As a result, the surface of the river is above that of the surrounding plain in some places. Sediment has also been deposited on the riverbed. Natural levees, built up from sediment carried and deposited in times of flood, border the river for much of its length. As with all graded streams, the Mississippi River walks a fine line between temporarily picking up sediment load and then depositing it again. It is a classic example of a stream in equilibrium, in which stream erosion and deposition have combined to produce a gradient that allows the stream to carry a sediment load that is in balance with the load that is delivered to the stream by its tributaries. The lower Mississippi River meanders in great loops across a broad alluvial plain (also known as the Mississippi River Delta). It enters Arkansas at Fort Smith (Sebastian County) and passes through Little Rock (Pulaski County), Pine Bluff (Jefferson County), and other cities before terminating at its confluence with the Mississippi River east of Dumas (Desha County). This relatively large river flows east-southeast across the entire state. The Arkansas River, at 1,469 miles in length, is one of the most significant tributaries of the entire Mississippi River drainage network and is particularly important to Arkansas. ![]() The watersheds of the Arkansas, Red, and White rivers are among the most important tributaries of the lower basin. The Lower Mississippi Valley extends from the confluence of the Ohio and Mississippi rivers at Cairo to the mouth of the Mississippi River in the Gulf of Mexico. The Missouri River is the largest tributary in the upper basin and furnishes approximately fifteen percent of the total discharge and constitutes more than forty percent of the Mississippi system drainage area. The Upper Mississippi Basin, for example, extends from its point of origin at Lake Itasca to the confluence of the Ohio and Mississippi rivers at Cairo, Illinois. This large watershed has been divided into several smaller basins for convenience of study. These channels served as the flow-path for the Mississippi River and its tributaries. This was the case with the Mississippi River Valley more than 8,000 years ago when glacial meltwater carved channels through the glacial debris. Of all the processes functioning to alter the surface of the earth, none is more important than the work of streams. Stuttgart (Arkansas County), for example, located near the confluence of the Arkansas, White, and Mississippi rivers, is known as the “Duck and Rice Capital of the World.” Eastern Arkansas is also part of the Mississippi Flyway and provides important waterfowl habitat for a large number of birds, including a wide variety of ducks. Arkansas is the leading rice producer in the United States and ranks high in the production of cotton and soybeans. The alluvial plain in Arkansas has some of the richest and most productive agricultural land in the nation. The Delta Cultural Center in Helena explores the Mississippi’s natural and historical legacies and its influence on regional culture, especially blues music. The river’s impact on human history is evidenced in historic river ports such as Osceola (Mississippi County) and Helena (Phillips County). The alluvial plain has remnant wetlands and several large oxbow lakes including Lake Chicot, Arkansas’s largest natural lake. This vast and vital habitat supports a wide variety of flora, fauna, and aquatic species. The river created what is often referred to as the “ Delta” of eastern Arkansas, which is part of the nation’s largest alluvial plain. It flows along almost the entire eastern border of Arkansas. The Mississippi River is a dominant physical feature of many states in the middle United States, including Arkansas. This vast river system, which includes several large tributaries, drains 1,260,000 square miles, making it the largest drainage basin in terms of area in North America and the third largest in the world. ![]() ![]() Covering forty-one percent of the forty-eight contiguous United States, its watershed stretches across the heart of the nation. It is truly one of the nation’s most important assets. ![]() This great river, often referred to as the “Mighty Mississippi,” originates as a small brook flowing out of Lake Itasca in Minnesota and, 2,340 miles later, empties into the Gulf of Mexico. The Mississippi River is the largest and most important river in North America.
0 Comments
Leave a Reply. |