Geography
The Mississippi River is the second longest river in the United States, stretching more than 2,302 miles from its source in the northwestern part of Minnesota and flowing through 10 states before emptying into the Gulf of Mexico. Its drainage basin covers all or part of 31 states and two Canadian provinces, comprising nearly 40 percent of the area of the United States and more than 10 percent of the continent north of Mexico. While significance of the river’s role in the development of the United States is hard to overstate and its influence on the culture of many of its watershed cities and towns is significant, the power and capability of the river to shape the land is particularly impressive.
The sheer power of the Mississippi River comes from the combination of its volume and speed. As the river flows from its source to the Gulf of Mexico, it picks up sediment from the surrounding areas that it passes through, thus increasing its volume. The Mississippi River also has tremendous velocity, with average flow rates ranging from 500,000 cubic feet per second during peak times to as low as 400,000 cubic feet per second during non-peak times.
Tectonic and Weather Events
Tectonic and weather events can also play a role in controlling the path of the Mississippi River. Earthquakes can cause uplift, subsidence, and other geologic events that can reshape the path of the river. Additionally, hurricanes and other severe weather events can cause flooding, which can cause the Mississippi River to change course. As the Mississippi River has changed course throughout its history, numerous meanders, oxbow lakes, and other features have been created.
Dynamic Processes
The path of the Mississippi River is constantly changing due to dynamic processes such as erosion and deposition. As the river’s flow brings sediment from upstream, it can create new deposits, leading to the formation of new oxbow lakes or meanders. Over time, these features can become well established, altering the course of the river.
Erosion can also cause the Mississippi River to change its course. The powerful waters of the river can carve away at the banks and cut new channels, resulting in a new course. In some cases, this process can cause the river to abandon its original path, creating what are known as abandoned river channels.
Human Impacts
Humans also play a role in controlling the path of the Mississippi River. Humans have constructed various dams and locks along the river, altering its flow. In some cases, these structures can reroute the river’s flow, causing it to change course. Additionally, humans have created large levee systems along the Mississippi in order to contain the river and prevent its water from flooding nearby communities. While this has had significant benefits for the areas that have been protected from flooding, it has also had impacts on the course of the river, forcing it to take a more direct and straight path.
Flood Management
In order to protect people and property from the destructive power of the Mississippi River, a variety of flood management techniques have been employed. The most common of these techniques is the creation of levees, which are structures designed to contain the river and protect areas from flooding. In some cases, these levees can alter the course of the river and can result in it taking a more straight and direct path. Additionally, the U.S. Army Corps of Engineers has implemented a variety of other flood management techniques, such as dredging, through which they can clear sediment from the bottom of the river and increase the flow rate. The Corps has also constructed numerous dams and locks throughout the course of the river.
Ecological Impacts
While the various forms of flood management have had significant benefits in terms of protecting lives and property, they have also had a variety of unintended consequences, particularly with regards to the environment. The construction of dams, levees, and other flood management techniques can cause a decrease in the water quality of the river, as well as disrupt natural processes such as fish migration and the life cycles of other aquatic species. Additionally, the structure of the river is heavily altered by these flood management techniques, leading to a decrease in the biodiversity of the river. As a result, it is important to consider both the benefits and the potential consequences of flood management techniques when making decisions about how to most effectively manage the Mississippi River.
Riparian Ecosystems
Riparian ecosystems, or the areas of land directly adjacent to a river or stream, can be significantly impacted by the course of the Mississippi River. These ecosystems are highly sensitive to alterations in the river’s flow, and when the river changes its course, the riparian ecosystems can be altered as well. In some cases, these changes can have wide ranging impacts on the ecology of an area, such as the effect of a new course on the local fish population. Additionally, the changes can have implications for the recreational potential of an area, as the alteration in the river’s course can open up new areas for exploration, while also closing off access to areas that were previously navigable.
Conclusion
In conclusion, the course of the Mississippi River is significantly impacted by a variety of factors, both natural and human-made. Tectonic and weather events can alter the course of the river as can natural processes such as erosion. Additionally, humans have constructed a number of dams, levees, and other structures that can also alter the course of the river and the flow of its water. Finally, changes to the course of the river can have a variety of impacts on the riparian ecosystems along its banks, which can have implications for the ecology of an area as well as its potential for recreation.
Human Interventions
Human interventions have had an increasingly significant influence on the course of the Mississippi River. In order to protect populated areas from flooding, humans have constructed numerous dams, levees, locks, and other structures along its banks. These structures can reroute the flow of the river or speed up its flow rate, thus altering its course. A wide variety of techniques have also been developed to help manage the flow of the river, such as dredging and the use of floodgates. Additionally, in recent years, humans have increasingly utilized the power of the river to generate electricity, albeit to the detriment of the river’s ecosystem.
Environmental Impacts
The various human interventions that have altered the flow and course of the Mississippi River have had a number of negative environmental impacts. Perhaps the most sigificant of these impacts has been the decrease in water quality as a result of alterations to the flow of the river. Additionally, the alteration in the river’s course can disrupt natural processes, such as the life cycles of aquatic species, and can lead to a decrease in the biodiversity of the river and its riparian ecosystems. Finally, the construction of dams and other structures can have long lasting implications for the areas around them, leading to increased erosion, decreased sediment transport, and other alterations in the local ecologies.
Mitigation Efforts
In order to minimize the negative impacts of the alteration of the Mississippi River’s course, a variety of mitigation efforts have been implemented. In some cases, the U.S. Army Corps of Engineers, which is responsible for implementing many of the flood management techniques, has attempted to minimize the impacts of the structures they build by constructing fish ladders and other structures that can allow aquatic species to pass through. Additionally, environmental organizations have worked to restore and reestablish riparian ecosystems along the river, aiming to bring back the natural balance that was disrupted by the alterations in the river’s course.
Economic Factors
The alteration of the Mississippi River’s course due to human interventions has also had a number of economic impacts. The various levees, dams, and other flood management structures often require significant investment from state and federal governments, as well as from private entities. Additionally, the disruption of the riparian ecosystem can lead to decreased recreational potential of an area, thus leading to a loss of tourism or other economic activities that rely on the ability of people to recreate and enjoy the natural environment.
Long-term Impacts
The long-term impacts of the alteration of the course of the Mississippi River are largely unknown, though a few trends have emerged in recent years that suggest that significant changes may be in store for the area. In particular, many have argued that the rate at which the river is shifting course has been increasing in recent years as a result of climate change. Additionally, it is possible that the alteration in the flow of the river could lead to increased erosion in some areas, while also leading to decreased sediment transport in other areas. It is therefore important to take a comprehensive view of the potential impacts of the alteration of the river’s course in order to ensure the health of the ecosystem and the people who depend on it.
