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.
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 a continuation of the Green revolution.
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.
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.
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.
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 & 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 inputed 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 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.
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.
[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