The Western Corn Belt Plains is a Level III ecoregion designated by the Environmental Protection Agency (EPA) in seven U.S. states, though predominantly in Iowa.
[1][2] Once covered with tallgrass prairie, over 75 percent of the Western Corn Belt Plains is now used for cropland agriculture and much of the remainder is in forage for livestock.
Major environmental concerns in the region include surface and groundwater contamination from fertilizer and pesticide applications as well as impacts from concentrated livestock production.
One of the youngest and flattest regions in Iowa, the Des Moines Lobe ecoregion is a distinctive area of Wisconsinan glacial stage landforms currently under extensive agriculture.
In the northern portion of the region, the glacial deposits are thin, and shallow limestone bedrock creates karst features such as sinkholes and sags.
There are no natural lakes of glacial origin in this region, but overflow areas and backwater ponds occur on some of the larger river channels contributing to some diversity of aquatic habitat and a large number of fish species.
Surrounded by bluffs capped with deep loess, the historic island-studded meandering river channel has been stabilized and narrowed to manage discharge and to promote navigation and agriculture.
Geography ranges from fairly flat floodplains and outwash plains in the uplands, to some ridges, ravines, and bluffs, especially near the rivers and streams that drain the area.
Dissected hills with deep, silty, well drained soils supported a potential natural vegetation of tallgrass prairie with scattered oak-hickory forests along stream valleys.
The Western Loess Hills ecoregion extends south from Iowa and covers only a small area in northwestern Missouri.
The deep loess-dominated hills have greater relief and a higher drainage density than the Steeply Rolling Loess Prairies (47e) to the east.
The more irregular topography and erosive, silty soils contribute to a mixed land use with less cropland and more pasture and woodland than neighboring regions.