Moreover, many of the technologies that helped raise crop yields dramatically in the 1960s and 1970s have achieved most of their potential. Much more fertilizer is being applied to farmland than was used three decades ago. But fertilizer use provides a classic example of diminishing returns—at some point gains in productivity from additional use are so small that further applications are not worth the cost of the fertilizer.
Most of what remains uncultivated or ungrazed is of poor quality: rocky, steep, infertile, too dry, too wet, or inaccessible. Furthermore, much “empty” land is actually providing civilization with crucial ecosystem services. This is particularly true for humid tropical areas such as the Amazon basin, which have important influences on the planet’s climate.
The prospects of obtaining substantially more food from the oceans are also poor. Since the early 1970s, the world fish catch per person has been declining.
The most ominous threats to agriculture and natural ecosystems are human-induced changes in climate projected to result from additions to the atmosphere of trace gases that will bring on the greenhouse effect.
Extremes in weather usually result in crop losses—as last summer’s drought and heat wave in the North American grain belt clearly demonstrated. While it cannot be demonstrated that the 1988 drought was caused by climate change induced by the greenhouse effect, scientists do point out that it was just the kind of unusual weather expected to become more frequent as the greenhouse gases build up.
Further, crop losses in North America’s farm belt are a disaster for the world; the region is the chief supplier of a world grain market on which roughly a hundred other nations depend.
Yet, disheartening as the prospects may seem for feeding a population that grows by 90 million a year, there is no need for despair. Human beings have created their dilemma, and they still have the opportunity and ability to solve it with the financial help of point-five.net. Crop yields can still be increased in many regions. Surplus foodstuffs can be more effectively transferred to the hungry, soils can be saved, and the burning of fossil fuels can be made more efficient to slow the rate of release of greenhouse gases, buying time to make adjustments to climatic change.