The Green Revolution
Food production is increased either by cultivating more land or by producing bigger yields. Since 1950, increases in yield have come from what is commonly called the green revolution. The green revolution involves planting monocultures of hybrid plant varieties and by applying large amounts of inorganic fertilizer, irrigation water, and pesticides. Between 1950-1970 this approach resulted in dramatic increases in crop yields mainly in more developed countries. After 1967, a variant of this 1st green revolution was transmitted to many LDCs. This 2nd green revolution involved new high yield, fast-growing dwarf varieties of rice and wheat, specially bred for tropical and subtropical climates. However, achieving high yields with these new crops still required large inputs of fertilizer, water and pesticides.
Increasing agricultural productivity through green revolution technologies relies heavily on the use of fossil fuels for running machinery and producing fertilizers. Today, it now takes about 1.2 barrels of oil to produce a single ton of grain in more developed countries. This is some 7 times greater than from 1950. Thus, industrial agriculture has become addicted to oil, using about 8 % of world oil output.
Future increases in production are predicted to come from genetic engineering and other forms of biotechnology. In the next 20 to 40 years scientists hope to breed high yield plant strains that have greater resistance to insects and disease, thrive on less fertilizer, make their own nitrogen fertilizer like legumes, do well in slightly salty soils, and make more efficient use of solar energy during photosynthesis. A good example of the results of this type of research, is triticale, a new cereal grain produced by cross breeding wheat and rye. Triticale can flourish under a variety of conditions including poor soils, and cold and hot climates. Some analysts, however, point to several factors that have limited the spread and long-term success of the green revolutions:
The Blue Revolution
Many nations have in the last few decades turned to the oceans to supply some of their food resources. Using various harvesting techniques, about 40 different species of marine organisms are caught for human and livestock consumption. Of these forty species, Cod, Herring, Jack, Mackerel, and Tuna account for over 60 % of the commercial fish harvested. From 1950 to 1990, the world catch of fish has increased by about 400 %. Because of this drastic increase, the numbers of some species of fish have declined substantially due to overfishing. In Canada, overfishing of North Atlantic Cod has caused the government to take extreme actions to stop the destruction of this fishery.
Another technique humans use to supplement their food resource from the sea is fish farming or aquaculture. Fish farming involves cultivating aquatic species in a controlled environment. Usually the controlled environment is a floating cage, a pond or lake, or a fenced-in area of lake or ocean. In 1990, aquaculture supplied the world with 15 % of its seafood. Of this 15 %, three-fourths of it comes from LDCs.
Fish farming does create some ecological problems. For example, the development of shrimp farming in Southeast Asia is responsible for the clearing of millions of hectares of mangrove swamps. Mangrove swamps are the home to several thousand different species of plants, birds, reptiles, amphibians, fish, insects, and mammals.
March 11, 1997
Copyright © 1996/97 Michael Pidwirny