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- Title
- The tobacco range fracture zone: a unique system of slumped mangrove peat.
- Creator
- Littler, Mark M., Littler, Diane S., MacIntyre, I. G., Brooks, Barrett L., Taylor, P. R., Lapointe, Brian E.
- Date Issued
- 1995
- PURL
- http://purl.flvc.org/fau/fd/FA00007098
- Subject Headings
- Belize, Mangrove, Peat, Thalassia testudinum
- Format
- Document (PDF)
- Title
- EFFECTS OF SALTWATER INTRUSION ON THE COMPRESSIBILITY BEHAVIOR OF THE EVERGLADES SOILS.
- Creator
- Ribeiro, Camila, Sobhan, Khaled, Florida Atlantic University, Department of Civil, Environmental and Geomatics Engineering, College of Engineering and Computer Science
- Abstract/Description
-
The Florida Everglades is considered as a vulnerable wetland composed primary of organic rich peat soils, experiencing saltwater intrusion. Impact of increasing salinity on the strength and deformation properties of peat is unknown. A laboratory study was undertaken to evaluate how the growing salinity level due to sea level rise may alter the compressibility behavior of the Everglades soils. Sixteen 1-dimensional oedometer tests were conducted on undisturbed Everglades peat soils in two...
Show moreThe Florida Everglades is considered as a vulnerable wetland composed primary of organic rich peat soils, experiencing saltwater intrusion. Impact of increasing salinity on the strength and deformation properties of peat is unknown. A laboratory study was undertaken to evaluate how the growing salinity level due to sea level rise may alter the compressibility behavior of the Everglades soils. Sixteen 1-dimensional oedometer tests were conducted on undisturbed Everglades peat soils in two phases. Phase I included samples from Site 1 (saltwater) and Site 3 (freshwater) without any salinity addition. Phase II consisted of soil from Site 3 (freshwater) saturated in six different levels of salinity artificially added to the samples. Compressibility properties investigated in this study include compression index (Cc), coefficient of consolidation (Cv), hydraulic conductivity (K), and the Ca/Cc ratio. In general, it was observed that the increase in salinity beyond a threshold value tends to increase the soil compressibility properties, indicating a possible reduction in soil stability with saltwater intrusion.
Show less - Date Issued
- 2021
- PURL
- http://purl.flvc.org/fau/fd/FA00013783
- Subject Headings
- Everglades (Fla.), Peat soils, Saltwater encroachment, Compressibility
- Format
- Document (PDF)
- Title
- INVESTIGATING THE EFFECTS OF SEA-LEVEL RISE AND INCREASED SALINITY ON PEAT SOILS OF THE EVERGLADES (FLORIDA): IMPLICATIONS FOR CHANGES IN BIOGENIC GAS DYNAMICS AND PEAT COLLAPSE.
- Creator
- Sirianni, Matthew J., Comas, Xavier, Florida Atlantic University, Department of Geosciences, Charles E. Schmidt College of Science
- Abstract/Description
-
While repeated transgressive and regressive sea level cycles have shaped south Florida throughout geological history, modern rates of sea level rise pose a significant risk to the structure and function of the freshwater wetland ecosystems throughout the low-lying Everglades region. Current regionally corrected sea level projections for south Florida indicate a rise of 0.42m by 2050 and 1.15m by 2100, suggesting the salinization of previously freshwater areas of the Everglades is conceivable....
Show moreWhile repeated transgressive and regressive sea level cycles have shaped south Florida throughout geological history, modern rates of sea level rise pose a significant risk to the structure and function of the freshwater wetland ecosystems throughout the low-lying Everglades region. Current regionally corrected sea level projections for south Florida indicate a rise of 0.42m by 2050 and 1.15m by 2100, suggesting the salinization of previously freshwater areas of the Everglades is conceivable. As freshwater areas become increasingly exposed to saltwater they experience shifts in vegetation composition, soil microbial populations, plant productivity, and physical soil properties that ultimately result in a phenomenon called peat collapse. Recent work in the Everglades has sought to further explain the mechanisms of peat collapse, however the physical changes to the peat matrix induced by saltwater intrusion are still uncertain. Moreover, the combination of physical alterations to the peat matrix associated with peat collapse and shifts in wetland salinity regimes will also likely disrupt the current carbon gas dynamics of the Everglades.
Show less - Date Issued
- 2020
- PURL
- http://purl.flvc.org/fau/fd/FA00013589
- Subject Headings
- Sea level rise, Peat soils, Everglades (Fla)
- Format
- Document (PDF)
- Title
- Cascading effects of vegetation on peat soil properties and crayfish survival in the Florida Everglades.
- Creator
- Chapman, Alexander, Benscoter, Brian, Dorn, Nathan, Graduate College
- Date Issued
- 2013-04-12
- PURL
- http://purl.flvc.org/fcla/dt/3361281
- Subject Headings
- Everglades (Fla.), Peat soils, Crayfish, Cattails, Multitrophic interactions (Ecology)
- Format
- Document (PDF)
- Title
- FIRE BEHAVIOR ACROSS A VEGETATION GRADIENT AND PEAT COMBUSTION VULNERABILITY IN SOUTH FLORIDA.
- Creator
- Jensen, Kevin, Benscoter, Brian, Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
- Abstract/Description
-
Fire is a tool to reduce fuel and restore ecosystems but poses a risk of peat combustion that temporally restricts managers. Studies indicate that fires may be prescribed with a water table lower than the peat surface, but are based on locations with different peat properties or assumed heat inputs. The goal of this research is to quantify peat surface heating during a passing fire and the heat required to ignite peat under lowered water tables. This study used temperature probes at two...
Show moreFire is a tool to reduce fuel and restore ecosystems but poses a risk of peat combustion that temporally restricts managers. Studies indicate that fires may be prescribed with a water table lower than the peat surface, but are based on locations with different peat properties or assumed heat inputs. The goal of this research is to quantify peat surface heating during a passing fire and the heat required to ignite peat under lowered water tables. This study used temperature probes at two heights to quantify peat surface heating during a prescribed fire and a manipulative experiment to quantify the effects of water table recession on peat properties important for predicting ignition. The soil surface experienced 87% of the flaming heat in sawgrass dominated areas. The heat required to ignite the peat surface was significantly correlated with the water table depth. This provides managers greater opportunity for prescribing fire.
Show less - Date Issued
- 2021
- PURL
- http://purl.flvc.org/fau/fd/FA00013780
- Subject Headings
- Fires, Fire ecology, Peat--Combustion, Prescribed burning
- Format
- Document (PDF)
- Title
- CHANGES IN PHYSICAL PROPERTIES OF THE PEAT SOIL MATRIX ACROSS A SALINITY GRADIENT IN THE EVERGLADES: IMPLICATIONS FOR ACCELERATING PEAT COLLAPSE DURING SEA LEVEL RISE.
- Creator
- Florey, Maxwell, Comas, Xavier, Florida Atlantic University, Department of Geosciences, Charles E. Schmidt College of Science
- Abstract/Description
-
Peatlands are areas with an accumulated layer of peat soil that are considered global stores of carbon, acting as a net sink of carbon dioxide and a net source of methane. Recent studies in coastal peatlands have shown how that a rise in sea level may contribute to the degradation of peat soils due to the inland progression of the saltwater interface, which may result in physical changes within the peat matrix that may eventually result in peat collapse. For example, earlier studies in boreal...
Show morePeatlands are areas with an accumulated layer of peat soil that are considered global stores of carbon, acting as a net sink of carbon dioxide and a net source of methane. Recent studies in coastal peatlands have shown how that a rise in sea level may contribute to the degradation of peat soils due to the inland progression of the saltwater interface, which may result in physical changes within the peat matrix that may eventually result in peat collapse. For example, earlier studies in boreal peat soils described the effect of pore dilation as a result of increased salinity in peat soils, while recent studies in Everglades peat soils showed specific salinity thresholds that may represent a permanent loss of the structural integrity of the peat matrix that may represent early stages of peat collapse. While most of these previous efforts have focused on drivers, recent work has also explored conceptual models to better understand the mechanisms inducing peat collapse. However, few datasets exists that consistently compare differences in physical properties under different ināsitu salinity conditions. In this study differences in the physical properties of peat soils across a salinity gradient along the western edge of Big Cypress National Preserve are investigated to test how differences in salinity may induce physical changes in the soil matrix. The physical properties targeted for this study include porosity, hydraulic conductivity, and carbon content. Measurements are conducted at the laboratory scale using peat cores and monoliths collected at selected locations to investigate: 1) how overall soil physical properties change spatially over a salinity gradient at the km scale moving from permanently saline to freshwater conditions; and 2) how physical properties change spatially at specific sites as dependant on vegetation boundaries and proximity to collapsed soils. This study has implications for better understanding the potential relation between physical changes of the soil matrix and the phenomena of peat collapse in the Everglades as saltwater intrusion progresses inward and alters freshwater ecosystems. Furthermore, a better mechanistic understanding of the peat collapse phenomenon can potentially help mitigate its occurrence.
Show less - Date Issued
- 2021
- PURL
- http://purl.flvc.org/fau/fd/FA00013809
- Subject Headings
- Peat soils, Salinity, Sea level, Big Cypress National Preserve (Fla.), Everglades (Fla.)
- Format
- Document (PDF)
- Title
- Investigating biogenic gas dynamics from peat soils of the Everglades using hydrogeophysical methods.
- Creator
- Wright, William J., Comas, Xavier, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Geosciences
- Abstract/Description
-
Peat soils are known to be a significant emitter of atmospheric greenhouse gasses. However, the spatial and temporal variability in production and release of greenhouse gases (such as methane) in peat soils remains uncertain, particularly for low-latitude peatlands like the Florida Everglades, as the majority of studies on gas dynamics in peatlands focus on northern peatlands. The purpose of the work outlined here is focused on understanding the spatial and temporal variability in biogenic...
Show morePeat soils are known to be a significant emitter of atmospheric greenhouse gasses. However, the spatial and temporal variability in production and release of greenhouse gases (such as methane) in peat soils remains uncertain, particularly for low-latitude peatlands like the Florida Everglades, as the majority of studies on gas dynamics in peatlands focus on northern peatlands. The purpose of the work outlined here is focused on understanding the spatial and temporal variability in biogenic gas dynamics (i.e. production and release of methane and carbon dioxide) by implementing various experiments in the Florida Everglades at different scales of measurement, using noninvasive hydrogeophysical methods. Non-invasive methods include ground-penetrating radar (GPR), gas traps, time-lapse cameras, and hydrostatic pressure head measurements, that were constrained with direct measurements on soil cores like porosity, and gas composition using gas chromatography. By utilizing the measurements of in-situ gas volumes, we are able to estimate gas production using a mass balance approach, explore spatial and temporal variabilities of gas dynamics, and better constrain gas ebullition models. A better understanding of the spatial and temporal variability in gas production and release in peat soils from the Everglades has implications regarding the role of subtropical wetlands in the global carbon cycle, and can help providing better production and flux estimates to help global climate researchers improve their predictions and models for climate change.
Show less - Date Issued
- 2018
- PURL
- http://purl.flvc.org/fau/fd/FA00013146
- Subject Headings
- Peat soils, Gas dynamics, Carbon cycle (Biogeochemistry), Everglades (Fla), Biogenic gas
- Format
- Document (PDF)