5. What can be inferred from paragraphs 4 and 5 about soil conservation efforts in the United States?

  • A. Encouraging minimum tillage practices resulted in much more efficient soil conservation than converting erodible land into vegetative cover.
  • B. Complete retirement of land combined with soil-conservation practices significantly reduced soil erosion.
  • C. Measuring the success of government-supported conservation programs over extended periods of time was sometimes as difficult as getting the programs started.
  • D. The reduction of energy use due to practices such as conservation tillage and land retirement was much larger in the United States than in any other country.

Paragraph 5

Another example of an effort to control soil erosion is the Conservation Reserve Program (CRP). Created in the United States in 1985, the CRP aimed to convert 45 million acres of highly erodible land into permanent vegetative cover under ten-year contracts. Under this program, farmers were paid to plant grass or trees on fragile cropland. The retirement of 35 million acres under the CRP, together with the adoption of conservation practices on 37 percent of all cropland, reduced soil erosion in the United States from 3.1 billion tons in 1982 to 1.9 billion tons in 1997.


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