Original Post by Lauren Winter:
You are the manager of a Wildlife and Wetland Refuge on the Ashepoo River in South Carolina. The Corps of Engineers would like to build a dam on the Ashepoo River and you need to make a convincing argument as to how that would affect your refuge which consists of domed peat forests and tidal freshwater marshes. These wetlands would be flooded by the reservoir. Use the info I gave you in the PowerPoint and your reading to list why this action would destroy your wetlands.
Both domed peat forests and tidal freshwater marshes require specific hydroperiods for their survival. Permanently flooding the wetlands would destroy them a few different ways. Wetlands require peat accumulation, and the introduction of water and sediment would instead erode the edges, change the nutrient levels and begin the process of decomposition (Mitsch and Gosselink 2015). This in turn causes the loss of soil and plants. Over time, this would cause the peat to erode and become unstable, eventually collapsing and causing the habitat to become uninhabitable for wildlife.
2. Explain the connection between dry and wet cycles of alluvial cypress swamps using both websites and the Cypress PowerPoint. How long can a swamp stay dry? What is the best cycle for cypress-tupelo forest health and regeneration? How does the hydrology feed the plant life of swamps?
Alluvial cypress swamps have a distinct wet and dry period, with dry periods occurring every decade or so. Wet and dry cycles are necessary for the influx of nutrients as well as continuous oxygenation. When they are drained or when the dry period is extended significantly, they may be invaded by pine, ash, maple, or hardwood species (Mitsch and Gosselink 2015).
The most optimal cycle is regular flooding (advantageous for seed dispersal), mixed with occasional fires along the edges of the swamp. This re-introduces nutrients back into the system, and fire selectively kills pine and hardwood species that would otherwise be competing for resources against the cypress trees (Mitsch and Gosselink 2015).
Cypress and water tupelo are wetland plants that produce pneumatophores, which are organs that extend from the root system underwater to above the water level. This helps to increase oxygen uptake (EPA. n.d)
Compare bogs and fens:
How are they alike?
Bogs and fens are both peat forming wetlands that: prevents or reduces the risk of flood, improves water quality, and provides habitat. They are both primarily found the Northeastern and Great Lakes regions of the United States (“Nematodes of the Sandhills Fens.” n.d.), though fens extend to the Rocky Mountains and into Canada.
How are they different?
Bogs receive almost all of their water through precipitation, while fens receive nutrients from other sources such as groundwater and runoff.
Bogs are acidic, poorly oxygenated, and low in nutrients needed for plant growth, while fens are less acidic, well oxygenated, and have higher nutrient levels (Flanagan, K. ppt. n.d.).
Bogs host carnivorous plants, reptiles, and amphibians, but few fish. Fens are often covered with grasses, sedges, and wildflowers. (Flanagan, K. ppt. n.d.).
Choose either a bog or fen and discuss how you would restore this ecosystem that was degraded by human activities (can be mining, development, agricultural etc.)
Restoring a bog or fen degraded by human activity would likely require an evaluation of the native plant life, soil, and water health. Restoring any issues with the water table would be necessary for the continued health and function of the wetland over the long term. Any dams or drainage ditches would be removed, and berms or backfill ditches may need to be constructed to improve irrigation. To reduce the load of pesticides/herbicides in the soil, the top soil would be removed and replaced. Lastly, reconnect floodplains to reduce sediment load and downstream flooding.
References:
EPA. n.d. “Classification and Types of Wetlands” Accessed July 20, 2021. https://www.epa.gov/wetlands/classification-and-types-wetlands#fens (Links to an external site.) (Links to an external site.) (Links to an external site.).
Flannagan, Kathryn. 2021. ““Freshwater Swamps – Cypress/Tupelo Alluvial Swamps”.” Wetland Ecology and Management. Lecture, July 19. https://canvas.du.edu/courses/128480/pages/week-6-peatlands-and-forested-swamps-reading?module_item_id=2329226
Flannagan, Kathryn. 2021. ““Peatlands of South Carolina”.” Wetland Ecology and Management. Lecture, July 19. https://canvas.du.edu/courses/128480/pages/week-6-peatlands-and-forested-swamps-reading?module_item_id=2329226
Mitsch, William J., and James G. Gosselink. 2015. Wetlands. John Wiley & Sons, Inc.
“Nematodes of the Sandhills Fens.” n.d. About the Fens. Accessed July 19, 2021. https://nematode.unl.edu/fensabout.htm (Links to an external site.)
My Comment:
Hi Lauren (Questions 3),
I found a specific example expanding on your recommended restoration strategy to “improve irrigation”. The example is from Pocosin Lakes National Wildlife Refuge. Since the Refuge was established, the U.S. Fish and Wildlife Service and partners have been working to reestablish the natural hydrology of the Pocosin Lakes region. The project involves installing levees and water control structures to stop the drainage of water from the soil, while still allowing soil moisture to fluctuate naturally as a result of rainfall and evaporation (Nature4Climate, n.d.).
In terms of additional strategy, researchers are also comparing carbon emissions in restored and unrestored areas of the refuge, collecting information that will support peatland restoration efforts elsewhere in the world (Nature4Climate, n.d.). This approach is a great strategy to advocate for resources to go towards wetland restoration. By illustrating wetland degradation as a carbon emissions problem, it can help the issue gain attention and frame the problems in a way that anybody who understands global warming can comprehend. Considering the dried peat also spawned large wildfires in 1985 and 2008 (Nature4Climate, n.d.), communicating wetland degradation as a wildlife safety hazard can also help generate a sense of urgency to restore a peatland.
Reference:
Nature4Climate. n.d. “Peatland Restoration- Case Study: Pocosin Lakes National Wildlife Refuge”. “https://nature4climate.org/science/n4c-pathways/wetlands/peatland-restoration/Original Post by Lauren Winter:
You are the manager of a Wildlife and Wetland Refuge on the Ashepoo River in South Carolina. The Corps of Engineers would like to build a dam on the Ashepoo River and you need to make a convincing argument as to how that would affect your refuge which consists of domed peat forests and tidal freshwater marshes. These wetlands would be flooded by the reservoir. Use the info I gave you in the PowerPoint and your reading to list why this action would destroy your wetlands.
Both domed peat forests and tidal freshwater marshes require specific hydroperiods for their survival. Permanently flooding the wetlands would destroy them a few different ways. Wetlands require peat accumulation, and the introduction of water and sediment would instead erode the edges, change the nutrient levels and begin the process of decomposition (Mitsch and Gosselink 2015). This in turn causes the loss of soil and plants. Over time, this would cause the peat to erode and become unstable, eventually collapsing and causing the habitat to become uninhabitable for wildlife.
2. Explain the connection between dry and wet cycles of alluvial cypress swamps using both websites and the Cypress PowerPoint. How long can a swamp stay dry? What is the best cycle for cypress-tupelo forest health and regeneration? How does the hydrology feed the plant life of swamps?
Alluvial cypress swamps have a distinct wet and dry period, with dry periods occurring every decade or so. Wet and dry cycles are necessary for the influx of nutrients as well as continuous oxygenation. When they are drained or when the dry period is extended significantly, they may be invaded by pine, ash, maple, or hardwood species (Mitsch and Gosselink 2015).
The most optimal cycle is regular flooding (advantageous for seed dispersal), mixed with occasional fires along the edges of the swamp. This re-introduces nutrients back into the system, and fire selectively kills pine and hardwood species that would otherwise be competing for resources against the cypress trees (Mitsch and Gosselink 2015).
Cypress and water tupelo are wetland plants that produce pneumatophores, which are organs that extend from the root system underwater to above the water level. This helps to increase oxygen uptake (EPA. n.d)
Compare bogs and fens:
How are they alike?
Bogs and fens are both peat forming wetlands that: prevents or reduces the risk of flood, improves water quality, and provides habitat. They are both primarily found the Northeastern and Great Lakes regions of the United States (“Nematodes of the Sandhills Fens.” n.d.), though fens extend to the Rocky Mountains and into Canada.
How are they different?
Bogs receive almost all of their water through precipitation, while fens receive nutrients from other sources such as groundwater and runoff.
Bogs are acidic, poorly oxygenated, and low in nutrients needed for plant growth, while fens are less acidic, well oxygenated, and have higher nutrient levels (Flanagan, K. ppt. n.d.).
Bogs host carnivorous plants, reptiles, and amphibians, but few fish. Fens are often covered with grasses, sedges, and wildflowers. (Flanagan, K. ppt. n.d.).
Choose either a bog or fen and discuss how you would restore this ecosystem that was degraded by human activities (can be mining, development, agricultural etc.)
Restoring a bog or fen degraded by human activity would likely require an evaluation of the native plant life, soil, and water health. Restoring any issues with the water table would be necessary for the continued health and function of the wetland over the long term. Any dams or drainage ditches would be removed, and berms or backfill ditches may need to be constructed to improve irrigation. To reduce the load of pesticides/herbicides in the soil, the top soil would be removed and replaced. Lastly, reconnect floodplains to reduce sediment load and downstream flooding.
References:
EPA. n.d. “Classification and Types of Wetlands” Accessed July 20, 2021. https://www.epa.gov/wetlands/classification-and-types-wetlands#fens (Links to an external site.) (Links to an external site.) (Links to an external site.).
Flannagan, Kathryn. 2021. ““Freshwater Swamps – Cypress/Tupelo Alluvial Swamps”.” Wetland Ecology and Management. Lecture, July 19. https://canvas.du.edu/courses/128480/pages/week-6-peatlands-and-forested-swamps-reading?module_item_id=2329226
Flannagan, Kathryn. 2021. ““Peatlands of South Carolina”.” Wetland Ecology and Management. Lecture, July 19. https://canvas.du.edu/courses/128480/pages/week-6-peatlands-and-forested-swamps-reading?module_item_id=2329226
Mitsch, William J., and James G. Gosselink. 2015. Wetlands. John Wiley & Sons, Inc.
“Nematodes of the Sandhills Fens.” n.d. About the Fens. Accessed July 19, 2021. https://nematode.unl.edu/fensabout.htm (Links to an external site.)
My Comment:
Hi Lauren (Questions 3),
I found a specific example expanding on your recommended restoration strategy to “improve irrigation”. The example is from Pocosin Lakes National Wildlife Refuge. Since the Refuge was established, the U.S. Fish and Wildlife Service and partners have been working to reestablish the natural hydrology of the Pocosin Lakes region. The project involves installing levees and water control structures to stop the drainage of water from the soil, while still allowing soil moisture to fluctuate naturally as a result of rainfall and evaporation (Nature4Climate, n.d.).
In terms of additional strategy, researchers are also comparing carbon emissions in restored and unrestored areas of the refuge, collecting information that will support peatland restoration efforts elsewhere in the world (Nature4Climate, n.d.). This approach is a great strategy to advocate for resources to go towards wetland restoration. By illustrating wetland degradation as a carbon emissions problem, it can help the issue gain attention and frame the problems in a way that anybody who understands global warming can comprehend. Considering the dried peat also spawned large wildfires in 1985 and 2008 (Nature4Climate, n.d.), communicating wetland degradation as a wildlife safety hazard can also help generate a sense of urgency to restore a peatland.
Reference:
Nature4Climate. n.d. “Peatland Restoration- Case Study: Pocosin Lakes National Wildlife Refuge”. “https://nature4climate.org/science/n4c-pathways/wetlands/peatland-restoration/