Mississippi River Ecosystem
Mississippi River is the fourth longest river in the world and a major part of the United States’ geologic, climatological, hydrologic and ecological systems. It originates in Minnesota and flows south to the Gulf of Mexico. The river is vitally important to the region, serving as a major resource for transportation, recreation and sediment transport, yet very few people are aware of its tidal nature.
It may come as a surprise to many, but the Mississippi River is actually part of a tidal ecosystem. While there are no large ocean tides, currents, like those found in estuaries and bays, exist. During the months of April, May, and June, the river experiences its highest frequencies of tidal activity. These tidal activity affects the water levels, the movement of sediment and biological activity of the aquatic life in and around the river.
Tidal Reversals
The Mississippi River experiences two main types of tidal oscillations: diurnal and semidiurnal. Diurnal oscillations, which last for 24 hours, are caused by the rise and fall of the ocean tides. Semidiurnal oscillations, which have a period of 12 hours and 17 minutes, are caused by the combined effect of the diurnal ocean tides and the spring-neap cycle. During the spring-neap cycle, the moon and sun are in a certain alignments, resulting in stronger or weaker tidal activity.
Every two weeks, the Mississippi River experiences a tidal reversal, in which the direction of the current reverses. This reverses the flow of the river, pushing water upstream from the Gulf of Mexico. During these reversals, the sediments, nutrients and other aquatic life within the river are pushed and pulled along with the changing currents.
Aquatic Life
Tidal reversals affect the aquatic life within the Mississippi River. Aquatic species such as catfish and bluegill, for example, take advantage of the seasonal nutrients brought in by the flow of the tidal current. Other species, such as mussels and crustaceans, make use of the sediment patterns that result from tidal changes. Additionally, the speed of the currents changes with the tide, dictating migratory timing and behavior of species such as dolphins, manatees, and sturgeons.
Habitat Variability
The shifting nature of the Mississippi River’s tidal activity also has an effect on the river’s habitats. At certain times of the year, the river’s current will be slow, allowing riverside vegetation and wetlands to grow and develop. Conversely, during other times of the year, the fast-moving currents of the tidal reversals will erode and demolish these habitats.
Impact of Human Activities
Over the years, human activities, such as dredging and levee construction, have caused severe disruption to the Mississippi River’s tidal patterns. Dredging has greatly reduced the speed of the river’s currents, causing sediment to accumulate in some areas and erode away in others. The levees along the banks of the river prevent the regular floods that were once a part of the natural cycle, drastically altering the habitats and species that thrive there.
Conservation Efforts
In recent years, conservation efforts have been made to help restore the balance and health of the Mississippi River’s tidal ecosystem. Organizations such as the United States Army Corps of Engineers, The Nature Conservancy and The Wetland Resources Development Program and have been working to restore the river’s habitats and cycles.
Economic Benefits
The restoration of the Mississippi River’s tidal ecosystem brings with it a variety of economic benefits. The restoration of wetlands and coastal areas create a wide range of habitats for fish and wildlife, providing food and shelter to a wide variety of species, many of which are valuable sources of food or are of great recreational fishing value. In addition, the revival of marshlands can help to reduce flooding which costs billions of dollars in damage and repairs every year.
A Balanced Ecosystem
The Mississippi River is an integral part of the United States’ geologic, climatological, hydrologic and ecological systems and a key part of maintaining a healthy environment. It is essential to recognize and manage the river’s tidal ecosystem in order to maintain a balanced and healthy environment, both locally and in the Gulf.
Climate Change Implications
Climate change threatens the Mississippi River’s coastal environment. Rising temperatures and sea levels endanger the habitats of important species and could even displace them. The tidal oscillations and natural resources provided by the Mississippi River support hundreds of species, many of which are facing increasing threats from human activities and climate change.
Scientific Research
In an effort to better understand and protect the Mississippi’s tidal ecosystem, scientists have conducted extensive research in the area. Through their studies, they are gaining a greater understanding of the river’s unique geology, hydrology, aquatic life and ecology. This research has revealed the intricate connections between the many aspects of the river’s environment, allowing scientists to make better informed decisions when it comes to conserving the region.
Conclusion
The Mississippi River is an essential part of the United States’ geologic, climatological, hydrologic and ecological systems and its tidal ecosystem helps to sustain a range of species. It is essential that we recognize the importance of the river’s tidal cycles and take steps to conserve and protect it. By doing so, we can ensure that the river continues to be a rich source of food and shelter for a variety of species and a major resource for recreational activities and transportation.
