BROOKINGS, S.D. (AP) - An expert on soil science at South Dakota State University says wetlands in eastern North Dakota and South Dakota are shrinking at a rapid pace.

Professor Carol Johnston compared Department of Agriculture crop maps with wetland maps from the U.S. Fish and Wildlife Service and the U.S. Geological Survey to determine the wetland loss of the Prairie Pothole Region in the eastern Dakotas.

Her study was published in Wetlands, the Journal of the Society of Wetland Scientists.

Johnston says nearly 13,000 acres of wetlands have been lost each year over the past 30 years.

She says the rate the wetlands are shrinking each year keeps going up.

She says the changes in wetlands affect not only wildlife but human beings.

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