| Earth Report: The Essential Guide to Global... |
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Erosion is a big problem even in the United States, the "world's breadbasket." Around 1980, the United States was estimated to be losing nearly 4 billion tons of soil a year, enough to fill a freight train 600,000 miles long -- twenty-four times the circumference of Earth. About a third of America's cropland is affected, and drops in yield attributable to erosion have already been noted, including a 2 percent decline in grain production per acre in Illinois -- in the richest part of the grain belt -- between 1979 and 1984. |
agriculture farming land soil |