Characterization of the Suspended-Sediment Regime and Bed-Material Gradation of the Mississippi River Basin. Potamology Program (P-I). Report 1, Volume II

摘要

The Lower Mississippi River Basin is not a significant source area for material that can be eventually transported as suspened sediment; however, because of the strategic location of the basin between a large portion of the interior of the North American Continent and the Gulf of Mexico, it must pass large volumes of water and sediment through its major waterways. Even in its natural state, the Mississippi River was a heavy sediment-bearing stream, and if left to the natural order of events, would probably be building a new main-stem delta in what is now the atchafalaya Subbasin. The greatest single suspended-sediment contributor to the Lower Mississippi River is the Upper Mississippi, which in turn derives much of its load from the Missouri River. Although many tributaries upstream from the Upper Mississippi-Missouri confluence contribute measurable loads to the main stem, the Missouri River input dominates the character of the suspened-sediment regime of the Upper Mississippi between St. Louis and Cairo.