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The Green revolution is a process of technological development of agricultural techniques that began in Mexico in 1944 and has since spread throughout the world. The goal of the Green revolution was to increase the efficiency
of agricultural processes so that the productivity of the crops was increased and could help developing countries to face their
growing populations needs.
The Green revolution has since started to face strong criticisms (discussed below), and is being replaced in some cases by
integrated farming or organic farming techniques.
History
The Green Revolution began in 1944 when the Rockefeller Foundation founded an institute to improve the agricultural output of Mexican
farms. This produced astounding results, so that Mexico went from having to import half its wheat to self-sufficiency by 1956, and by 1964, to exports of half a million tons of
wheat.
From there, the technologies were exported abroad, finding use in regions all over the world. The success in increasing yields
was undisputable. The growth of crop yields was such that agriculture was now able to outstrip population growth — per
capita production increased every year following 1950.
The use of genetic engineering in agriculture to create
genetically modified foods is viewed by
some as the natural continuation of the Green revolution.
Technologies
The Green revolution technologies broadly fall into two major categories. The first is the breeding of new plant varieties;
the second is the development of new agricultural
techniques.
Hybrid strains
Most crops consumed by the public-at-large in industrialized nations are Green revolution crops. The design of hybrid strains (so called because they
were created by cross-breeding a broad range of varieties to produce the desired combination of characteristics in a single
variety, although random
mutagenesis was also used) was motivated by a desire to, first, increase crop yield, and also to increase durability for
transport and longevity for storage. Norin 10 wheat is an example of
such a strain that helped developing countries, such as India and Pakistan to increase the productivity of their crops. Since then, strains have been bred
for better appearance (e.g. plumper tomatoes, straighter, more evenly-colored rows of
corn).
Since improved crop yield was produced mostly through the use of heavy fossil
fuel inputs (discussed below), the increased efficiency of Green revolution strains is geared towards these inputs; that is,
the strains are more efficient at exploiting the chemical
fertilizers used, and also are designed to be easier to harvest mechanically.
Agricultural Techniques
The techniques refined and developed by the Green revolution are, roughly:
- Extensive use of chemical fertilizers - Every plant basically relies on several basic compounds in order to grow. Primary is
nitrogen need. Only in the nitrate form
can plants absorb the nitrogen they require. Certain microorganisms found
in the soil are able to convert atmospheric nitrogen into the nitrate form plants can use. Also, some biological nitrogen fixation can take place by microorganisms living in
small nodules on the roots of certain plants, such as legumes. Phosphates are also important, as well as numerous trace elements. Soil pH (acidity or alkalinity) must also be adjusted to the
optimal conditions for the crop in question. Previously proper soil conditions had relied only on techniques such as crop
rotation, mixing of crops, or organic fertilizers like horse manure. The major development of the Green revolution in this field was the use of chemical
fertilizers to adjust the soil pH balance and achieve the right levels of all the important chemical compounds needed for the
plant to grow.
- Irrigation - Although it has been in use in agriculture for thousands of
years, the Green revolution further developed irrigation methods to allow for more efficient irrigation.
- Use of heavy machinery - Mechanized harvesters and other machinery was not new to agriculture - the McCormick reaper was developed in
the nineteenth century - but the Green revolution allowed a
drastic reduction in the input of human labor to agriculture by extending the use of machinery to automate every possible
agricultural process.
- Pesticides and herbicides -
The development of chemical pesticides and herbicides (including organochlorine and organophosphate compounds) allowed further improvements in crop yields by allowing for
efficient weed control (by use of herbicide early in the growing season) and eradication of insect pests.
In recent years, genetic engineering techniques have been used to further enhance some of these Green revolution advances,
especially the use of pesticides and herbicides. For example, many commercial crops these days have engineered herbicide
tolerances, so that application of more herbicide will eliminate undesirables (weeds) while leaving the crop unaffected.
Criticisms of the Green revolution
The Green revolution has been criticized on several grounds, but the primary argument is environmental. The Green revolution,
critics argue, is flawed on several counts:
- Loss of biodiversity and food quality - The spread of Green revolution
hybrids and the associated techniques has resulted in many fewer varieties of crops being grown. Some crops have seen upwards of
a 90% reduction in crop varieties. Dependence on one or a few forms of a crop means increased fragility of the population and
impaired ability to improve crops in the future, in addition to the unmeasurable loss of the contribution of a varied diet. In
addition Green revolution crops are bred for growth efficiency and longevity (and sometimes appearance), not for health value. As
such many hybrid crops are inferior in nutritional value to their ancestors. The introduction of Green revolution staples into
regions that previously had hundreds or even thousands of varieties of crops, as well as the replacement of various nutrition
sources with a single Green revolution alternative have led to poor nutrition as a result of switching from varied diets with
many nutrition sources to single-crop or fewer-crop diets.
- Fossil fuel dependence - While agricultural output increased as a result of the Green revolution, the energy input into the
process (that is, the energy that must be expended to produce a crop) has also increased at a greater rate, so that the ratio of
crops produced to energy input has decreased over time. Green revolution techniques also heavily rely on chemical fertilizers,
pesticides and herbicides, some of which must be developed from fossil fuels, making agriculture increasingly reliant on
petroleum products.
- Pollution - Fertilizer, pesticide and herbicide runoff continue to be a
significant source of pollution, and a major source of water pollution. Although the dangerous, toxic and sometimes
cancer-causing pesticides of the early half of the century (like 2,4,5-T
and DDT) have mostly been phased out of agricultural usage (although DDT continues to be used
in Third-world nations), their effects have often not been erased.
- Land degradation -
Critics charge that the Green revolution destroys soil quality over the long range. This is a result of a variety of factors,
including increased soil salinity
that results from heavy irrigation; "burning" of the soil by heavy use of chemical fertilizers, killing off beneficial soil
microbes and other organisms; erosion of the soil; and loss of valuable
trace elements. This can lead to increased reliance on chemical inputs to compensate for deteriorating soil quality, a process
which may ultimately fail.
Finally, there is an important social dimension which must be considered. The Green revolution introduced major changes into a
world where the majority of the people still depend on farming for their livelihood. The result of many of these techniques was
the encouragement of large-scale industrial agriculture at the expense of small farmers, who were unable to compete with the
high-efficiency Green revolution crops. The result has been massive displacement and increasing urbanization and poverty amongst
these farmers, and the loss of their land to large agricultural companies, who are much more able to manage the considerable
enterprise involved in effectively exploiting Green revolution techniques. This may be not unlike the Luddites complaints about the Industrial
Revolution. Prominent critics of the Green Revolution include Indian writer and activist Vandana Shiva.
The Green Revolution in agriculture helped food production to keep pace with population growth. Many people believe a second
Green Revolution is likely to take place, and should focus on the food crops grown by the 2 billions of people lacking food
security.
See also
External links
[1] http://www.orst.edu/instruction/bi301/greenrev.htm
[2] http://www.agron.iastate.edu/courses/agron342/revolution.html
[3] Shiva, Vandana. "Stolen Harvest: The Hijacking of the Global Food Supply", South End Press 2000
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