SIOUX FALLS - A new study documents a loss of 1.3 million acres of grassland over a five-year period in South Dakota, North Dakota, Nebraska, Minnesota and Iowa.

The research by Christopher Wright and Michael Wimberly of the Geographic Information Science Center of Excellence at South Dakota State University says a doubling in commodity prices has created incentives for landowners to convert grassland to corn and soybean cropping.

The authors say the conversion rates have not been seen in the Corn Belt since the 1920s and 1930s, the era of rapid mechanization of U.S. agriculture.

Grassland conversion between 2006 and 2011 was mostly concentrated in North Dakota and South Dakota, east of the Missouri River.

The study appears in the Proceedings of the National Academy of Sciences of the United States of America.

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