A Brief History of the Mississippi River's Physical Template

Wednesday, September 11, 2013: 11:40 AM
Marriott Ballroom B (The Marriott Little Rock)
Jonathan Remo , Department of Geography and Environmental Resources, Southern Illinois University, Carbondale, Carbondale, IL
The majority of the Mississippi River drainage basin and its associated topography have developed during the recent geologic past (< 65 million years). During this period, the Mississippi Basin has developed into one of the largest drainage basins (~3,224,000 km2) on Earth. The basin accumulates an average estimated annual water volume of ~530 x 109 m3, making the Mississippi the seventh largest river in the world volume. The basin’s major vegetation biomes (forests in the eastern and mountainous regions; prairies in western regions) were established ~10,000 years before present.  Substantial alteration of the basin’s native vegetation began in the early-19th century with clearing of the land for agriculture. Today, nearly all the prairie, and a significant portion its forests have been converted to well-drained agricultural land.  River regulation occurred concurrently with the development of industrialized agriculture.  River regulation provided several major ecosystem services (human benefits).  These include navigation for commodity transport, flood control (both urban and agricultural), water supply, and hydroelectric power.  However, these benefits have come with changes and challenges.  Examples of these changes and challenges include homogenization of water flows, considerable reductions in sediment transport, and simplification of channel forms.  Additionally, conversion of the basin’s land to facilitate industrialized agriculture has resulted in significant changes in the basin’s hydrology, the degradation of water quality in many its waterways, and subsequent loss of native biodiversity and productivity. While the benefits of industrialized agriculture and river regulation continue for some, we are faced with the challenge of maintaining these benefits while also addressing the major challenges that arise from such large scale provisioning of ecosystem services.