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Investigating biogenic gas dynamics from peat soils of the Everglades using hydrogeophysical methods
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.
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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)
Investigating variability of biogenic gas dynamics in peat soils using high temporal frequency hydrogeophysical methods
Title
Investigating variability of biogenic gas dynamics in peat soils using high temporal frequency hydrogeophysical methods.
Creator
Wright, William J., Charles E. Schmidt College of Science, Department of Geosciences
Abstract/Description
Peat soils are known to be a significant source of atmospheric greenhouse gasses. However, the releases of methane and carbon dioxide gasses from peat soils are currently not well understood, particularly since the timing of the releases are poorly constrained. Furthermore, most research work performed on peatlands has been focused on temperate to sub-arctic peatlands, while recent works have suggested that gas production rates from low-latitude peat soils are higher than those from colder...
Show morePeat soils are known to be a significant source of atmospheric greenhouse gasses. However, the releases of methane and carbon dioxide gasses from peat soils are currently not well understood, particularly since the timing of the releases are poorly constrained. Furthermore, most research work performed on peatlands has been focused on temperate to sub-arctic peatlands, while recent works have suggested that gas production rates from low-latitude peat soils are higher than those from colder climates. The purpose of the work proposed here is to introduce an autonomous Ground Penetrating Radar (GPR) method for investigating the timing of gas releases from peat soils at the lab scale utilizing samples originating from Maine and the Florida Everglades, and at the field scale in a Maine peatland. Geophysical data are supported by direct gas flux measurements using the flux chamber method enhanced by timelapse photography, and terrestrial LiDAR (TLS) monitoring surface deformation.
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Date Issued
2013
PURL
http://purl.flvc.org/fcla/dt/3361256
Subject Headings
Gas dynamics, Wetland ecology, Soil permeability, Estuarine sediments, Ground penetrating radar, Hydrogeology, Geophysics
Format
Document (PDF)
Biogenic gas dynamics in peat soil blocks using ground penetrating radar: a comparative study in the laboratory between peat soils from the Everglades and from two northern peatlands in Minnesota and Maine
Title
Biogenic gas dynamics in peat soil blocks using ground penetrating radar: a comparative study in the laboratory between peat soils from the Everglades and from two northern peatlands in Minnesota and Maine.
Creator
Cabolova, Anastasija., Charles E. Schmidt College of Science, Department of Physics
Abstract/Description
Peatlands cover a total area of approximately 3 million square kilometers and are one of the largest natural sources of atmospheric methane (CH4) and carbon dioxide (CO2). Most traditional methods used to estimate biogenic gas dynamics are invasive and provide little or no information about lateral distribution of gas. In contrast, Ground Penetrating Radar (GPR) is an emerging technique for non-invasive investigation of gas dynamics in peat soils. This thesis establishes a direct comparison...
Show morePeatlands cover a total area of approximately 3 million square kilometers and are one of the largest natural sources of atmospheric methane (CH4) and carbon dioxide (CO2). Most traditional methods used to estimate biogenic gas dynamics are invasive and provide little or no information about lateral distribution of gas. In contrast, Ground Penetrating Radar (GPR) is an emerging technique for non-invasive investigation of gas dynamics in peat soils. This thesis establishes a direct comparison between gas dynamics (i.e. build-up and release) of four different types of peat soil using GPR. Peat soil blocks were collected at peatlands with contrasting latitudes, including the Everglades, Maine and Minnesota. A unique two-antenna GPR setup was used to monitor biogenic gas buildup and ebullition events over a period of 4.5 months, constraining GPR data with surface deformation measurements and direct CH4 and CO2 concentration measurements. The effect of atmospheric pressure was also investigated. This study has implications for better understanding global gas dynamics and carbon cycling in peat soils and its role in climate change.
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Date Issued
2010
PURL
http://purl.flvc.org/FAU/2974433
Subject Headings
Wetland ecology, Wetland ecology, Wetland ecology, Gas dynamics, Soil permeability, Ground penetrating radar, Porous materials, Fluid dynamics
Format
Document (PDF)
Understanding Variability of Biogenic Gas Fluxes from Peat Soils at High Temporal Resolution Using Capacitance Moisture Probes
Title
Understanding Variability of Biogenic Gas Fluxes from Peat Soils at High Temporal Resolution Using Capacitance Moisture Probes.
Creator
Munzenrieder, Cali, Comas, Xavier, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Geosciences
Abstract/Description
Peatlands act as carbon sinks while representing major sources of biogenic gases such as methane (CH4) and carbon dioxide (CO2), two potent greenhouse gases. Gas production and release in these peats soils are also influenced by overall warm temperatures and water table fluctuations due to the naturally shallow water table in the Florida Everglades. Releases of biogenic gases from Florida Everglades peat soils are not well understood and the temporal distribution and dynamics are uncertain....
Show morePeatlands act as carbon sinks while representing major sources of biogenic gases such as methane (CH4) and carbon dioxide (CO2), two potent greenhouse gases. Gas production and release in these peats soils are also influenced by overall warm temperatures and water table fluctuations due to the naturally shallow water table in the Florida Everglades. Releases of biogenic gases from Florida Everglades peat soils are not well understood and the temporal distribution and dynamics are uncertain. The general objective of this work was geared towards a methodological approach which aimed to examine the feasibility of capacitance moisture probes to investigate biogenic gas dynamics in various Florida Everglades peat soils at high temporal resolution. This work has implications for establishing capacitance moisture probes as a method to monitor gas dynamics in peat soils at high temporal resolution and better understanding patterns of gas build-up and release from peat soils in the Everglades.
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Date Issued
2016
PURL
http://purl.flvc.org/fau/fd/FA00004700
Subject Headings
Everglades National Park (Fla.) -- Environmental conditions, Gas dynamics, Geographic information systems, Grassland ecology, Greenhouse gases, Wetland ecology
Format
Document (PDF)