Habitat changes in the Upper Mississippi River floodplain Wlosinski, J. H., D. A. Olsen, C. Lowenberg, T. W. Owens, J. Rogala, and M. Laustrup. 1995. Habitat changes in the Upper Mississippi River floodplain. Pages 234-236 in E. LaRoe, G. S. Farris, C. E. Puckett, P. D. Doran, and M. J. Mac, editors. Our living resources: A report to the Nation on the distribution, abundance, and health of U.S. plants, animals, and ecosystems. U.S. Department of the Interior, National Biological Service, Washington, D.C. Reprinted by U.S. Geological Survey, Environmental Management Technical Center, Onalaska, Wisconsin, June 1997. LTRMP 97-R008. 3 pp. (NTIS #PB97-179758) ABSTRACT The floodplain of the Upper Mississippi River has been significantly modified by man since 1824. Changes include the removal snags and sandbars, elimination of rapids, closing of side channels, construction of wing dams, 29 navigation locks and dams, and hundreds of miles of levees. Watershed changes have transformed much of the landscape from forest/grassland habitats to agriculture. We studied floodplain changes by analyzing historical water elevation and discharge data collected since 1861 and spatial data since 1891. Open water and marsh habitats have generally increased in the dammed portion of the river. A 28% reduction in open water and a 38% reduction in woody and terrestrial habitats have occurred In areas unaffected by dams. Water levels as a function of discharge have changed significantly at both low at high flow levels. KEYWORDS Floodplain, geographic information systems, habitat, Upper Mississippi River