh vegetables in the US ( asparagus, broccoli, carrots, cauliflower, celery, head lettuce, honeydew melons onions, sweet corn, and tomatoes) occupies about a million acres.
If you fly over or drive across Iowa, Illinois, Ohio, Missouri, and other Mid-western states, you’ll pass mile after mile of corn and/or soybean fields. Growing these crops has led to the near-extirpation of native plant communities like the tall grass prairie . Less than 4% of the native tall grass prairie remains and in some states like Iowa which has less than 0.1% of its original tall grass prairie left, tall grass prairie is functionally extinct. Plus “clean” farming eliminates what little natural vegetation used to remain as woodlots, fenceline strips, wetlands, and other natural areas that in the past supported native species with the agricultural matrix.
Destruction of native plant communities has had serious impacts on native biodiversity. Agriculture, including livestock production as well as crop production combined, is the number source for species endangerment in the country , and this number would be higher if you were to add in the species that are negatively impacted by exotic species, many of which increase due to habitat modification by agricultural production.
Agriculture is also the largest user of US water resources, with confined animal operations the largest per capita consumer of water. Grain fed beef production uses 100,000 gallons of water to produce every kg of food. By comparison, a similar kg of water-hungry rice uses only 2000 gallons of water, while potatoes require a mere 500 gallons. The primary mission of most western reservoirs is water storage for irrigated agriculture. Even in California which grows the bulk of the Nation’s vegetables and fruits, the largest consumers of irrigation water in the state by acreage is irrigated hay/alfalfa production.
Thus the environmental impacts associated with these dams and reservoirs such as barriers to salmon migration salmon, changes in water flows and flooding, are one indirect cost of factory farming operations. Add to this the direct dewatering of rivers for hay and other forage crop production is the loss of ground water supplies by pumping, particularly of the Ogalla aquifer. It’s easy to see why some argue that livestock production is the leading causes of water degradation .
Agriculture also degrades water in other more direct ways. Livestock produce 130 times the waste of the entire human population of the United States, and unlike the human waste which tend to be treated in sewage plants; most animal waste winds up on the land or in the water. Not surprisingly, livestock production is the leading cause of non-point surface water pollution accounting for 72% of the pollution in rives and 56% of the pollution in lakes.
Agriculture production is also the number one source for groundwater contamination in the Nation, with 49 states reporting high nitrates and 43 states reporting pesticide production attributed to agricultural practices .
Agricultural production is the largest source for soil erosion in the United States with current rates exceeding soil production rates by 17 times with 90% of US croplands losing soils above sustainable rates Since the majority of the nation’s cropland is growing animal feed, the majority of soil erosion is a direct consequence of this production.
Another indirect consequence of factory farming is the energy used to grow and transport feed. Animal protein production uses eight times the fossil fuel energy as growing vegetables or grass fed livestock Beef production was particularly energy costly, requiring 54 times the fossil fuel equivalent of non-grain fed sources of protein.
Lest we forget, livestock are a significant contributor to global warming. The world’s livestock produces 25% of the global greenhouse gases, with the waste lagoons of factory farms contributing another 5%. And according to a UN report, the global livestock sector generates more greenhouse gas emissions measured in CO2 equivalent – 18 percent – than transport.
Much, though not all, of these environmental impacts would be reduced or avoided altogether if factory farming and other kinds of confined animal production were eliminated. A shift to smaller, diverse farms, and a reduction, if not outright elimination of meat consumption, would both contribute to a huge reduction in environmental impacts of animal agriculture.
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