Intensive farming involves various types of agriculture with higher levels of input and output per cubic unit of agricultural land area. It is characterized by a low fallow ratio, higher use of inputs such as capital and labour, and higher crop yields per cubic unit land area. This contrasts with traditional agriculture, in which the inputs per unit land are lower. The term "intensive" involves various meanings, some of which refer to organic farming methods (such as biointensive agriculture and French intensive gardening), and others that refer to nonorganic and industrial methods. Intensive animal farming involves either large numbers of animals raised on limited land, usually confined animal feeding operations (CAFOs), often referred to as factory farms, or managed intensive rotational grazing (MIRG), which has both organic and non-organic types. Both increase the yields of food and fiber per acre as compared to traditional animal husbandry. In CAFO, feed is brought to the seldom-moved animals, while in MIRG the animals are repeatedly moved to fresh forage.
Most commercial agriculture is intensive in one or more ways. Forms that rely heavily on industrial methods are often called industrial agriculture, which is characterised by innovations designed to increase yield. Techniques include planting multiple crops per year, reducing the frequency of fallow years, and improving cultivars. It also involves increased use of fertilizers, plant growth regulators, and pesticides and mechanised agriculture, controlled by increased and more detailed analysis of growing conditions, including weather, soil, water, weeds, and pests. This system is supported by ongoing innovation in agricultural machinery and farming methods, genetic technology, techniques for achieving economies of scale, logistics, and data collection and analysis technology. Intensive farms are widespread in developed nations and increasingly prevalent worldwide. Most of the meat, dairy, eggs, fruits, and vegetables available in supermarkets are produced by such farms.
Smaller intensive farms usually include higher inputs of labor and more often use sustainable intensive methods. The farming practices commonly found on such farms are referred to as appropriate technology. These farms are less widespread in both developed countries and worldwide, but are growing more rapidly. Most of the food available in specialty markets such as farmers markets is produced by these small holder farms.
Main articles: Agriculture § Modern developments, and British Agricultural Revolution
Agricultural development in Britain between the 16th century and the mid-19th century saw a massive increase in agricultural productivity and net output. This in turn supported unprecedented population growth, freeing up a significant percentage of the workforce, and thereby helped enable the Industrial Revolution. Historians cited enclosure, mechanization, four-field crop rotation, and selective breeding as the most important innovations.
Industrial agriculture arose along with the Industrial Revolution. By the early 19th century, agricultural techniques, implements, seed stocks, and cultivars had so improved that yield per land unit was many times that seen in the Middle Ages.
The industrialization phase involved a continuing process of mechanization. Horse-drawn machinery such as the McCormick reaper revolutionized harvesting, while inventions such as the cotton gin reduced the cost of processing. During this same period, farmers began to use steam-poweredthreshers and tractors, although they were expensive and dangerous. In 1892, the first gasoline-powered tractor was successfully developed, and in 1923, the International HarvesterFarmall tractor became the first all-purpose tractor, marking an inflection point in the replacement of draft animals with machines. Mechanical harvesters (combines), planters, transplanters, and other equipment were then developed, further revolutionizing agriculture. These inventions increased yields and allowed individual farmers to manage increasingly large farms.
The identification of nitrogen, phosphorus, and potassium (NPK) as critical factors in plant growth led to the manufacture of synthetic fertilizers, further increasing crop yields. In 1909, the Haber-Bosch method to synthesize ammonium nitrate was first demonstrated. NPK fertilizers stimulated the first concerns about industrial agriculture, due to concerns that they came with serious side effects such as soil compaction, soil erosion, and declines in overall soil fertility, along with health concerns about toxic chemicals entering the food supply.
The identification of carbon as a critical factor in plant growth and soil health, particularly in the form of humus, led to so-called sustainable agriculture, as well as alternative forms of intensive agriculture that also surpassed traditional agriculture, without side effects or health issues. Farmers adopting this approach were initially referred to as humus farmers, later as organic farmers.
The discovery of vitamins and their role in nutrition, in the first two decades of the 20th century, led to vitamin supplements, which in the 1920s allowed some livestock to be raised indoors, reducing their exposure to adverse natural elements. Chemicals developed for use in World War II gave rise to synthetic pesticides.
Following World War II, synthetic fertilizer use increased rapidly, while sustainable intensive farming advanced much more slowly. Most of the resources in developed nations went to improving industrial intensive farming, and very little went to improving organic farming. Thus, particularly in the developed nations, industrial intensive farming grew to become the dominant form of agriculture.
The discovery of antibiotics and vaccines facilitated raising livestock in confined animal feeding operations by reducing diseases caused by crowding. Developments in logistics and refrigeration as well as processing technology made long-distance distribution feasible.
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. Global agricultural production doubled between 1820 and 1920; between 1920 and 1950; between 1950 and 1965; and again between 1965 and 1975 to feed a global population that grew from one billion in 1800 to 6.5 billion in 2002.:29 The number of people involved in farming in industrial countries dropped, from 24 percent of the American population to 1.5 percent in 2002. In 1940, each farmworker supplied 11 consumers, whereas in 2002, each worker supplied 90 consumers.:29 The number of farms also decreased and their ownership became more concentrated. In the year 2000 in the U.S., four companies produced 81 percent of cows, 73 percent of sheep, 57 percent of pigs, and 50 percent of chickens, which was cited as an example of "vertical integration" by the president of the U.S. National Farmers Union. Between 1967 and 2002, the one million pig farms in America consolidated into 114,000:29, with 80 million pigs (out of 95 million) produced each year on factory farms, according to the U.S. National Pork Producers Council.:29 According to the Worldwatch Institute, 74 percent of the world's poultry, 43 percent of beef, and 68 percent of eggs are produced this way.:26
Concerns over the sustainability of industrial agriculture, which has become associated with decreasedsoil quality, and over the environmental effects of fertilizers and pesticides, have not subsided. Alternatives such as integrated pest management (IPM) have had little impact because policies encourage the use of pesticides and IPM is knowledge-intensive. These concerns sustained the organic movement and caused a resurgence in sustainable intensive farming, as well as funding for the development of appropriate technology.
Famines continued throughout the 20th century. Through the effects of climactic events, government policy, war, and crop failure, millions of people died in each of at least ten famines between the 1920s and the 1990s.
Techniques and technologies
Main article: Intensive animal farming
Confined animal feeding operations
Intensive livestock farming, also called "factory farming", is a term referring to the process of raising livestock in confinement at high stocking density. "Concentrated animal feeding operations" (CAFO), or "intensive livestock operations", can hold large numbers (some up to hundreds of thousands) of cows, hogs, turkeys, or chickens, often indoors. The essence of such farms is the concentration of livestock in a given space. The aim is to provide maximum output at the lowest possible cost and with the greatest level of food safety. The term is often used pejoratively. However, CAFOs have dramatically increased the production of food from animal husbandry worldwide, both in terms of total food produced and efficiency.
Food and water is delivered to the animals, and therapeutic use of antimicrobial agents, vitamin supplements, and growth hormones are often employed. Growth hormones are not used on chickens nor on any animal in the European Union. Undesirable behaviors often related to the stress of confinement led to a search for docile breeds (e.g., with natural dominant behaviors bred out), physical restraints to stop interaction, such as individual cages for chickens, or physical modification such as the de-beaking of chickens to reduce the harm of fighting.
The CAFO designation resulted from the 1972 U.S. Federal Clean Water Act, which was enacted to protect and restore lakes and rivers to a "fishable, swimmable" quality. The United States Environmental Protection Agency (EPA) identified certain animal feeding operations, along with many other types of industry, as "point source" groundwater polluters. These operations were subjected to regulation.
In 17 states in the U.S., isolated cases of groundwater contamination were linked to CAFOs. For example, the ten million hogs in North Carolina generate 19 million tons of waste per year. The U.S. federal government acknowledges the waste disposal issue and requires that animal waste be stored in lagoons. These lagoons can be as large as 7.5 acres (30,000 m2). Lagoons not protected with an impermeable liner can leak into groundwater under some conditions, as can runoff from manure used as fertilizer. A lagoon that burst in 1995 released 25 million gallons of nitrous sludge in North Carolina's New River. The spill allegedly killed eight to ten million fish.
The large concentration of animals, animal waste, and dead animals in a small space poses ethical issues to some consumers. Animal rights and animal welfare activists have charged that intensive animal rearing is cruel to animals.
Other concerns include persistent noxious odor, the effects on human health, and the role of antibiotic use in the rise of resistant infectious bacteria.
According to the U.S. Centers for Disease Control and Prevention (CDC), farms on which animals are intensively reared can cause adverse health reactions in farm workers. Workers may develop acute and/or chronic lung disease, musculoskeletal injuries, and may catch ( zoonotic) infections from the animals.
Managed intensive rotational grazing
Main article: Managed intensive rotational grazing
Managed Intensive Rotational Grazing (MIRG), also known as cell grazing, mob grazing, and holistic management planned grazing, is a variety of foraging in which herds or flocks are regularly and systematically moved to fresh, rested grazing areas to maximize the quality and quantity of forage growth. MIRG can be used with cattle, sheep, goats, pigs, chickens, turkeys, ducks, and other animals. The herds graze one portion of pasture, or a paddock, while allowing the others to recover. Resting grazed lands allows the vegetation to renew energy reserves, rebuild shoot systems, and deepen root systems, resulting in long-term maximum biomass production. MIRG is especially effective because grazers thrive on the more tender younger plant stems. MIRG also leaves parasites behind to die off, minimizing or eliminating the need for de-wormers. Pasture systems alone can allow grazers to meet their energy requirements, and with the increased productivity of MIRG systems, the animals obtain the majority of their nutritional needs, in some cases all, without the supplemental feed sources that are required in continuous grazing systems.
Main article: Intensive crop farming
The Green Revolution transformed farming in many developing countries. It spread technologies that had already existed, but had not been widely used outside of industrialized nations. These technologies included "miracle seeds", pesticides, irrigation, and synthetic nitrogen fertilizer.
In the 1970s, scientists created strains of maize, wheat, and rice that are generally referred to as high-yielding varieties (HYV). HYVs have an increased nitrogen-absorbing potential compared to other varieties. Since cereals that absorbed extra nitrogen would typically lodge (fall over) before harvest, semi-dwarfing genes were bred into their genomes. Norin 10 wheat, a variety developed by Orville Vogel from Japanese dwarf wheat varieties, was instrumental in developing wheat cultivars. IR8, the first widely implemented HYV rice to be developed by the International Rice Research Institute, was created through a cross between an Indonesian variety named “Peta” and a Chinese variety named “Dee Geo Woo Gen.”
With the availability of molecular genetics in Arabidopsis and rice the mutant genes responsible (reduced height (rht), gibberellin insensitive (gai1) and slender rice (slr1)) have been cloned and identified as cellular signalling components of gibberellic acid, a phytohormone involved in regulating stem growth via its effect on cell division. Photosynthetic investment in the stem is reduced dramatically as the shorter plants are inherently more mechanically stable. Nutrients become redirected to grain production, amplifying in particular the yield effect of chemical fertilizers.
HYVs significantly outperform traditional varieties in the presence of adequate irrigation, pesticides, and fertilizers. In the absence of these inputs, traditional varieties may outperform HYVs. They were developed as F1 hybrids, meaning seeds need to be purchased every season to obtain maximum benefit, thus increasing costs.
Main article: Crop rotation
Crop rotation or crop sequencing is the practice of growing a series of dissimilar types of crops in the same space in sequential seasons for benefits such as avoiding pathogen and pest buildup that occurs when one species is continuously cropped. Crop rotation also seeks to balance the nutrient demands of various crops to avoid soil nutrient depletion. A traditional component of crop rotation is the replenishment of nitrogen through the use of legumes and green manure in sequence with cereals and other crops. Crop rotation can also improve soil structure and fertility by alternating deep-rooted and shallow-rooted plants. A related technique is to plant multi-species cover crops between commercial crops. This combines the advantages of intensive farming with continuous cover and polyculture.
Main article: Irrigation
Crop irrigation accounts for 70% of the world's fresh water use.
Flood irrigation, the oldest and most common type, is typically unevenly distributed, as parts of a field may receive excess water in order to deliver sufficient quantities to other parts. Overhead irrigation, using center-pivot or lateral-moving sprinklers, gives a much more equal and controlled distribution pattern. Drip irrigation is the most expensive and least-used type, but delivers water to plant roots with minimal losses.
Water catchment management measures include recharge pits, which capture rainwater and runoff and use it to recharge groundwater supplies. This helps in the replenishment of groundwater wells and eventually reduces soil erosion. Dammed rivers creating reservoirs store water for irrigation and other uses over large areas. Smaller areas sometimes use irrigation ponds or groundwater.
Main article: Weed control
In agriculture, systematic weed management is usually required, often performed by machines such as cultivators or liquid herbicide sprayers. Herbicides kill specific targets while leaving the crop relatively unharmed. Some of these act by interfering with the growth of the weed and are often based on plant hormones. Weed control through herbicide is made more difficult when the weeds become resistant to the herbicide. Solutions include:
- Cover crops (especially those with allelopathic properties) that out-compete weeds or inhibit their regeneration
- Multiple herbicides, in combination or in rotation
- Strains genetically engineered for herbicide tolerance
- Locally adapted strains that tolerate or out-compete weeds
- Ground cover such as mulch or plastic
- Manual removal
Main article: Terrace (agriculture)
In agriculture, a terrace is a leveled section of a hilly cultivated area, designed as a method of soil conservation to slow or prevent the rapid surface runoff of irrigation water. Often such land is formed into multiple terraces, giving a stepped appearance. The human landscapes of rice cultivation in terraces that follow the natural contours of the escarpments, like contour ploughing, are a classic feature of the island of Bali and the Banaue Rice Terraces in Banaue, Ifugao, Philippines. In Peru, the Inca made use of otherwise unusable slopes by building drystone walls to create terraces.
Main article: Paddy field
A paddy field is a flooded parcel of arable land used for growing rice and other semiaquatic crops. Paddy fields are a typical feature of rice-growing countries of east and southeast Asia, including Malaysia, China, Sri Lanka, Myanmar, Thailand, Korea, Japan, Vietnam, Taiwan, Indonesia, India, and the Philippines. They are also found in other rice-growing regions such as Piedmont (Italy), the Camargue (France), and the Artibonite Valley (Haiti). They can occur naturally along rivers or marshes, or can be constructed, even on hillsides. They require large water quantities for irrigation, much of it from flooding. It gives an environment favourable to the strain of rice being grown, and is hostile to many species of weeds. As the only draft animal species which is comfortable in wetlands, the water buffalo is in widespread use in Asian rice paddies.
Paddy-based rice-farming has been practiced in Korea since ancient times. A pit-house at the Daecheon-ni archaeological site yielded carbonized rice grains and radiocarbon dates indicating that rice cultivation may have begun as early as the Middle Jeulmun Pottery Period (c. 3500–2000 BC) in the Korean Peninsula. The earliest rice cultivation there may have used dry-fields instead of paddies.
The earliest Mumun features were usually located in naturally swampy, low-lying narrow gulleys and fed by local streams. Some Mumun paddies in flat areas were made of a series of squares and rectangles separated by bunds approximately 10 cm in height, while terraced paddies were long and irregular in shape, following the natural contours of the land at various levels.
Like today, Mumun period rice farmers used terracing, bunds, canals, and small reservoirs. Some paddy-farming techniques of the Middle Mumun period (c. 850–550 BC) can be interpreted from the well-preserved wooden tools excavated from archaeological rice paddies at the Majeon-ni site. Iron tools for paddy-farming were not introduced until sometime after 200 BC. The spatial scale of individual paddies, and thus entire paddy-fields, increased with the regular use of iron tools in the Three Kingdoms of Korea Period (c. AD 300/400–668).
A recent development in the intensive production of rice is System of Rice Intensification (SRI). Developed in 1983 by the FrenchJesuitFatherHenri de Laulanié in Madagascar, by 2013 the number of smallholder farmers using SRI had grown to between 4 and 5 million.
Main article: Aquaculture
Aquaculture is the cultivation of the natural products of water (fish, shellfish, algae, seaweed, and other aquatic organisms). Intensive aquaculture takes place on land using tanks, ponds, or other controlled systems, or in the ocean, using cages.
Sustainable intensive farming
Further information: Sustainable farming, Integrated Multi-Trophic Aquaculture, Zero waste agriculture, and Organic farming
Sustainable intensive farming practices have been developed to slow the deterioration of agricultural land and even regenerate soil health and ecosystem services, while still offering high yields. Most of these developments fall in the category of organic farming, or the integration of organic and conventional agriculture.
"Organic systems and the practices that make them effective are being picked up more and more by conventional agriculture and will become the foundation for future farming systems. They won't be called organic, because they'll still use some chemicals and still use some fertilizers, but they'll function much more like today's organic systems than today's conventional systems."
Dr. Charles Benbrook Executive director US House Agriculture Subcommittee Director Agricultural Board - National Academy Sciences (FMR)
The System of Crop Intensification (SCI) was born out of research primarily at Cornell University and smallholder farms in India on SRI. It uses the SRI concepts and methods for rice and applies them to crops like wheat, sugarcane, finger millet, and others. It can be 100% organic, or integrated with reduced conventional inputs.
Holistic management is a systems thinking approach that was originally developed for reversing desertification. Holistic planned grazing is similar to rotational grazing but differs in that it more explicitly provides a framework for adapting to four basic ecosystem processes: the water cycle, the mineral cycle (including the carbon cycle),energy flow, and community dynamics (the relationship between organisms in an ecosystem) as equal in importance to livestock production and social welfare. By intensively managing the behavior and movement of livestock, holistic planned grazing simultaneously increases stocking rates and restores grazing land.
Pasture cropping involves planting grain crops directly into grassland without first applying herbicides. The perennial grasses form a living mulch understory to the grain crop, eliminating the need to plant cover crops after harvest. The pasture is intensively grazed both before and after grain production using holistic planned grazing. This intensive system yields equivalent farmer profits (partly from increased livestock forage) while building new topsoil and sequestering up to 33 tons of CO2/ha/year.
The Twelve Aprils grazing program for dairy production, developed in partnership with the USDA-SARE, is similar to pasture cropping, but the crops planted into the perennial pasture are forage crops for dairy herds. This system improves milk production and is more sustainable than confinement dairy production.
Integrated multi-trophic aquaculture (IMTA) is an example of a holistic approach. IMTA is a practice in which the by-products (wastes) from one species are recycled to become inputs (fertilizers, food) for another. Fed aquaculture (e.g. fish, shrimp) is combined with inorganic extractive (e.g. seaweed) and organic extractive aquaculture (e.g. shellfish) to create balanced systems for environmental sustainability (biomitigation), economic stability (product diversification and risk reduction), and social acceptability (better management practices).
Biointensive agriculture focuses on maximizing efficiency such as per unit area, energy input, and water input. Agroforestry combines agriculture and orchard/forestry technologies to create more integrated, diverse, productive, profitable, healthy, and sustainable land-use systems.
Intercropping can increase yields or reduce inputs and thus represents (potentially sustainable) agricultural intensification. However, while total yield per acre is often increased dramatically, yields of any single crop often diminish. There are also challenges to farmers relying on farming equipment optimized for monoculture, often resulting in increased labor inputs.
Vertical farming is intensive crop production on a large scale in urban centers, in multi-story, artificially-lit structures, using far less inputs and producing fewer environmental impacts.
An integrated farming system is a progressive, biologically-integrated sustainable agriculture system such as IMTA or Zero waste agriculture, whose implementation requires exacting knowledge of the interactions of multiple species and whose benefits include sustainability and increased profitability. Elements of this integration can include:
- Intentionally introducing flowering plants into agricultural ecosystems to increase pollen-and nectar-resources required by natural enemies of insect pests
- Using crop rotation and cover crops to suppress nematodes in potatoes
See also: Agricultural policy and Agribusiness
The challenges and issues of industrial agriculture for society, for the industrial agriculture sector, for the individual farm, and for animal rights include the costs and benefits of both current practices and proposed changes to those practices. This is a continuation of thousands of years of invention in feeding ever-growing populations.
[W]hen hunter-gatherers with growing populations depleted the stocks of game and wild foods across the Near East, they were forced to introduce agriculture. But agriculture brought much longer hours of work and a less rich diet than hunter-gatherers enjoyed. Further population growth among shifting slash-and-burn farmers led to shorter fallow periods, falling yields and soil erosion. Plowing and fertilizers were introduced to deal with these problems - but once again involved longer hours of work and degradation of soil resources (Boserup, The Conditions of Agricultural Growth, Allen and Unwin, 1965, expanded and updated in Population and Technology, Blackwell, 1980.).
While the point of industrial agriculture is to profitably supply the world at the lowest cost, industrial methods have significant side effects. Further, industrial agriculture is not an indivisible whole, but instead is composed of multiple elements, each of which can be modified in response to market conditions, government regulation, and further innovation, and has its own side-effects. Various interest groups reach different conclusions on the subject.
See also: World population and History of agriculture
|Year||World||Africa||Asia||Europe||Central & South America||North America*||Oceania||Notes|
|8000 BCE||8 000|||
|1000 BCE||50 000|||
|500 BCE||100 000|||
|1 CE||200,000 plus|||
|1750||791 000||106 000||502 000||163 000||16 000||2 000||2 000|
|1800||978 000||107 000||635 000||203 000||24 000||7 000||2 000|
|1850||1 262 000||111 000||809 000||276 000||38 000||26 000||2 000|
|1900||1 650 000||133 000||947 000||408 000||74 000||82 000||6 000|
|1950||2 518 629||221 214||1 398 488||547 403||167 097||171 616||12 812|
|1955||2 755 823||246 746||1 541 947||575 184||190 797||186 884||14 265|
|1960||2 981 659||277 398||1 674 336||601 401||209 303||204 152||15 888|
|1965||3 334 874||313 744||1 899 424||634 026||250 452||219 570||17 657|
|1970||3 692 492||357 283||2 143 118||655 855||284 856||231 937||19 443|
|1975||4 068 109||408 160||2 397 512||675 542||321 906||243 425||21 564|
|1980||4 434 682||469 618||2 632 335||692 431||361 401||256 068||22 828|
|1985||4 830 979||541 814||2 887 552||706 009||401 469||269 456||24 678|
|1990||5 263 593||622 443||3 167 807||721 582||441 525||283 549||26 687|
|1995||5 674 380||707 462||3 430 052||727 405||481 099||299 438||28 924|
|2000||6 070 581||795 671||3 679 737||727 986||520 229||315 915||31 043|
|2005||6 453 628||887 964||3 917 508||724 722||558 281||332 156||32 998**|
An example of industrial agriculture providing cheap and plentiful food is the U.S.'s "most successful program of agricultural development of any country in the world". Between 1930 and 2000, U.S. agricultural productivity (output divided by all inputs) rose by an average of about 2 percent annually, causing food prices to decrease. "The percentage of U.S. disposable income spent on food prepared at home decreased, from 22 percent as late as 1950 to 7 percent by the end of the century."
Main article: Environmental impact of agriculture
Industrial agriculture uses huge amounts of water, energy, and industrial chemicals, increasing pollution in the arable land, usable water, and atmosphere. Herbicides, insecticides, and fertilizers are accumulating in ground and surface waters. "Many of the negative effects of industrial agriculture are remote from fields and farms. Nitrogen compounds from the Midwest, for example, travel down the Mississippi to degrade coastal fisheries in the Gulf of Mexico. But other adverse effects are showing up within agricultural production systems—for example, the rapidly developing resistance among pests is rendering our arsenal of herbicides and insecticides increasingly ineffective."Agrochemicals and monoculture have been implicated in Colony Collapse Disorder, in which the individual members of bee colonies disappear. Agricultural production is highly dependent on bees to pollinate many varieties of fruits and vegetables.
Main article: Rural sociology
A study done for the U.S. Office of Technology Assessment conducted by the UC Davis Macrosocial Accounting Project concluded that industrial agriculture is associated with substantial deterioration of human living conditions in nearby rural communities.
- ^ abEncyclopædia Britannica's definition of Intensive Agriculture
- ^BBC School fact sheet on intensive farming
- ^Factory farming. Webster's Dictionary definition of Factory farming
- ^Encyclopædia Britannica's definition of Factory farm
- ^* Overton, Mark. Agricultural Revolution in England 1500 - 1850 (September 19, 2002), BBC.
- Valenze, Deborah. The First Industrial Woman (New York: Oxford University Press, 1995), p. 183.
- Kagan, Donald. The Western Heritage (London: Prentice Hall, 2004), p. 535-9.
- ^Noel Kingsbury (2009). Hybrid: The History and Science of Plant Breeding. Chicago: University of Chicago Press.
- ^Janick, Jules. "Agricultural Scientific Revolution: Mechanical"(PDF). Purdue University. Retrieved 2013-05-24.
- ^Reid, John F. (Fall 2011). "The Impact of Mechanization on Agriculture". The Bridge on Agriculture and Information Technology. 41 (3).
- ^Stinner, D.H (2007). "The Science of Organic Farming". In William Lockeretz. Organic Farming: An International History. Oxfordshire, UK & Cambridge, Massachusetts: CAB International (CABI). ISBN 978-0-85199-833-6. Retrieved 30 April 2013 ebook ISBN 978-1-84593-289-3
- ^"A Historical Perspective". International Fertilizer Industry Association. Archived from the original on 2012-03-09. Retrieved 2013-05-07.
- ^ abMatson; Parton, WJ; Power, AG; Swift, MJ; et al. (1997). "Agricultural Intensification and Ecosystem Properties". Science. 277 (5325): 504–9. doi:10.1126/science.277.5325.504. PMID 20662149.
- ^ abcdMatthew Scully
Farming has enabled human populations to dominate the world’s landscapes for many thousands of years. The science of agriculture has been refined and perfected over time to accommodate for the ever-increasing human population. Until recent centuries, productive crops were mostly organic and existed with some permanence as part of a landscape. As communities grow though, less and less land is available for food production and existing crops become easily exhausted. Food insecurity caused by rapid population growth has pressured science to step in and produce many synthetic chemicals and gene manipulation techniques to maximize the potential of plants. In addition, agricultural production has increased tremendously worldwide over the last century. Coupled with this growth however is the pollution and degradation of the natural environment. Many agricultural techniques exist today, but in an effort to adjust to the exponential trends of our population without compromising the integrity of the environment it is necessary to have a global transition towards sustainable farming. With the current population at seven billion and rising, an important question must be addressed: What is the most sustainable and cost effective way to feed the world’s population? Fortunately humans have been perfecting agricultural methods for thousands of years, which can help to answer this question.
This paper will analyze and compare two types of farming, organic and conventional. In a comparison of agriculture, my goal is to assess the impact and performance of each practice and then identify the best method for growing crops. Although there are many types of agricultural practices, they can be generalized as sustainable or conventional based on the techniques used. Sustainable / organic farming aims to produce a number of crops, without the use of synthetic chemicals or fertilizers, while enhancing soil composition and promoting biodiversity. This is a traditional, more permanent type of farming that relies on ecosystem services to maintain the integrity of the landscape while still producing sufficient yields. Conventional farming uses synthetic chemicals and fertilizers to maximize the yield of a particular crop or set of crops, which are typically genetically modified. This method requires a significant amount of chemical and energy input and weakens the ecology of a landscape. In a comparative analysis of these two techniques, it is important to highlight the fact that the crops studied differed in soil composition, geography, and rotation systems. “To carry on extensive long-term trials for a number of crops in several different geographical areas would be of fundamental importance to understand the potential of organic farming as well as to improve farming techniques in general.” (Gomiero, Pimentel, and Paoletti 2011). Due to the many different factors determining crop health and productivity, there is a need for much more extensive research on the subject. Therefore, my goal in writing this paper was to use reliable, long-term research that made specific assessments of the two generalized types of farming and then compare the results.
II. History of Agriculture
Agriculture has played a tremendous role in the advancement of human society. Agriculture has been around since roughly 10,000 B.C.E. and has enabled humans to manipulate ecosystems and maximize population growth (Xtimeline.com). The science has encouraged people to live and develop rich, permanent settlements all over the world. When humans first discovered the potential of planting seeds, they suddenly had the ability to explore the world and establish infrastructures wherever soils were fertile.
Soon after the start of agriculture people began to select for genes that maximized plant yields. Selective breeding was first implemented on plants over 10,000 years ago to produce desired characteristics in crops (USDA.gov). This discovery further contributed to the permanence and size of settlements. With breakthroughs in agriculture, populations increased and development spread.
Early farming techniques depended on local climate conditions, but most farmers would continue to plant on the same field year-after-year until the soils were exhausted of nutrients. This encouraged ingenuities such as crop rotation and intercropping (Economywatch.com). Intercropping is a technique in which a variety of crops are grown together, creating a microclimate that favors the survival of each plant, maximizes potential yields and maintains soil fertility (Archaeology.about.com). For example, Native Americans developed an intercropping technique over 5,000 years ago called the three sisters, where maize, beans, and squash were grown together (Archaeology.about.com). Maize consumes a lot of nitrogen, while beans supply nitrogen to the soil, and squash benefits from a shady, moist climate. Intercropping is one of many early discoveries in agriculture still being implemented today that promotes biodiversity, maintains soil composition, and fortifies plant health.
Techniques such as irrigation, intercropping, and crop rotation have progressively increased efficiency in agriculture. Over the last few centuries however, radical changes have been made in farming and many countries have made a shift toward conventional methods. Factors such as growing populations, economic instability, climate change, and pressures from companies to produce higher yields have contributed to this shift. However, adopting these conventional methods subjects farmers to the greed of industry, as their crops depend on a high input of energy, synthetic chemicals, and genetically modified organisms. And once committed to the conventional practices, farmers find themselves locked in a perpetual cycle of loans, subsidies, and debt.
III. Conventional Agriculture
Conventional agriculture is a broad term that has a number of definitions, but a crop can be classified as conventional if synthetic chemicals are used to maintain the plants. A significant amount of chemical and energy input is required in conventional agriculture to produce the highest possible yield of crops. “This method usually alters the natural environment, deteriorates soil quality, and eliminates biodiversity.” (USDA.gov). Conventional agriculture was developed to make farming more efficient, but achieves that efficiency at a major cost to the environment.
The goal of conventional agriculture is to maximize the potential yield of crops. This is achieved through the application of synthetic chemicals, genetically modified organisms, and a number of other industrial products. In maintaining a conventional system, biodiversity, soil fertility, and ecosystems health are compromised (Huntley, Collins, and Swisher). Production of these crops is beneficial to nothing but food security and economy. Once established, a conventional farm requires constant maintenance but produces maximal yields.
Maintenance is made easy for farmers as conventional farming typically involves monocropping, but is also very expensive. In a conventional system farmers will designate entire fields to just one crop, which creates uniformity. Uniformity can determine both the success and failure of conventional systems. A uniform crop is ideal because it reduces labor costs and makes harvesting easy, but it can also impact biodiversity and make crops susceptible to pathogens (Gabriel, Salt, Kunin, and Benton 2013). Chemicals and genetically modified organisms make maintenance of conventional systems relatively simple for farmers, but require a constant input of energy and money. In a conventional system, farmers can apply pesticides and herbicides to crops at a much more efficient rate if they are made up of just one type of plant, but this has a number of unintended consequences. Since the goal of conventional agriculture is to maximize yields, environmental health and biodiversity are usually not preserved.
IV. Sustainable Agriculture
Where conventional farming represents one extreme of agriculture, sustainable farming represents the other. “Organic agriculture is a production system that sustains the health of soils, ecosystems and people. It relies on ecological processes, biodiversity and cycles adapted to local conditions, rather than the use of inputs with adverse effects. Organic agriculture combines tradition, innovation and science to benefit the shared environment and promote fair relationships and a good quality of life for all involved.” (Gomiero, Pimentel, and Paoletti 2011). Sustainable agriculture is a more holistic approach to farming than conventional in that it relies on ecosystem services and is typically much less detrimental to the surrounding landscape. Sustainable agriculture is a natural way to produce food and has a number of social, economic, and environmental benefits.
There are many types of sustainable farming that all rely on natural cycles to ensure plant health and crop performance. Sustainable farming forgoes the use of synthetic pesticides, herbicides, and fertilizers to produce food. Instead, farmers will plant a variety of plants together to promote biodiversity and ward off pests and pathogens (Nicholls and Altieri 2012). Where conventional systems promote uniformity and depend on synthetic chemicals for protection against disease and pests, sustainable systems rely on biodiversity as a measure to protect against these things.
Sustainable agriculture profits farmers, economies, and food banks while existing symbiotically with the landscape. One example of many in sustainable farming practices, which emphasizes economic benefits and environmental health, is conservation agriculture. “By increasing soil organic matter contents and moisture-holding capacity, CA can double subsistence crop yields in areas where use of fertilizers is uneconomic and it can sustain production in years with low rainfall.” (Kassam and Brammer 2013). Conservation agriculture underlines the focus of sustainable agriculture in that it focuses on producing high yields without compromising the integrity of the environment.
V. A Comparison of Agriculture
In a comparison of conventional and sustainable agriculture there should be several points of focus: production, biodiversity, soil composition / erosion, water use, energy use, and greenhouse gas emissions. The environmental impact and production levels of each method will determine its overall viability as a solution to growing trends. It is necessary to make these comparisons in order to identify the best agricultural method that can sustainably meet the needs of the current population. Although these comparisons are based off of scientific data, there is much more research that needs to be done in order to make a definitive judgment.
To meet the needs of the current population requires a tremendous amount of resources. Not taking into account the environmental damage associated with intense production, conventional agriculture is a feasible way to provide for more people; “… population growth and increasing consumption of calorie- and meat-intensive diets are expected to roughly double human food demand by 2050.” (Mueller, Gerber, Johnston, Ray, Ramankutty, and Foley 2012). In addressing this rapid growth, production levels become a serious point of comparison. “Organic yields are globally on average 25% lower than conventional yields according to a recent meta-analysis, although this varies with crop types and species and depends on the comparability of farming systems.” (Gabriel, Salt, Kunin, and Benton 2013). Most research indicates that sustainable crops produce much less than conventional systems.
There are many environmental benefits associated with sustainable agriculture, but its production capacity is limited. In general, sustainable agriculture fails to match up to conventional agriculture in terms of production. This result varies though, and in some instances organic crops actually best conventional crops. For example, under drought conditions organic crops tend to produce higher yields because they typically retain more water; “As part of the Rodale Institute Farming System Trial (from 1981 to 2002), Pimentel et al., (2005) found that during 1999, a year of extreme drought, (with total rainfall between April and August of 224 mm, compared with an average of 500 mm) the organic animal system had significantly higher corn yield (1,511 kg per ha) than either organic legume (412 kg per ha) or the conventional (1,100 kg per ha).” (Gomiero, Pimentel, and Paoletti 2011). Although certain conditions may favor organic crops, conventional agriculture is designed to produce the highest yields possible.
Many factors contribute to this difference in production. Conventional crops are designed specifically to produce maximal yields; therefore, the difference should be expected. Typically conventional crops are genetically modified to perform better under certain conditions than sustainable crops (Carpenter 2011). However, these crops are also sprayed with toxic pesticides and herbicides to make up for their uniformity. Some research has been done to determine whether increased biodiversity is related to increased yields; “…farmland biodiversity is typically negatively related to crop yield; generally, organic farming per se does not have an effect other than via reducing yields and therefore increasing biodiversity.” (Gabriel, Salt, Kunin, and Benton 2013). Although levels of production are reduced in sustainable agriculture, studies show that higher levels of biodiversity are linked to healthier crops.
Biodiversity plays a large part in this comparison because it is a determinant of agricultural health and performance. The greater the biodiversity, the more immune plants are to pests and disease (Gomiero, Pimentel, and Paoletti 2011). This is important to highlight because conventional agriculture discourages biodiversity and instead relies on synthetic chemicals to maintain crop health. Over 940 million pounds of pesticides are being applied annually with only 10% of that reaching the desired target, a number that could be greatly reduced if conventional agriculture were to implement sustainable alternatives (Sustainablelafayette.org). Techniques such as integrated pest management and intercropping could be applied to conventional systems and in turn promote biodiversity.
High biodiversity is important to sustainable farming because it enhances the performance of the ecological cycles that the crops depend upon. Organic agricultural systems are typically much more rich in nutrients and diverse in organisms than conventional systems; “…organic farming is usually associated with a significantly higher level of biological activity, represented by bacteria, fungi, springtails, mites and earthworms, due to its versatile crop rotations, reduced applications of nutrients, and the ban on pesticides.” (Gomiero, Pimentel, and Paoletti 2011). It is important to encourage high nutrient levels and biodiversity as these two factors contribute significantly to the health of the crops and the landscape. Although biodiversity does not directly determine crop yield, it does play a major role in the health and permanence of sustainable farms.
Despite the impacts conventional methods have on agricultural land, not all conventional farms degrade biodiversity. In fact, there are many ways farmers can reduce the amount of chemicals and energy they use by implementing low input alternatives; “Overall, the review finds that currently commercialized GM crops have reduced the impacts of agriculture on biodiversity, through enhanced adoption of conservation tillage practices, reduction of insecticide use and use of more environmentally benign herbicides and increasing yields to alleviate pressure to convert additional land into agricultural use.” (Carpenter 2011). The global impact agriculture has can be significantly reduced if conventional farmers adopt sustainable techniques.
In addition to higher levels of biodiversity, sustainable farming is typically associated with better soil quality. Organic farms have stronger soil ecology because they promote biodiversity rather than uniformity; “The results confirm that higher levels of total and organic C, total N and soluble organic C are observed in all of the organic soil.” (Wang, Li, and Fan 2012). The increased concentrations of these nutrients can be contributed to the depth of the food web and amount of biomass in sustainable systems. “In a seven-year experiment in Italy, Marinari et al. (2006) compared two adjacent farms, one organic and one conventional, and found that the fields under organic management showed significantly better soil nutritional and microbiological conditions; with an increased level of total nitrogen, nitrate and available phosphorus, and an increased microbial biomass content, and enzymatic activities.” (Gomiero, Pimentel, and Paoletti 2011). Sustainable crops are more permanent than conventional crops because they work in harmony with the landscape rather than drain it of nutrients and biomass.
Soil management is vital for existing farms because agricultural production is increasing globally and land is becoming less available to accommodate this growth. Conventional systems can improve soil quality by practicing sustainable methods like no-tillage farming, agroforestry, and integrated pest management, but sustainable agriculture is the most effective form of food production in terms of maintaining soil conditions. “Establishing trees on agricultural land can help to mitigate many of the negative impacts of agriculture, for example by regulating soil, water and air quality, supporting biodiversity, reducing inputs by natural regulation of pests and more efficient nutrient cycling, and by modifying local and global climates.” (Smith, Pearce, and Wolfe 2012). Again, research shows that an increase in biodiversity and a reduction of chemical input can result in conventional farms with more healthy soils and improved crop performance.
A major problem concerning agriculture is soil erosion caused by nutrient loss, run-off, salinity, and drought. Soil erosion presents a threat to the growth of agriculture because, “Intensive farming exacerbates these phenomena, which are threatening the future sustainability of crop production on a global scale, especially under extreme climatic events such as droughts.” (Gomiero, Pimentel, and Paoletti 2011). Organic systems enhance soil composition as well as prevent soil erosion due to the greater amount of plant material and biomass in the soil. Conventional systems manipulate the landscape rather than adapt to it; “…soils under organic management showed <75% soil loss compared to the maximum tolerance value in the region (the maximum rate of soil erosion that can occur without compromising long-term crop productivity or environmental quality −11.2 t ha−1 yr−1), while in conventional soil a rate of soil loss three times the maximum tolerance value was recorded.” (Gomiero, Pimentel, and Paoletti 2011). Compared to sustainable farming, conventional crops are terribly inefficient at maintaining the integrity of agricultural landscapes. Conventional agriculture is therefore unable meet the demands of the growing populations without consuming a substantial amount of land and non-renewable resources.
On a global scale, water is a renewable resource that can meet the needs of our current population. Locally, however, water is a scarce resource and must be appropriated efficiently. The amount of fresh water available for consumption globally is small, but regional constraints make accessing that water even more difficult for many millions of people. Agriculture accounts for approximately 70% of water use worldwide (USDA.gov). Increasing demand for fresh water is pressuring global stocks. To conserve this resource a drastic overhaul of water saving techniques, especially in agriculture, must occur.
Due to the abundance of flora and fauna in sustainable systems, organic soil typically retains much more water than conventional soil. This increased retention rate enables sustainable agricultural systems to produce much higher yields than conventional systems during drought conditions (Gomiero, Pimentel, and Paoletti 2011). This is a desirable characteristic in agricultural land as it allows crops to be more tolerable to changing climate. “In heavy loess soils in a temperate climate in Switzerland water holding capacity was reported being 20 to 40% higher in organically managed soils than in conventional ones… The primary reason for higher yield in organic crops is thought to be due to the higher water-holding capacity of the soils under organic management.” (Gomiero, Pimentel, and Paoletti 2011). To manage available water resources, sustainable agriculture is the more efficient approach to feeding the world.
A gap exists between current production rates and potential production rates of crops. Through better management of water and soil, much greater yields can be produced. Increasing efficiency to 100% is not entirely feasible, but implementing sustainable farming techniques would conserve resources and improve crop performance; “Globally, we find that closing yield gaps to 100% of attainable yields could increase worldwide crop production by 45% to 70% for most major crops (with 64%, 71% and 47% increases for maize, wheat and rice, respectively).” (Mueller, Gerber, Johnston, Ray, Ramankutty, and Foley 2012). Meeting future food demands is a dynamic problem that requires consideration of all things, but most importantly water and soil conservation.
Sustainable agriculture relies solely on natural processes for input and recycles nutrients on-site to eliminate the use of non-renewable resources. Alternatively, conventional agriculture requires an incredible amount of energy to produce, prepare, and transport food. Energy efficiency is important to agriculture as it can reduce greenhouse gas emissions and lower costs of production; “Agricultural activities (not including forest conversion) account for approximately 5% of anthropogenic emissions of CO2 and the 10–12% of total global anthropogenic emissions of GHGs (5.1 to 6.1 Gt CO2 eq. yr−1 in 2005), accounting for nearly all the anthropogenic methane and one to two thirds of all anthropogenic nitrous oxide emissions are due to agricultural activities.” (Gomiero, Pimentel, and Paoletti 2011). Agriculture is responsible for a significant percentage of greenhouse gas emissions, but can also mitigate this impact using sustainable methods. Better management of agricultural land is required to reduce the effects of crop production.
Sustainable agriculture has the ability to offset global greenhouse emissions at a greater rate than conventional agriculture because it is more permanent and does not require much input to produce food. Conventional systems are inefficient at capturing carbon because of soil composition, constant production, and how much energy is being used to maintain the crops. “We use so much machinery, pesticides, irrigation, processing, and transportation that for every calorie that comes to the table, 10 calories or energy have been expended.” (Sustainablelafayette.org). However, there are measures that can be taken to increase energy efficiency. “This carbon can be stored in soil by SOM and by aboveground biomass through processes such as adopting rotations with cover crops and green manures to increase SOM, agroforestry, and conservation-tillage systems.” (Gomiero, Pimentel, and Paoletti 2011). Conventional agriculture operates at a net energy loss, but implementing sustainable practices can reduce costs and benefit the surrounding landscape.
Sustainable agriculture aims to enhance the composition of a landscape while producing sufficient yields. This method is so efficient compared to conventional agriculture because it requires no input of synthetic chemicals or fertilizers, which accounts for a large amount of the greenhouse gas emissions. However, energy efficiency also takes into account the ratio of input to output. In that sense, there is no substantial difference between the two types of agriculture; “…the energy efficiency, calculated as the yield divided by the energy use (MJ ha−1), was generally higher in the organic system than in the conventional system, but the yields were also lower. This meant that conventional crop production had the highest net energy production, whereas organic crop production had the highest energy efficiency.” (Gomiero, Pimentel, and Paoletti 2011). Even though conventional systems produce greater yields than sustainable systems, organic crop production is the most energy efficient method.
Studies point toward sustainable agriculture as the best solution to managing the growing population. Although the benefits of sustainable agriculture are abundant, there are several constraints to adopting this method worldwide. Climate conditions vary with geography so where sustainable agriculture is the most efficient system in one part of the world, it may not be entirely feasible in another. “Some authors suggest the adoption of integrated farming, rather than upholding solely organic practices, which they find more harmful than conventional farming, for instance in the case of pest control technologies.” (Gomiero, Pimentel, and Paoletti 2011). Many factors determine the performance of agricultural methods and often the most effective type of agriculture requires a combination of techniques. In addition to local constraints, sustainable agriculture also requires much more labor to maintain crops.
The science of agriculture has allowed human populations to grow exponentially and dominate the world’s landscapes. Advancements in this science have enabled humans to manipulate entire ecosystems to cater to their survival. But as populations continue to grow, resources are becoming limited. Water, fuel, and soil are three important factors determining the survival the world’s population and it is crucial that they are used as efficiently as possible. In a comparison of sustainable and conventional agriculture, organic farming methods are shown to perform much better for a number of indicators. Sustainable agriculture consumes less water and energy, enhances soil composition, and forgoes synthetic chemical input. Conventional agriculture cannot meet the needs of the current population without compromising the integrity of the environment. Sustainable agriculture has the potential to sequester carbon, feed the world, and enrich the environment. The social, economic, and environmental benefits of this system are reasons why sustainable agriculture is the most viable way to accommodate growing trends.
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