Industrial corn and soybean production are clearly linked to the problems in Lake Erie via fertilizers. But factory farming of livestock is also suspect. Concentrated animal feeding operations (CAFOs) have a manure problem. Because so many animals are confined in such as small area, they often produce far more manure than can be applied to the surrounding farmlands without causing runoff. That means more nitrogen and phosphorus gets into streams.In its research Sustainable Table has compiled the figures on the amount of US raised soy and corn which is used for animal feed and it is a stunning 47% of soy and 60% of corn produced in the US being consumed by livestock!
When livestock farms were smaller, and more dispersed geographically, manure could be used to fertilize nearby crop fields in a balanced way, but today CAFOs are large and often located near one another. And it is simply too expensive to transport manure far enough to spread onto fields in amounts that won’t end up in streams or groundwater.
Although the role of CAFOs in the Lake Erie microbial blooms has not been quantified, Ohio has many CAFOs. And the overlap between the location of most Ohio CAFOs and the Maumee River watershed, the source of most of the phosphorus that causes the blooms, is striking.
Current industrial farming practices rely heavily on grain. Under current US agriculture policy, the government provides substantial subsidies to farmers who produce grains, particularly corn and soybeans. Livestock producers often use corn and soy as a base for their animal feed because these protein-rich grains help bring animals to market weight faster, and because they are cheaper than other feed options as a result of government subsidies. It has been estimated that the operating costs of factory farms G would be 7-10% higher without these subsidies. As a result, a large percentage of grains grown in the US are used in animal feed, with 47% of soy and 60% of corn produced in the US being consumed by livestock.Sustainable Table also tackles the 'manure problem'.
The USDA estimates that more than 335 million tons of “dry matter” waste (the portion of waste remaining after water is removed) is produced annually on farms in the United States, representing almost a third of the total municipal and industrial waste produced every year. What’s more, animal feeding operations annually produce about 100 times more manure than the amount of human sewage sludge processed in US municipal wastewater plants. One dairy farm with 2,500 cows produces as much waste as a city with around 411,000 residents. Unlike human waste, however, in most cases the law does not require that livestock waste be treated.To better understand the scale of the problem, Sustainable Table compares animal and human waste production:
At farms where animals are allowed to graze on pasture, much - if not all - of their manure is excreted directly onto the land, serving as a fertilizer and recycling nutrients back into the soil. On industrial livestock farms, however, animals drop their manure in the houses where they live. From there, the manure must be cleaned out, transported, and stored, each step of which can negatively affect the environment. Simply cleaning out livestock houses can waste vast amounts of water—a dairy operation that utilizes an automatic “flushing” system can use up to 150 gallons of water per cow per day.
In order to compare the impact of different types of animals, livestock statistics are often cited in terms of “animal units.” One animal unit equals 1,000 lbs. of the live weight of an animal, (for example, four 1,250-pound cows equal 5 “animal units” of cattle, while 125 eight-pound chickens make up 1 “animal unit” of chicken).The case against industrial farming especially industrial animal farming is apparent and growing stronger every day. Global warming brings an additional element to the crisis because rising water temperate creates a fertile growing atmosphere for pollutants contributing to the safety of our drinking water sources.
By this measure, one animal unit of broiler (meat) chickens produces an average of 14.97 tons of manure each year, fattened cattle 10.59 tons per year and dairy cows 15.24 tons per year. In comparison, one “animal unit” of humans produces a mere 5.48 tons of waste per year.