Breath of Clarity

Comment #3: Riparian Ecosystems and Wetland Values

Original Post by Kayla Sizemore:

1. Compare and contrast the hydrology, function, and geomorphology of riparian ecosystems with forested swamps (like cypress) and freshwater marshes. Discuss the hydrology …geomorphology ..and function of each one of the wetlands separately first. Then discuss their similarities and differences.

Riparian ecosystems have a hydrology heavily influenced by river flood pulses, which typically occur during the wet winter/spring, with dry conditions for much of the growing season (Mitsch and Gosselink 2015, 381). These ecosystems can be mesic, occurring on river floodplains, or arid, occurring along high order rivers. Riparian ecosystems can vary in vegetation, which is determined by the cross-sectional morphology, including braiding of the stream, width of the floodplain, soil type, and elevation and moisture gradients (Mitsch and Gosselink 2015, 379). Riparian zones may contain both forested swamps and freshwater marshes, so hydrology and geomorphology can vary significantly.

Forested swamps within riparian ecosystems, such as alluvial cypress swamps, are dominated by spring floods and late-summer flow minima (Mitsch and Gosselink 2015, 381). These swamps are continuously or almost continuously flooded, and can have varying geomorphology including dome swamps, dwarf cypress swamps, lake-edge swamps, slow-flowing stands, and alluvial river swamps (Mitsch and Gosselink 2015, 379). Vegetation in forested swamps is dependent on seasonal flooding, which allows for seed dispersal and growth, while the dry season allows for regeneration. Water quality in alluvial river swamps is often different from the adjacent river as these swamps are typically fed by not only flooding rivers, but also groundwater discharge (Mitsch and Gosselink 383).

Freshwater marshes within riparian ecosystems have a hydrology that is predominantly influenced by the adjacent river system. overflowing lakes and rivers supply water and nutrients to adjacent riparian marshes (Mitsch and Gosselink 2015, 343). This creates a slight unpredictability for the hydroperiod, as river/stream discharge, lake water levels, and precipitation vary due to weather shifts from year to year (Mitsch and Gosselink 2015, 343). These marshes can vary gretaly in nutrient content, and have vegetation consistent with other freshwater marshes, such as reed grass, cattail, and wild rice.

Although swamps and freshwater marshes within riparian systems differ in some ways, there are also similarities between the two. One major similarity is their dependence on the adjacent river system. Hydrology for both swamps and marshes in riparian ecosystems is dependent to some extent on the surrounding river system. Another similarity is the adaptations made by plants and animals in both systems. Due to the presence of high water, plants and animals must adapt accordingly, as plants may need to keep their roots wet for months at a time (Flanagan 2021b).

2. Make a convincing argument for the preservation of riparian wetlands using their value to the natural world and ecosystem balance … then discuss their value to man’s quality of life.

Riparian wetlands are extremely valuable to the natural world for a multitude of reasons, and it is disappointing that so many have been destroyed for development or agricultural purposes in the United States. The rivers within riparian ecosystems use the land for nurseries, nutrient transfer, water storage, and lateral movement (Flanagan 2021a). Marshlands within these ecosystems store decent amounts of water, and also provide habitats for multiple flora and fauna. Floodplains specifically house many migratory birds, and are vital feeding stops/nesting areas to bird populations (Flanagan 2021a).

Riparian wetlands not only function as a way to improve the natural world, but they also improve quality of life for humans. Riparian systems offer benefits for agriculture practices, water quality, erosion control, and flood protection to name a few (Mitsch and Gosselink 2015, 492). Typically, these ecosystems are removed due to development and agriculture, but that does not need to be the case. We can use these systems to our advantage, rather than reshaping the natural landscape entirely.

3. How can we better live with wetlands? – or in a more sustainable fashion keeping wetland and human needs in balance.

In order to live alongside wetlands in a sustainable way, humans need to truly learn their benefits, and understand just how important they are to the functioning of ecosystems. The best way to accomplish this is through continued education and outreach. Through outreach and educational programs, the science and importance of wetlands can be explained in thorough detail. Growing up in Michigan, wetland education was actually part of my K-12 curriculum in my science classes. This was extremely helpful in my understanding of the importance of wetlands to the functioning of our world.

One organization that is doing an amazing job regarding wetland conservation education is Ducks Unlimited. The organization is a participant in the North American Waterfowl Management Plan, which has to date invested $7.5 billion to protect, restore or enhance acres upon acres of waterfowl habitat, mostly wetlands (Mitsch and Gosselink 2015, 523). These funds have been concentrated into the prairie pothole region, the lower Great Lakes–St. Lawrence River basin, and the Middle–Upper Atlantic Coastline (Mitsch and Gosselink 2015, 523).

4. View the video and discuss some of the characteristics of riparian wetlands found in the video with those discussed in the power points.

The video describes riparian wetlands as having the unique characteristic of death and regeneration, which cannot be duplicated by man. This regeneration is an essential part of the wetland lifecycle, and without it, they will not be sustained. The video also describes some vegetation, including cottonwoods, willows, and chokecherries, which are also mentioned in the PowerPoint as dominating vegetation in Colorado (Flanagan 2021b).

The video and PowerPoint both mention how we can best manage these wetlands while not totally sacrificing development or advancement. Both mention how engineering river systems has led to the destruction of these areas, and how the natural riparian ecosystems can actually be more beneficial (Flanagan 2021b; Flanagan 2021c). These systems need to be protected as they are very important to the functionality of the environment that they exist within.

References

Flannagan, Kathryn. 2021a. “Riparian Ecosystems Along Big Rivers.” Wetland Ecology and Management. Lecture, July 26. https://canvas.du.edu/courses/128480/pages/week-7-riparian-ecosystems-and-wetland-values-reading?module_item_id=2329229

Flannagan, Kathryn. 2021b. “Riparian Wetland Ecosystems.” Wetland Ecology and Management. Lecture, July 26. https://canvas.du.edu/courses/128480/pages/week-7-riparian-ecosystems-and-wetland-values-reading?module_item_id=2329229

Flannagan, Kathryn. 2021c. “Urban Deforestation.” Wetland Ecology and Management. Lecture, July 26. https://canvas.du.edu/courses/128480/pages/week-7-riparian-ecosystems-and-wetland-values-reading?module_item_id=2329229

Mitsch, William J., and James G. Gosselink. 2015. Wetlands. John Wiley & Sons, Inc.

My Comment:

Hi Kayla (Question 2),

The post mentions that riparian systems provide erosion control. I found a video that talks about consequences of stream bank erosion in unmaintained riparian zones and how to mitigate the erosion. It then suggests to plant trees next to the stream. Even though the natural erosion process will still happen, the woody roots of the planted trees and shrubs will capture the bank so that it cannot erode further. Also, overtime, there will be a graded stream bank that is more sustainable and reduce flooding potential. It even shows a scenario depicting a successful tree planting that achieved desired results overtime in terms of holding in the bank (even though the roots are exposed). However, it emphasized there needs to be rows of trees planted behind a single one so that as the erosion continues, restorationists can allow some trees to fall into the water and have others that still support the end goal.

Reference:

Alliance for Chesapeake Bay. 2020. “Riparian Restoration 101: Stream Restoration”.