Agriculture, also called farming or husbandry, is the
cultivation of animals, plants, fungi, and other life forms for food, fiber, biofuel, medicinals and other products used to sustain and enhance human life.Agriculture was the key development in the rise of sedentary
human civilization, whereby farming of domesticated
species created food surpluses
that nurtured the development of civilization.
The study of agriculture is known as agricultural science. The history of agriculture dates back thousands of years, and its development has been
driven and defined by greatly different climates,
cultures, and technologies. However, all farming generally relies on techniques
to expand and maintain the lands that are suitable for raising domesticated
species. For plants, this usually requires some form of irrigation,
although there are methods of dryland farming.
Livestock
are raised in a combination of grassland-based and landless systems, in an
industry that covers almost one-third of the world's ice- and water-free area.
In the developed world, industrial agriculture based on large-scale monoculture
has become the dominant system of modern farming, although there is growing
support for sustainable agriculture, including permaculture
and organic agriculture.
Until the Industrial Revolution, the vast majority of the human population labored in
agriculture. Pre-industrial agriculture was typically subsistence agriculture/self-sufficiency
in which farmers raised most of their crops for their own consumption instead
of cash crops
for trade. A remarkable shift in agricultural practices has occurred over the
past century in response to new technologies, and the development of world
markets. This also has led to technological improvements in agricultural
techniques, such as the Haber-Bosch
method for synthesizing ammonium nitrate
which made the traditional practice of recycling nutrients
with crop rotation and animal manure less important.
Modern agronomy, plant breeding,
agrochemicals
such as pesticides and fertilizers,
and technological improvements have sharply increased yields from cultivation,
but at the same time have caused widespread ecological damage and negative
human health effects. Selective breeding and modern practices in animal husbandry have similarly
increased the output of meat, but have raised concerns about animal welfare
and the health effects of the antibiotics,
growth hormones, and other chemicals commonly used in industrial meat
production. Genetically
modified organisms are an increasing component of
agriculture, although they are banned in several countries. Agricultural food
production and water management are increasingly becoming global issues that
are fostering debate on a number of fronts. Significant degradation of land and
water resources, including the depletion of aquifers, has been
observed in recent decades, and the effects of global warming on agriculture
and of agriculture on global warming are still not fully understood.
The major agricultural products can
be broadly grouped into foods, fibers, fuels, and raw materials.
Specific foods include cereals (grains), vegetables,
fruits, oils, meats and spices. Fibers include cotton, wool, hemp, silk and flax. Raw materials include lumber and bamboo. Other useful materials are produced by plants, such as resins, dyes, drugs, perfumes, biofuels and ornamental products such as cut flowers
and nursery plants. Over one third of the world's workers are employed in
agriculture, second only to the services' sector, although the percentages of
agricultural workers in developed countries has decreased significantly over
the past several centuries.
Etymology and terminology
The
word agriculture is a late Middle English adaptation of Latin agricultūra,
from ager, "field", and cultūra, "cultivation" or
"growing". Agriculture usually
refers to human activities, although it is also observed in certain species of ant, termite and ambrosia beetle. To practice
agriculture means to use natural resources to "produce commodities which
maintain life, including food, fiber, forest products, horticultural crops, and
their related services." This definition
includes arable
farming
or agronomy, and horticulture, all terms for the
growing of plants, animal husbandry and forestry. A distinction is
sometimes made between forestry and agriculture, based on the former's longer
management rotations, extensive versus intensive management practices and
development mainly by nature, rather than by man. Even then, it is acknowledged
that there is a large amount of knowledge transfer and overlap between silviculture (the management of
forests) and agriculture. In traditional
farming, the two are often combined even on small landholdings, leading to the
term agroforestry.
History
Agricultural
practices such as irrigation, crop rotation, application of fertilizers and pesticides, and the domestication of livestock were
developed long ago, but have made great progress in the past century. The history
of agriculture
has played a major role in human
history,
as agricultural progress has been a crucial factor in worldwide socio-economic change. Division
of labour
in agricultural societies made commonplace specializations rarely seen in hunter-gatherer cultures, which
allowed the growth of towns and cities, and the complex societies we call civilizations. When farmers became
capable of producing food beyond the needs of their own families, others in
their society were free to devote themselves to projects other than food
acquisition. Historians and anthropologists have long argued that the
development of agriculture made civilization possible. According to geographer Jared Diamond, the costs of
agriculture were: "the average daily number of work hours increased,
nutrition deteriorated, infectious disease and body wear increased, and
lifespan shortened."
Prehistoric origins
Forest
gardening,
a plant-based food production system, is thought to be the world's oldest agroecosystem. Forest gardens
originated in prehistoric times along
jungle-clad river banks and in the wet foothills of monsoon regions. In the
gradual process of a family improving their immediate environment, useful tree
and vine species were identified, protected and improved whilst undesirable
species were eliminated. Eventually superior foreign species were selected and
incorporated into the family's garden.
Neolithic
The
Fertile
Crescent
of Western
Asia
first saw the domestication of animals, starting the Neolithic Revolution.
Between 10,000 and 13,000 years ago, the ancestors of modern cattle, sheep,
goats and pigs were domesticated in this area. The gradual transition from wild
harvesting to deliberate cultivation happened independently in several areas
around the globe.Agriculture allowed
for the support of an increased population, leading to larger societies and
eventually the development of cities. It also created the need for greater
organization of political power (and the creation of social
stratification),
as decisions had to be made regarding labor and harvest allocation and access
rights to water and land. Agriculture bred immobility, as populations settled
down for long periods of time, which led to the accumulation of material goods.
Early
Neolithic villages show
evidence of the ability to process grain, and the Near East is the ancient home
of the ancestors of wheat, barley and peas. There is evidence of the cultivation
of figs in the Jordan Valley as long as 11,300 years ago, and cereal (grain) production
in Syria approximately 9,000 years ago. During the same period, farmers in
China began to farm rice and millet, using man-made
floods and fires as part of their cultivation regimen. Fiber crops were
domesticated as early as food crops, with China domesticating hemp, cotton being developed
independently in Africa and South America, and the Near East domesticating flax.The use of soil
amendments, including manure, fish, compost and ashes, appears to have begun
early, and developed independently in several areas of the world, including Mesopotamia, the Nile Valley and Eastern Asia.
Squash was grown in Mexico
nearly 10,000 years ago, while maize-like plants, derived from the wild teosinte, began to be seen at
around 9,000 years ago. The derivation of teosinte into modern corn was slow,
however, and it took until 5,500 to 6,000 years ago
to turn into what we know today as maize. It then gradually spread across North
America and was the major crop of Native Americans at the time of European
exploration. Beans were domesticated around the same
time, and together these three plants formed the Three Sisters nutritional foundation of many native
populations in North and Central America. Combined with peppers, these crops
provided a balanced diet for much of the continent. Grapes were first grown for
wine approximately 8,000
years ago, in the Southern Caucasus, and by 3000 BC had
spread to the Fertile Crescent, the Jordan Valley and Egypt.
Agriculture
advanced to Europe slightly later, reaching the northeast of the continent from
the east around 4000 BC. The idea that agriculture spread to Europe, rather
than independently developing there, has led to two main hypotheses. The first
is a "wave of advance", which holds that agriculture traveled slowly
and steadily across the continent, while the second, "population
pulse" theory, holds that it moved in jumps. Also around 6000
years ago, horses first began to be domesticated in the Eurasian steppes. Initially used for
food, it was quickly discovered that they were useful for field work and
carrying goods and people. Around 5,000 years
ago, sunflowers were first cultivated
in North America, while South America's Andes region was developing the potato. A minor center of
domestication, the indigenous peoples of the eastern United States appear to
have domesticated numerous crops, including tobacco.
Bronze and Iron Ages
Beginning
around 3000 BC, nomadic pastoralism, with societies
focused on the care of livestock for subsistence, appeared independently in
several areas in Europe and Asia. The main region was the steppes stretching from the Hungarian Plain to Manchuria, where cattle,
sheep, horses, and to a lesser extent yaks and bactrian camels provided sustenance.
The second was in Arabia, where one-humped camels were the main
animal, with sheep, goats and horses also seen. The third area was a band of
societies in areas of eastern and central Africa with a tropical savannah climate. Cattle and
goats were found most often in this area, with smaller numbers of sheep, horses
and camels. A fourth area, more minor than the others, was found in northern Europe
and Asia and was focused on reindeer herding.
Between
2500 and 2000 BC, the simplest form of the plough, called the ard, spread throughout
Europe, replacing the hoe. This change in
equipment significantly increased cultivation ability, and affected the demand
for land, as well as ideas about property, inheritance and family rights. Before this period,
simple digging
sticks
or hoes were used. These tools would have also been easier to transport, which
was a benefit as people only stayed until the soil's nutrients were depleted.
However, as the continuous cultivating of smaller pieces of land became a
sustaining practice throughout the world, ards were much more efficient than
digging sticks. As humanity became
more stationary, empires, such as the New
Kingdom of Egypt
and the Ancient
Romans,
arose, dependent upon agriculture to feed their growing populations, and
slavery, which was used to provide the labor needed for continually
intensifying agricultural processes. Agricultural technology continued to
improve, allowing the expansion of available crop varieties, including a wide
range of fruits, vegetables, oil crops, spices and other products. China was also an
important center for agricultural technology development during this period.
During the Zhou
dynasty
(1666–221 BC), the first canals were built, and irrigation was used
extensively. The later Three Kingdoms and Northern and Southern dynasties (221–581 AD) brought
the first biological pest control, extensive writings on agricultural topics
and technological innovations such as steel and the wheelbarrow.
In
the ancient world, fresh products, such as meats, dairy products and fresh
fruits and vegetables, were likely consumed relatively close to where they were
produced. Less perishable products, such as grains, preserved foods, olive oil
and wine, were often traded over an extensive network of land and sea routes.
The ancient trade in agricultural goods was well established, with wine traded
in the Mediterranean region in the 6th century BC and Rome receiving extensive
shipments of grain as tax payments by the 2nd century BC. Huge amounts of grain
were transported, mainly by sea, and it was during this period that the
subsidization of grain farming began, for the prevention of famine. Ancient
Rome was a major center for agricultural trade. Trade routes stretched from
Britain and Scandinavia in the west to India and China in the east, and
included major crops, such as grain, wine and olive oil (also a fuel for oil lamps), as well as
additional products, including spices, fabrics and drugs.
In
Ancient
Greece
and Rome, many scholars
documented farming techniques, including the use of fertilizers.Much of what was
believed about farming and plant nutrition at this time was later found to be incorrect,
but their theories provided the scientific foundation for the development of
agricultural theories through the Middle Ages. Ideas about soil
fertility and fertilization remained much the same from the time of Greco-Roman
scholars until the 19th century, with correspondingly low crop yields. By the time of Alexander
the Great's
conquests (330–323 BC), the role of horses had developed, and they played a
huge role in warfare and agriculture. Innovations continued to be developed
which allowed them to work longer, harder and more efficiently. By medieval
times they became the primary source of power for agriculture, transport and
warfare, a position they held until the development of the steam and internal
combustion
engines. The Mayan culture developed
several innovations in agriculture during its peak, which ranged from 400 BC to
900 AD and was heavily dependent upon agriculture to support its population.
The Mayans used extensive canal and raised field systems to farm the large
portions of swampland on the Yucatán
Peninsula.
Middle Ages
The
Middle Ages saw significant improvements in the agricultural techniques and
technology. During this time period, monasteries spread throughout Europe and
became important centers for the collection of knowledge related to agriculture
and forestry. The manorial
system,
which existed under different names throughout Europe and Asia, allowed large
landowners significant control over both their land and its laborers, in the
form of peasants or serfs. During the medieval
period, the Arab
world
was critical in the exchange of crops and technology between the European, Asia
and African continents. Besides transporting numerous crops, they introduced
the concept of summer irrigation to Europe and developed the beginnings of the plantation system of sugarcane growing through the
use of slaves for intensive cultivation. Population continued
to increase along with land use. From 100 BC to 1600 AD, methane emissions, produced
by domesticated animals and rice growing, increased substantially.
By
900 AD in Europe, developments in iron smelting allowed for
increased production, leading to developments in the production of agricultural
implements such as ploughs, hand tools and horse shoes. The plough was
significantly improved, developing into the mouldboard
plough,
capable of turning over the heavy, wet soils of northern Europe. This led to
the clearing of forests in that area and a significant increase in agricultural
production, which in turn led to an increase in population. A similar plough,
which may have developed independently, was also found in China as early as the
9th century. At the same time,
farmers in Europe moved from a two field crop rotation to a three field
crop rotation in which one field of three was left fallow every year. This
resulted in increased productivity and nutrition, as the change in rotations
led to different crops being planted, including legumes such as peas,
lentils and beans. Inventions such as improved horse harnesses and the whippletree also changed methods
of cultivation. Watermills were initially
developed by the Romans, but were improved throughout the Middle Ages, along
with windmills, and used to grind
grains into flour, cut wood and process flax and wool, among other uses.
Crops
included wheat, rye, barley and oats. Peas, beans, and vetches became common from
the 13th century onward as a fodder crop for animals and also
for their nitrogen-fixation fertilizing
properties. Crop yields peaked in the 13th century, and stayed more or less
steady until the 18th century. Though the
limitations of medieval farming were once thought to have provided a ceiling
for the population growth in the Middle Ages, recent studies have shown that the
technology of medieval agriculture was always sufficient for the needs of the
people under normal circumstances, and that it was only during exceptionally
harsh times, such as the terrible weather of 1315–17, that the needs of
the population could not be met. The Medieval
Warm Period,
between 900–1300 AD, brought generally warmer global temperatures, leading to
increased harvests throughout Europe and a greater northern range for
subtropical crops such as figs and olives. Greenland and Iceland were settled by
Europeans during this period, and supported agricultural activities. The
long-term warming period is generally thought to have occurred mainly in
Europe, but other areas of the world experienced shorter warming periods at
different times during this period, including China in the 11th and 12th
centuries, with similar effects on agriculture. The climate variations found in
Europe during the Medieval Warm Period returned to more moderate levels in the
15th century, and terminated in the Little Ice Age of the 16th-mid 19th
centuries.
Global exchange
After
1492, a global
exchange
of previously local crops and livestock breeds occurred. Key crops involved in
this exchange included maize, potatoes, sweet potatoes and manioc traveling from the
New World to the Old, and several varieties of wheat, barley, rice and turnips going from the Old
World to the New. There were very few livestock species in the New World, with
horses, cattle, sheep and goats being completely unknown before their arrival
with Old World settlers. Crops moving in both directions across the Atlantic Ocean caused population
growth around the world, and had a lasting effect on many cultures.
After
its introduction from South America to Spain in the late 1500s, the potato
became an important staple crop throughout Europe by the late 1700s. The potato
allowed farmers to produce more food, and initially added variety to the
European diet. The nutrition boost caused by increased potato consumption
resulted in lower disease rates, higher birth rates and lower mortality rates,
causing a population boom throughout the British Empire, the US and Europe. The introduction of
the potato also brought about the first intensive use of fertilizer, in the
form of guano imported to Europe
from Peru, and the first artificial pesticide, in the form of an arsenic compound used to
fight Colorado
potato beetles.
Before the adoption of the potato as a major crop, the dependence on grain
caused repetitive regional and national famines when the crops
failed: 17 major famines in England alone between 1523 and 1623. Although
initially almost eliminating the danger of famine, the resulting dependence on
the potato eventually caused the European
Potato Failure,
a disastrous crop failure from disease resulting in
widespread famine, and the death of over one million people in Ireland alone.
Modern developments
The
British Agricultural Revolution, with its massive increases in agricultural
productivity and net output, is a topic of ongoing debate among historians and
agricultural scholars. The changes in agriculture in Britain between the 16th
and 19th centuries would subsequently affect agriculture around the world.
Major points of development included enclosure, mechanization, crop rotation and selective
breeding.
Prior to the 1960s, historians viewed the British Agricultural Revolution of
having been "largely facilitated by a small number of key
innovators," including Robert Bakewell, Thomas Coke and Charles Townshend. However, modern
historians disperse much of the importance surrounding these individual men,
and instead point to them holding a smaller position within a major societal
shift regarding agriculture in Britain.
The
agricultural changes, along with industrialization and migration, allowed the
population of Britain, as well as other countries who followed its model, such
as the US, Germany and Belgium, to escape from the Malthusian trap and increase both
their population and their standard
of living.
It is estimated that the productivity of wheat in England went up from about 19
bushels per acre in 1720 to 21–22 bushels by the middle of the century and
finally stabilized at around 30 bushels by 1840.
Premodern
agriculture across Europe was characterized by
the feudal open field system, where farmers
worked on strips of land in fields that were held in common; this was
inefficient and reduced the incentive to improve productivity. Many farms began to
be enclosed by yeomen who improved the use
of their land. This process of land reform accelerated in the
18th century with special acts of Parliament to expedite the
legal process. The consolidation of
large, privately owned holdings, encouraged the improvement of productivity
through experimentation by enterprising landowners. By the 1750s, the market
for agriculture was substantially commercialized - crop surpluses were routinely
sold by the producers on the market or exported elsewhere.
These
social changes were coupled with technical improvements. New methods of crop
rotation and land use resulted in large additions to the amount of arable land. The four-field crop rotation was popularized by Charles Townshend in the 18th century.
The system (wheat, turnips, barley and clover), opened up a fodder
crop and grazing crop allowing livestock to be bred
year-round. Yields of cereal crops increased as
farmers utilized nitrogen-rich manure and nitrogen fixing-crops such as clover, increasing the
available nitrogen in the soil and removing the limiting factor on cereal
productions that had existed prior to the early 19th century. This improved
production per farmer led to an increase in population and in the available
workforce, creating the labor force needed for the Industrial
Revolution.
The
development of agriculture into its modern form was made possible through a
continuing process of mechanization. Prior to this, basic
agricultural tools had slowly been improved over centuries of use. The plough,
for example, was a heavy implement with wheels in the 1500s. By the 1600s it
was lighter, and by 1730, the Rotherham
plough
dramatically changed farming with no wheels, interchangeable
parts,
stronger construction and less weight. During the early 1800s, cast iron replaced wood for
many parts, leading to longer-lasting implements. Seed drills had been under
development since the early 1500s, but it was Jethro Tull's 1731 invention of a horse-drawn seed
drill and horse hoe (a small plough to hoe between crop rows) that would
eventually revolutionize planting in Britain, although they would not become
popular until the early 1800s.Andrew Meikle patented the first
practical threshing
machine
in 1784.
The
Industrial
Revolution
caused a boom in international trade and shipping. Increased production caused
a rise in the need for raw materials, with European merchants purchasing the
majority of the goods. The value of goods traded worldwide increased by five
times between 1750 and 1914, with annual shipping tonnages increasing from 4
million to 30 million tons between 1800 and 1900. In the second half of the
19th century, trade also expanded in the food (including grain and meat) and wool
markets, and England (with the repeal of the Corn Laws in 1846) began to
trade quantities of industrial products for wheat from around the world. The
vast expansion of railroads that followed the
invention of the steam
engine
further revolutionized world trade, especially in the Americas and East Asia,
as goods could now be more easily traded across vast land distances. The developments of heat processing and refrigeration in the 19th century
led to a similar revolution in the meat industry, as they allowed meat to be
shipped long distances without spoiling. Countries in tropical locations, such
as Australia and South America, were at the forefront of this effort.
In
the mid-1800s, horse drawn machinery, such as the McCormick reaper, revolutionized
harvesting, while inventions such as the cotton gin made possible the
processing of large amounts of crops. During this same period, farmers began to
use steam-powered threshers and tractors, although they were
found to be expensive, dangerous and a fire hazard. The first gasoline-powered tractors were
successfully developed around 1900, and in 1923, the International
Harvester
Farmall tractor became the
first all-purpose tractor, and marked a major point in the replacement of draft
animals (particularly horses) with machines. Since that time, self-propelled
mechanical harvesters (combines), planters,
transplanters and other equipment have been developed, further revolutionizing
agriculture. These inventions
allowed farming tasks to be done with a speed and on a scale previously
impossible, leading modern farms to output much greater volumes of high-quality
produce per land unit.
The
scientific investigation of fertilization began at the Rothamsted Experimental Station in 1843 by John Bennet Lawes. He developed the
first commercial process for fertilizer production - the obtaining of phosphate from the dissolution
of coprolites in sulphuric acid. In 1909 the
revolutionary Haber-Bosch method to synthesize
ammonium
nitrate
was first demonstrated; it represented a major breakthrough and allowed crop yields to overcome previous
constraints. In the years after World War II, the use of
synthetic fertilizer increased rapidly, in sync with the increasing world
population.
Recent
Despite
the tremendous gains in agricultural productivity, famines continued to sweep
the globe through the 20th century. Through the effects of climactic events,
government policy, war and crop failure, millions of people died in each of at
least ten famines between the 1920s and the 1990s.
The
Green Revolution refers to a series of research, development, and technology
transfer
initiatives, occurring between the 1940s and the late 1970s, that increased
agriculture production around the world, beginning most markedly in the late
1960s. It involved the development of high-yielding varieties of cereal grains,
expansion of irrigation infrastructure, modernization of management techniques,
distribution of hybridized seeds, synthetic fertilizers, and pesticides to farmers. The initiatives, led
by Norman
Borlaug,
the "Father of the Green Revolution", are credited with saving
hundreds of millions of people from starvation. Demographer Thomas Malthus in 1798 famously
predicted that the Earth would not be able to support its growing population,
but technologies such as those promoted by the Green Revolution have thus far
allowed the world to produce a surplus of food.
Although
the Green Revolution significantly increased rice yields in Asia, yield
increases have not occurred in the past 15–20 years. The genetic "yield
potential" has increased for wheat, but the yield potential for rice has
not increased since 1966, and the yield potential for maize has "barely
increased in 35 years". It takes a decade or
two for herbicide-resistant weeds to emerge, and insects become resistant to
insecticides within about a decade. Crop rotation helps to prevent resistances.
The
cereals rice, corn, and wheat provide 60% of human food supply. Between 1700 and
1980, "the total area of cultivated land worldwide increased 466%"
and yields increased dramatically, particularly because of selectively
bred
high-yielding varieties, fertilizers, pesticides, irrigation, and machinery. However, concerns
have been raised over the sustainability of intensive
agriculture. Intensive agriculture has become associated with decreased soil quality in India and Asia,
and there has been increased concern over the effects of fertilizers and
pesticides on the environment, particularly as population increases and food
demand expands. The monocultures typically used in
intensive agriculture increase the number of pests, which are controlled
through pesticides. Integrated pest management (IPM), which "has been promoted
for decades and has had some notable successes" has not significantly
affected the use of pesticides because policies encourage the use of pesticides
and IPM is knowledge-intensive. In the 21st century,
plants have been used to grow biofuels, pharmaceuticals (including biopharmaceuticals), and bioplastics.
Contemporary agriculture
In
the past century agriculture has been characterized by increased productivity,
the substitution of synthetic fertilizers and pesticides for labor, water pollution, and farm subsidies. In recent years
there has been a backlash against the external environmental
effects
of conventional agriculture, resulting in the organic and sustainable
agriculture
movements. One of the major
forces behind this movement has been the European Union, which first
certified organic
food
in 1991 and began reform of its Common Agricultural Policy (CAP) in 2005 to phase out
commodity-linked farm subsidies, also known as decoupling. The growth of organic farming has
renewed research in alternative technologies such as integrated pest management and selective breeding. Recent
mainstream technological developments include genetically modified food.
In
2007, higher incentives for farmers to grow non-food biofuel crops combined with other
factors, such as overdevelopment of former farm lands, rising transportation
costs, climate
change,
growing consumer demand in China and India, and population growth, caused food shortages in Asia, the Middle
East, Africa, and Mexico, as well as rising food prices around the globe. As of December 2007,
37 countries faced food crises, and 20 had imposed some sort of food-price
controls. Some of these shortages resulted in food riots and even deadly
stampedes and that
an increase in smallholder
agriculture
may be part of the solution to concerns about food prices and overall food
security. They in part base this on the experience of Vietnam, which went from
a food importer to large food exporter and saw a significant drop in poverty,
due mainly to the development of smallholder agriculture in the country.
Disease
and land degradation are two of the major concerns in agriculture today. For
example, an epidemic of stem
rust
on wheat caused by the Ug99 lineage is currently
spreading across Africa and into Asia and is causing major concerns due to crop
losses of 70% or more under some conditions. Approximately 40% of
the world's agricultural land is seriously degraded. In Africa, if
current trends of soil degradation continue, the continent might be able to
feed just 25% of its population by 2025, according to UNU's Ghana-based Institute for Natural Resources in Africa.
In
2009, the agricultural
output of China
was the largest in the world, followed by the European Union, India and the
United States, according to the International Monetary Fund (see
below).
Economists measure the total factor productivity of agriculture and by this measure
agriculture in the United States is roughly 1.7 times more productive than it
was in 1948.
Workforce
As
of 2011, the International Labour Organization states that
approximately one billion people, or over 1/3 of the available work force, are
employed in the global agricultural sector. Agriculture constitutes
approximately 70% of the global employment of children, and in many countries
employs the largest percentage of women of any industry. The service sector only overtook the
agricultural sector as the largest global employer in 2007. Between 1997 and
2007, the percentage of people employed in agriculture fell by over four
percentage points, a trend that is expected to continue. The number of people
employed in agriculture varies widely on a per-country basis, ranging from less
than 2% in countries like the US and Canada to over 80% in many African
nations. In developed
countries, these figures are significantly lower than in previous centuries.
During the 16th century in Europe, for example, between 55 and 75 percent of
the population was engaged in agriculture, depending on the country. By the
19th century in Europe, this had dropped to between 35 and 65 percent.In the same
countries today, the figure is less than 10%.
Safety
Agriculture
remains a hazardous industry, and farmers worldwide remain at high risk of
work-related injuries, lung disease, noise-induced hearing loss, skin diseases, as well as certain
cancers related to chemical use and prolonged sun exposure. On industrialized
farms,
injuries frequently involve the use of agricultural
machinery,
and a common cause of fatal agricultural injuries in developed countries is
tractor rollovers. Pesticides and other
chemicals used in farming can also be hazardous to worker health, and workers
exposed to pesticides may experience illness or have children with birth
defects.As an industry in
which families commonly share in work and live on the farm itself, entire
families can be at risk for injuries, illness, and death. Common causes of
fatal injuries among young farm workers include drowning, machinery and motor
vehicle-related accidents.
The
International Labour Organization considers agriculture "one of the most
hazardous of all economic sectors." It estimates that
the annual work-related death toll among agricultural employees is at least
170,000, twice the average rate of other jobs. In addition, incidences of
death, injury and illness related to agricultural activities often go
unreported. The organization has
developed the Safety and Health in
Agriculture Convention, 2001, which covers the range of risks in
the agriculture occupation, the prevention of these risks and the role that
individuals and organizations engaged in agriculture should play.
Agricultural production systems
Crop cultivation systems
Cropping
systems vary among farms depending on the available resources and constraints;
geography and climate of the farm; government policy; economic, social and
political pressures; and the philosophy and culture of the farmer.
Shifting
cultivation
(or slash
and burn)
is a system in which forests are burnt, releasing nutrients to support
cultivation of annual and then perennial crops for a period
of several years. Then the plot is
left fallow to regrow forest, and the farmer moves to a new plot, returning
after many more years (10–20). This fallow period is shortened if population
density grows, requiring the input of nutrients (fertilizer or manure) and some manual pest control. Annual cultivation
is the next phase of intensity in which there is no fallow period. This
requires even greater nutrient and pest control inputs.
Further
industrialization led to the use of monocultures, when one cultivar is planted on a
large acreage. Because of the low biodiversity, nutrient use is
uniform and pests tend to build up, necessitating the greater use of pesticides and fertilizers. Multiple cropping,
in which several crops are grown sequentially in one year, and intercropping, when several crops
are grown at the same time, are other kinds of annual cropping systems known as
polycultures.
In
subtropical and arid environments, the timing and extent of
agriculture may be limited by rainfall, either not allowing multiple annual crops
in a year, or requiring irrigation. In all of these
environments perennial crops are grown (coffee, chocolate) and systems are
practiced such as agroforestry. In temperate environments, where
ecosystems were predominantly grassland or prairie, highly productive
annual cropping is the dominant farming system.
Crop statistics
Important
categories of crops include cereals and pseudocereals, pulses (legumes),
forage, and fruits and vegetables. Specific crops are cultivated in distinct growing regions throughout the
world. In millions of metric tons, based on FAO estimate.
Top agricultural products, by crop
types
(million tonnes) 2004 data |
|
Cereals
|
2,263
|
Vegetables
and melons
|
866
|
715
|
|
Milk
|
619
|
Fruit
|
503
|
Meat
|
259
|
133
|
|
Fish
(2001 estimate)
|
130
|
63
|
|
60
|
|
30
|
|
Top agricultural products, by
individual crops
(million tonnes) 2011 data |
|
Sugar
cane
|
1794
|
Maize
|
883
|
Rice
|
722
|
Wheat
|
704
|
Potatoes
|
374
|
Sugar
beet
|
271
|
Soybeans
|
260
|
Cassava
|
252
|
Tomatoes
|
159
|
Barley
|
134
|
Livestock production systems
Animals,
including horses, mules, oxen, water buffalo, camels, llamas, alpacas, donkeys, and dogs, are often
used to help cultivate fields, harvest crops, wrangle other
animals, and transport farm products to buyers. Animal husbandry not only refers to
the breeding and raising of animals for meat or to harvest animal products
(like milk, eggs, or wool) on a continual basis, but also to the
breeding and care of species for work and companionship.
Livestock
production systems can be defined based on feed source, as grassland-based, mixed, and
landless. As of 2010, 30% of
Earth's ice- and water-free area was used for producing livestock, with the
sector employing approximately 1.3 billion people. Between the 1960s and the
2000s, there was a significant increase in livestock production, both by numbers
and by carcass weight, especially among beef, pigs and chickens, the latter of
which had production increased by almost a factor of 10. Non-meat animals, such
as milk cows and egg-producing chickens, also showed significant production
increases. Global cattle, sheep and goat populations are expected to continue
to increase sharply through 2050. Aquaculture or fish farming, the
production of fish for human consumption in confined operations, is one of the
fastest growing sectors of food production, growing at an average of 9% a year
between 1975 and 2007.
During
the second half of the 20th century, producers using selective
breeding
focused on creating livestock breeds and crossbreeds that increased
production, while mostly disregarding the need to preserve genetic diversity. This trend has led
to a significant decrease in genetic diversity and resources among livestock
breeds, leading to a corresponding decrease in disease resistance and local
adaptations previously found among traditional breeds.
Grassland
based livestock production relies upon plant material such as shrubland, rangeland, and pastures for feeding ruminant animals. Outside
nutrient inputs may be used, however manure is returned directly to the
grassland as a major nutrient source. This system is particularly important in
areas where crop production is not feasible because of climate or soil,
representing 30–40 million pastoralists. Mixed production
systems use grassland, fodder crops and grain feed
crops as feed for ruminant and monogastric (one stomach; mainly chickens and
pigs) livestock. Manure is typically recycled in mixed systems as a fertilizer
for crops.
Landless
systems rely upon feed from outside the farm, representing the de-linking of
crop and livestock production found more prevalently in Organisation for
Economic Co-operation and Development(OECD) member countries. Synthetic
fertilizers are more heavily relied upon for crop production and manure
utilization becomes a challenge as well as a source for pollution. Industrialized
countries use these operations to produce much of the global supplies of
poultry and pork. Scientists estimate that 75% of the growth in livestock
production between 2003 and 2030 will be in confined animal feeding operations, sometimes called factory farming. Much of this growth
is happening in developing countries in Asia, with much smaller amounts of
growth in Africa. Some of the
practices used in commercial livestock production, including the usage of growth hormones, are controversial.
Production practices
Tillage is the practice of
plowing soil to prepare for planting or for nutrient incorporation or for pest
control. Tillage varies in intensity from conventional to no-till. It may improve
productivity by warming the soil, incorporating fertilizer and controlling
weeds, but also renders soil more prone to erosion, triggers the decomposition
of organic matter releasing CO2, and reduces the abundance and
diversity of soil organisms.
Pest
control
includes the management of weeds, insects, mites, and diseases. Chemical (pesticides), biological (biocontrol), mechanical
(tillage), and cultural practices are used. Cultural practices include crop rotation, culling, cover crops, intercropping, composting, avoidance, and resistance. Integrated pest management attempts to use all of these methods
to keep pest populations below the number which would cause economic loss, and
recommends pesticides as a last resort.
Nutrient
management
includes both the source of nutrient inputs for crop and livestock production,
and the method of utilization of manure produced by
livestock. Nutrient inputs can be chemical inorganic fertilizers, manure, green manure, compost and mined minerals.Crop nutrient use
may also be managed using cultural techniques such as crop rotation or a fallow period. Manure is used
either by holding livestock where the feed crop is growing, such as in managed intensive rotational grazing, or by spreading either dry or liquid
formulations of manure on cropland or pastures.
Water
management
is needed where rainfall is insufficient or variable, which occurs to some
degree in most regions of the world. Some farmers use irrigation to supplement
rainfall. In other areas such as the Great Plains in the U.S. and
Canada, farmers use a fallow year to conserve
soil moisture to use for growing a crop in the following year. Agriculture
represents 70% of freshwater use worldwide.
Crop alteration and biotechnology
Crop
alteration has been practiced by humankind for thousands of years, since the
beginning of civilization. Altering crops through breeding practices changes
the genetic make-up of a plant to develop crops with more beneficial
characteristics for humans, for example, larger fruits or seeds,
drought-tolerance, or resistance to pests. Significant advances in plant
breeding ensued after the work of geneticist Gregor Mendel. His work on dominant and recessive alleles, although initially
largely ignored for almost 50 years, gave plant breeders a better understanding
of genetics and breeding techniques. Crop breeding includes techniques such as
plant selection with desirable traits, self-pollination and cross-pollination, and molecular
techniques that genetically modify the organism.
Domestication
of plants has, over the centuries increased yield, improved disease resistance and drought tolerance, eased harvest and
improved the taste and nutritional value of crop plants. Careful selection and
breeding have had enormous effects on the characteristics of crop plants. Plant
selection and breeding in the 1920s and 1930s improved pasture (grasses and
clover) in New
Zealand.
Extensive X-ray and ultraviolet induced mutagenesis efforts (i.e. primitive
genetic engineering) during the 1950s produced the modern commercial varieties
of grains such as wheat, corn (maize) and barley.
The
Green
Revolution
popularized the use of conventional hybridization to sharply increase
yield by creating "high-yielding varieties". For example, average
yields of corn (maize) in the USA have increased from around 2.5 tons per
hectare (t/ha) (40 bushels per acre) in 1900 to about 9.4 t/ha (150 bushels per
acre) in 2001. Similarly, worldwide average wheat yields have increased from
less than 1 t/ha in 1900 to more than 2.5 t/ha in 1990. South American average
wheat yields are around 2 t/ha, African under 1 t/ha, and Egypt and Arabia up
to 3.5 to 4 t/ha with irrigation. In contrast, the average wheat yield in
countries such as France is over 8 t/ha. Variations in yields are due mainly to
variation in climate, genetics, and the level of intensive farming techniques (use
of fertilizers, chemical pest control, growth control to
avoid lodging).
Genetic engineering
Genetically Modified Organisms (GMO) are organisms whose genetic material has been
altered by genetic engineering techniques generally known as recombinant DNA technology. Genetic engineering has expanded the
genes available to breeders to utilize in creating desired germlines for new
crops. Increased durability, nutritional content, insect and virus resistance
and herbicide tolerance are a few of the attributes bred into crops through
genetic engineering. For some, GMO crops
cause food
safety
and food labeling concerns. Numerous countries have
placed restrictions on the production, import and/or use of GMO foods and
crops, which have been put in place due to concerns over potential health
issues, declining agricultural diversity and contamination of non-GMO crops.Currently a global
treaty, the Biosafety
Protocol,
regulates the trade of GMOs. There is ongoing discussion regarding the labeling
of foods made from GMOs, and while the EU currently requires all GMO foods to
be labeled, the US does not.
Herbicide-resistant
seed has a gene implanted into its genome that allows the plants to tolerate
exposure to herbicides, including glyphosates. These seeds allow
the farmer to grow a crop that can be sprayed with herbicides to control weeds
without harming the resistant crop. Herbicide-tolerant crops are used by
farmers worldwide. With the increasing
use of herbicide-tolerant crops, comes an increase in the use of
glyphosate-based herbicide sprays. In some areas glyphosate resistant weeds
have developed, causing farmers to switch to other herbicides. Some studies also
link widespread glyphosate usage to iron deficiencies in some crops, which is
both a crop production and a nutritional quality concern, with potential
economic and health implications.
Other
GMO crops used by growers include insect-resistant crops, which have a gene
from the soil bacterium Bacillus thuringiensis (Bt), which produces a toxin specific
to insects. These crops protect plants from damage by insects. Some believe that
similar or better pest-resistance traits can be acquired through traditional
breeding practices, and resistance to various pests can be gained through
hybridization or cross-pollination with wild species. In some cases, wild
species are the primary source of resistance traits; some tomato cultivars that
have gained resistance to at least 19 diseases did so through crossing with
wild populations of tomatoes.
Environmental impact
Agriculture
imposes external
costs
upon society through pesticides, nutrient runoff, excessive water usage, loss
of natural environment and assorted other problems. A 2000 assessment of
agriculture in the UK determined total external costs for 1996 of £2,343
million, or £208 per hectare. A 2005 analysis of
these costs in the USA concluded that cropland imposes approximately $5 to 16
billion ($30 to $96 per hectare), while livestock production imposes $714
million. Both studies, which
focused solely on the fiscal impacts, concluded that more should be done to
internalize external costs. Neither included subsidies in their analysis, but
they noted that subsidies also influence the cost of agriculture to society. In 2010, a report was published assessing the
environmental impacts of consumption and production. The study found that
agriculture and food consumption are two of the most important drivers of
environmental pressures, particularly habitat change, climate change, water use
and toxic emissions.
Livestock issues
A
senior UN official and co-author of a UN report detailing this problem, Henning
Steinfeld, said "Livestock are one of the most significant contributors to
today's most serious environmental problems". Livestock production
occupies 70% of all land used for agriculture, or 30% of the land surface of
the planet. It is one of the largest sources of greenhouse gases, responsible for 18%
of the world's greenhouse gas emissions as measured in CO2
equivalents. By comparison, all transportation emits 13.5% of the CO2.
It produces 65% of human-related nitrous oxide (which has 296 times
the global warming potential of CO2,) and 37% of all human-induced methane (which is 23 times
as warming as CO2.) It also generates 64% of the ammonia emission. Livestock
expansion is cited as a key factor driving deforestation; in the Amazon basin
70% of previously forested area is now occupied by
pastures and the remainder used for feedcrops. Through
deforestation and land
degradation,
livestock is also driving reductions in biodiversity.
Land and water issues
Land
transformation, the use of land to yield goods and services, is the most
substantial way humans alter the Earth's ecosystems, and is considered the
driving force in the loss of biodiversity. Estimates of the amount of land
transformed by humans vary from 39 to 50%.Land degradation,
the long-term decline in ecosystem function and productivity, is estimated to
be occurring on 24% of land worldwide, with cropland overrepresented. The UN-FAO report
cites land management as the driving factor behind degradation and reports that
1.5 billion people rely upon the degrading land. Degradation can be
deforestation, desertification, soil erosion, mineral depletion,
or chemical degradation (acidification and salinization).
Eutrophication, excessive nutrients
in aquatic
ecosystems
resulting in algal
blooms
and anoxia, leads to fish kills, loss of
biodiversity, and renders water unfit for drinking and other industrial uses.
Excessive fertilization and manure application to cropland, as well as high
livestock stocking densities cause nutrient (mainly nitrogen and phosphorus) runoff and leaching from agricultural
land. These nutrients are major nonpoint pollutants contributing to eutrophication of
aquatic ecosystems.
Agriculture
accounts for 70% of withdrawals of freshwater resources. Agriculture is a
major draw on water from aquifers, and currently draws
from those underground water sources at an unsustainable rate. It is long known
that aquifers in areas as diverse as northern China, the Upper Ganges and the western US
are being depleted, and new research extends these problems to aquifers in
Iran, Mexico and Saudi Arabia.Increasing pressure
is being placed on water resources by industry and urban areas, meaning that water scarcity is increasing and
agriculture is facing the challenge of producing more food for the world's
growing population with reduced water resources. Agricultural water
usage can also cause major environmental problems, including the destruction of
natural wetlands, the spread of water-borne diseases, and land degradation
through salinization and waterlogging, when irrigation is performed
incorrectly.
Pesticides
Pesticide
use has increased since 1950 to 2.5 million tons annually worldwide, yet crop
loss from pests has remained relatively constant. The World Health
Organization estimated in 1992 that 3 million pesticide poisonings occur
annually, causing 220,000 deaths. Pesticides select
for pesticide
resistance
in the pest population, leading to a condition termed the 'pesticide treadmill'
in which pest resistance warrants the development of a new pesticide.
An
alternative argument is that the way to 'save the environment' and prevent
famine is by using pesticides and intensive high yield farming, a view
exemplified by a quote heading the Center for Global Food Issues website:
'Growing more per acre leaves more land for nature'. However, critics
argue that a trade-off between the environment and a need for food is not
inevitable, and that pesticides
simply replace good agronomic practices such as crop rotation.
Climate change
Climate
change
has the potential to affect agriculture through changes in temperature,
rainfall (timing and quantity), CO2, solar radiation and the interaction
of these elements. Extreme events, such
as droughts and floods, are forecast to increase as climate change takes hold. Agriculture is among
sectors most vulnerable to the impacts of climate change; water supply for
example, will be critical to sustain agricultural production and provide the
increase in food output required to sustain the world's growing population.
Fluctuations in the flow of rivers are likely to increase in the twenty-first
century. Based on the experience of countries in the Nile river basin
(Ethiopia, Kenya and Sudan) and other developing countries, depletion of water
resources during seasons crucial for agriculture can lead to a decline in yield
by up to 50%. Transformational
approaches will be needed to manage natural resources in the future. For example,
policies, practices and tools promoting climate-smart agriculture will be
important, as will better use of scientific information on climate for
assessing risks and vulnerability. Planners and policy-makers will need to help
create suitable policies that encourage funding for such agricultural
transformation.
Agriculture
can both mitigate or worsen global warming. Some of the
increase in CO2 in the atmosphere comes from the decomposition of organic matter in the soil, and
much of the methane emitted into the atmosphere is caused by the decomposition
of organic matter in wet soils such as rice paddies, as well as the
normal digestive activities of farm animals. Further, wet or anaerobic soils also lose
nitrogen through denitrification, releasing the
greenhouse gases nitric
oxide
and nitrous oxide. Changes in
management can reduce the release of these greenhouse gases, and soil can
further be used to sequester some of the CO2 in the
atmosphere.
There
are several factors within the field of agriculture that contribute to the
large amount of CO2 emissions. The diversity of the sources ranges from the
production of farming tools to the transport of harvested produce.
Approximately 8% of the national carbon footprint is due to agricultural sources.
Of that, 75% is of the carbon emissions released from the production of crop
assisting chemicals. Factories producing
insecticides, herbicides, fungicides, and fertilizers are a major culprit of
the greenhouse gas. Productivity on the farm itself and the use of machinery is
another source of the carbon emission. Almost all the industrial machines used
in modern farming are powered by fossil fuels. These instruments are burning
fossil fuels from the beginning of the process to the end. Tractors are the
root of this source. The tractor is going to burn fuel and release CO2 just to
run. The amount of emissions from the machinery increase with the attachment of
different units and need for more power. During the soil preparation stage
tillers and plows will be used to disrupt the soil. During growth watering
pumps and sprayers are used to keep the crops hydrated. And when the crops are
ready for picking a forage or combine harvester is used. These types of
machinery all require additional energy which leads to increased carbon dioxide
emissions from the basic tractors. The final major
contribution to CO2 emissions in agriculture is in the final transport of
produce. Local farming suffered a decline over the past century due to large
amounts of farm subsidies. The majority of crops are shipped hundreds of miles
to various processing plants before ending up in the grocery store. These
shipments are made using fossil fuel burning modes of transportation.
Inevitably these transport adds to carbon dioxide emissions.
Sustainability
Some
major organisations are hailing farming within agroecosystems as the way forward
for mainstream agriculture. Current farming methods have resulted in
over-stretched water resources, high levels of erosion and reduced soil
fertility. According to a report ]there
is not enough water to continue farming using current practices; therefore how
critical water, land, and ecosystem resources are used
to boost crop yields must be reconsidered. The report suggested assigning value
to ecosystems, recognizing environmental and livelihood tradeoffs, and
balancing the rights of a variety of users and interests. Inequities that
result when such measures are adopted would need to be addressed, such as the
reallocation of water from poor to rich, the clearing of land to make way for
more productive farmland, or the preservation of a wetland system that limits
fishing rights.
Technological
advancements help provide farmers with tools and resources to make farming more
sustainable. New technologies
have given rise to innovations like conservation tillage, a farming process
which helps prevent land loss to erosion, water pollution and enhances carbon
sequestration.
Agricultural economics
Agricultural
economics refers to economics as it relates to the "production,
distribution and consumption of [agricultural] goods and services". Combining
agricultural production with general theories of marketing and business as a
discipline of study began in the late 1800s, and grew significantly through the
20th century. Although the study
of agricultural economics is relatively recent, major trends in agriculture
have significantly affected national and international economies throughout
history, ranging from tenant farmers and sharecropping in the post-American
Civil War
Southern
United States to the European feudal system of manorialism. In the United
States, and elsewhere, food costs attributed to food processing, distribution, and agricultural
marketing,
sometimes referred to as the value chain, have risen while the costs attributed
to farming have declined. This is related to the greater efficiency of farming,
combined with the increased level of value addition (e.g. more highly
processed products) provided by the supply chain. Market
concentration
has increased in the sector as well, and although the total effect of the
increased market concentration is likely increased efficiency, the changes
redistribute economic
surplus
from producers (farmers) and consumers, and may have negative implications for
rural communities.
National
government policies can significantly change the economic marketplace for
agricultural products, in the form of taxation, subsidies, tariffs and other measures. Since at least the
1960s, a combination of import/export restrictions, exchange
rate policies
and subsidies have affected farmers in both the developing and developed world.
In the 1980s, it was clear that non-subsidized farmers in developing countries
were experiencing adverse affects from national policies that created
artificially low global prices for farm products. Between the mid-1980s and the
early 2000s, several international agreements were put into place that limited
agricultural tariffs, subsidies and other trade restrictions.
However,
as of 2009, there was still a significant amount of policy-driven distortion in
global agricultural product prices. The three agricultural products with the
greatest amount of trade distortion were sugar, milk and rice, mainly due to
taxation. Among the oilseeds, sesame had the
greatest amount of taxation, but overall, feed grains and oilseeds had much
lower levels of taxation than livestock products. Since the 1980s,
policy-driven distortions have seen a greater decrease among livestock products
than crops during the worldwide reforms in agricultural policy. Despite this
progress, certain crops, such as cotton, still see subsidies in developed
countries artificially deflating global prices, causing hardship in developing
countries with non-subsidized farmers. Unprocessed
commodities (i.e. corn, soybeans, cows) are generally graded to indicate
quality. The quality affects the price the producer receives. Commodities are
generally reported by production quantities, such as volume, number or weight.
Energy and agriculture
Since
the 1940s, agricultural productivity has increased dramatically, due largely to
the increased use of energy-intensive mechanization, fertilizers and
pesticides. The vast majority of this energy input comes from fossil fuel sources.Between the 1960–65
measuring cycle and the cycle from 1986 to 1990, the Green Revolution transformed
agriculture around the globe, with world grain production increasing
significantly (between 70% and 390% for wheat and 60% to 150% for rice,
depending on geographic area) as world population doubled. Modern
agriculture's heavy reliance on petrochemicals and mechanization
has raised concerns that oil shortages could increase costs and reduce
agricultural output, causing food shortages.
Agriculture and food system share (%)
of total energy
consumption by three industrialized nations |
|||
Country
|
Year
|
Agriculture
(direct & indirect) |
Food
system |
United
Kingdom
|
2005
|
1.9
|
11
|
United
States
|
1996
|
2.1
|
10
|
United
States
|
2002
|
2.0
|
14
|
Sweden
|
2000
|
2.5
|
13
|
Modern
or industrialized agriculture is dependent on fossil fuels in two fundamental
ways: 1) direct consumption on the farm and 2) indirect consumption to
manufacture inputs used on the farm. Direct consumption includes the use of
lubricants and fuels to operate farm vehicles and machinery; and use of
gasoline, liquid propane, and electricity to
power dryers, pumps, lights, heaters, and coolers. American farms directly
consumed about 1.2 exajoules (1.1 quadrillion BTU) in 2002, or just over 1% of
the nation's total energy.
Indirect
consumption is mainly oil and natural gas used to manufacture
fertilizers and pesticides, which accounted for 0.6 exajoules (0.6 quadrillion
BTU) in 2002. The natural gas and
coal consumed by the production of nitrogen
fertilizer
can account for over half of the agricultural energy usage. China utilizes
mostly coal in the production of nitrogen fertilizer, while most of Europe uses
large amounts of natural gas and small amounts of coal. According to a 2010
report published by The Royal Society, agriculture is
increasingly dependent on the direct and indirect input of fossil fuels.
Overall, the fuels used in agriculture vary based on several factors, including
crop, production system and location.The energy used to
manufacture farm machinery is also a form of indirect agricultural energy
consumption. Together, direct and indirect consumption by US farms accounts for
about 2% of the nation's energy use. Direct and indirect energy consumption by
U.S. farms peaked in 1979, and has gradually declined over the past 30 years. Food systems encompass not just
agricultural production, but also off-farm processing, packaging, transporting,
marketing, consumption, and disposal of food and food-related items.
Agriculture accounts for less than one-fifth of food system energy use in the
US.
Mitigation of effects of petroleum
shortages
In
the event of a petroleum shortage (see peak oil for global
concerns), organic agriculture can be more attractive than conventional
practices that use petroleum-based pesticides, herbicides, or fertilizers. Some
studies using modern organic-farming methods have reported yields as high as
those available from conventional farming. In the aftermath of
the fall of the Soviet Union, with shortages of conventional
petroleum-based inputs, Cuba made use of mostly organic practices, including biopesticides, plant-based
pesticides and sustainable cropping practices, to feed its populace. However, organic
farming may be more labor-intensive and would
require a shift of the workforce from urban to rural areas.The reconditioning of
soil
to restore nutrients lost during the use of monoculture agriculture
techniques also takes time.
It
has been suggested that rural communities might obtain fuel from the biochar and synfuel process, which uses
agricultural waste to provide charcoal fertilizer, some fuel and
food, instead of the normal food vs fuel debate. As the
synfuel would be used on-site, the process would be more efficient and might
just provide enough fuel for a new organic-agriculture fusion.
It
has been suggested that some transgenic plants may some day be developed which would
allow for maintaining or increasing yields while requiring fewer
fossil-fuel-derived inputs than conventional crops. The possibility of
success of these programs is questioned by ecologists and economists concerned
with unsustainable GMO practices such as terminator seeds. While there has been
some research on sustainability using GMO crops, at least one prominent
multi-year attempt by Monsanto Company has been
unsuccessful, though during the same period traditional breeding techniques
yielded a more sustainable variety of the same crop.
Policy
Agricultural
policy
is the set of government decisions and actions relating to domestic agriculture
and imports of foreign agricultural products. Governments usually implement
agricultural policies with the goal of achieving a specific outcome in the
domestic agricultural product markets. Some overarching themes include risk
management and adjustment (including policies related to climate change, food safety and natural
disasters), economic
stability
(including policies related to taxes), natural resources and environmental sustainability (especially water policy), research and development, and market
access for domestic commodities (including relations with global organizations
and agreements with other countries). Agricultural policy
can also touch on food
quality,
ensuring that the food supply is of a consistent and known quality, food security, ensuring that the
food supply meets the population's needs, and conservation. Policy programs can
range from financial programs, such as subsidies, to encouraging producers to
enroll in voluntary quality assurance programs.
There
are many influences on the creation of agricultural policy, including
consumers, agribusiness, trade lobbies and other groups. Agribusiness interests hold a
large amount of influence over policy making, in the form of lobbying and campaign
contributions.
Political action groups, including those interested in environmental issues and
labor unions, also provide
influence, as do lobbying organizations representing individual agricultural
commodities. International effort
was made to defeat hunger and provides a forum for the negotiation of global agricultural
regulations and agreements. Dr. Samuel Jutzi, director of FAO's animal
production and health division, states that lobbying by large corporations has
stopped reforms that would improve human health and the environment. For
example, proposals in 2010 for a voluntary code of conduct for the livestock
industry that would have provided incentives for improving standards for
health, and environmental regulations, such as the number of animals an area of
land can support without long-term damage, were successfully defeated due to
large food company pressure.
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