Excerpt
MANY conventional agricultural practices clearly lack long-term sustainability. Prior to 1985, the degradation of the nation's soil, water, fish, and wildlife went on practically unabated in many areas. In 1982, 173 million acres (41 percent of all available cropland) were eroding at a rate of three billion tons per year—a level far in excess of sustainable soil loss tolerance levels (25). In Iowa, for example, two bushels of soil were being shed for each bushel of corn grown (9). In other parts of the country, loss of land productivity associated with soil erosion over the past 100 years was projected to be as high as 60 percent (25).
The use of nitrogen, phosphorus, and potassium fertilizer on U.S. cropland more than tripled from 1960 to 1981—from 7.3 million tons to 23.6 million tons. The total amount of active pesticide ingredients applied on U.S. farms increased 170 percent from 1964 to 1982, to a high of 500 million pounds (20). Because most agricultural chemicals are made from fossil fuels, more than three calories of energy are being expended to grow one calorie of food (9). The cost of these expensive chemical inputs …
Footnotes
Laurence R. Jahn is chairman of the board for the Wildlife Management Institute, 1101 14th Street, Suite 725, Washington, D.C. 20005. Eric W. Schenck, now a supervisor, Environmental Services Section, Kansas Department of Wildlife and Parks, Box 54A, Route 2, Pratt, 67124, was director of conservation for the Wildlife Management Institute.
- Copyright 1991 by the Soil and Water Conservation Society
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