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Changes In Tundra Plant And Soil Organic Geochemical Composition In Response To Long-Term Increased Winter Precipitation In N. Alaska, Olivia Miller

Open Access Theses

Tundra ecosystem soils store half of the global soil organic carbon (SOC) pool and have the potential to release large amounts of greenhouse gases, primarily CH₄ and CO₂. As climates warm and permafrost thaws, the emissions of these gases as organic matter decomposition rates increase may become increasingly important to the chemistry of the atmosphere. Increases in precipitation that accompany warming, may shift tundra vegetative composition from moss/graminoid- to shrub-dominated systems. These vegetation shifts may result in important feedback effects as altered plant and litter chemistry may affect SOC storage in soils. Questions investigated include: 1) How …

Systematic Analysis Of Drainage Events In Free Draining And Managed Subsurface Drainage Systems, Guy Bou Lahdou

Open Access Theses

Understanding the hydrologic controls that regulate outflow from free and managed subsurface drainage systems during drainage events can offer improved insight on the overall functioning and effectiveness of the systems so that they can be better managed or retrofitted to increase their environmental benefits. This study used drainage, precipitation, water table, and soil moisture data from a monitoring site located in east central Indiana to investigate the event hydrology of 22 drainage events in free and managed subsurface drainage systems. Relationships between event drainage volume, drain flow hydrograph metrics, column soil moisture, water table depth, and precipitation characteristics were explored …

Application Of The Savitzky-Golay Filter To Land Cover Classification Using Temporal Modis Vegetation Indices, So-Ra Kim, Anup K. Prasad, Hesham El-Askary, Woo- Kyun Lee, Doo- Ahn Kwak, Seung- Ho Lee, Menas Kafatos

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

In this study, the Savitzky-Golay filter was applied to smooth observed unnatural variations in the temporal profiles of the Normalized Difference Vegetation Index (NDVI} and the Enhanced Vegetation Index {EVI} time series from the MODerate Resolution Imaging Spectroradiometer (MODIS}. We computed two sets of land cover classifications based 011 the NDVI and EVI time series before and after applying the Savitzky-Golay filter. The resulting classification from the filtered versions of the vegetation indices showed a substantial improvement in accuracy when compared to the classifications from the unfiltered versions. The classification by the EVIsg had the highest K (0.72} for all …

Effective Geoscience Pedagogy At The Undergraduate Level, Kelsey Warden

Open Access Theses

This investigation used constructivist pedagogical methods within the framework of an introductory level undergraduate geoscience course to gauge both the changes in attitude and cognition of students. Pedagogy was modified in the laboratory setting, but maintained in the lecture setting and homework. Curriculum was also maintained in the lecture, but was changed in the laboratory to emphasize the large concepts and systems stressed in Earth Science Literacy Principles. Student understanding of these concepts and systems was strengthened by factual knowledge, but recall and memorization were not the goal of the laboratory instruction. The overall goal of the study was to …

Use Of System Dynamics Modeling To Explicate The Theory-Of-Change Of A Social Marketing Innovation, Brian J. Biroscak

USF Tampa Graduate Theses and Dissertations

Community coalitions are an important part of the public health milieu and thus subject to many of the same external pressures as public health organizations--including changes in required strategic orientation. Many funding agencies have shifted their funding agenda from program development to policy change. Thus, the Florida Prevention Research Center created the Community-Based Prevention Marketing for Policy Development framework to teach community coalitions how to apply social marketing to policy change. The dissertation research reported here was designed to explicate the framework's theory-of-change. The research question was: "What are the linkages and connections between CBPM inputs, activities, immediate outcomes, intermediate …

Organic Copper Binding Ligands And Thiol Compounds Produced By Bacteria And In The Elizabeth River, Virginia, Christina Louise Dryden

OES Theses and Dissertations

This dissertation presents work focusing on copper and organic copper binding ligands in laboratory cultures and the Elizabeth River, Virginia. Laboratory cultures of the marine bacterium Vibrio parahaemolyticus were used to demonstrate the influence of elevated copper concentrations on copper-complexing ligand and thiol production. Copper-complexing ligands similar in binding strength to the strongest natural ligands were detected in V. parahaemolyticus cultures (log K′_CuL = 11.8–13.2). A strong correlation (r² = 0.973) was found between total thiol and copper-complexing ligand concentrations at all copper concentrations examined.

A yearlong seasonal study was undertaken in a heavily polluted estuary to ascertain …

Implications Of Climate Change For Cyanobacteria Over The Western Florida Shelf In The Gulf Of Mexico, Ivy Mara Ozmon

OES Theses and Dissertations

Concentrations of atmospheric CO₂ are expected to double by year 2100 as a result of anthropogenic activities. Under elevated CO₂ conditions, cyanobacteria may reallocate energy from active accumulation and transport of dissolved inorganic carbon (C) required for photosynthesis to other growth processes. Stimulation of cyanobacterial production on the Western Florida Shelf in the Gulf of Mexico (GOM) could lead to improved nutritional status for the toxic, mixotrophic dinoflagellate Karenia brevis that utilizes newly fixed N₂ from co-occurring diazotrophic cyanobacteria and consumes unicellular cyanobacteria via grazing for growth. Culture studies performed by other researchers on the climate induced …

A Comprehensive Evaluation Of C25 Highly Branched Isoprenoid Alkenes Of Marine Diatoms As Proxies For Sea Ice Extent In The Arctic Ocean, Tetiana Muniak

OES Theses and Dissertations

Sea Ice extent is one of the major factors regulating carbon cycling and ecosystem function in the modern Arctic Ocean. It is an essential component of climate models and is crucial for the evaluation of various oceanographic processes that influence a particular region. Yet it is also one of the most difficult attributes of the ocean with respect to our ability for its accurate reconstruction from paleo records. The lack of the detailed records prior to satellite information has encouraged the development of new proxy records for the reconstruction of past

sea ice conditions. In recent years, a new monounsaturated …

A Multi-Proxy Approach To Understanding Abrupt Climate Change And Laurentide Ice Sheet Melting History Based On Gulf Of Mexico Sediments, Clare Carlisle Williams

USF Tampa Graduate Theses and Dissertations

During the last deglaciation (ca. 24-10 ka thousand years ago (ka)), the North American Laurentide Ice Sheet (LIS) was a major source of meltwater to the Arctic Ocean, North Atlantic Ocean, and the Gulf of Mexico (GOM), and it is hypothesized that meltwater routing played an important role in regulating Late Quaternary millennial-scale climate variability, via its influence on Atlantic Meridional Overturning Circulation (AMOC). For example, the meltwater routing hypothesis predicts that a rerouting of meltwater from the GOM to the North Atlantic and/or Arctic Oceans resulted in a decrease of North Atlantic Deep Water (NADW) formation and subsequent cooling …

Evolution And Equilibration Of Artificial Morphologic Perturbations In The Form Of Nearshore Berm Nourishments Along The Florida Gulf Coast, Katherine Emily Brutsché

USF Tampa Graduate Theses and Dissertations

Inlets and channels are dredged often to maintain navigation safety. It is beneficial to reintroduce the dredged material back into the littoral system, in the form of beach or nearshore nourishments. Nourishment in the nearshore is becoming an increasingly utilized method, particularly for dredged material that contains more fine sediment than the native beach. This research examines the morphologic evolution of two different nearshore nourishments. A nearshore berm was constructed at Fort Myers Beach, Florida using mixed-sized sediment dredged from a nearby channel. The nearshore berm was placed in water depths between 1.2 and 2.4 m with the berm crest …

P‐Nexfs Analysis Of Aerosol Phosphorus Delivered To The Mediterranean Sea, Amelia F. Longo, Ellery D. Ingall, Julia M. Diaz, Michelle Oakes, Laura E. King, Athanasios Nenes, Nikolaos Mihalopoulos, Kaliopi Violaki, Anna Avila, Claudia R. Benitez-Nelson, Jay Brandes, Ian Mcnulty, David J. Vine

Faculty Publications

Biological productivity in many ocean regions is controlled by the availability of the nutrient phosphorus. In the Mediterranean Sea, aerosol deposition is a key source of phosphorus and understanding its composition is critical for determining its potential bioavailability. Aerosol phosphorus was investigated in European and North African air masses using phosphorus near‐edge X‐ray fluorescence spectroscopy (P‐NEXFS). These air masses are the main source of aerosol deposition to the Mediterranean Sea. We show that European aerosols are a significant source of soluble phosphorus to the Mediterranean Sea. European aerosols deliver on average 3.5 times more soluble phosphorus than North African aerosols …

Macroinvertebrates And Excessive Fine Sediment Conditions In Oregon Coastal Streams, Patrick M. Edwards

Dissertations and Theses

The Pacific Coastal ecoregion contains large tracts of economically important forest lands that also serve as critical stream habitat for endangered Salmonids. Excessive fine sediment deposition in streams of this region is a major environmental concern in the region but difficult to measure directly. The use of stream invertebrates to monitor fine sediment conditions in streams requires careful consideration of several important factors that complicate their use as bioindicators including high spatial and temporal variability and covariance with other environmental variables.

To evaluate the use of stream invertebrates as bioindicators of excessive fine sediment, three hypotheses were tested. The first …

Facies Analysis, Sequence Stratigraphy And Paleogeography Of The Middle Jurassic (Callovian) Entrada Sandstone: Traps, Tectonics, And Analog, George R. Jennings Iii

Theses and Dissertations

The late Middle Jurassic (Callovian) Entrada Sandstone has been divided into two general facies associations consisting primarily of eolian sandstones in eastern Utah and "muddy" redbeds in central Utah. Sedimentary structures within the redbed portion are explained by the interfingering of inland sabkha, alluvial, and eolian depositional systems. A complete succession from the most basinward facies to the most terrestrial facies in the Entrada Sandstone consists of inland sabkha facies overlain by either alluvial or eolian facies. Where both alluvial and eolian facies interfinger, alluvial facies overlain by eolian facies is considered a normal succession. Sequence boundaries, often identified by …

Investigating Meter Scale Topographic Variation As A Factor Of Monterey Pine (Pinus Radiata) Growing Conditions At Kenneth Norris Rancho Marino Reserve, Cambria, Ca, William J. Meyst

Natural Resources Management and Environmental Sciences

Endemic Monterey pine (Pinus radiata) is limited to three locations in California due to its unique ecological requirements. This project was conducted to investigate spatial growth patterns ofMonterey pine over complex ground surfaces. The coastal hills of Rancho Marino Reserve, Cambria, were surveyed using four 150-m transects to quantify and record ground surface features and growing conditions ofMonterey pine. Changes in elevation of each transect were measured using an Abney level. Linear ground surfaces were found at 86% (344 of 400) of survey nodes. Convex ground surfaces were found at 10.5% of survey nodes (42 of 400). Of …

Sex-Biased Gene Flow Among Elk In The Greater Yellowstone Ecosystem, Brian K. Hand, Shanyuan Chen, Neil Anderson, Albano Beja-Pereira, Paul C. Cross, Michael Ebinger, Hank Edwards, Robert A. Garrott, Marty D. Kardos, Matt Kauffman, Erin L. Landguth, Arthur Middleton, Brandon Scurlock, P.J. White, Pete Zager, Michael K. Schwartz, Gordon Luikart

United States Geological Survey: Staff Publications

We quantified patterns of population genetic structure to help understand gene flow among elk populations across the Greater Yellowstone Ecosystem. We sequenced 596 base pairs of the mitochondrial control region of 380 elk from eight populations. Analysis revealed high mitochondrial DNA variation within populations, averaging 13.0 haplotypes with high mean gene diversity (0.85). The genetic differentiation among populations for mitochondrial DNA was relatively high (FST = 0.161; P = 0.001) compared to genetic differentiation for nuclear microsatellite data (FST = 0.002; P = 0.332), which suggested relatively low female gene flow among populations. The estimated ratio of male to female …

Predictive Modeling In The Search For Vertebrate Fossils: Geographic Object Based Image Analysis (Geobia) In The Eocene Of Wyoming, Bryan Bommersbach

Masters Theses

The development and testing of predictive models for identifying productive fossil localities represents a promising interdisciplinary endeavor among geographic information scientists, paleoanthropologists, and vertebrate paleontologists. This thesis analyzed high resolution (2m spatial resolution) commercial satellite imagery from the Worldview-2 satellite of five areas of the Great Divide Basin using a GEographic Object-Based Image Analysis (GEOBIA) technique, which segments the image into spectrally homogeneous, multi-pixel image objects. In addition to allowing statistical analysis of the spectral characteristics of the image objects, GEOBIA techniques also let analysts incorporate expert knowledge and contextual information to improve classification accuracy. The spectral characteristics of the …

Correlation And Paleoenvironments Above West T9.3 Tuff, Pisco Formation, Peru, Caleb Stanton

Loma Linda University Electronic Theses, Dissertations & Projects

The Pisco Basin is a Cenozoic forearc basin in west central Peru. Though outcrops are well exposed, contain little diagenetic overprint, or complex structural deformation, only rudimentary correlations between outcrops are published and no attempts have been made to define time-bounded subunits. The goal of this study is to develop high resolution-stratigraphy and paleoenvironmental interpretations for a time-bounded unit in the lower part of the Miocene Pisco Formation. In this study, we correlated, mapped, and dated a tuff couplet and associated beds over 25 km2. We measured eight sections that include the tuffs and conducted detailed facies analysis. Sections were …

Water In The 21st Century, Grayson Michael Shor

Social Sciences

The aim of this research project is to provide a comprehensive and global analysis of water use in order to provide the reader with a comprehensive grasp of current and impending issues. The included five (5) chapters discuss water distribution, conservation, purification, law, international development, economic debates, ethical consideration, as well as educated estimations of the effects water related issues may cause in the next one-hundred years.

The Evolution Of Respiratory O2/No Reductases: An Out-Of-The-Phylogenetic-Box Perspective, Anne-Lise Ducluzeau, Barbara Schoepp-Cothenet, Robert Van Lis, Frauke Baymann, Michael J. Russell, Wilfgang Nitschke

Department of Biochemistry: Faculty Publications

Complex life on our planet crucially depends on strong redox disequilibria afforded by the almost ubiquitous presence of highly oxidizing molecular oxygen. However, the history of O₂-levels in the atmosphere is complex and prior to the Great Oxidation Event some 2.3 billion years ago, the amount of O₂ in the biosphere is considered to have been extremely low as compared with present-day values. Therefore the evolutionary histories of life and of O₂-levels are likely intricately intertwined. The obvious biological proxy for inferring the impact of changing O₂-levels on life is the evolutionary history …

Exploring The Link Between Otolith Growth And Function Along The Biological Continuum In The Context Of Ocean Acidification, Eric D. Wilcox Freeburg

Graduate Doctoral Dissertations

Oceans are acidifying as atmospheric CO₂ is drawn down. This process, known as ocean acidification (OA), is well known and documented. Over the next 100 years, pH of the surface ocean is projected to decrease by up to 0.35 units. This CO₂ draw down has a direct effect on dissolved inorganic carbon (DIC) balance in the ocean. OA is expected to impact calcifying organisms that rely on constituencies of the DIC system, specifically carbonate ion [CO₃2-]. It is clear that externally calcified structures, such as coral skeletons, bivalve shells, etc., will be significantly affected as pH, …

The Effects Of Cold Adaptation On The Growth And Development Of The Neandertal Cranial Base, Sarah Caldwell

Theses and Dissertations

Neandertals and modern humans possess very different craniofacial shapes. Some recent work has attributed these contrasting shapes specifically to differences in brain development, which are extrapolated to mean differences in cognitive function. However, this may not necessarily be the case. In this paper, it is suggested that a size increase in the cranial base and rapid cranial growth are due not to cognitive differences, but environmental factors, specifically Neandertal adaptation to cold. Adaptation to cold would not only explain the more rapid growth of the Neandertal cranium, but also elongation of the cranial base via elongation of the nasopharynx for …

Geophysical Applications For Levee Assessment, Hussein Khalefa Chlaib

Theses and Dissertations

Levees are important engineering structures that build along the rivers to protect the human lives and shield the communities as well as agriculture lands from the high water level events. Animal burrows, subsurface cavities, and low density (high permeability) zones are weakness features within the levee body that increase its risk of failure. To prevent such failure, continuous monitoring of the structure integrity and early detection of the weakness features must be conducted. Application of Ground Penetrating Radar (GPR) and Capacitively Coupled Resistivity (CCR) methods were found to be very effective in assessing the levees and detect zones of weakness …

Dust Mediated Transfer Of Phosphorus To Alpine Lake Ecosystems Of The Wind River Range, Wyoming, Usa, Janice Brahney, Ashley P. Ballantyne, P. Kociolek, Sarah A. Spaulding, Megan Otu, T. Porwoll, Jason C. Neff

Watershed Sciences Faculty Publications

Alpine lakes receive a large fraction of their nutrients from atmospheric sources and are consequently sensitive to variations in both the amount and chemistry of atmospheric deposition. In this study we explored the spatial changes in lake water chemistry and biology along a gradient of dust deposition in the Wind River Range, Wyoming. Regional differences were explored using the variation in bulk deposition, lake water, sediment, and bedrock geochemistry and catchment characteristics. Dust deposition rates in the Southwestern region averaged 3.34 g m−2 year−1, approximately three times higher than deposition rates in the Northwestern region (average 1.06 g m−2 year−1). …

Carbon Sequestration In Tidal Salt Marshes And Mangrove Ecosystems, Carlos Eduardo Quintana-Alcantara

Master's Projects and Capstones

Wetlands are dynamic systems that provide support to vital environmental functions and services. Wetlands take part in the global carbon cycle by holding organic carbon in biomass, soils and sediments. In recent years, the wetland carbon sequestration capacity has been researched worldwide due to the increase of the concentrations of greenhouse gasses implicated in global warming and climate change. Although coastal wetlands release the greenhouse gasses carbon dioxide, methane and nitrous oxide, these ecosystems maintain high performance in offsetting significant amounts of atmospheric carbon. This paper investigated the carbon sequestration capacity of coastal wetland ecosystems summarizing the environmental conditions and …

Bacterial Migration Through Low-Permeability Fault Zones In Compartmentalised Aquifer Systems: A Case Study In Southern Italy, Antonio Bucci, Emma Petrella, Gino Naclerio, Sabrina Gambatese, Fulvio Celico

International Journal of Speleology

The aim of this study was to experimentally verify the significance of microbial transport through low-permeability fault zones in a compartmentalised carbonate aquifer system in Southern Italy.

The temporal variability of microbial communities in two springs fed by the same aquifer system, but discharging up- and down-gradient of two low-permeability fault zones, was analysed using a 16S rDNA polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE)-based approach. At both springs, a remarkable temporal variation in PCR-DGGE profiles was detected throughout the observation period. When comparing the PCR-DGGE profiles of the two springs, a synchronous evolution over time was observed. Moreover, the …

Water Water Everywhere: Analyzing Long Island's Water Issues And Finding Solutions For A Sustainable Future, Anthony T. Becker

2014 Student Theses

Over three million people call Long Island their home. With access to beautiful landscapes, world-renowned beaches, and proximity to New York City, it is no wonder that so many proudly call this geographic stretch of glacial till their home. However, throughout the years our actions do not necessarily reflect this affection we have to our home. Years of sprawl and human infestation across the island have resulted in widespread environmental degradation. Specifically, the water we drink and the beaches we enjoy have become endangered. I plan on studying the urban ecology of how intensified population growth led to the eutrophication …

From The Depths Of Great Pond (Maine): Anthropogenic And Natural Influences On Bottom Sediments And The Implications For Local Sustainability, Sara George, Clara Bicher

CLAS: Colby Liberal Arts Symposium

As part of a Maine EPSCoR grant focusing on sustainability in the Belgrade Lakes watershed of central Maine, current research consists of collecting bottom sediment samples from Great Pond. Samples were analyzed to create a sediment map of the lake basin in regards to depth, grain-size distribution, organic content (%C), C:N ratios and phosphorus concentration. Results will aid in the understanding of the glacial formation of the lake, distribution of sediment within, and human impact on the lake. Additionally, knowing the distribution of phosphorus within the sediments may allow development of a strategy to avoid accelerated eutrophication. This research will …

Impacts Of Carbonate Mineral Weathering On Hydrochemistry Of The Upper Green River Basin, Kentucky, Laura Leigh Osterhoudt

Masters Theses & Specialist Projects

Kentucky’s Upper Green River Basin has received significant attention due to the area’s high biodiversity and spectacular karst development. While carbonate bedrock is present throughout the watershed, it is more extensive and homogenous along the river between Greensburg and Munfordville than upstream from Greensburg where the geology is more heterogeneous. This research quantitatively evaluated how lithological differences between the two catchment areas impact hydrochemistry and inorganic carbon cycling. This first required correcting catchment boundaries on previous US Geological Survey Hydrologic Unit Maps to account for areas where the boundaries cross sinkhole plains. Basin boundaries using existing Kentucky Division of Water …

Watershed-Based Water Quality Management, Benjamin Barnett Witherell

Theses, Dissertations and Culminating Projects

In response to landscape alteration and increased knowledge of environmental systems, government regulation for the protection of water quality has undergone several adaptations since the landmark Clean Water Act of 1972. Most recently, in 2000, USEPA moved its emphasis from an effluent-based approach to an ambient or watershedbased approach. Prior watershed studies have uncovered relationships between the type of land cover in a watershed and water quality. These studies have generally indicated correlations between urbanized watersheds and degradation of water quality and aquatic ecosystem health. This dissertation is both an extension of these previous studies to the area of water …

Searching For Biogeochemical Hot Spots In Three Dimensions: Soil C And N Cycling In Hydropedologic Settings In A Northern Hardwood Forest, Jennifer L. Morse, S F. Werner, Cody P. Gillin, Christine L. Goodale, Scott W. Bailey, Kevin J. Mcguire, Peter M. Groffman

Environmental Science and Management Faculty Publications and Presentations

Understanding and predicting the extent, location, and function of biogeochemical hot spots at the watershed scale is a frontier in environmental science. We applied a hydropedologic approach to identify (1) biogeochemical differences among morphologically distinct hydropedologic settings and (2) hot spots of microbial carbon (C) and nitrogen (N) cycling activity in a northern hardwood forest in Hubbard Brook Experimental Forest, New Hampshire, USA. We assessed variables related to C and N cycling in spodic hydropedologic settings (typical podzols, bimodal podzols, and Bh podzols) and groundwater seeps during August 2010. We found that soil horizons (Oi/Oe, Oa/A, and B) differed significantly …