What is the word agriculture mean

Agriculture encompasses crop and livestock production, aquaculture, fisheries and forestry for food and non-food products.^[1] Agriculture was the key development in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that enabled people to live in cities. While humans started gathering grains at least 105,000 years ago, nascent farmers only began planting them around 11,500 years ago. Sheep, goats, pigs and cattle were domesticated around 10,000 years ago. Plants were independently cultivated in at least 11 regions of the world. In the twentieth century, industrial agriculture based on large-scale monocultures came to dominate agricultural output.

Today, small farms produce about a third of the world’s food, but large farms are prevalent.^[2] The largest one percent of farms in the world are greater than 50 hectares and operate more than 70 percent of the world’s farmland.^[2] Nearly 40 percent of agricultural land is found on farms larger than 1,000 hectares.^[2] However, five of every six farms in the world consist of less than two hectares and take up only around 12 percent of all agricultural land.^[2]

The major agricultural products can be broadly grouped into foods, fibers, fuels, and raw materials (such as rubber). Food classes include cereals (grains), vegetables, fruits, cooking oils, meat, milk, eggs, and fungi. Global agricultural production amounts to approximately 11 billion tonnes of food,^[3] 32 million tonnes of natural fibres^[4] and 4 billion m³ of wood.^[5] However, around 14 percent of the world’s food is lost from production before reaching the retail level.^[6]

Modern agronomy, plant breeding, agrochemicals such as pesticides and fertilizers, and technological developments have sharply increased crop yields, but also contributed to ecological and environmental damage. Selective breeding and modern practices in animal husbandry have similarly increased the output of meat, but have raised concerns about animal welfare and environmental damage. Environmental issues include contributions to climate change, depletion of aquifers, deforestation, antibiotic resistance, and other agricultural pollution. Agriculture is both a cause of and sensitive to environmental degradation, such as biodiversity loss, desertification, soil degradation, and climate change, all of which can cause decreases in crop yield. Genetically modified organisms are widely used, although some countries ban them.

Etymology and scope

The word agriculture is a late Middle English adaptation of Latin agricultūra, from ager ‘field’ and cultūra ‘cultivation’ or ‘growing’.^[7] While agriculture usually refers to human activities, certain species of ant,^[8][9] termite and beetle have been cultivating crops for up to 60 million years.^[10] Agriculture is defined with varying scopes, in its broadest sense using natural resources to «produce commodities which maintain life, including food, fiber, forest products, horticultural crops, and their related services».^[11] Thus defined, it includes arable farming, horticulture, animal husbandry and forestry, but horticulture and forestry are in practice often excluded.^[11]
It may also be broadly decomposed into plant agriculture, which concerns the cultivation of useful plants,^[12] and animal agriculture, the production of agricultural animals.^[13]

History

Origins

The development of agriculture enabled the human population to grow many times larger than could be sustained by hunting and gathering.^[16] Agriculture began independently in different parts of the globe,^[17] and included a diverse range of taxa, in at least 11 separate centers of origin.^[14] Wild grains were collected and eaten from at least 105,000 years ago.^[18] In the Paleolithic Levant, 23,000 years ago, cereals cultivation of emmer, barley, and oats has been observed near the sea of Galilee.^[19][20] Rice was domesticated in China between 11,500 and 6,200 BC with the earliest known cultivation from 5,700 BC,^[21] followed by mung, soy and azuki beans. Sheep were domesticated in Mesopotamia between 13,000 and 11,000 years ago.^[22] Cattle were domesticated from the wild aurochs in the areas of modern Turkey and Pakistan some 10,500 years ago.^[23] Pig production emerged in Eurasia, including Europe, East Asia and Southwest Asia,^[24] where wild boar were first domesticated about 10,500 years ago.^[25] In the Andes of South America, the potato was domesticated between 10,000 and 7,000 years ago, along with beans, coca, llamas, alpacas, and guinea pigs. Sugarcane and some root vegetables were domesticated in New Guinea around 9,000 years ago. Sorghum was domesticated in the Sahel region of Africa by 7,000 years ago. Cotton was domesticated in Peru by 5,600 years ago,^[26] and was independently domesticated in Eurasia. In Mesoamerica, wild teosinte was bred into maize by 6,000 years ago.^[27] The horse was domesticated in the Eurasian Steppes around 3500 BC.^[28]
Scholars have offered multiple hypotheses to explain the historical origins of agriculture. Studies of the transition from hunter-gatherer to agricultural societies indicate an initial period of intensification and increasing sedentism; examples are the Natufian culture in the Levant, and the Early Chinese Neolithic in China. Then, wild stands that had previously been harvested started to be planted, and gradually came to be domesticated.^[29][30][31]

Civilizations

In Eurasia, the Sumerians started to live in villages from about 8,000 BC, relying on the Tigris and Euphrates rivers and a canal system for irrigation. Ploughs appear in pictographs around 3,000 BC; seed-ploughs around 2,300 BC. Farmers grew wheat, barley, vegetables such as lentils and onions, and fruits including dates, grapes, and figs.^[34] Ancient Egyptian agriculture relied on the Nile River and its seasonal flooding. Farming started in the predynastic period at the end of the Paleolithic, after 10,000 BC. Staple food crops were grains such as wheat and barley, alongside industrial crops such as flax and papyrus.^[35][36] In India, wheat, barley and jujube were domesticated by 9,000 BC, soon followed by sheep and goats.^[37] Cattle, sheep and goats were domesticated in Mehrgarh culture by 8,000–6,000 BC.^[38][39][40] Cotton was cultivated by the 5th–4th millennium BC.^[41] Archeological evidence indicates an animal-drawn plough from 2,500 BC in the Indus Valley civilisation.^[42]

In China, from the 5th century BC there was a nationwide granary system and widespread silk farming.^[43] Water-powered grain mills were in use by the 1st century BC,^[44] followed by irrigation.^[45] By the late 2nd century, heavy ploughs had been developed with iron ploughshares and mouldboards.^[46][47] These spread westwards across Eurasia.^[48] Asian rice was domesticated 8,200–13,500 years ago – depending on the molecular clock estimate that is used^[49]– on the Pearl River in southern China with a single genetic origin from the wild rice Oryza rufipogon.^[50] In Greece and Rome, the major cereals were wheat, emmer, and barley, alongside vegetables including peas, beans, and olives. Sheep and goats were kept mainly for dairy products.^[51][52]

In the Americas, crops domesticated in Mesoamerica (apart from teosinte) include squash, beans, and cacao.^[53] Cocoa was being domesticated by the Mayo Chinchipe of the upper Amazon around 3,000 BC.^[54]
The turkey was probably domesticated in Mexico or the American Southwest.^[55] The Aztecs developed irrigation systems, formed terraced hillsides, fertilized their soil, and developed chinampas or artificial islands. The Mayas used extensive canal and raised field systems to farm swampland from 400 BC.^{[56][57][58][59][60]} Coca was domesticated in the Andes, as were the peanut, tomato, tobacco, and pineapple.^[53] Cotton was domesticated in Peru by 3,600 BC.^[61] Animals including llamas, alpacas, and guinea pigs were domesticated there.^[62] In North America, the indigenous people of the East domesticated crops such as sunflower, tobacco,^[63] squash and Chenopodium.^[64][65] Wild foods including wild rice and maple sugar were harvested.^[66] The domesticated strawberry is a hybrid of a Chilean and a North American species, developed by breeding in Europe and North America.^[67] The indigenous people of the Southwest and the Pacific Northwest practiced forest gardening and fire-stick farming. The natives controlled fire on a regional scale to create a low-intensity fire ecology that sustained a low-density agriculture in loose rotation; a sort of «wild» permaculture.^{[68][69][70][71]} A system of companion planting called the Three Sisters was developed in North America. The three crops were winter squash, maize, and climbing beans.^[72][73]

Indigenous Australians, long supposed to have been nomadic hunter-gatherers, practised systematic burning, possibly to enhance natural productivity in fire-stick farming.^[74] Scholars have pointed out that hunter-gatherers need a productive environment to support gathering without cultivation. Because the forests of New Guinea have few food plants, early humans may have used «selective burning» to increase the productivity of the wild karuka fruit trees to support the hunter-gatherer way of life.^[75]

The Gunditjmara and other groups developed eel farming and fish trapping systems from some 5,000 years ago.^[76] There is evidence of ‘intensification’ across the whole continent over that period.^[77] In two regions of Australia, the central west coast and eastern central, early farmers cultivated yams, native millet, and bush onions, possibly in permanent settlements.^[31][78]

Revolution

In the Middle Ages, compared to the Roman period, agriculture in Western Europe became more focused on self-sufficiency. The agricultural population under feudalism was typically organized into manors consisting of several hundred or more acres of land presided over by a lord of the manor with a Roman Catholic church and priest.^[79]

Thanks to the exchange with the Al-Andalus where the Arab Agricultural Revolution was underway, European agriculture transformed, with improved techniques and the diffusion of crop plants, including the introduction of sugar, rice, cotton and fruit trees (such as the orange).^[80]

After 1492, the Columbian exchange brought New World crops such as maize, potatoes, tomatoes, sweet potatoes, and manioc to Europe, and Old World crops such as wheat, barley, rice, and turnips, and livestock (including horses, cattle, sheep and goats) to the Americas.^[81]

Irrigation, crop rotation, and fertilizers advanced from the 17th century with the British Agricultural Revolution, allowing global population to rise significantly. Since 1900, agriculture in developed nations, and to a lesser extent in the developing world, has seen large rises in productivity as mechanization replaces human labor, and assisted by synthetic fertilizers, pesticides, and selective breeding. The Haber-Bosch method allowed the synthesis of ammonium nitrate fertilizer on an industrial scale, greatly increasing crop yields and sustaining a further increase in global population.^[82][83]

Modern agriculture has raised or encountered ecological, political, and economic issues including water pollution, biofuels, genetically modified organisms, tariffs and farm subsidies, leading to alternative approaches such as the organic movement.^[84][85] Unsustainable farming practices in North America led to the Dust Bowl of the 1930s.^[86]

Types

Pastoralism involves managing domesticated animals. In nomadic pastoralism, herds of livestock are moved from place to place in search of pasture, fodder, and water. This type of farming is practised in arid and semi-arid regions of Sahara, Central Asia and some parts of India.^[87]

In shifting cultivation, a small area of forest is cleared by cutting and burning the trees. The cleared land is used for growing crops for a few years until the soil becomes too infertile, and the area is abandoned. Another patch of land is selected and the process is repeated. This type of farming is practiced mainly in areas with abundant rainfall where the forest regenerates quickly. This practice is used in Northeast India, Southeast Asia, and the Amazon Basin.^[88]

Subsistence farming is practiced to satisfy family or local needs alone, with little left over for transport elsewhere. It is intensively practiced in Monsoon Asia and South-East Asia.^[89] An estimated 2.5 billion subsistence farmers worked in 2018, cultivating about 60% of the earth’s arable land.^[90]

Intensive farming is cultivation to maximise productivity, with a low fallow ratio and a high use of inputs (water, fertilizer, pesticide and automation). It is practiced mainly in developed countries.^[91][92]

Contemporary agriculture

Status

From the twentieth century onwards, intensive agriculture increased crop productivity. It substituted synthetic fertilizers and pesticides for labour, but caused increased water pollution, and often involved farm subsidies. Soil degradation and diseases such as stem rust are major concerns globally;^[93] approximately 40% of the world’s agricultural land is seriously degraded.^[94][95] In recent years there has been a backlash against the environmental effects of conventional agriculture, resulting in the organic, regenerative, and sustainable agriculture movements.^[84][96] 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,^[97] also known as decoupling. The growth of organic farming has renewed research in alternative technologies such as integrated pest management, selective breeding,^[98] and controlled-environment agriculture.^[99][100] There are concerns about the lower yield associated with organic farming and its impact on global food security.^[101] Recent mainstream technological developments include genetically modified food.^[102]

By 2015, the agricultural output of China was the largest in the world, followed by the European Union, India and the United States.^[103] Economists measure the total factor productivity of agriculture, according to which agriculture in the United States is roughly 1.7 times more productive than it was in 1948.^[104]

Despite increases in agricultural production and productivity,^[105] between 702 and 828 million people were affected by hunger in 2021.^[106] Food insecurity and malnutrition can be the result of conflict, climate extremes and variability and economic swings.^[105] It can also be caused by a country’s structural characteristics such as income status and natural resource endowments as well as its political economy.^[105]

The International Fund for Agricultural Development posits that an increase in smallholder agriculture may be part of the solution to concerns about food prices and overall food security, given the favorable experience of Vietnam.^[107]

Workforce

Agriculture provides about one-quarter of all global employment, more than half in sub-Saharan Africa and almost 60 percent in low-income countries.^[108] As countries develop, other jobs have historically pulled workers away from agriculture, and labour-saving innovations increase agricultural productivity by reducing labour requirements per unit of output.^{[109][110][111]} Over time, a combination of labour supply and labour demand trends have driven down the share of population employed in agriculture.^[112][113]

During the 16th century in Europe, between 55 and 75% of the population was engaged in agriculture; by the 19th century, this had dropped to between 35 and 65%.^[114] In the same countries today, the figure is less than 10%.^[115]
At the start of the 21st century, some one billion people, or over 1/3 of the available work force, were employed in agriculture. This constitutes approximately 70% of the global employment of children, and in many countries constitutes the largest percentage of women of any industry.^[116] The service sector overtook the agricultural sector as the largest global employer in 2007.^[117]

In many developed countries, immigrants help fill labour shortages in high-value agriculture activities that are difficult to mechanize.^[118] Foreign farm workers from mostly Eastern Europe, North Africa and South Asia constituted around one-third of the salaried agricultural workforce in Spain, Italy, Greece and Portugal in 2013.^{[119][120][121][122]} In the United States of America, more than half of all hired farmworkers (roughly 450,000 workers) were immigrants in 2019, although the number of new immigrants arriving in the country to work in agriculture has fallen by 75 percent in recent years and rising wages indicate this has led to a major labor shortage on U.S. farms.^[123][124]

Around the world, women make up a large share of the population employed in agriculture.^[125] This share is growing in all developing regions except East and Southeast Asia where women already make up about 50 percent of the agricultural workforce.^[125] Women make up 47 percent of the agricultural workforce in sub-Saharan Africa, a rate that has not changed significantly in the past few decades.^[125] However, the Food and Agriculture Organization of the United Nations (FAO) posits that the roles and responsibilities of women in agriculture may be changing – for example, from subsistence farming to wage employment, and from contributing household members to primary producers in the context of male-out-migration.^[125]

Safety

Agriculture, specifically farming, 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.^[126] Pesticides and other chemicals used in farming can be hazardous to worker health, and workers exposed to pesticides may experience illness or have children with birth defects.^[127] 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.^[128] Ages 0–6 May be an especially vulnerable population in agriculture;^[129] common causes of fatal injuries among young farm workers include drowning, machinery and motor accidents, including with all-terrain vehicles.^{[128][129][130]}

The International Labour Organization considers agriculture «one of the most hazardous of all economic sectors».^[116] 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.^[131] 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.^[116]

In the United States, agriculture has been identified by the National Institute for Occupational Safety and Health as a priority industry sector in the National Occupational Research Agenda to identify and provide intervention strategies for occupational health and safety issues.^[132][133]
In the European Union, the European Agency for Safety and Health at Work has issued guidelines on implementing health and safety directives in agriculture, livestock farming, horticulture, and forestry.^[134] The Agricultural Safety and Health Council of America (ASHCA) also holds a yearly summit to discuss safety.^[135]

Production

Overall production varies by country as listed.

Largest countries by agricultural output (in nominal terms) according to IMF and CIA World Factbook, at peak level as of 2018

Economy Countries by agricultural output (in nominal terms) at peak level as of 2018 (billions in USD) (01)  China 1,117 (02)  India 414 (—)  European Union 308 (03)  United States 185 (04)  Brazil 162 (05)  Indonesia 141 (06)  Nigeria 123 (07)  Russia 108 (08)  Pakistan 76 (09)  Argentina 70 (10)  Turkey 64 (11)  Japan 62 (12)  France 59 (13)  Iran 57 (14)  Australia 56 (15)  Mexico 51 (16)  Italy 50 (17)  Spain 43 (18)  Bangladesh 41 (19)  Thailand 40 (20)  Egypt 40 The twenty largest countries by agricultural output (in nominal terms) at peak level as of 2018, according to the IMF and CIA World Factbook.

Largest countries by agricultural output according to UNCTAD at 2005 constant prices and exchange rates, 2015[103]
Economy Countries by agricultural output in 2015 (millions in 2005 constant USD and exchange rates) (01)  China 418,455 (02)  India 196,592 (03)  United States 149,023 (04)  Nigeria 77,113 (05)  Brazil 59,977

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.^[137][138]

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.^[139] 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.^[139]

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.^[138] 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.^[139]

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 farming is the dominant agricultural system.^[139]

Important categories of food crops include cereals, legumes, forage, fruits and vegetables.^[140] Natural fibers include cotton, wool, hemp, silk and flax.^[141] Specific crops are cultivated in distinct growing regions throughout the world. Production is listed in millions of metric tons, based on FAO estimates.^[140]

Top agricultural products, by crop types (million tonnes) 2004 data
Cereals	2,263
Vegetables and melons	866
Roots and tubers	715
Milk	619
Fruit	503
Meat	259
Oilcrops	133
Fish (2001 estimate)	130
Eggs	63
Pulses	60
Vegetable fiber	30
Source: Food and Agriculture Organization[140]

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
Source: Food and Agriculture Organization[140]

Livestock production systems

Animal husbandry is the breeding and raising of animals for meat, milk, eggs, or wool, and for work and transport.^[142] Working animals, including horses, mules, oxen, water buffalo, camels, llamas, alpacas, donkeys, and dogs, have for centuries been used to help cultivate fields, harvest crops, wrangle other animals, and transport farm products to buyers.^[143]

Livestock production systems can be defined based on feed source, as grassland-based, mixed, and landless.^[144] 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.^[145] 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.^[146]

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.^[147]

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.^[139] 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.^[144]

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 member countries. Synthetic fertilizers are more heavily relied upon for crop production and manure use becomes a challenge as well as a source for pollution.^[144] 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.^[145] Some of the practices used in commercial livestock production, including the usage of growth hormones, are controversial.^[148]

Production practices

Tillage is the practice of breaking up the soil with tools such as the plow or harrow to prepare for planting, for nutrient incorporation, or for pest control. Tillage varies in intensity from conventional to no-till. It can 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.^[149][150]

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.^[151]

Nutrient management includes both the source of nutrient inputs for crop and livestock production, and the method of use of manure produced by livestock. Nutrient inputs can be chemical inorganic fertilizers, manure, green manure, compost and minerals.^[152] 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.^[149][153]

Water management is needed where rainfall is insufficient or variable, which occurs to some degree in most regions of the world.^[139] 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 for the following year.^[154] Recent technological innovations in precision agriculture allow for water status monitoring and automate water usage, leading to more efficient management.^[155] Agriculture represents 70% of freshwater use worldwide.^[156] However, water withdrawal ratios for agriculture vary significantly by income level. In least developed countries and landlocked developing countries, water withdrawal ratios for agriculture are as high as 90 percent of total water withdrawals and about 60 percent in Small Island Developing States.^[157]

According to 2014 report by the International Food Policy Research Institute, agricultural technologies will have the greatest impact on food production if adopted in combination with each other. Using a model that assessed how eleven technologies could impact agricultural productivity, food security and trade by 2050, the International Food Policy Research Institute found that the number of people at risk from hunger could be reduced by as much as 40% and food prices could be reduced by almost half.^[158]

Payment for ecosystem services is a method of providing additional incentives to encourage farmers to conserve some aspects of the environment. Measures might include paying for reforestation upstream of a city, to improve the supply of fresh water.^[159]

Agricultural automation

Different definitions exist for agricultural automation and for the variety of tools and technologies that are used to automate production. One view is that agricultural automation refers to autonomous navigation by robots without human intervention.^[160] Alternatively it is defined as the accomplishment of production tasks through mobile, autonomous, decision-making, mechatronic devices.^[161] However, FAO finds that these definitions do not capture all the aspects and forms of automation, such as robotic milking machines that are static, most motorized machinery that automates the performing of agricultural operations, and digital tools (e.g. sensors) that automate only diagnosis.^[155] FAO defines agricultural automation as the use of machinery and equipment in agricultural operations to improve their diagnosis, decision-making or performing, reducing the drudgery of agricultural work and/or improving the timeliness, and potentially the precision, of agricultural operations.^[162]

The technological evolution in agriculture has involved a progressive move from manual tools to animal traction, to motorized mechanization, to digital equipment and finally, to robotics with artificial intelligence (AI).^[162] Motorized mechanization using engine power automates the performance of agricultural operations such as ploughing and milking.^[163] With digital automation technologies, it also becomes possible to automate diagnosis and decision-making of agricultural operations.^[162] For example, autonomous crop robots can harvest and seed crops, while drones can gather information to help automate input application.^[155] Precision agriculture often employs such automation technologies.^[155] Motorized machines are increasingly complemented, or even superseded, by new digital equipment that automates diagnosis and decision-making.^[163] A conventional tractor, for example, can be converted into an automated vehicle allowing it to sow a field autonomously.^[163]

Motorized mechanization has increased significantly across the world in recent years, although reliable global data with broad country coverage exist only for tractors and only up to 2009.^[164] Sub-Saharan Africa is the only region where the adoption of motorized mechanization has stalled over the past decades.^[155][165]

Automation technologies are increasingly used for managing livestock, though evidence on adoption is lacking. Global automatic milking system sales have increased over recent years,^[166] but adoption is likely mostly in Northern Europe,^[167] and likely almost absent in low- and middle-income countries. Automated feeding machines for both cows and poultry also exist, but data and evidence regarding their adoption trends and drivers is likewise scarce.^[168][155]

Measuring the overall employment impacts of agricultural automation is difficult because it requires large amounts of data tracking all the transformations and the associated reallocation of workers both upstream and downstream.^[162] While automation technologies reduce labour needs for the newly automated tasks, they also generate new labour demand for other tasks, such as equipment maintenance and operation.^[155] Agricultural automation can also stimulate employment by allowing producers to expand production and by creating other agrifood systems jobs.^[169] This is especially true when it happens in context of rising scarcity of rural labour, as is the case in high-income countries and many middle-income countries.^[169] On the other hand, if forcedly promoted, for example through government subsidies in contexts of abundant rural labour, it can lead to labour displacement and falling or stagnant wages, particularly affecting poor and low-skilled workers.^[169]

Effects of climate change on yields

Climate change and agriculture are interrelated on a global scale. Climate change affects agriculture through changes in average temperatures, rainfall, and weather extremes (like storms and heat waves); changes in pests and diseases; changes in atmospheric carbon dioxide and ground-level ozone concentrations; changes in the nutritional quality of some foods;^[170] and changes in sea level.^[171] Global warming is already affecting agriculture, with effects unevenly distributed across the world.^[172]

In a 2022 report, the Intergovernmental Panel on Climate Change describes how human-induced warming has slowed growth of agricultural productivity over the past 50 years in mid and low latitudes.^[173] Methane emissions have negatively impacted crop yields by increasing temperatures and surface ozone concentrations.^[173] Warming is also negatively affecting crop and grassland quality and harvest stability.^[173] Ocean warming has decreased sustainable yields of some wild fish populations while ocean acidification and warming have already affected farmed aquatic species.^[173] Climate change will probably increase the risk of food insecurity for some vulnerable groups, such as the poor.^[174]

Crop alteration and biotechnology

Plant breeding

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.^[175]

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.^[176][177]

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 US 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, and growth control to avoid lodging).^{[178][179][180]}

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 use 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.^[181] For some, GMO crops cause food safety and food labeling concerns. Numerous countries have placed restrictions on the production, import or use of GMO foods and crops.^[182] The Biosafety Protocol, an international treaty, 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.^[183]

Herbicide-resistant seeds have a gene implanted into their genome that allows the plants to tolerate exposure to herbicides, including glyphosate. 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.^[184] 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.^[185][186] 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.^[187]

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 resist damage by insects.^[188] 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.^[189]

Environmental impact

Effects and costs

Agriculture is both a cause of and sensitive to environmental degradation, such as biodiversity loss, desertification, soil degradation and climate change, which cause decreases in crop yield.^[190] Agriculture is one of the most important drivers of environmental pressures, particularly habitat change, climate change, water use and toxic emissions. Agriculture is the main source of toxins released into the environment, including insecticides, especially those used on cotton.^{[191][192][page needed]} The 2011 UNEP Green Economy report stated that agricultural operations produced some 13 per cent of anthropogenic global greenhouse gas emissions. This includes gases from the use of inorganic fertilizers, agro-chemical pesticides, and herbicides, as well as fossil fuel-energy inputs.^[193]

Agriculture imposes multiple external costs upon society through effects such as pesticide damage to nature (especially herbicides and insecticides), nutrient runoff, excessive water usage, and loss of natural environment. A 2000 assessment of agriculture in the UK determined total external costs for 1996 of £2,343 million, or £208 per hectare.^[194] A 2005 analysis of these costs in the US concluded that cropland imposes approximately $5 to $16 billion ($30 to $96 per hectare), while livestock production imposes $714 million.^[195] 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.^[194][195]

Agriculture seeks to increase yield and to reduce costs, often employing measures that cut biodiversity to very low levels. Yield increases with inputs such as fertilisers and removal of pathogens, predators, and competitors (such as weeds). Costs decrease with increasing scale of farm units, such as making fields larger; this means removing hedges, ditches and other areas of habitat. Pesticides kill insects, plants and fungi. Effective yields fall with on-farm losses, which may be caused by poor production practices during harvesting, handling, and storage.^[196]

The environmental effects of climate change show that research on pests and diseases that do not generally afflict areas is essential. In 2021, farmers discovered stem rust on wheat in the Champagne area of France, a disease that had previously only occurred in Morocco for 20 to 30 years. Because of climate change, insects that used to die off over the winter are now alive and multiplying.^[197][198]

Livestock issues

A senior UN official, Henning Steinfeld, said that «Livestock are one of the most significant contributors to today’s most serious environmental problems».^[199] 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 feed crops.^[200] Through deforestation and land degradation, livestock is also driving reductions in biodiversity. Furthermore, the United Nations Environment Programme (UNEP) states that «methane emissions from global livestock are projected to increase by 60 per cent by 2030 under current practices and consumption patterns.»^[193]

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 the driving force causing biodiversity loss. Estimates of the amount of land transformed by humans vary from 39 to 50%.^[201] Land degradation, the long-term decline in ecosystem function and productivity, is estimated to be occurring on 24% of land worldwide, with cropland overrepresented.^[202] Land management is the driving factor behind degradation; 1.5 billion people rely upon the degrading land. Degradation can be through deforestation, desertification, soil erosion, mineral depletion, acidification, or salinization.^[139]

Eutrophication, excessive nutrient enrichment 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 and pollution of groundwater, with harmful effects on human populations.^[203] Fertilisers also reduce terrestrial biodiversity by increasing competition for light, favouring those species that are able to benefit from the added nutrients.^[204]

Agriculture simultaneously is facing growing freshwater demand and precipitation anomalies (droughts, floods, and extreme rainfall and weather events) on rainfed areasfields and grazing lands.^[157] Agriculture accounts for 70 percent of withdrawals of freshwater resources,^[205][206] and an estimated 41 percent of current global irrigation water use occurs at the expense of environmental flow requirements.^[157] 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.^[207] 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.^[208] While industrial withdrawals have declined in the past few decades and municipal withdrawals have increased only marginally since 2010, agricultural withdrawals have continued to grow at an ever faster pace.^[157] 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.^[209]

Pesticides

Pesticide use has increased since 1950 to 2.5 million short tons annually worldwide, yet crop loss from pests has remained relatively constant.^[210] The World Health Organization estimated in 1992 that three million pesticide poisonings occur annually, causing 220,000 deaths.^[211] 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.^[212]

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’.^[213][214] However, critics argue that a trade-off between the environment and a need for food is not inevitable,^[215] and that pesticides can replace good agronomic practices such as crop rotation.^[212] The Push–pull agricultural pest management technique involves intercropping, using plant aromas to repel pests from crops (push) and to lure them to a place from which they can then be removed (pull).^[216]

Contribution to climate change

Agriculture contributes towards climate change through greenhouse gas emissions and by the conversion of non-agricultural land such as forests into agricultural land.^[217] The agriculture, forestry and land use sector contribute between 13% and 21% of global greenhouse gas emissions.^[218] Emissions of nitrous oxide, methane make up over half of total greenhouse gas emission from agriculture.^[219] Animal husbandry is a major source of greenhouse gas emissions.^[220]

Approximately 57% of global GHG emissions from the production of food are from the production of animal-based food while plant-based foods contribute 29% and the remaining 14% is for other utilizations.^[221] Farmland management and land-use change represented major shares of total emissions (38% and 29%, respectively), whereas rice and beef were the largest contributing plant- and animal-based commodities (12% and 25%, respectively).^[221] South and Southeast Asia and South America were the largest emitters of production-based GHGs.^[221]

Sustainability

Current farming methods have resulted in over-stretched water resources, high levels of erosion and reduced soil fertility. There is not enough water to continue farming using current practices; therefore how water, land, and ecosystem resources are used to boost crop yields must be reconsidered. A solution would be to give value to ecosystems, recognizing environmental and livelihood tradeoffs, and balancing the rights of a variety of users and interests.^[222] 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.^[223]

Technological advancements help provide farmers with tools and resources to make farming more sustainable.^[224] Technology permits innovations like conservation tillage, a farming process which helps prevent land loss to erosion, reduces water pollution, and enhances carbon sequestration.^[225]

Agricultural automation can help address some of the challenges associated with climate change and thus facilitate adaptation efforts.^[155] For example, the application of digital automation technologies (e.g. in precision agriculture) can improve resource-use efficiency in conditions which are increasingly constrained for agricultural producers.^[155] Moreover, when applied to sensing and early warning, they can help address the uncertainty and unpredictability of weather conditions associated with accelerating climate change.^[155]

Other potential sustainable practices include conservation agriculture, agroforestry, improved grazing, avoided grassland conversion, and biochar.^[226][227] Current mono-crop farming practices in the United States preclude widespread adoption of sustainable practices, such as 2-3 crop rotations that incorporate grass or hay with annual crops, unless negative emission goals such as soil carbon sequestration become policy.^[228]

The food demand of Earth’s projected population, with current climate change predictions, could be satisfied by improvement of agricultural methods, expansion of agricultural areas, and a sustainability-oriented consumer mindset.^[229]

Energy dependence

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.^[230] Between the 1960s and the 1980s, 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)^[231] as world population doubled. Heavy reliance on petrochemicals has raised concerns that oil shortages could increase costs and reduce agricultural output.^[232]

Industrialized agriculture depends on fossil fuels in two fundamental ways: direct consumption on the farm and manufacture of inputs used on the farm. Direct consumption includes the use of lubricants and fuels to operate farm vehicles and machinery.^[232]

Indirect consumption includes the manufacture of fertilizers, pesticides, and farm machinery.^[232] In particular, the production of nitrogen fertilizer can account for over half of agricultural energy usage.^[233] 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 since gradually declined.^[232] Food systems encompass not just agriculture but 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.^[234][235]

Plastic pollution

Plastic products are used extensively in agriculture, including to increase crop yields and improve the efficiency of water and agrichemical use. «Agriplastic» products include films to cover greenhouses and tunnels, mulch to cover soil (e.g. to suppress weeds, conserve water, increase soil temperature and aid fertilizer application), shade cloth, pesticide containers, seedling trays, protective mesh and irrigation tubing. The polymers most commonly used in these products are low- density polyethylene (LPDE), linear low-density polyethylene (LLDPE), polypropylene (PP) and polyvinyl chloride (PVC).^[236]

The total amount of plastics used in agriculture is difficult to quantify. A 2012 study reported that almost 6.5 million tonnes per year were consumed globally while a later study estimated that global demand in 2015 was between 7.3 million and 9 million tonnes. Widespread use of plastic mulch and lack of systematic collection and management have led to the generation of large amounts of mulch residue. Weathering and degradation eventually cause the mulch to fragment. These fragments and larger pieces of plastic accumulate in soil. Mulch residue has been measured at levels of 50 to 260 kg per hectare in topsoil in areas where mulch use dates back more than 10 years, which confirms that mulching is a major source of both microplastic and macroplastic soil contamination.^[236]

Agricultural plastics, especially plastic films, are not easy to recycle because of high contamination levels (up to 40- 50% by weight contamination by pesticides, fertilizers, soil and debris, moist vegetation, silage juice water, and UV stabilizers) and collection difficulties . Therefore, they are often buried or abandoned in fields and watercourses or burned. These disposal practices lead to soil degradation and can result in contamination of soils and leakage of microplastics into the marine environment as a result of precipitation run-off and tidal washing. In addition, additives in residual plastic film (such as UV and thermal stabilizers) may have deleterious effects on crop growth, soil structure, nutrient transport and salt levels. There is a risk that plastic mulch will deteriorate soil quality, deplete soil organic matter stocks, increase soil water repellence and emit greenhouse gases. Microplastics released through fragmentation of agricultural plastics can absorb and concentrate contaminants capable of being passed up the trophic chain.^[236]

Disciplines

Agricultural economics

Agricultural economics is economics as it relates to the «production, distribution and consumption of [agricultural] goods and services».^[238] 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.^[239] 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^[240] to the European feudal system of manorialism.^[241] 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.^[242]

National government policies, such as taxation, subsidies, tariffs and others, can significantly change the economic marketplace for agricultural products.^[243] Since at least the 1960s, a combination of trade restrictions, exchange rate policies and subsidies have affected farmers in both the developing and the developed world. In the 1980s, non-subsidized farmers in developing countries experienced adverse effects from national policies that created artificially low global prices for farm products. Between the mid-1980s and the early 2000s, several international agreements limited agricultural tariffs, subsidies and other trade restrictions.^[244]

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 most trade distortion were sugar, milk and rice, mainly due to taxation. Among the oilseeds, sesame had the most taxation, but overall, feed grains and oilseeds had much lower levels of taxation than livestock products. Since the 1980s, policy-driven distortions have decreases more among livestock products than crops during the worldwide reforms in agricultural policy.^[243] 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.^[245] Unprocessed commodities such as corn, soybeans, and cattle are generally graded to indicate quality, affecting the price the producer receives. Commodities are generally reported by production quantities, such as volume, number or weight.^[246]

Agricultural science

Agricultural science is a broad multidisciplinary field of biology that encompasses the parts of exact, natural, economic and social sciences used in the practice and understanding of agriculture. It covers topics such as agronomy, plant breeding and genetics, plant pathology, crop modelling, soil science, entomology, production techniques and improvement, study of pests and their management, and study of adverse environmental effects such as soil degradation, waste management, and bioremediation.^[247][248]

The scientific study of agriculture began in the 18th century, when Johann Friedrich Mayer conducted experiments on the use of gypsum (hydrated calcium sulphate) as a fertilizer.^[249] Research became more systematic when in 1843, John Lawes and Henry Gilbert began a set of long-term agronomy field experiments at Rothamsted Research Station in England; some of them, such as the Park Grass Experiment, are still running.^[250][251] In America, the Hatch Act of 1887 provided funding for what it was the first to call «agricultural science», driven by farmers’ interest in fertilizers.^[252] In agricultural entomology, the USDA began to research biological control in 1881; it instituted its first large program in 1905, searching Europe and Japan for natural enemies of the gypsy moth and brown-tail moth, establishing parasitoids (such as solitary wasps) and predators of both pests in the US.^{[253][254][255]}

Policy

Direct subsidies for animal products and feed by OECD countries in 2012, in billions of US dollars^[256]

Product	Subsidy
Beef and veal	18.0
Milk	15.3
Pigs	7.3
Poultry	6.5
Soybeans	2.3
Eggs	1.5
Sheep	1.1

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).^[257] 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.^[258]

A 2021 report finds that globally, support to agricultural producers accounts for almost US$540 billion a year.^[259] This amounts to 15 percent of total agricultural production value, and is heavily biased towards measures that are leading to inefficiency, as well as are unequally distributed and harmful for the environment and human health.^[259]  

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.^[260] The Food and Agriculture Organization of the United Nations (FAO) leads international efforts to defeat hunger and provides a forum for the negotiation of global agricultural regulations and agreements. 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.^[261]

See also

References

Cited sources

• Acquaah, George (2002). Principles of Crop Production: Theory, Techniques, and Technology. Prentice Hall. ISBN 978-0-13-022133-9.
• Chrispeels, Maarten J.; Sadava, David E. (1994). Plants, Genes, and Agriculture. Boston, Massachusetts: Jones and Bartlett. ISBN 978-0-86720-871-9.
• Needham, Joseph (1986). Science and Civilization in China. Taipei: Caves Books.

 This article incorporates text from a free content work. Licensed under CC BY-SA 3.0 IGO (license statement/permission). Text taken from Drowning in Plastics – Marine Litter and Plastic Waste Vital Graphics​, United Nations Environment Programme. To learn how to add open license text to Wikipedia articles, please see this how-to page. For information on reusing text from Wikipedia, please see the terms of use.

 This article incorporates text from a free content work. (license statement/permission). Text taken from In Brief: The State of Food and Agriculture 2019. Moving forward on food loss and waste reduction​, FAO, FAO. To learn how to add open license text to Wikipedia articles, please see this how-to page. For information on reusing text from Wikipedia, please see the terms of use.

 This article incorporates text from a free content work. (license statement/permission). Text taken from In Brief to The State of Food Security and Nutrition in the World 2022. Repurposing food and agricultural policies to make healthy diets more affordable​, FAO. To learn how to add open license text to Wikipedia articles, please see this how-to page. For information on reusing text from Wikipedia, please see the terms of use.

 This article incorporates text from a free content work. (license statement/permission). Text taken from In Brief: The State of Food and Agriculture 2018. Migration, agriculture and rural development​, FAO, FAO. To learn how to add open license text to Wikipedia articles, please see this how-to page. For information on reusing text from Wikipedia, please see the terms of use.

 This article incorporates text from a free content work. (license statement/permission). Text taken from In Brief to The State of Food and Agriculture 2022. Leveraging automation in agriculture for transforming agrifood systems​, FAO, FAO. To learn how to add open license text to Wikipedia articles, please see this how-to page. For information on reusing text from Wikipedia, please see the terms of use.

 This article incorporates text from a free content work. (license statement/permission). Text taken from Enabling inclusive agricultural automation​, FAO, FAO. To learn how to add open license text to Wikipedia articles, please see this how-to page. For information on reusing text from Wikipedia, please see the terms of use.

External links

• Food and Agriculture Organization
• United States Department of Agriculture
• Agriculture material from the World Bank Group
• Agriculture collected news and commentary at The New York Times
• Agriculture collected news and commentary at The Guardian

Agriculture or farming is the practice of cultivating plants and livestock. Agriculture was the key development in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that enabled people to live in cities.

Full
Answer

Why is agriculture important and its role in everyday life?

Definition of agriculture : the science, art, or practice of cultivating the soil, producing crops, and raising livestock and in varying degrees the preparation and marketing of the resulting products cleared the land to use it for agriculture

Agriculture definition, the science, art, or occupation concerned with cultivating land, raising crops, and feeding, breeding, and raising livestock; farming. See more.

What does the word agriculture mean?

Agriculture describes the practice of growing crops or raising animals. Someone who works as a farmer is in the agriculture industry. The Latin root of agriculture is agri, or “field,” plus cultura, …

What do you mean by agriculture ‘?

Agriculture is the art and science of cultivating the soil, growing crops and raising livestock. It includes the preparation of plant and animal products for people to use and their distribution to markets. Agriculture provides most of the world’s food and fabrics.

What does the term agriculture mean quizlet?

Agriculture. Definition: The deliberate effort to modify a portion of Earth’s surface through the cultivation of crops and the raising of livestock for sustenance or economic gain.

What is agriculture and where did it begin?

Agricultural communities developed approximately 10,000 years ago when humans began to domesticate plants and animals. By establishing domesticity, families and larger groups were able to build communities and transition from a nomadic hunter-gatherer lifestyle dependent on foraging and hunting for survival.

When and where did agriculture start quizlet?

Farming yielded a bigger and more reliable food source. It started in the fertile crescent around 10,000 BCE and grew hugely after 8,000 BCE.

What are FFA colors?

National blue and corn gold are adopted as official FFA colors.

What is no tillage AP Human Geography?

No tillage. Definition: A farming practice that leaves all of the soil undisturbed and the entire residue of the previous years left untouched on the fields. Example: No tillage farming is natural composte. Overfishing.

What is extensive farming AP Human Geography?

4:147:44Intensive & Extensive Agricultural Practices [AP Human Geography …YouTubeStart of suggested clipEnd of suggested clipExamples of extensive. Agriculture could be shifting cultivation no matter herding or ranching justMoreExamples of extensive. Agriculture could be shifting cultivation no matter herding or ranching just to name a few shifting cultivation is often located in more tropical.

Where does grain come from?

Grain is the harvested seed of grasses such as wheat, oats, rice, sorghum, millet, rye, and barley. Grain is the harvested seed of grasses such as wheat, oats, rice, and corn. Other important grains include sorghum, millet, rye, and barley.

What is the science of agriculture?

the science, art, or occupation concerned with cultivating land, raising crops, and feeding, breeding, and raising livestock; farming. the production of crops, livestock, or poultry. agronomy.

How did agriculture help the population?

Agriculture supported larger populations and gave them more goods to fight over.

Is English agriculture clean?

English Agriculture has a thorough and cleanly aspect which I have rarely observed elsewhere.

What is the origin of agriculture?

The word agriculture is a late Middle English adaptation of Latin agricultūra, from ager, “field”, and cultūra, ” cultivation ” or “growing”. While agriculture usually refers to human activities, certain species of ant, termite and beetle have been cultivating crops for up to 60 million years.

Why is agriculture important?

Agriculture is both a cause of and sensitive to environmental degradation, such as biodiversity loss, desertification, soil degradation and global warming, all of which can cause decreases in crop yield. Genetically modified organisms are widely used, although some are banned in certain countries.

How does livestock affect the environment?

A senior UN official, Henning Steinfeld, said that “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 CO 2 equivalents. By comparison, all transportation emits 13.5% of the CO 2. It produces 65% of human-related nitrous oxide (which has 296 times the global warming potential of CO 2) and 37% of all human-induced methane (which is 23 times as warming as CO 2 .) 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. Furthermore, the UNEP states that ” methane emissions from global livestock are projected to increase by 60 per cent by 2030 under current practices and consumption patterns.”

What is the basis of pastoral agriculture for several Arctic and Subarctic peoples?

Reindeer herds form the basis of pastoral agriculture for several Arctic and Subarctic peoples.

How does agriculture increase yield?

Agriculture seeks to increase yield and to reduce costs. Yield increases with inputs such as fertilisers and removal of pathogens , predators, and competitors (such as weeds). Costs decrease with increasing scale of farm units, such as making fields larger; this means removing hedges, ditches and other areas of habitat.

What was the Arab agricultural revolution?

The Arab Agricultural Revolution, starting in Al-Andalus (Islamic Spain), transformed agriculture with improved techniques and the diffusion of crop plants.

How many people were employed in agriculture in the 21st century?

At the start of the 21st century, some one billion people, or over 1/3 of the available work force, were employed in agriculture. It constitutes approximately 70% of the global employment of children, and in many countries employs the largest percentage of women of any industry.

What is agriculture in agriculture?

Cultivating a piece of land, or planting and growing food plants on it, is largely what agriculture means. Raising animals for meat or milk also falls under the category of agriculture. If we didn’t have agriculture, we’d all be running around the woods, picking berries and trying to shoot things.

What is the root of agriculture?

agriculture. Agriculture describes the practice of growing crops or raising animals. Someone who works as a farmer is in the agriculture industry. The Latin root of agriculture is agri, or “field,” plus cultura, “cultivation.”.

What is the cultivation of trees?

the cultivation of tree for the production of timber. dairy farming, dairying. the business of a dairy. gardening, horticulture. the cultivation of plants. aquiculture, hydroponics, tank farming. a technique of growing plants (without soil) in water containing dissolved nutrients. mixed farming.

What is mixed farming?

mixed farming. growing crops and feed and livestock all on the same farm. planting. putting seeds or young plants in the ground to grow. ranching. farming for the raising of livestock (particularly cattle) strip cropping. cultivation of crops in strips following the contours of the land to minimize erosion.

What is the term for growing vegetables for the market?

growing vegetables for the market. drip culture . a hydroponic method of growing plants by allowing nutrient solutions to drip slowly onto an inert medium in which the plants are growing. insemination. the act of sowing (of seeds in the ground or, figuratively, of germs in the body or ideas in the mind, etc.)

What is the definition of roundup?

the cultivation of flowering plants. roundup. the activity of gathering livestock together so that they can be counted or branded or sold. type of: cultivation. (agriculture) production of food by preparing the land to grow crops (especially on a large scale) noun.

What is the science of agriculture?

Agriculture is the art and science of cultivating the soil, growing crops and raising livestock. It includes the preparation of plant and animal products for people to use and their distribution to markets. Agriculture provides most of the world’s food and fabrics. Cotton, wool, and leather are all agricultural products.

Where did agriculture originate?

The earliest civilizations based on intensive agriculture arose near the Tigris and Euphrates Rivers in Mesopotamia (now Iraq and Iran) and along the Nile River in Egypt. Improved Technology. For thousands of years, agricultural development was very slow. One of the earliest agricultural tools was fire.

What is the science of growing plants in nutrient solutions?

Agriculture includes such forms of cultivation as hydroponics and aquaculture. Both involve farming in water. Hydroponics is the science of growing plants in nutrient solutions. Just one acre of nutrient solution can yield more than 50 times the amount of lettuce grown on the same amount of soil.

What did the Islamic Golden Age do to agriculture?

This system preserved nutrients in the soil, increasing crop production. The leaders of the Islamic Golden Age (which reached its height around 1000) in North Africa and the Middle East made agriculture into a science. Islamic Golden Age farmers learned crop rotation.

How big was the average farm in 2007?

The size of an average farm in the United States in 2007 was 449 acres, or about the size of 449 football fields. agriculture. Noun. the art and science of cultivating land for growing crops (farming) or raising livestock (ranching). aquaculture.

How did agriculture help people?

Agriculture enabled people to produce surplus food. They could use this extra food when crops failed or trade it for other goods. Food surpluses allowed people to work at other tasks unrelated to farming. Agriculture kept formerly nomadic people near their fields and led to the development of permanent villages.

What countries used old agriculture?

Farmers in Asia, Australia, Africa, and South America continued to use old ways of agriculture. Agricultural Science. In the early 1900s, an average farmer in the U.S. produced enough food to feed a family of five. Many of today’s farmers can feed that family and a hundred other people.

What is agriculture?

1. Agriculture is an enterprise or business, activity, or practice. It is synonymous with farming.

What is agriculture in biology?

2. Agriculture is the growth of both plants and animals for human needs (Abellanosa, A.L. and H.M. Pava. 1987. Introduction to Crop Science. Central Mindanao University, Musuan, Bukidnon: Publications Office. p. 238).

What is agricultural enterprise?

Agriculture, Agricultural Enterprise or Agricultural Activity means the cultivation of the soil, planting of crops, growing of fruit trees, including the harvesting of such farm products, and other farm activities and practices performed by a farmer in conjunction with such farming operations done by persons whether natural or juridical. (Sec. 3b, Chapter I, Comprehensive Agrarian Reform Law of 1988 (R.A. No. 6657 as amended by R. A. 7881), Philippines. Retrieved September 2, 2010, from http://www.chanrobles.com/legal4agrarianlaw.htm.

What is the purpose of the plant?

It has two main divisions: plant or crop production and animal or livestock production; and its ultimate purpose is for food production, other human needs such as clothing, medicines, tools, artistic display, dwelling, and feed for animals, or for economic gain or profit.

What is the science and practice of producing plants, other crops, and animals for food, other human needs, or economic

Agriculture is the science and practice of producing plants, other crops, and animals for food, other human needs, or economic gain.

What is agriculture especially convenient?

Nevertheless, I find this elucidation on what is agriculture especially convenient is where its coverage is limited to crop production (agronomy and horticulture) and livestock production even knowing that some definitions include fisheries, forestry, and other activities. Further, the science of agriculture is dynamic.

What is the deliberate effort to modify a portion of Earth’s surface through the cultivation of crops and the raising of

3. Agriculture is the deliberate effort to modify a portion of Earth’s surface through the cultivation of crops and the raising of livestock for sustenance or economic gain. (Rubenstein, J.M. 2003. The Cultural Landscape: An Introduction to Human Geography. 7th ed. Upper Saddle River, NJ: Pearson Education, Inc. p. 496).

What does “agricult” mean?

ag′ri-kult-ūr, n. the art or practice of cultivating the land. — adj. Agricult′ural, relating to agriculture.— n. Agricult′urist, one skilled in agriculture: a farmer—also Agricult′uralist. [L. agricultura — ager, a field, cultura, cultivation. See Culture .]

Why is agriculture important?

Agriculture is an important facet and sector of society as they create the largest amount of food.

What is soil science?

The science of soil cultivation, crop production, and livestock raising.

What is the science of cultivating the ground?

The art or science of cultivating the ground, including the harvesting of crops, and the rearing and management of livestock; tillage; husbandry; farming.

What does “agricultural” mean?

English Language Learners Definition of agricultural. : of, relating to, or used in farming or agriculture. : engaged in or concerned with farming or agriculture. See the full definition for agricultural in the English Language Learners Dictionary.

What are some examples of agricultural?

Recent Examples on the Web Shasta Lake, California’s largest reservoir and third-largest water body overall, represents a crucial water source for agricultural lands in the middle of the state. …

Can flooding affect agricultural land?

Minor flooding can affect some low areas, crossings and agricultural lands, according to the Weather Service. — Michael Williams, Dallas News, 3 June 2021 The Agriculture Department’s new Climate-Smart Practice Incentive will support wetland restoration on agricultural lands.

What is the term for a crop that can be grown for one season?

Auxin, a growth hormone, has been indicated to be involved in the process. Arable crop : A crop that can be grown for one season. Awn : A fine bristle terminating an organ, as found in the flowers of grasses. Axillary : Arising from axil.

What does “curing” mean in agriculture?

Curing : To prepare crops for preservation by drying or other processes.

What is a bulb in plants?

Bulb : An underground storage organ with a much-shortened stem bearing fleshly leaf bases or scale leaves enclosing the next year’s bud. Bulbil : An aerial bulb or bud produced in a leaf axils or replacing the flower, which on separation, is capable of propagating the plant.

Is agriculture a science?

Agriculture is a broad field of science and there are terminologies used in the field of agriculture. Some are pertinent to farming while others to other sub-fields of agric science. Some of the words associated with farming and agriculture generally are discussed in this article. These agriculture vocabularies are listed from A to Z …

Overview

Environmental impact

Etymology and scope

History

Types

Contemporary agriculture

Production

Crop alteration and biotechnology

Asked by: Mckayla Emmerich

Score: 4.5/5
(51 votes)

: the science, art, or practice of cultivating the soil, producing crops, and raising livestock and in varying degrees the preparation and marketing of the resulting products cleared the land to use it for agriculture.

Does the word agriculture mean farming?

By its dictionary definition, agriculture is “farming; the science, art, or occupation concerned with cultivating land, raising crops, and feeding, breeding, and raising livestock.” Since only 1.3 percent of American jobs are farming, and 10.9 percent of American jobs are agriculture and its related industries, I think …

What is the origin of the word agriculture?

The English word agriculture derives from the Latin ager (field) and colo (cultivate) signifying, when combined, the Latin agricultura: field or land tillage.

Does agriculture mean food?

Agriculture is the process of producing food, feed, fiber and many other desired products by the cultivation of certain plants and the raising of domesticated animals (livestock). … Modern agriculture extends well beyond the traditional production of food for humans and animal feeds.

What does the Spanish word agri mean in agriculture?

1. The definition of agri means field or related to the land. An example of agri used as a prefix is in the word agricultural which means related to the culture and cultivating of the land.

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Agriculture (also called farming or husbandry) is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life.^[1] Agriculture was the key implement 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. Agriculture is also observed in certain species of ant and termite,^[2][3] but generally speaking refers to human activities.

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 suitable for raising domesticated species. For plants, this usually requires some form of irrigation, although there are methods of dryland farming; pastoral herding on rangeland is still the most common means of raising livestock. 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 (e.g. permaculture or organic agriculture).

Modern agronomy, plant breeding, 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.^[4] Selective breeding and modern practices in animal husbandry such as intensive pig farming have similarly increased the output of meat, but have raised concerns about animal cruelty and the health effects of the antibiotics, growth hormones, and other chemicals commonly used in industrial meat production.^[5]

The major agricultural products can be broadly grouped into foods, fibers, fuels, and raw materials. In the 21st century, plants have been used to grow biofuels, biopharmaceuticals, bioplastics,^[6] and pharmaceuticals.^[7] Specific foods include cereals, vegetables, fruits, and meat. Fibers include cotton, wool, hemp, silk and flax. Raw materials include lumber and bamboo. Other useful materials are produced by plants, such as resins. Biofuels include methane from biomass, ethanol, and biodiesel. Cut flowers, nursery plants, tropical fish and birds for the pet trade are some of the ornamental products. Regarding food production, the World Bank targets agricultural food production and water management as an increasingly global issue that is fostering an important and growing debate.^[8]

In 2007, one third of the world’s workers were employed in agriculture. The services sector has overtaken agriculture as the economic sector employing the most people worldwide.^[9] Despite the size of its workforce, agricultural production accounts for less than five percent of the gross world product (an aggregate of all gross domestic products).

Etymology

The word agriculture is the English adaptation of Latin agricultūra, from ager, «a field»,^[10] and cultūra, «cultivation» in the strict sense of «tillage of the soil».^[11] Thus, a literal reading of the word yields «tillage of a field / of fields».

Overview

Agriculture has played a key role in the development of human civilization. Until the Industrial Revolution, the vast majority of the human population labored in agriculture. The type of agriculture they developed was typically subsistence agriculture in which farmers raised most of their crops for consumption on farm, and there was only a small portion left over for the payment of taxes, dues, or trade. In subsistence agriculture cropping decisions are made with an eye to what the family needs for food, and to make clothing, and not the world marketplace. Development of agricultural techniques has steadily increased agricultural productivity, and the widespread diffusion of these techniques during a time period is often called an agricultural revolution. 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 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 necessary.

Synthetic nitrogen, along with mined rock phosphate, pesticides and mechanization, have greatly increased crop yields in the early 20th century. Increased supply of grains has led to cheaper livestock as well. Further, global yield increases were experienced later in the 20th century when high-yield varieties of common staple grains such as rice, wheat, and corn (maize) were introduced as a part of the Green Revolution. The Green Revolution exported the technologies (including pesticides and synthetic nitrogen) of the developed world to the developing world. Thomas Malthus famously predicted that the Earth would not be able to support its growing population, but technologies such as the Green Revolution have allowed the world to produce a surplus of food.^[12]

Many governments have subsidized agriculture to ensure an adequate food supply. These agricultural subsidies are often linked to the production of certain commodities such as wheat, corn (maize), rice, soybeans, and milk. These subsidies, especially when instituted by developed countries have been noted as protectionist, inefficient, and environmentally damaging.^[13]

In the past century agriculture has been characterized by enhanced productivity, the use of synthetic fertilizers and pesticides, selective breeding, mechanization, water contamination, and farm subsidies. Proponents of organic farming such as Sir Albert Howard argued in the early 20th century that the overuse of pesticides and synthetic fertilizers damages the long-term fertility of the soil. While this feeling lay dormant for decades, as environmental awareness has increased in the 21st century there has been a movement towards sustainable agriculture by some farmers, consumers, and policymakers.

In recent years there has been a backlash against perceived external environmental effects of mainstream agriculture, particularly regarding water pollution,^[14] resulting in the organic movement. 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,^[15] 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 late 2007, several factors pushed up the price of grains consumed by humans as well as used to feed poultry and dairy cows and other cattle, causing higher prices of wheat (up 58%), soybean (up 32%), and maize (up 11%) over the year.^[16][17] Food riots took place in several countries across the world.^[18][19][20] Contributing factors included drought in Australia and elsewhere, increasing demand for grain-fed animal products from the growing middle classes of countries such as China and India, diversion of foodgrain to biofuel production and trade restrictions imposed by several countries.

An epidemic of stem rust on wheat caused by race Ug99 is currently spreading across Africa and into Asia and is causing major concern.^[21][22][23] Approximately 40% of the world’s agricultural land is seriously degraded.^[24] 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.^[25]

History

Agricultural practices such as irrigation, crop rotation, fertilizers, and pesticides were developed long ago, but have made great strides 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 labor in agricultural societies made commonplace specializations rarely seen in hunter-gatherer cultures. So, too, are arts such as epic literature and monumental architecture, as well as codified legal systems. When farmers became capable of producing food beyond the needs of their own families, others in their society were freed to devote themselves to projects other than food acquisition. Historians and anthropologists have long argued that the development of agriculture made civilization possible. The total world population probably never exceeded 15 million inhabitants before the invention of agriculture.^[26]

Ancient origins

The Fertile Crescent of Western Asia, Egypt, and India were sites of the earliest planned sowing and harvesting of plants that had previously been gathered in the wild. Independent development of agriculture occurred in northern and southern China, Africa’s Sahel, New Guinea and several regions of the Americas.^[27] The eight so-called Neolithic founder crops of agriculture appear: first emmer wheat and einkorn wheat, then hulled barley, peas, lentils, bitter vetch, chick peas and flax.

By 7000 BC, small-scale agriculture reached Egypt. From at least 7000 BC the Indian subcontinent saw farming of wheat and barley, as attested by archaeological excavation at Mehrgarh in Balochistan in what is present day Pakistan. By 6000 BC, mid-scale farming was entrenched on the banks of the Nile. This, as irrigation had not yet matured sufficiently. About this time, agriculture was developed independently in the Far East, with rice, rather than wheat, as the primary crop. Chinese and Indonesian farmers went on to domesticate taro and beans including mung, soy and azuki. To complement these new sources of carbohydrates, highly organized net fishing of rivers, lakes and ocean shores in these areas brought in great volumes of essential protein. Collectively, these new methods of farming and fishing inaugurated a human population boom that dwarfed all previous expansions and continues today.

By 5000 BC, the Sumerians had developed core agricultural techniques including large-scale intensive cultivation of land, monocropping, organized irrigation, and the use of a specialized labor force, particularly along the waterway now known as the Shatt al-Arab, from its Persian Gulf delta to the confluence of the Tigris and Euphrates. Domestication of wild aurochs and mouflon into cattle and sheep, respectively, ushered in the large-scale use of animals for food/fiber and as beasts of burden. The shepherd joined the farmer as an essential provider for sedentary and seminomadic societies. Maize, manioc, and arrowroot were first domesticated in the Americas as far back as 5200 BC.^[28]

The potato, tomato, pepper, squash, several varieties of bean, tobacco, and several other plants were also developed in the Americas, as was extensive terracing of steep hillsides in much of Andean South America. The Greeks and Romans built on techniques pioneered by the Sumerians, but made few fundamentally new advances. Southern Greeks struggled with very poor soils, yet managed to become a dominant society for years. The Romans were noted for an emphasis on the cultivation of crops for trade.

In the same region, a parallel agricultural revolution occurred, resulting in some of the most important crops grown today. In Mesoamerica wild teosinte was transformed through human selection into the ancestor of modern maize, more than 6000 years ago. It gradually spread across North America and was the major crop of Native Americans at the time of European exploration.^[29] Other Mesoamerican crops include hundreds of varieties of squash and beans. Cocoa was also a major crop in domesticated Mexico and Central America. The turkey, one of the most important meat birds, was probably domesticated in Mexico or the U.S. Southwest. In the Andes region of South America the major domesticated crop was potatoes, domesticated perhaps 5000 years ago. Large varieties of beans were domesticated, in South America, as well as animals, including llamas, alpacas, and guinea pigs. Coca, still a major crop, was also domesticated in the Andes.

A minor center of domestication, the indigenous people of the Eastern U.S. appear to have domesticated numerous crops. Sunflowers, tobacco,^[30] varieties of squash and Chenopodium, as well as crops no longer grown, including marshelder and little barley were domesticated.^[31][32] Other wild foods may have undergone some selective cultivation, including wild rice and maple sugar. The most common varieties of strawberry were domesticated from Eastern North America.^[33]

By 3500 BC, the simplest form of the plough was developed, called the ard.^[34] 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, through excavations in Mexico it has been found that the continuous cultivating of smaller pieces of land would also have been a sustaining practice. Additional research in central Europe later revealed that agriculture was indeed practiced at this method. For this method, ards were thus much more efficient than digging sticks.^[35]

Middle Ages

During the Middle Ages, farmers in North Africa, the Near East, and Europe began making use of agricultural technologies including irrigation systems based on hydraulic and hydrostatic principles, machines such as norias, water-raising machines, dams, and reservoirs. This combined with the invention of a three-field system of crop rotation and the moldboard plow greatly improved agricultural efficiency.

In the European medieval period, agriculture was considered part of the set of seven mechanical arts.

Modern era

After 1492, a global exchange of previously local crops and livestock breeds occurred. Key crops involved in this exchange included the tomato, maize, potato, manioc, cocoa bean and tobacco going from the New World to the Old, and several varieties of wheat, spices, coffee, and sugar cane going from the Old World to the New. The most important animal exportation from the Old World to the New were those of the horse and dog (dogs were already present in the pre-Columbian Americas but not in the numbers and breeds suited to farm work). Although not usually food animals, the horse (including donkeys and ponies) and dog quickly filled essential production roles on western-hemisphere farms.

The potato became an important staple crop in northern Europe.^[36] Since being introduced by Portuguese in the 16th century,^[37] maize and manioc have replaced traditional African crops as the continent’s most important staple food crops.^[38]

By the early 19th century, agricultural techniques, implements, seed stocks and cultivar had so improved that yield per land unit was many times that seen in the Middle Ages. Although there is a vast and interesting history of crop cultivation before the dawn of the 20th century, there is little question that the work of Charles Darwin and Gregor Mendel created the scientific foundation for plant breeding that led to its explosive impact over the past 150 years.^[39]

With the rapid rise of mechanization in the late 19th century and the 20th century, particularly in the form of the tractor, farming tasks could be done with a speed and on a scale previously impossible. These advances have led to efficiencies enabling certain modern farms in the United States, Argentina, Israel, the United Kingdom Germany, and a few other nations to output volumes of high-quality produce per land unit at what may be the practical limit.

The Haber-Bosch method for synthesizing ammonium nitrate represented a major breakthrough and allowed crop yields to overcome previous constraints. In the past century agriculture has been characterized by enhanced 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 movement.

The cereals rice, corn, and wheat provide 60% of human food supply.^[40] 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.^[40] For example, irrigation increased corn yields in eastern Colorado by 400 to 500% from 1940 to 1997.^[40]

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.^[40]

Although the «Green Revolution» significantly increased rice yields in Asia, yield increases have not occurred in the past 15–20 years.^[41] 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».^[41] It takes a decade or two for herbicide-resistant weeds to emerge, and insects become resistant to insecticides within about a decade.^[41] Crop rotation helps to prevent resistances.^[41]

Agricultural exploration expeditions, since the late 19th century, have been mounted to find new species and new agricultural practices in different areas of the world. Two early examples of expeditions include Frank N. Meyer’s fruit- and nut-collecting trip to China and Japan from 1916-1918^[42] and the Dorsett-Morse Oriental Agricultural Exploration Expedition to China, Japan, and Korea from 1929-1931 to collect soybean germplasm to support the rise in soybean agriculture in the United States.^[43]

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 2.6 times more productive than it was in 1948.^[44]

Six countries — the US, Canada, France, Australia, Argentina and Thailand — supply 90% of grain exports.^[45] Water deficits, which are already spurring heavy grain imports in numerous middle-sized countries, including Algeria, Iran, Egypt, and Mexico,^[46] may soon do the same in larger countries, such as China or India.^[47]

Crop production 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.^[48][49] 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.^[50]

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 lead 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.^[49] 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.^[50]

In tropical environments, all of these cropping systems are practiced. 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.^[50]

The last century has seen the intensification, concentration and specialization of agriculture, relying upon new technologies of agricultural chemicals (fertilizers and pesticides), mechanization, and plant breeding (hybrids and GMO’s). In the past few decades, a move towards sustainability in agriculture has also developed, integrating ideas of socio-economic justice and conservation of resources and the environment within a farming system.^[51][52] This has led to the development of many responses to the conventional agriculture approach, including organic agriculture, urban agriculture, community supported agriculture, ecological or biological agriculture, integrated farming and holistic management, as well as an increased trend towards agricultural diversification.

Crop statistics

Important categories of crops include grains and pseudograins, 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.

Livestock production systems

Animals, including horses, mules, oxen, camels, llamas, alpacas, 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.^[54]

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.^[50] Mixed production systems use grassland, fodder crops and grain feed crops as feed for ruminant and monogastic (one stomach; mainly chickens and pigs) livestock. Manure is typically recycled in mixed systems as a fertilizer for crops. Approximately 68% of all agricultural land is permanent pastures used in the production of livestock.^[55]

Landless systems rely upon feed from outside the farm, representing the de-linking of crop and livestock production found more prevalently in OECD member countries. In the U.S., 70% of the grain grown is fed to animals on feedlots.^[50] Synthetic fertilizers are more heavily relied upon for crop production and manure utilization becomes a challenge as well as a source for pollution.

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.^[56][57]

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.^[58]

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.^[59] Crop nutrient use may also be managed using cultural techniques such as crop rotation or a fallow period.^[60][61] 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 where rainfall is insufficient or variable, which occurs to some degree in most regions of the world.^[50] 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.^[62] Agriculture represents 70% of freshwater use worldwide.^[63]

Processing, distribution, and marketing

Main article: Agricultural marketing

In the United States, food costs attributed to processing, distribution, and marketing 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. From 1960 to 1980 the farm share was around 40%, but by 1990 it had declined to 30% and by 1998, 22.2%. Market concentration has increased in the sector as well, with the top 20 food manufacturers accounting for half the food-processing value in 1995, over double that produced in 1954. As of 2000 the top six US supermarket groups had 50% of sales compared to 32% in 1992. 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.^[64]

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 gave plant breeders a better understanding of genetics and brought great insights to the techniques utilized by plant breeders. Crop breeding includes techniques such as plant selection with desirable traits, self-pollination and cross-pollination, and molecular techniques that genetically modify the organism.^[65]

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.^[66][67]

The Green Revolution popularized the use of conventional hybridization to increase yield many folds 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, 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).^[68][69][70]

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. After mechanical tomato-harvesters were developed in the early 1960s, agricultural scientists genetically modified tomatoes to be more resistant to mechanical handling. More recently, genetic engineering is being employed in various parts of the world, to create crops with other beneficial traits. New research on woodland strawberry genome was found to be short and easy to manipulate. Researchers now have tools to improve strawberry flavors and aromas of cultivated strawberries as stated in a publication by Nature Genetics. http://www.isaaa.org/kc/cropbiotechupdate/article/default.asp?ID=7160

Herbicide-tolerant GMO crops

Roundup Ready seed has a herbicide resistant gene implanted into its genome that allows the plants to tolerate exposure to glyphosate. Roundup is a trade name for a glyphosate-based product, which is a systemic, nonselective herbicide used to kill weeds. Roundup Ready seeds allow the farmer to grow a crop that can be sprayed with glyphosate to control weeds without harming the resistant crop. Herbicide-tolerant crops are used by farmers worldwide. Today, 92% of soybean acreage in the US is planted with genetically modified herbicide-tolerant plants.^[71]

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.^[72][73] 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.^[74]

Insect-resistant GMO crops

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; one such crop is Starlink. Another is cotton, which accounts for 63% of US cotton acreage.^[75]

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.^[76]

Costs and benefits of GMOs

Genetic engineers may someday develop transgenic plants which would allow for irrigation, drainage, conservation, sanitary engineering, and maintaining or increasing yields while requiring fewer fossil fuel derived inputs than conventional crops. Such developments would be particularly important in areas which are normally arid and rely upon constant irrigation, and on large scale farms. However, genetic engineering of plants has proven to be controversial. Many issues surrounding food security and environmental impacts have risen regarding GMO practices. For example, GMOs are questioned by some ecologists and economists concerned with GMO practices such as terminator seeds,^[77][78] which is a genetic modification that creates sterile seeds. Terminator seeds are currently under strong international opposition and face continual efforts of global bans.^[79]

Another controversial issue is the patent protection given to companies that develop new types of seed using genetic engineering. Since companies have intellectual ownership of their seeds, they have the power to dictate terms and conditions of their patented product. Currently, ten seed companies control over two-thirds of the global seed sales.^[80] Vandana Shiva argues that these companies are guilty of biopiracy by patenting life and exploiting organisms for profit^[81] Farmers using patented seed are restricted from saving seed for subsequent plantings, which forces farmers to buy new seed every year. Since seed saving is a traditional practice for many farmers in both developing and developed countries, GMO seeds legally bind farmers to change their seed saving practices to buying new seed every year.^[72][81]

Locally adapted seeds are an essential heritage that has the potential to be lost with current hybridized crops and GMOs. Locally adapted seeds, also called land races or crop eco-types, are important because they have adapted over time to the specific microclimates, soils, other environmental conditions, field designs, and ethnic preference indigenous to the exact area of cultivation.^[82] Introducing GMOs and hybridized commercial seed to an area brings the risk of cross-pollination with local land races Therefore, GMOs pose a threat to the sustainability of land races and the ethnic heritage of cultures. Once seed contains transgenic material, it becomes subject to the conditions of the seed company that owns the patent of the transgenic material.^[83]

Modern agriculture

Modern agriculture is a term used to describe the wide majority of production practices employed by America’s farmers. The term depicts the push for innovation, stewardship and advancements continually made by growers to sustainably produce higher-quality products with a reduced environmental impact. Intensive scientific research and robust investment in modern agriculture during the past 50 years has helped farmers double food production.^[84][85]

Safety

The agriculture industry works with government agencies and other organizations to ensure that farmers have access to the technologies required to support modern agriculture practices. Farmers are supported by education and certification programs that ensure they apply agricultural practices with care and only when required.^{[clarification needed]}

Sustainability

Technological advancements help provide farmers with tools and resources to make farming more sustainable.^[86]

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.^[87]

Affordability

The goal of modern agriculture practices is to help farmers provide an affordable supply of food to meet the demands of a growing population.^[88] With modern agriculture, more crops can be grown on less land allowing farmers to provide an increased supply of food at an affordable price.

Food safety, labeling and regulation

Food security issues also coincide with food safety and food labeling concerns. Currently a global treaty, the BioSafety Protocol, regulates the trade of GMOs. The EU currently requires all GMO foods to be labeled, whereas the US does not require transparent labeling of GMO foods. Since there are still questions regarding the safety and risks associated with GMO foods, some believe the public should have the freedom to choose and know what they are eating and require all GMO products to be labeled.^[89]

The Food and Agriculture Organization of the United Nations (FAO) leads international efforts to defeat hunger and provides a neutral forum where nations meet as equals to negotiate agreements and debate food policy and the regulation of agriculture. According to Dr. Samuel Jutzi, director of FAO’s animal production and health division, lobbying by «powerful» big food corporations has stopped reforms that would improve human health and the environment. The «real, true issues are not being addressed by the political process because of the influence of lobbyists, of the true powerful entities,» he said, speaking at the Compassion in World Farming annual forum. For example, recent proposals 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.^[90]

Environmental impact

Main article: Environmental issues with agriculture

Agriculture imposes external costs upon society through pesticides, nutrient runoff, excessive water usage, 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.^[91] 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.^[92] Both studies concluded that more should be done to internalize external costs, and neither included subsidies in their analysis, but noted that subsidies also influence the cost of agriculture to society. Both focused on purely fiscal impacts. The 2000 review included reported pesticide poisonings but did not include speculative chronic effects of pesticides, and the 2004 review relied on a 1992 estimate of the total impact of pesticides.

In 2010, the International Resource Panel of the United Nations Environment Programme published a report 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.^[93]

Agriculture accounts for 70 per cent of withdrawals of freshwater resources.^[94] However, increasing pressure being placed on water resources by industry, cities and the involving biofuels industry means that water scarcity is increasing and agriculture is facing the challenge of producing more food for the world’s growing population with fewer water resources. Scientists are also realising that water resources need to be allocated to maintain natural environmental services, such as protecting towns from flooding, cleaning ecosystems and supporting fish stocks. In the book Out of Water: From abundance to scarcity and how to solve the world’s water problems, authors Colin Chartres and Samyukta Varma of the International Water Management Institute lay down a six-point plan of action for addressing the global challenge of producing sufficient food for the world with dwindling water resources. One of the actions they say is required is to ensure all water systems, such as lakes and rivers, have water allocated to environmental flow.^[95]

A key player who is credited to saving billions of lives because of his revolutionary work in developing new agricultural techniques is Norman Borlaug. His transformative work brought high-yield crop varieties to developing countries and earned him an unofficial title as the father of the Green Revolution.

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».^[96] 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 CO_2,) 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.^[97] Through deforestation and land degradation, livestock is also driving reductions in biodiversity.

Land transformation and degradation

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 39–50%.^[98] Land degradation, the long-term decline in ecosystem function and productivity, is estimated to be occurring on 24% of land worldwide, with cropland overrepresented.^[99] 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).^[50]

Eutrophication

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.^[100]

Pesticides

Pesticide use has increased since 1950 to 2.5 million tons annually worldwide, yet crop loss from pests has remained relatively constant.^[101] The World Health Organization estimated in 1992 that 3 million pesticide poisonings occur annually, causing 220,000 deaths.^[102] 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.^[103]

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’.^[104][105] However, critics argue that a trade-off between the environment and a need for food is not inevitable,^[106] and that pesticides simply replace good agronomic practices such as crop rotation.^[103]

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.^[50][107] 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.^[108] Further, wet or anaerobic soils also lose nitrogen through denitrification, releasing the greenhouse gases nitric oxide and nitrous oxide.^[109] 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.^[108]

International economics and market reports

Differences in economic development, population density and culture mean that the farmers of the world operate under very different conditions.

A US cotton farmer may receive US$230^[110] in government subsidies per acre planted (in 2003), while farmers in Mali and other third-world countries do without. When prices decline, the heavily subsidized US farmer is not forced to reduce his output, making it difficult for cotton prices to rebound, but his Mali counterpart may go broke in the meantime.

A livestock farmer in South Korea can calculate with a (highly subsidized) sales price of US$1300 for a calf produced.^[111] A South American Mercosur country rancher calculates with a calf’s sales price of US$120–200 (both 2008 figures).^[112] With the former, scarcity and high cost of land is compensated with public subsidies, the latter compensates absence of subsidies with economics of scale and low cost of land.

In the Peoples Republic of China, a rural household’s productive asset may be one hectare of farmland.^[113] In Brazil, Paraguay and other countries where local legislature allows such purchases, international investors buy thousands of hectares of farmland or raw land at prices of a few hundred US$ per hectare.^{[114][115][116]}

To promote exports of agricultural products, many government agencies publish on the web economic studies and reports categorized by product and country. Among these agencies include four of the largest exporters of agricultural products, such as the FAS of the United States Department of Agriculture, Agriculture and Agri-Food Canada (AAFC), Austrade, and NZTE . The Federation of International Trade Associations publishes studies and reports by FAS and AAFC, as well as other non-governmental organizations on its website GlobalTrade.net.

List of countries by agricultural output

Below is a list of countries by agricultural output in 2010.

Agricultural output in 2010 (Nominal)

Rank	Country	Output in billions of US$
—	World	3,585.829
1	China	599.582
—	European Union	293.080
2	India	284.524
3	United States	161.236
4	Brazil	142.141
5	Indonesia	108.130
6	Japan	76.424
7	Turkey	71.218
8	Nigeria	65.041
9	Russia	58.603
10	France	51.651

Agricultural output in 2010 (PPP)

Rank	Country	Output in billions of US$
—	World	4,233.098
1	China	1,028.742
2	India	751.173
—	European Union	273.068
3	United States	161.236
4	Indonesia	157.572
5	Brazil	147.700
6	Nigeria	113.385
7	Pakistan	101.348
8	Turkey	92.209
9	Iran	90.052
10	Russia	88.918

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.^[117] Between 1950 and 1984, the Green Revolution transformed agriculture around the globe, with world grain production increasing by 250%^[118][119] 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[120]	2005	1.9	11
United States of America[121]	1996	2.1	10
United States of America[122]	2002	2.0	14
Sweden[123]	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 gas, 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 percent of the nation’s total energy.^[124]

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.^[124] The energy used to manufacture farm machinery is also a form of indirect agricultural energy consumption, but it is not included in USDA estimates of U.S. agricultural energy use. Together, direct and indirect consumption by U.S. farms accounts for about 2 percent 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.^[124]

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 United States.^[121][122]

In 2007, higher incentives for farmers to grow non-food biofuel crops^[125] combined with other factors (such as over-development of former farm lands, rising transportation costs, climate change, growing consumer demand in China and India, and population growth)^[126] to cause food shortages in Asia, the Middle East, Africa, and Mexico, as well as rising food prices around the globe.^[127][128] 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.^[18][19][20]

The biggest fossil fuel input to agriculture is the use of natural gas as a hydrogen source for the Haber-Bosch fertilizer-creation process.^[129] Natural gas is used because it is the cheapest currently available source of hydrogen.^[130][131] When oil production becomes so scarce that natural gas is used as a partial stopgap replacement, and hydrogen use in transportation increases, natural gas will become much more expensive. If the Haber Process is unable to be commercialized using renewable energy (such as by electrolysis) or if other sources of hydrogen are not available to replace the Haber Process, in amounts sufficient to supply transportation and agricultural needs, this major source of fertilizer would either become extremely expensive or unavailable. This would either cause food shortages or dramatic rises in food prices.^{[citation needed]}

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 farmers using modern organic-farming methods have reported yields as high as those available from conventional farming.^{[132][133][134][135]} Organic farming may however be more labor-intensive and would require a shift of the workforce from urban to rural areas.^[136] The reconditioning of soil to restore nutrients lost during the use of monoculture agriculture techniques also takes time.^{[132][133][134][135]}

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.^[137][138]

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.^[139] The possibility of success of these programs is questioned by ecologists and economists concerned with unsustainable GMO practices such as terminator seeds.^[140][141]

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.^[142]

Electrical energy efficiency on farms

Main article: Electrical energy efficiency on United States farms

Policy

Agricultural policy focuses on the goals and methods of agricultural production. At the policy level, common goals of agriculture include:

• Conservation
• Economic stability
• Environmental sustainability
• Food quality: Ensuring that the food supply is of a consistent and known quality.
• Food safety: Ensuring that the food supply is free of contamination.
• Food security: Ensuring that the food supply meets the population’s needs.^[143][144]
• Poverty reduction

See also

Lists

• List of basic agriculture topics
• List of countries by GDP sector composition — breakdown includes agricultural sector information
• List of largest producing countries of agricultural commodities
• List of countries by dietary calorie intake
• List of domesticated animals
• List of subsistence techniques
• List of sustainable agriculture topics

References

Bibliography

External links

• Agriculture from UCB Libraries GovPubs
• Agriculture and Rural development from the World Bank
• The World Bank on Agricultural water management
• Gender in agriculture and rural development (FAO)
• Index to the Manuscript Collections Special Collections, National Agricultural Library
• The American Society of Agronomy (ASA)
• International Federation of Agricultural Producers (IFAP)
• NIOSH Agriculture Page — safety laws, tips, and guidelines
• U.S. House Committee on Agriculture — Glossary of agricultural terms, programs and laws
• UKAgriculture.com — Advance the education of the public in all aspects of agriculture, the countryside and the rural economy
• Guide to collections containing information on agriculture at the Eisenhower Presidential Library
• Collection of Agriculture Dictionaries

Farmer Power: The Continuing Confrontation between Subsistence Farmers and Development Bureaucrats by Tony Waters at Ethnography.com [4]