Organic and sustainable farming

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"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..." -International Federation of Organic Agriculture Movements[1]

Organic farming is a form of agriculture in which agricultural land is cultivated without the use of artificial fertilisers, or artificial pesticides, growth regulators and livestock feed additives. Genetically modified organisms and engineered nanoparticles are forbidden as well. The use of agricultural machines (running on either biofuels or fossil fuels) is allowed.[2][3] The goals of organic farm systems include the maintenance of soil fertility, efficient usage of water, maximizing soil fertility, and improved animal welfare as well as environmental aspects indirectly related to farming such as reduction of energy use and avoidance of pollution (Trewavas 2001).

Sustainable agriculture is the practice of farming using principles of ecologyW. Unlike organic agriculture, sustainable agriculture focuses on the ability of providing food on the long-term. As such, besides artificial fertilisers and pesticides[4]it also does not allow the use of agricultural machines running on non-renewable resourcesW. Besides this, it focuses on finding the most energy-efficient and cost-effective method of using agricultural machines and non-renewable natural resources (ie phosphate, ...). For this reason it also implements natural biological cycles and controls where possible.[5]

Except for some particularities, both methods of farming are hence quite similar, employing ecologic methods as polyculture, decreased (or zero-) tillage, crop rotation, nutrient cyclingW (ie composting, ...), no or reduced chemical fertilizer applications, no or reduced reduced chemical pesticide application, biological pest control and/or fostered biodiversity, mechanical cultivation, and other techniques (ie mulching, ...)[6]

Contents

[edit] History

In 1924 Rudolf Steiner, at Koberwitz, presented a course on agriculture in which he characterised a farm as 'an organism'.[7]

The term "organic farming" was coined in 1940 by Lord Northbourne and first appeared in his book 'Look to the Land'[8] and was influenced by Steiner's characterisation of the farm as an organism and the practices of biodynamic farming.[9]

The International Federation of Organic Agriculture Movements was founded in 1972 in Paris.[10]

The term "sustainable agriculture" was coined in 1950's by Gordon McClymont. Sustainable agriculture took off in the United States after passing the 1990 farm bill.[11] More recently, as consumer and retail demand for sustainable products has risen, organizations such as Food Alliance and Protected HarvestW have started to provide measurement standards and certification programs for what constitutes a sustainably grown crop.[12]

[edit] Organic farming

Some recent studies have suggested that organic farming can potentially produce more than conventional farming methods on the same area of land.[13] Note that besides conventional organic farming, another variant also exist called biodynamic agriculture.

One of the most important issues in organic farming is the eliminating of pests at a ecological way. Full details on this can be found at Integrated Pest Management.

Another important issue with organic farming is the use of organic fertilizers.

[edit] Conserving natural resources

The physical aspects of sustainability are partly understood.[14] Practices that can cause long-term damage to soil include excessive tillageW (leading to erosion) and irrigation without adequate drainage (leading to salinizationW). Long-term experimentsW have provided some of the best data on how various practices affect soil properties essential to sustainability. There is a federal agency, USDA-Natural Resources Conservation Service that specializes in providing technical and financial assistance for those interested in pursuing natural resource conservation and production agriculture as compatible goals.

The most important factors affecting plant growth at an individual site are sun, air, soil and water. Of these, water and soil qualityW and soil quantity are most amenable to human intervention through time and labour.

Although airW and sunlightW are available everywhere on EarthW, crops also depend on soil nutrients and the availability of waterW. When farmers grow and harvestW crops, they remove some of these nutrients from the soil. Without replenishment, land suffers from nutrient depletion and becomes either unusable or suffers from reduced yieldsW.

Sustainable agriculture depends on replenishing the soil while eliminating (or atleast minimizing) the use of non-renewable resources, such as natural gas (used in converting atmospheric nitrogen into synthetic fertilizer), or mineral ores (e.g., phosphate). Sustainable options for replacing nutrient inputs as phosphorus, potassium, etc. are limited. Nitrogen is, in principle, available indefinitely from sources as:

Community and farm composting of kitchen, yard, and farm organic waste can provide most if not all the required needs of local farms. This composting could potentially be a reliable source of energy. Many scientists, farmers, and businesses have debated how to make agriculture sustainable. Using community recycling from yard and kitchen waste utilizes a local area's commonly available resources. These resources in the past were thrown away into large waste disposal sites, are now used to produce low cost organic compost for organic farming.

Besides the self-produced organic waste, soil amendmentW can be used. Soil amendments is locally recycled compost from community recycling centers. By using this local recycling system small farmers can produce products from waste from the cities and sell the products back to the people in the city via the local farmers' markets, in effect closing the loop.

Additional options to recycling nutrients are the growing of seasonal crops, the use of long-term crop rotationW and the use of sturdy native plants and livestock landracesW.

The growing of seasonal crops allows to reduce energy requirements (ie no need of greenhouses, heating, reduced organic pesticide use, ...) Native crops are better adapted to a lack of nutrients and other less than ideal conditions such as pests, drought, excessively watered fields, ... For the crops, it is best to choose not only native crops, but also perennial versions of the crops, where possible (ie with grain crops, ...)[17]

In addition to reducing the energy requirements by selecting more suitable crops, the use of more suitable farm equipment is also important. For example, the current method of agriculture requires 10 calories of fossil energy for 1 calorie of food[18][19] More suitable farm equipment can include draft animals[20] or traction engines to replace the fuel-inefficient tractors which are now being used.

[edit] Water

In some areas, sufficient rainfall is available for crop growth, but many other areas require irrigation. For irrigation systems to be sustainable they require proper management (to avoid salinization) and must not use more water from their source than is naturally replenished, otherwise the water source becomes, in effect, a non-renewable resource. Improvements in water well drilling technology and submersible pumpsW combined with the development of drip irrigation and low pressure pivots have made it possible to regularly achieve high crop yields where reliance on rainfall alone previously made this level of success unpredictable. However, this progress has come at a price, in that in many areas where this has occurred, such as the Ogallala AquiferW, the water is being used at a greater rate than its rate of recharge.

Several steps should be taken to develop drought-resistant farming systems even in "normal" years, including both policy and management actions:

  1. improving water conservation and storage measures
  2. providing incentives for selection of drought-tolerant crop species
  3. using reduced-volume irrigation systems
  4. managing crops to reduce water loss or
  5. not planting at all.[21]

Indicators for sustainable water resource development are:

  • Internal renewable water resources. This is the average annual flow of rivers and groundwater generated from endogenous precipitation, after ensuring that there is no double counting. It represents the maximum amount of water resource produced within the boundaries of a country. This value, which is expressed as an average on a yearly basis, is invariant in time (except in the case of proved climate change). The indicator can be expressed in three different units: in absolute terms (km3/yr), in mm/yr (it is a measure of the humidity of the country), and as a function of population (m3/person per yr).
  • Global renewable water resources. This is the sum of internal renewable water resources and incoming flow originating outside the country. Unlike internal resources, this value can vary with time if upstream development reduces water availability at the border. Treaties ensuring a specific flow to be reserved from upstream to downstream countries may be taken into account in the computation of global water resources in both countries.
  • Dependency ratio. This is the proportion of the global renewable water resources originating outside the country, expressed in percentage. It is an expression of the level to which the water resources of a country depend on neighbouring countries.
  • Water withdrawal. In view of the limitations described above, only gross water withdrawal can be computed systematically on a country basis as a measure of water use. Absolute or per-person value of yearly water withdrawal gives a measure of the importance of water in the country's economy. When expressed in percentage of water resources, it shows the degree of pressure on water resources. A rough estimate shows that if water withdrawal exceeds a quarter of global renewable water resources of a country, water can be considered a limiting factor to development and, reciprocally, the pressure on water resources can have a direct impact on all sectors, from agriculture to environment and fisheries.[22]

[edit] Soil

Walls built to avoid water run-off

Soil erosion is fast becoming one of the worlds greatest problems. It is estimated that "more than a thousand million tonnes of southern Africa's soil are eroded every year. Experts predict that crop yields will be halved within thirty to fifty years if erosion continues at present rates."[23] Soil erosion is not unique to Africa but is occurring worldwide. The phenomenon is being called Peak Soil as present large scale factory farming techniques are jeopardizing humanity's ability to grow food in the present and in the future.[24] Without efforts to improve soil management practices, the availability of arable soilW will become increasingly problematic.[25]

Folowing soil management techniques can be used to reduce soil erosion

[edit] Other methods for farming more effectively

Polyculture practices in Andhra Pradesh

Besides having many plant nutrients in the soil, another factor for plant growth is having a good soil texture. Without a good soil texture, the plant can not effectively extract the nutrients from the soil. Other techniques that improve the soil quality are the use of biochar and compost tea.

Besides improving the soil, we can also apply effective cultivation methods. 4 useful cultivation practices in sustainable agriculture are polyculture combined with crop rotationW, the use of fallow periods, companion planting/intercropping and seasonal crop growing.

The growing of a mixture of crops (polyculture) reduces disease or pest problems in comparison with monoculture.[26] Polyculture has rarely, if ever, been compared to the more widespread practice of growing different crops in successive years (called crop rotationW) with the same overall crop diversityW. Cropping systems that include a variety of crops (polyculture and/or rotation) may also replenish nitrogen (if legumes are included) and may also use resources such as sunlight, water, or nutrients more efficiently[27].

Crop rotation is the growing of a crop on a different section of the land each year. It can be done with or without fallow periods. Fallow periods are periods in the year in which land is prepared (plowed and tilled) but left unused (so no crops are grown) for one growing season. With crop rotation it does means that a section of the land is left unused each year (this section of land rotates each year). This allows the land to recover. During the fallow period, we can also introduce some nutrients back into the land by growing Nitrogen fixationW plants on it. Fallowing can however also cause problems, particularly where a field is left exposed to the elements. The sun and rain in combination can dry the soil and wash away the nurients. An alternative to fallow periods is to plant nitrogenous rich legumes in a soil as part of Crop rotation

Intercropping is where two or more varieties of plant that do not compete with each other for light, water, ... are grown close to each other. Often, this means using plants of different heights, ... Intercropping allows a greater density of plants, which can each take up different nutrients from a well kept soil. Sometimes intercropping occurs when different varieties are planted in alternating rows. But true intercropping can also, be a lot more chaotic with fields resembling weed beds, due to the growth of multiple varieties of crop. Intercropping a pungent crop or a brightly coloured one can repel pests, trap crops function as "bait" attracting a pest away from the vegetable that is being grown. Companion planting also places plants that grow well together near each other, but uses plants of a same height and which may also stimulate each other in growing even stronger/faster. Agroforestry is a type of agriculture that makes extensive use of intercropping.

Seasonal crop growing involves the growing of a diverse number of perennial crops in a single field. The crops are grown one after another, each of which growing in separate season so as not to compete with each other for natural resources.[28] This system would result in increased resistance to diseases and decreased effects of erosion and loss of nutrients in soil.

[edit] Overview of combined organic/sustainable farming techniques

The following table lists the techniques in order of importance.

Method Notes
Monoculture or Polyculture Choosing polyculture increases crop resistance against pests/diseases. It can however be more difficult to work with (ie for harvesting, ...).
Crop rotationW with/without fallowing Crop rotation controls the build up of pest and diseases. Soil remains higher quality and pests of a particular vegetable or plant will not be allowed more than one year to breed and thrive Fallowing gives an area of poor soil, or a diseased area of soil time to recover by leaving it empty. It is often used as part of a crop rotation. This can result in reduction of a pest and/or improvements of the soil
Using strong crop species, healthy seeds, false sowing beds, professionally executed cultivation Using strong crop species increases resistance to disease, and improves crop growth. Healthy/good quality seeds need to be used to decrease infection of plants. If no good quality seeds are available or if they are too expensive, cleaning the seeds can reduce the pests that are present. False sowing beds are weeded/prepared seed beds which are left for a short while (some 14 days), allowing any weed seeds to germinate. These can then be easily removed (as there are not yet any crops germinating) and after this the crops can be sown. Professionally executed cultivation refers to ie using a correct sowing depth, seed/plant spacing, irrigation (in dry periods), climate in the greenhouse, weed control, favorable sowing and planting times, ...
Intercropping and companion planting Intercropping allows to "layer" the crops so that they compete less for sun, water and nutrients. It thus makes the plants grow stronger and makes them more resistant to pests. Companion planting places similar crops together which also actually benefit from each other.
Removing infected cropsW alltogether and/or only the infected leaves, using closed seasons, paring and using clean tools/machinery Infected crops crops act as a host and heavily increase the occurence and/or spreading of a pest or disease. Closed seasons mean that crops are left to grow for a specific season and are not left in the field outside that time. In non closed seasons, particularly when crops are left all years, pests have (more) time to use plants as hosts (ie to breed). Paring is the cutting of of diseased parts, and/or dirty or unused roots before transplanting the crop. This can remove pests and diseases. Unclean tools can cause the spreading of diseases and pests. Farmers should ensure that they clean their tools when moving between areas of the field.
Use of fertilizers Use of fertilizers can promote the growth of plants, making them less likely to be attacked by pests particularly when they are young. Fertilisers come in organic and chemical form. Chemical fertilizers can be expensive, and their chemical makeup can reduce the quality of soil and the cause the build up of chemicals/salinization. Humus/green manure, animal manure are alternatives. The fertilization needs to be oriented to the specific requirements of the plant (non-concentrated nitrogen fertilisation), taking also into account the type of fertiliser we use.
Mulching and using cover crops Mulching can be used in a number of ways to reduce pests. By mulching a soil it naturally represses weeds and the soil does not dry, allowing healthy growth of plants. Cover crops have a same weed-controlling function. Plants which overhang close to the ground can be easily attacked by ground dwelling animals such as caterpillars, or decompose through contract with the soil. Mulching with (ie with tomatoes) reduces the risk of blight and moulds (which come through contact with damp ground)
Tillage Tillage refers to the breaking up/loosening of the soil, ie to improve soil structure, as well as for "primary weeding" (mechanical control). It needs to be done at the right time. Loosening of the soil needs to be done in any situation where the soil has become consolidaded (ie after rain, after winter in temperate countries, ...) Deep tillage (ie through ploughing, ...) can cause eutrophication, loss of nutrients.
Weeding Weeding generally involves far shallower agitation of the soil (and thus brings less soil disturbance) than with tillage. It is generally done by hand rather than with mechanized equipment and is done regularly. It is differentiated from the "primary weeding". Primary weeding is done to clear huge amounts of plants, weeds ie with new agricultural fields or just after winter when the soil needs to be loosened anyway. (which is done with mechanized equipment). Weeding results in young plants not having to fight so much for soil nutrients, water and space. They grow more quickly, and hence are less likely to be attacked by pests when they are young and weaker. Pests can also be attracted to a vegetable patch which is rich in weeds.
Use of pesticides Pesticides are sprayed to kill or repel particular pests and/or diseases. It generally involves the use of organic pesticides, and only in extreme cases the use of chemical pesticides. This as repeated spraying of the latter liquid can reduce the quality and build up of chemicals in the soil

[edit] Particularities of organic farming

Organic farms need to comply to following requirements in order to allow wearing the title of being organic:

  • The land must be free of prohibited substances for 3 years prior to organic farming
  • Seeds should be organic but right now the use of some non-organic seeds is permitted
  • The use of genetic engineering, sewage sludge, or ionizing radiation is prohibited
  • Weeds are controlled with management practices and lots of work
  • Garden pests are handled with integrated pest management practices which include biological, physical, and mechanical controls.
  • Some organic pesticides are permitted
  • To maintain soil fertility organic farmers use methods such as: crop rotations, cover crops, animal manures, compost, and diversity in crops.
  • Some organic fertilizers are permitted

[edit] Economics

Labor costs of organic farming are higher, but costs of inputs are often lower, as there are no chemical fertilizers, pesticides or herbicides to be purchased. This is an advantage in development contexts - see Permaculture and development.

Socioeconomic aspects of sustainable farming are but partly understood. Regarding less concentrated farming, the best known analysis is Netting's study on smallholder systems through history.[29] The Oxford Sustainable GroupW defines sustainability in this context in a much broader form, considering effect on all stakeholders in a 360 degree approach

Given the finite supply of natural resourcesW at any specific cost and location, agriculture that is inefficient or damaging to needed resources may eventually exhaust the available resources or the ability to afford and acquire them. It may also generate negative externalityW, such as pollution as well as financial and production costs.

The way that crops are soldW must be accounted for in the sustainability equationW. Food sold locally does not require additional energy for transportation (including consumers). Food sold at a remote location, whether at a farmers' market or the supermarketW, incurs a different set of energy cost for materials, labourW, and transport.

[edit] Location of the farm

There has been considerable debate about where farms are best located. Some argue that farms are best located in/near cities to shorten the distance the food needs to travel. Others have argued that privately produced food is even more efficient. However, the latter may not always generate sufficient food.

[edit] Off-farm impacts

A farm that is able to "produce perpetually", yet has negative effects on environmental quality elsewhere is not sustainable agriculture. An example of a case in which a global view may be warranted is over-application of synthetic fertilizer or animal manuresW, which can improve productivity of a farm but can pollute nearby rivers and coastal waters (eutrophication). The other extreme can also be undesirable, as the problem of low crop yields due to exhaustion of nutrients in the soil has been related to rainforestW destruction, as in the case of Slash-and-burn agricultureW for livestock feed.

Sustainability affects overall production, which must increase to meet the increasing food and fiber requirements as the world's human population expands to a projected 9.3 billion people by 2050W. Increased production may come from creating new farmland, which may ameliorate carbon dioxide emissions if done through reclamation of desert as in PalestineW, or may worsen emissions if done through slash and burnW farming, as in BrazilW. Additionally, Genetically modified organismW crops show promise for radically increasing crop yields, although many people and governments are apprehensive of this new farming method.

Some advocates favour sustainable agriculture as the only system which can be sustained over the long-term. However, organic production methods, especially in transition, yield less than their conventional counterparts and raise the same problems of sustaining populations globally.

[edit] Sources and references

  1. Definition of Organic Agriculture
  2. Paull, J., 2010, Nanotechnology: No Free Lunch!, Platter 1(1):8-17
  3. Directorate General for Agriculture and Rural Development of the European Commission What is organic farming ?
  4. Not allowed as these too are unsustainable in the long term
  5. What is Sustainable Agriculture?. United States Department of Agriculture, Alternative Farming Systems Information Center.
  6. Warde, Jon, ed. The Backyard Builder: Over 150 Projects for Your Garden, Home and Yard. New York: Random House, 1994.
  7. Paull, John (2011) "Attending the First Organic Agriculture Course: Rudolf Steiner’s Agriculture Course at Koberwitz, 1924", European Journal of Social Sciences, 21(1):64-70.
  8. Paull, John, 2006 The Farm as Organism: The Foundational Idea of Organic Agriculture Journal of Bio-Dynamics Tasmania, (80) 14-18.
  9. Paull, John (2011) "The Betteshanger Summer School: Missing link between biodynamic agriculture and organic farming", Journal of Organic Systems, 2011, 6(2):13-26.
  10. Paull, John (2010) From France to the World: The International Federation of Organic Agriculture Movements (IFOAM), Journal of Social Research & Policy, 1(2): 93-102.
  11. Food, Agriculture, Conservation, and Trade Act of 1990 (FACTA), Public Law 101-624, Title XVI, Subtitle A, Section 1603
  12. Organic and non-GMO Report. New certification programs aim to encourage sustainable farming.
  13. E.g. Organic farming can feed the world, University of Michigan study shows, July 10, 2007
  14. Altieri, Miguel A. (1995) Agroecology: The science of sustainable agriculture. Westview Press, Boulder, CO.
  15. [1]
  16. Proceedings of the National Academy of Sciences of the United States of America, March 25, 2008 vol. 105 no. 12 4928-4932 [2]
  17. http://www.sciencedaily.com/releases/2009/08/090804071358.htm Perennial grain crops advocated by The Land Institute]
  18. http://earth-ways.co.uk/why-is-the-future-permaculture/
  19. http://www.permaculture.co.uk/articles/why-church-needs-return-its-pastoral-roots-permaculture-visions-rural-minster
  20. Fernando Funes Monzote using draft horses instead of tractors to heavily increase farm efficiency
  21. [3]
  22. [4]
  23. Musokotwane Environment Resource Centre for Southern Africa CEP Factsheet. http://www.sardc.net/imercsa/Programs/CEP/Pubs/CEPFS/CEPFS01.htm
  24. Peak Soil: Why cellulosic ethanol, biofuels are unsustainable and a threat to America http://culturechange.org/cms/index.php?option=com_content&task=view&id=107&Itemid=1
  25. CopperWiki Soil erosion http://www.copperwiki.org/index.php?title=Soil_erosion
  26. Nature 406, 718-722 Genetic diversity and disease control in rice, Environ. Entomol. 12:625)
  27. Field Crops Res. 34:239
  28. Glover et al. 2007. Scientific American
  29. Netting, Robert McC. (1993) Smallholders, Householders: Farm Families and the Ecology of Intensive, Sustainable Agriculture. Stanford Univ. Press, Palo Alto.

[edit] See also

[edit] Further reading

  • Laki, G. (2002): Added value as the basis of sustainable agriculture’s subsidy system. In: (Eds. Trebicky, V. - Novak, J.) "Rio+10 Transition from Centrally Planned Economy to Sustainable Society? (Visegrad Agenda 21)", Institute for Environmental Policy, Prague, 2002, 49. p.
  • Laki, G., Szakál, F. (2002): Added Value as a key indicator for sustainable agriculture. In: A mezőgazdasági termelés és erőforrás-hasznosítás ökonómiája - VIII. Nemzetközi Agrárökonómiai Tudományos Napok, SZIE Gazdálkodási és Mezőgazdasági Főiskolai Kar, Gyöngyös, 6 p.
  • Madden, Patrick (March/April 1986). "Debt-Free Farming is Possible". Farm Economics (Pennsylvania: Cooperative Extension Service, U.S. Dept. of Agriculture [and] The Pennsylvania State University). ISSN 0555-9456
  • Pender J., Place F., Ehui S. (2006) Strategies for Sustainable Land Management in the East African Highlands
  • Pollan M. (2007) The Omnivore's Dilemma: A Natural History of Four Meals by
  • Roberts W. (2008) The No-Nonsense Guide to World Food by Roberts W. (2008)

[edit] External links

Wikipedia
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