Grazing
Sheep and goats were domesticated by nomads before the first permanent settlements were constructed around 7000 BC. Cattle and pigs followed somewhat later, once people started to live in fixed settlements. In America, livestock were grazed on public land from the Civil War era. The Taylor Grazing Act of 1934 was enacted after the Great Depression to regulate the use of public land for grazing purposes. These early practices enabled cattle and pigs to be kept alongside sheep and goats. People who supervise grazing livestock are called shepherds. In the vast Eurasian steppe, migrating and grazing herds of sheep and horse between different pasture regions had been the primary means of food production for the Inner Asia horseback nomads. Many nomadic empires rose and fell throughout history until the early modern period.
Farmers may employ many different strategies of grazing for optimum production. Grazing may be continuous, seasonal, or rotational within a grazing period. Longer rotations are found in ley farming, alternating arable and fodder crops. In rest rotation, deferred rotation, and mob grazing, grasses get longer time to recover or leave land fallow. Patch-burn sets up a rotation of fresh grass after burning with two years of rest. Mob grazing is a system invented in 2002 that uses very large herds on land left fallow longer than usual. Cell grazing forms a type of rotational grazing using as many small paddocks as fencing allows. Riparian area management uses fencing to keep livestock off ranges near streams or water areas until after wildlife periods. This technique balances maintenance of forage and livestock production with maintenance of biodiversity and ecosystem services.
Livestock grazing contributes to many negative effects on the environment including deforestation and extinction of native wildlife. Pollution of streams and rivers occurs alongside overgrazing and soil degradation. Desertification and ecological disturbance threaten ecosystem stability. A 2013 FAO report estimated livestock were responsible for 14.5% of anthropogenic greenhouse gas emissions. In New Zealand, methane and nitrous oxide from agriculture made up somewhat less than half of the country's greenhouse gas emissions in 2004. Grazing can also have beneficial environmental effects such as improving the soil with nutrient redistribution. Trampling aerates the soil while controlling fire increases biodiversity by removing biomass. Grazer urine and faeces recycle nitrogen, phosphorus, potassium and other plant nutrients back into the soil. These organisms aid in carbon sequestration and water filtration within the earth.
Conservation grazing proposes to use grazing animals to improve the biodiversity of a site. Due to their hardy nature, rare and native breeds are often used in conservation grazing. Cattle such as the English Longhorn and Highland provide grazing to re-establish traditional hay meadows. The Tallgrass Prairie Preserve in northeastern Oklahoma has been patch-burn grazed with bison herds for over ten years. Agrivoltaics allows solar arrays to be placed over grazing fields. More than 100,000 sheep graze at solar arrays primarily in the South United States. Organizations such as the American Solar Grazing Association promote best practices for co-locating solar energy and grazing operations. This approach reduces maintenance costs by minimizing the need for mechanical mowing. It enhances land productivity by integrating renewable energy production with agricultural use.
According to a report by the Food and Agriculture Organization, about 60% of the world's grassland is covered by grazing systems. Grazing systems supply about 9 percent of the world's production of beef and about 30 percent of the world's production of sheep and goat meat. For an estimated 100 million people in arid areas, grazing livestock is the only possible source of livelihood. A similar number of people likely rely on it in other zones. In the southwestern United States, extensive grazing of livestock has many negative impacts on local biodiversity. Livestock grazing has severely degraded riparian areas in arid climates like Arizona and New Mexico. Over 90% of the original riparian zones of these states are gone according to the Arizona state park department.
On commons in England and Wales, rights of pasture and pannage for each commoner are tightly defined by number and type of animal. The occupier of a particular cottage might be allowed to graze fifteen cattle, four horses, ponies or donkeys, and fifty geese. On some commons such as the New Forest, rights are not limited by numbers but a marking fee is paid each year. If excessive use was made of the common, a common would be stinted with limits put on the number of animals. These regulations were responsive to demographic and economic pressure rather than letting a common become degraded. During the late Medieval and early modern England, many common lands used by peasants for crop farming were enclosed and converted to pastures controlled by gentries to favor wool trades. The Taylor Grazing Act of 1934 regulated public land use after the Great Depression.
Common questions
When were sheep and goats domesticated by nomads?
Sheep and goats were domesticated by nomads before the first permanent settlements were constructed around 7000 BC. Cattle and pigs followed somewhat later, once people started to live in fixed settlements.
What is the Taylor Grazing Act of 1934?
The Taylor Grazing Act of 1934 was enacted after the Great Depression to regulate the use of public land for grazing purposes. This act regulated public land use after the Great Depression following earlier practices where livestock were grazed on public land from the Civil War era.
How much greenhouse gas emissions did livestock produce according to a 2013 FAO report?
A 2013 FAO report estimated livestock were responsible for 14.5% of anthropogenic greenhouse gas emissions. In New Zealand, methane and nitrous oxide from agriculture made up somewhat less than half of the country's greenhouse gas emissions in 2004.
Where do more than 100,000 sheep graze at solar arrays?
More than 100,000 sheep graze at solar arrays primarily in the South United States. Organizations such as the American Solar Grazing Association promote best practices for co-locating solar energy and grazing operations.
Why does overgrazing degrade riparian areas in arid climates like Arizona and New Mexico?
Livestock grazing has severely degraded riparian areas in arid climates like Arizona and New Mexico. Over 90% of the original riparian zones of these states are gone according to the Arizona state park department.