A Cornell University scientist says soil around the world is being swept and washed away 10 to 40 times faster than it's being replenished.
Professor of Ecology Davide Pimentel says cropland the size of Indiana is lost each year, yet the Earth's need for food and other grown products continues to soar.
"Soil erosion is second only to population growth as the biggest environmental problem the world faces," said Pimentel. "Yet, the problem, which is growing ever more critical, is being ignored because who gets excited about dirt?"
Pimentel said 99.7 percent of human food comes from cropland, which is shrinking by nearly 37,000 square miles each year due to soil erosion, while more than 3.7 billion people are malnourished.
The study, which pulls together statistics on soil erosion from more than 125 sources, notes the United States is losing soil 10 times faster -- and China and India are losing soil 30 to 40 times faster -- than the natural replenishment rate.
Damage from soil erosion worldwide is estimated to be $400 billion per year.
Pimentel's study appears in a recent issue of the Journal of the Environment, Development and Sustainability.
Copyright 2006 by United Press International
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