Current Search: info:fedora/islandora:personCModel (x) » Department of Geosciences (x)
View All Items
(1 - 20 of 134)
Pages
- Title
- AN EXPLORATION OF THE SOCIODEMOGRAPHIC AND SOCIOECONOMIC DICHOTOMY OF SHRINKING CITIES AND FORMERLY SHRINKING CITIES IN THE CONTEXT OF THE BACK-TO-THE-CITY MOVEMENT.
- Creator
- Kittredge, Danielle J., Xie, Zhixiao, Florida Atlantic University, Department of Geosciences, Charles E. Schmidt College of Science
- Abstract/Description
-
Within the U.S. in recent decades a renewed interest in downtown and city living has become known as the “back-to-the-city movement” and contributed to the stabilization and regrowth of cities that were previously losing population. This trend, however, is not occurring equally and many cities within the U.S. that have been losing population for decades are still continuing to lose population (“shrinking city”). This study seeks to understand what sociodemographic and socioeconomic...
Show moreWithin the U.S. in recent decades a renewed interest in downtown and city living has become known as the “back-to-the-city movement” and contributed to the stabilization and regrowth of cities that were previously losing population. This trend, however, is not occurring equally and many cities within the U.S. that have been losing population for decades are still continuing to lose population (“shrinking city”). This study seeks to understand what sociodemographic and socioeconomic characteristics are contributing the greatest to the back-to-the-city movement and develop a composite index that can be used to identify if similar trends are beginning to emerge in shrinking cities. Variables identified through various literature for their association with back-to-the-city movement were analyzed through a proportion composition analysis comparing changes in growing versus non-growing census tracts at the city-wide and downtown level of 86 cities within this study. The analysis was conducted for the time periods of 1970 to 2017 and 1990 to 2017. The results justified variables for inclusion in back-to-the-city movement composite index, however, the analysis found some trends differed at the city-wide versus downtown geographic levels resulting in three potential index combinations. The three indices were calculated on census tracts for the 86 cities within this study and the results were decomposed to assess performance of individual variables. The results conclude that areas within some shrinking cities are exhibiting back-to-the-city movement trends, however, additional recommendations are provided for refining the index and methodology.
Show less - Date Issued
- 2020
- PURL
- http://purl.flvc.org/fau/fd/FA00013618
- Subject Headings
- Urban planning, Cities, Downtowns
- Format
- Document (PDF)
- Title
- Using Low-Cost Multi-Depth Samplers to Characterize the Variability of Specific Conductance in Coastal South Florida Beaches.
- Creator
- Shaver, Kyle David, Root, Tara, Briggs, Tiffany Roberts, Florida Atlantic University, Department of Geosciences, Charles E. Schmidt College of Science
- Abstract/Description
-
A small body of saline rich water rests in the saturated zone between the foredune and the shoreline at certain beaches. This region is beneath the water table and the top of the fresher groundwater, known as the Upper Saline Plume (USP). The USP is significant because density driven flow and chemical fluxes between freshwater, rainwater, and seawater contribute to biogeochemical processes in the subterranean estuary (Duque et al. 2020). The occurrence of the USP has been observed along...
Show moreA small body of saline rich water rests in the saturated zone between the foredune and the shoreline at certain beaches. This region is beneath the water table and the top of the fresher groundwater, known as the Upper Saline Plume (USP). The USP is significant because density driven flow and chemical fluxes between freshwater, rainwater, and seawater contribute to biogeochemical processes in the subterranean estuary (Duque et al. 2020). The occurrence of the USP has been observed along beaches that have a moderate to gentle slope, fine to medium grain size, and higher wave energy. The goal of this study was to determine if conditions for the presence of USP are consistent throughout different coastal beaches in southeast Florida while mapping the groundwater salinity across the beach. To identify the existence and delimit the boundary interface of the USP in the southeastern coast of Florida, multi–depth samplers were designed, built, and deployed along cross-shore transects at Jupiter and Gulfstream Beaches in Palm Beach County, FL. Groundwater samples were extracted along the transects to measure specific conductance. Although this study did not confirm the existence of the USP in South Florida beaches, an intermediate zone of water that is in-between the specific conductance ranges of relatively freshwater and relatively salty water was identified. Furthermore, the size of this intermediate zone was corresponded with beach slope, showing larger intermediate zones for steeper slopes and vice versa. Finally, temporal changes in the location and morphology of this intermediate zone were also identified in relation to a distinct disturbance event (Hurricane Isaias) which resulted in elevated ocean water levels.
Show less - Date Issued
- 2020
- PURL
- http://purl.flvc.org/fau/fd/FA00013625
- Subject Headings
- Beaches--Florida, Freshwater, Seawater, Water resources--Management
- 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
- MODELING GROUND ELEVATION OF LOUISIANA COASTAL WETLANDS AND ANALYZING RELATIVE SEA LEVEL RISE INUNDATION USING RSET-MH AND LIDAR MEASUREMENTS.
- Creator
- Liu, Jing, Zhang, Caiyun, Florida Atlantic University, Department of Geosciences, Charles E. Schmidt College of Science
- Abstract/Description
-
The Louisiana coastal ecosystem is experiencing increasing threats from human flood control construction, sea-level rise (SLR), and subsidence. Louisiana lost about 4,833 km2 of coastal wetlands from 1932 to 2016, and concern exists whether remaining wetlands will persist while facing the highest rate of relative sea-level rise (RSLR) in the world. Restoration aimed at rehabilitating the ongoing and future disturbances is currently underway through the implementation of the Coastal Wetlands...
Show moreThe Louisiana coastal ecosystem is experiencing increasing threats from human flood control construction, sea-level rise (SLR), and subsidence. Louisiana lost about 4,833 km2 of coastal wetlands from 1932 to 2016, and concern exists whether remaining wetlands will persist while facing the highest rate of relative sea-level rise (RSLR) in the world. Restoration aimed at rehabilitating the ongoing and future disturbances is currently underway through the implementation of the Coastal Wetlands Planning Protection and Restoration Act of 1990 (CWPPRA). To effectively monitor the progress of projects in CWPPRA, the Coastwide Reference Monitoring System (CRMS) was established in 2006. To date, more than a decade of valuable coastal, environmental, and ground elevation data have been collected and archived. This dataset offers a unique opportunity to evaluate the wetland ground elevation dynamics by linking the Rod Surface Elevation Table (RSET) measurements with environmental variables like water salinity and biophysical variables like canopy coverage. This dissertation research examined the effects of the environmental and biophysical variables on wetland terrain elevation by developing innovative machine learning based models to quantify the contribution of each factor using the CRMS collected dataset. Three modern machine learning algorithms, including Random Forest (RF), Support Vector Machine (SVM), and Artificial Neural Network (ANN), were assessed and cross-compared with the commonly used Multiple Linear Regression (MLR). The results showed that RF had the best performance in modeling ground elevation with Root Mean Square Error (RMSE) of 10.8 cm and coefficient of coefficient (r) = 0.74. The top four factors contributing to ground elevation are the distance from monitoring station to closest water source, water salinity, water elevation, and dominant vegetation height.
Show less - Date Issued
- 2020
- PURL
- http://purl.flvc.org/fau/fd/FA00013568
- Subject Headings
- Coastal zone management--Louisiana, Sea level rise, Inundations, Wetland restoration--Louisiana, Machine learning, Computer simulation, Algorithms.
- Format
- Document (PDF)
- Title
- COMBINING TRADITIONAL AND IMAGE ANALYSIS TECHNIQUES FOR UNCONSOLIDATED EXPOSED TERRIGENOUS BEACH SAND CHARACTERIZATION.
- Creator
- Smith, Molly Elizabeth, Zhang, Caiyun, Oleinik, Anton, Florida Atlantic University, Department of Geosciences, Charles E. Schmidt College of Science
- Abstract/Description
-
Traditional sand analysis is labor and cost-intensive, entailing specialized equipment and operators trained in geological analysis. Even a small step to automate part of the traditional geological methods could substantially improve the speed of such research while removing chances of human error. Digital image analysis techniques and computer vision have been well developed and applied in various fields but rarely explored for sand analysis. This research explores capabilities of remote...
Show moreTraditional sand analysis is labor and cost-intensive, entailing specialized equipment and operators trained in geological analysis. Even a small step to automate part of the traditional geological methods could substantially improve the speed of such research while removing chances of human error. Digital image analysis techniques and computer vision have been well developed and applied in various fields but rarely explored for sand analysis. This research explores capabilities of remote sensing digital image analysis techniques, such as object-based image analysis (OBIA), machine learning, digital image analysis, and photogrammetry to automate or semi-automate the traditional sand analysis procedure. Here presented is a framework combining OBIA and machine learning classification of microscope imagery for use with unconsolidated terrigenous beach sand samples. Five machine learning classifiers (RF, DT, SVM, k-NN, and ANN) are used to model mineral composition from images of ten terrigenous beach sand samples. Digital image analysis and photogrammetric techniques are applied and evaluated for use to characterize sand grain size and grain circularity (given as a digital proxy for traditional grain sphericity). A new segmentation process is also introduced, where pixel-level SLICO superpixel segmentation is followed by spectral difference segmentation and further levels of superpixel segmentation at the object-level. Previous methods of multi-resolution and superpixel segmentation at the object level do not provide the level of detail necessary to yield optimal sand grain-sized segments. In this proposed framework, the DT and RF classifiers provide the best estimations of mineral content of all classifiers tested compared to traditional compositional analysis. Average grain size approximated from photogrammetric procedures is comparable to traditional sieving methods, having an RMSE below 0.05%. The framework proposed here reduces the number of trained personnel needed to perform sand-related research. It requires minimal sand sample preparation and minimizes user-error that is typically introduced during traditional sand analysis.
Show less - Date Issued
- 2020
- PURL
- http://purl.flvc.org/fau/fd/FA00013517
- Subject Headings
- Sand, Image analysis, Remote sensing, Photogrammetry--Digital techniques, Machine learning
- Format
- Document (PDF)
- Title
- CONTROLS ON ARSENIC CONCENTRATIONS IN GROUNDWATER AT A FORMER GOLF COURSE IN BOCA RATON, FLORIDA.
- Creator
- Watson, D.S. Monty, Root, Tara L., Florida Atlantic University, Department of Geosciences, Charles E. Schmidt College of Science
- Abstract/Description
-
Arsenic is a known carcinogen, but is persistent in the environment, remaining a popular pesticide. It represents a particular hazard to humans when it stays resident in shallow soils and groundwater. This study of contaminant hydrogeology examined conditions at a former golf course in Florida with known arsenic contamination, and included a detailed examination of existing assessment data for the study area, an experimental pumping test with groundwater sampling, examination of sediment...
Show moreArsenic is a known carcinogen, but is persistent in the environment, remaining a popular pesticide. It represents a particular hazard to humans when it stays resident in shallow soils and groundwater. This study of contaminant hydrogeology examined conditions at a former golf course in Florida with known arsenic contamination, and included a detailed examination of existing assessment data for the study area, an experimental pumping test with groundwater sampling, examination of sediment cores, and a preliminary geophysical investigation. The primary purpose was to determine what the existing controls are on As mobility. The primary findings were that redox conditions did have an effect on As concentrations. Groundwater in the study area is generally reducing, but during the pumping test was generally oxidizing. No potential As sources were definitively identified, and the most likely source remains anthropogenic, but interactive conditions with Fe, Mn, NO3-N, and S remain nebulous.
Show less - Date Issued
- 2020
- PURL
- http://purl.flvc.org/fau/fd/FA00013574
- Subject Headings
- Hydrogeology--Florida, Boca Raton (Fla), Groundwater--Arsenic content, Arsenic--Analysis
- Format
- Document (PDF)
- Title
- EVALUATING UNMANNED AIRCRAFT SYSTEM PHOTOGRAMMETRY FOR COASTAL FLORIDA EVERGLADES RESTORATION AND MANAGEMENT.
- Creator
- Durgan, Sara D., Zhang, Caiyun, Florida Atlantic University, Department of Geosciences, Charles E. Schmidt College of Science
- Abstract/Description
-
The Florida Everglades ecosystem is experiencing increasing threats from anthropogenic modification of water flow, spread of invasive species, sea level rise (SLR), and more frequent and/or intense hurricanes. Restoration efforts aimed at rehabilitating these ongoing and future disturbances are currently underway through the implementation of the Comprehensive Everglades Restoration Plan (CERP). Efficacy of these restoration activities can be further improved with accurate and site-specific...
Show moreThe Florida Everglades ecosystem is experiencing increasing threats from anthropogenic modification of water flow, spread of invasive species, sea level rise (SLR), and more frequent and/or intense hurricanes. Restoration efforts aimed at rehabilitating these ongoing and future disturbances are currently underway through the implementation of the Comprehensive Everglades Restoration Plan (CERP). Efficacy of these restoration activities can be further improved with accurate and site-specific information on the current state of the coastal wetland habitats. In order to produce such assessments, digital datasets of the appropriate accuracy and scale are needed. These datasets include orthoimagery to delineate wetland areas and map vegetation cover as well as accurate 3-dimensional (3-D) models to characterize hydrology, physiochemistry, and habitat vulnerability.
Show less - Date Issued
- 2020
- PURL
- http://purl.flvc.org/fau/fd/FA00013501
- Subject Headings
- Everglades (Fla )--Environmental conditions--Remote sensing, Aerial photogrammetry, Wetland restoration--Florida--Everglades, Image analysis, Aerial photogrammetry--Data processing, Drone aircraft
- Format
- Document (PDF)
- Title
- UTILITY-SCALE SOLAR ENERGY FACILITIES, FLORIDA PANTHER HABITAT CONNECTIVITY, AND DISPERSAL CORRIDORS.
- Creator
- Leskova, Olena V., Markwith, Scott, Florida Atlantic University, Department of Geosciences, Charles E. Schmidt College of Science
- Abstract/Description
-
The objective of this research was to study the impacts of large USSE facilities on wildlife movement corridors and habitat connectivity in Florida to identify important habitat patches and movement corridors significant for potential Florida panther (Puma concolor coryi) dispersal, conservation, and recovery. Large carnivores (such as Florida panther) have often been examined as conservation umbrellas for large-scale connectivity planning due to their extensive spatial requirements (Beier et...
Show moreThe objective of this research was to study the impacts of large USSE facilities on wildlife movement corridors and habitat connectivity in Florida to identify important habitat patches and movement corridors significant for potential Florida panther (Puma concolor coryi) dispersal, conservation, and recovery. Large carnivores (such as Florida panther) have often been examined as conservation umbrellas for large-scale connectivity planning due to their extensive spatial requirements (Beier et al., 2006, Thorne et al., 2006). In addition, Florida panther is relatively well-studied species that have been listed as endangered under the US Endangered Species Act for over 40 years, due to habitat fragmentation and reduction. Habitat suitability was compared before and after the installation of the USSE facilities using RandomForest model developed by Frakes and Knight (in prep). The connectivity study focused on comparing current density and effective resistance (resistance distance) before and after the installations of USSE facilities and was conducted using Circuitscape 4.0. The impacts on habitat connectivity were the most substantial in the areas where the USSE facilities were installed on or around wildlife corridors, near focal areas, and in large clusters. The study has identified important linkages and new pathways that animals may try to take in order to bypass the facilities. The study has also shown that installation of USSE facilities in areas not suitable as habitat for Florida panthers, but still permeable or semi-permeable (e.g., agricultural lands), can substantially impact connectivity between focal areas.
Show less - Date Issued
- 2020
- PURL
- http://purl.flvc.org/fau/fd/FA00013500
- Subject Headings
- Florida panther, Puma concolor coryi, Habitat conservation, Solar energy--Environmental aspects, Solar energy--Florida
- Format
- Document (PDF)
- Title
- AN INVESTIGATION INTO THE NURSERY EFFECT OF SELECT REEF FISHES ALONG THE SOUTHERN FLORIDA COAST.
- Creator
- Pressly, Andrew, Hindle, Tobin, Florida Atlantic University, Department of Geosciences, Charles E. Schmidt College of Science
- Abstract/Description
-
The nursery effect is a process where juvenile fish utilize coastal habitats to help them survive before moving to their adult habitat. This process establishes an important link between marine ecosystems. This study examines the nursery effect and nursery habitat utilization in the Indian River Lagoon and Florida Bay systems, and the coral reefs adjacent to them. Quantitative and spatial techniques were utilized to identify patterns of presence and abundance and the size structure of select...
Show moreThe nursery effect is a process where juvenile fish utilize coastal habitats to help them survive before moving to their adult habitat. This process establishes an important link between marine ecosystems. This study examines the nursery effect and nursery habitat utilization in the Indian River Lagoon and Florida Bay systems, and the coral reefs adjacent to them. Quantitative and spatial techniques were utilized to identify patterns of presence and abundance and the size structure of select fish species. Spatial analyses were also used to investigate distribution patterns. Findings from this study suggest that several species utilize to a high degree the Indian River Lagoon and Florida Bay as nurseries. Furthermore, the abundance of adults on coral reefs is strongly connected to the presence of nurseries. This study has implications in fisheries management such as locating where juveniles of species develop. With such knowledge, better management plans could be implemented to ensure healthy fish stocks.
Show less - Date Issued
- 2020
- PURL
- http://purl.flvc.org/fau/fd/FA00013490
- Subject Headings
- Reef fishes, Florida Bay (Fla ), Indian River (Fla : Lagoon), Fisheries management, Marine nurseries
- Format
- Document (PDF)
- Title
- 2009-2010 Program Review Geosciences.
- Creator
- Florida Atlantic University, Department of Geosciences, Charles E. Schmidt College of Science
- Abstract/Description
-
Florida Atlantic University Departmental Dashboard Indicators. Department program reviews for Charles E. Schmidt College of Science, Florida Atlantic University.
- Date Issued
- 2009-2010
- PURL
- http://purl.flvc.org/fau/fd/FA00007675
- Format
- Document (PDF)
- Title
- 2010-2011 Program Review Geosciences.
- Creator
- Florida Atlantic University, Department of Geosciences, Charles E. Schmidt College of Science
- Abstract/Description
-
Florida Atlantic University Departmental Dashboard Indicators. Department program reviews for Charles E. Schmidt College of Science, Florida Atlantic University.
- Date Issued
- 2010-2011
- PURL
- http://purl.flvc.org/fau/fd/FA00007682
- Format
- Document (PDF)
- Title
- 2012-2013 Program Review Geosciences.
- Creator
- Florida Atlantic University, Department of Geosciences, Charles E. Schmidt College of Science
- Abstract/Description
-
Florida Atlantic University Departmental Dashboard Indicators. Department program reviews for Charles E. Schmidt College of Science, Florida Atlantic University.
- Date Issued
- 2012-2013
- PURL
- http://purl.flvc.org/fau/fd/FA00007689
- Format
- Document (PDF)
- Title
- 2013-2014 Program Review Geosciences.
- Creator
- Florida Atlantic University, Department of Geosciences, Charles E. Schmidt College of Science
- Abstract/Description
-
Florida Atlantic University Departmental Dashboard Indicators. Department program reviews for Charles E. Schmidt College of Science, Florida Atlantic University.
- Date Issued
- 2013-2014
- PURL
- http://purl.flvc.org/fau/fd/FA00007696
- Format
- Document (PDF)
- Title
- 2014-2015 Program Review Geosciences.
- Creator
- Florida Atlantic University, Department of Geosciences, Charles E. Schmidt College of Science
- Abstract/Description
-
Florida Atlantic University Departmental Dashboard Indicators. Department program reviews for Charles E. Schmidt College of Science, Florida Atlantic University.
- Date Issued
- 2014-2015
- PURL
- http://purl.flvc.org/fau/fd/FA00007703
- Format
- Document (PDF)
- Title
- 2015-2016 Program Review Geosciences.
- Creator
- Florida Atlantic University, Department of Geosciences, Charles E. Schmidt College of Science
- Abstract/Description
-
Florida Atlantic University Departmental Dashboard Indicators. Department program reviews for Charles E. Schmidt College of Science, Florida Atlantic University.
- Date Issued
- 2015-2016
- PURL
- http://purl.flvc.org/fau/fd/FA00007710
- Format
- Document (PDF)
- Title
- 2016-2017 Program Review Geosciences.
- Creator
- Florida Atlantic University, Department of Geosciences, Charles E. Schmidt College of Science
- Abstract/Description
-
Florida Atlantic University Departmental Dashboard Indicators. Department program reviews for Charles E. Schmidt College of Science, Florida Atlantic University.
- Date Issued
- 2016-2017
- PURL
- http://purl.flvc.org/fau/fd/FA00007717
- Format
- Document (PDF)
- Title
- DEVELOPMENT AND APPLICATION OF METHODS FOR STABLE WATER ISOTOPE SAMPLING FROM A LOW GRADIENT CANAL.
- Creator
- Greathouse, Jesse N., Root, Tara, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Geosciences
- Abstract/Description
-
Stable isotopes of water are used as tracers for characterizing surface water/groundwater interactions. Gaps in sampling protocol for these tracers in low gradient canals limits their use in studies of canal-groundwater exchanges. Several sampling methods were developed to determine the temporal and spatial isotopic variation in a canal. The influence of a flow control gate on isotopic composition and the sensitivity of isotope mixing calculations to choice of sampling method were also...
Show moreStable isotopes of water are used as tracers for characterizing surface water/groundwater interactions. Gaps in sampling protocol for these tracers in low gradient canals limits their use in studies of canal-groundwater exchanges. Several sampling methods were developed to determine the temporal and spatial isotopic variation in a canal. The influence of a flow control gate on isotopic composition and the sensitivity of isotope mixing calculations to choice of sampling method were also evaluated. There was little variability in the isotopic composition of the canal along a cross section perpendicular flow. Some variation occurred monthly and seasonally. The greatest variability occurred between the upstream and downstream side of the flow control gates when the gates were closed. Mixing calculations were not sensitive to the choice of sampling method. This study shed light on isotope sampling methods in canals for canal-groundwater interactions studies.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013313
- Subject Headings
- Stable isotope tracers, Environmental sampling--Methodology, Water--Sampling--Technique, Canals--Florida
- Format
- Document (PDF)
- Title
- EVALUATION OF LOCAL OFFSHORE SEDIMENTS FOR COASTAL RESTORATION PROJECTS IN PALM BEACH COUNTY, FL, USA.
- Creator
- Palaparthi, Jyothirmayi, Briggs, Tiffany Roberts, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Geosciences
- Abstract/Description
-
Open-coast beach-dune environments are vulnerable to erosion, such as from storms or interruption of littoral drift. Although protected from event-driven wave energy, backbarrier shorelines are also susceptible to erosion, due to tidal currents and boat wakes. A common response to mitigate erosion is to place sediment and restore the environment. For placement on beaches, a significant effort has been made to identify offshore resources available; however, offshore resources have seldom been...
Show moreOpen-coast beach-dune environments are vulnerable to erosion, such as from storms or interruption of littoral drift. Although protected from event-driven wave energy, backbarrier shorelines are also susceptible to erosion, due to tidal currents and boat wakes. A common response to mitigate erosion is to place sediment and restore the environment. For placement on beaches, a significant effort has been made to identify offshore resources available; however, offshore resources have seldom been considered for dune or backbarrier shoreline restoration. This study evaluates the geotechnical sediment properties of offshore sediments in proven borrow areas for beach nourishment and reclassifies them for placement in dunes and along the backbarrier in Palm Beach County, Florida. Two different methods calculate volume of offshore resources available for dune or backbarrier projects, including numerical calculations and interpolation of volume through SURFER. Because existing proven borrow areas are delineated for beach nourishment, less volume of sediment available in these areas for other coastal environments. The results of this study suggest that identifying offshore sediment sources for lower-energy environments would not adversely impact sediment needed for beach nourishment. As coastal environments are increasingly threatened by climate change and sea level rise, sediment resources become scarcer, the need to efficiently and effectively use sediments will be of utmost importance for scientists, engineers, and managers in their efforts to protect coastal habitat and communities.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013337
- Subject Headings
- Sedimentation and deposition, Coastal erosion, Palm Beach County (Fla ), Sediments (Geology)--Analysis, Dunes, Coastal restoration
- Format
- Document (PDF)
- Title
- Mapping the Fresh-Saltwater Transition Zone Across the Beach Environment Using Ground-Penetrating Radar (GPR).
- Creator
- Becker, Joseph Michael, Roberts Briggs, Tiffany, Comas, Xavier, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Geosciences
- Abstract/Description
-
As sea level rises, saltwater migration can threaten coastal ecosystems and beach-dune environments, which negatively impacts coastal flora. This study uses ground penetrating radar (GPR) to evaluate the spatiotemporal variability of saltwater migration in the near shore at high lateral resolution (i.e. cm) by using daily micro tidal cycles as analogs to infer saltwater migration. Time-lapse GPR profiles were collected at low and high tide capturing phase lags of the tidal flux through...
Show moreAs sea level rises, saltwater migration can threaten coastal ecosystems and beach-dune environments, which negatively impacts coastal flora. This study uses ground penetrating radar (GPR) to evaluate the spatiotemporal variability of saltwater migration in the near shore at high lateral resolution (i.e. cm) by using daily micro tidal cycles as analogs to infer saltwater migration. Time-lapse GPR profiles were collected at low and high tide capturing phase lags of the tidal flux through different substrates. GPR measurements were collected at two sites in Miami with contrasting lithologies: a) Crandon Park, composed of unconsolidated sand; and b) the Barnacle Historic State Park, composed of the Miami Limestone Formation. Laboratory-scale GPR measurements were collected over samples mimicking field conditions. The results may be helpful to identify regions vulnerable to saltwater migration in the near shore based on lithological variability, and to mitigate negative impacts for flora in beach-dune habitats during sea level rise.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013183
- Subject Headings
- Ground penetrating radar, Saltwaters, Seashore ecology, Coastal ecology
- Format
- Document (PDF)
- Title
- High Spatial Resolution Measurements Using Hydrogeophysical Methods Reveal the Presence of Hotspots forBbiogenic Gas Accumulation and Release in the Florida Everglades.
- Creator
- Bole, Troy, Comas, Xavier, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Geosciences
- Abstract/Description
-
It is well known that biogenic gas emissions (mainly methane and carbon dioxide) vary both spatially and temporally in peatlands. While most studies have focused on northern systems, several recent studies in tropical and subtropical peatlands (like the Everglades) have revealed the presence of areas of increased gas accumulation and emissions, or hotspots, that may be related to physical and/or biogeochemical changes within the peat's matrix. However, these studies are often limited in terms...
Show moreIt is well known that biogenic gas emissions (mainly methane and carbon dioxide) vary both spatially and temporally in peatlands. While most studies have focused on northern systems, several recent studies in tropical and subtropical peatlands (like the Everglades) have revealed the presence of areas of increased gas accumulation and emissions, or hotspots, that may be related to physical and/or biogeochemical changes within the peat's matrix. However, these studies are often limited in terms of sampling volume and resolution or are based in laboratory studies that may not be totally representative of field conditions. In this study we investigate the spatial variability (both lateral and vertical) in gas accumulation and release at the field scale, over 10 m long transects at two locations in Water Conservation Area 1 of the Florida Everglades, using an array of hydrogeophysical methods. Resulting data infers the presence of hotspots with dimensions ranging from 1-2 m in width and approximately 0.5 m tall. These areas showed high variations in biogenic gas accumulation and release an order of magnitude higher than surrounding areas and occur seasonally as the highest gas releases were observed during Florida’s wet season. This study therefore has implications for better understanding the spatial and temporal variability of biogenic gas hotspots in peat soils, and how the matrix structure affects gas accumulation and release. This study shows the importance of considering the heterogenous nature of the peat's matrix when quantifying gas fluxes in the Everglades, and particularly when using methods with small sampling volumes like gas chambers.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013189
- Subject Headings
- Everglades (Fla. ), Biogenic gas, Peatlands, Measurement
- Format
- Document (PDF)
