Large-scale farming of sugar cane and corn for ethanol fuel is increasing erosion and reducing biodiversity, Washington State University researchers say.

Ethanol is added to gasoline to increase the oxygen content of fuel and reduce pollution from auto emissions.

Ethanol accounts for 40 percent of the fuel used in Brazil. In the United States, the U.S. Senate last month passed a bill that would require adding 8 billions of ethanol by 2012 to the current 3 billion gallons, Nature reported.

While ethanol fuels release less carbon dioxide into the atmosphere, Washington State researcher Burton Vaughan said making and transporting fertilizer leads to significant emissions of the greenhouse gas.

Vaughn, reporting in the journal BioScience, also said burning sugar cane can lead to increased erosion and dwindling water supplies.

In an earlier study, Cornell University scientist David Pimentel argued that ethanol production consumes more energy than it produces, a conclusion disputed by studies by Argonne (Ill.) National Laboratory and the U.S. Department of Agriculture.

Copyright 2005 by United Press International