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Full-Text Articles in Entire DC Network
Interpolating Beach Profile Data Using Linear And Non-Linear Functions, Lance Calloway Croft
Interpolating Beach Profile Data Using Linear And Non-Linear Functions, Lance Calloway Croft
USF Tampa Graduate Theses and Dissertations
ABSTRACT
Beach and nearshore surveys are conducted in a variety of ways, the most commonly used being the level-and-transit method; because it is inexpensive, time conducive and highly accurate. Specifically, beach surveys are conducted to better understand cross-shore, long-shore sediment transport processes, as well as to quantify volume changes, which are used to evaluate beach performance. In this study, a section of the beach on Sand Key, FL was surveyed using rod-and-transit. In addition to the commonly used linear data analysis, a non-linear analysis was conducted using NURBS (Non-Uniform Rational B-Splines).
Survey data was collected within a short time window …
Droughtscape, Summer 2014, Kelly Smith
Droughtscape, Summer 2014, Kelly Smith
DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)
Contents
Director’s report
Outlook
Drought & climate summary
Drought impacts
International drought monitoring and planning
Visiting scholars
North American Drought Monitor Forum
New primary Dust Bowl source
New additions to online webinar archive
Community Capitals Framework Institute
Effective Geoscience Pedagogy At The Undergraduate Level, Kelsey Warden
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 …
Assessing The Archaeological Resources Of Mormon Nauvoo With Three-Dimensional Geophysical Imaging, John H. Mcbride
Assessing The Archaeological Resources Of Mormon Nauvoo With Three-Dimensional Geophysical Imaging, John H. Mcbride
Journal of Undergraduate Research
The principal objective of the project was to provide BYU students with the experience of exploring Nauvoo using ground-penetrating radar (GPR) in order to gain a better appreciation of early Mormon history from a geophysical and archaeological perspective. The objective was met by carrying out two field seasons in Nauvoo. In addition, the grant partially funded a field expedition to the LDS Far West Burying Grounds and Hawn’s Mill sites in Missouri in order to perform surveying work analogous to that performed in Nauvoo. Additional funding for this project was provided by the LDS Church History Department, which allowed more …
A Comprehensive Evaluation Of C25 Highly Branched Isoprenoid Alkenes Of Marine Diatoms As Proxies For Sea Ice Extent In The Arctic Ocean, Tetiana Muniak
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 …
Rapid Reservoir Erosion, Hyperconcentrated Flow, And Downstream Deposition Triggered By Breaching Of 38 M Tall Condit Dam, White Salmon River, Washington, Andrew C. Wilcox, Jim E. O'Connor, Jon J. Major
Rapid Reservoir Erosion, Hyperconcentrated Flow, And Downstream Deposition Triggered By Breaching Of 38 M Tall Condit Dam, White Salmon River, Washington, Andrew C. Wilcox, Jim E. O'Connor, Jon J. Major
Geosciences Faculty Publications
Condit Dam on the White Salmon River,Washington, a 38m high dam impounding a large volume (1.8 million m3) of fine-grained sediment (60% sand, 35% silt and clay, and 5% gravel), was rapidly breached in October 2011. This unique dam decommissioning produced dramatic upstream and downstream geomorphic responses in the hours and weeks following breaching. Blasting a 5 m wide hole into the base of the dam resulted in rapid reservoir drawdown, abruptly releasing ~1.6 million m3 of reservoir water, exposing reservoir sediment to erosion, and triggering mass failures of the thickly accumulated reservoir sediment. Within 90 min …
The University Of Nebraska State Museum, Robert F. Diffendal Jr.
The University Of Nebraska State Museum, Robert F. Diffendal Jr.
Robert F. Diffendal, Jr., Publications
I first walked through the doors of Morrill Hall on the main or City Campus of the University of Nebraska on a day late in August of 1962 and thought that I had entered paleontology heaven. Morrill Hall then housed the University of Nebraska State Museum (UNSM). most of the Geology Department, and some other parts of university units. I was a new graduate student hoping to pursue research in invertebrate paleontology in the Department of Geology and was on my way to see the department chairman for the first time. When I entered the building I walked through a …
Dust And Pleistocene Ice Ages: Eolian Sediments And Climate Change At Ziegler Reservoir, Snowmass Village, Colorado, Jeffrey S. Honke
Dust And Pleistocene Ice Ages: Eolian Sediments And Climate Change At Ziegler Reservoir, Snowmass Village, Colorado, Jeffrey S. Honke
Electronic Theses and Dissertations
The discovery of the Ziegler Reservoir fossil site near Snowmass Village, Colorado presents an opportunity to examine subalpine ecosystem response, during a relatively unknown period, in which climate conditions were similar to present. Finegrained sediments at Ziegler Reservoir represent continuous deposition between ~140–55 ka (thousand years before present), spanning the close of the Bull Lake glacial period [marine isotope stage (MIS) 6], the Sangamon interglacial (MIS 5) and the early stages of the Pinedale (early Wisconsin) glacial period (MIS 4). Ziegler Reservoir is positioned on top of a ridge, at an elevation of 2705 m, and has a small watershed …
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
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 …
Late Quaternary Faulting History Of The Carrizal And Related Faults, La Paz Region, Baja California Sur, Mexico, Paul J. Umhoefer, Sara J. Maloney, Beverly Buchanan, J. Ramón Arrowsmith, Genaro Martinez-Gutiérrez, Graham Kent, Neal Driscoll, Alistair Harding, Darrell Kaufman, Tammy M. Rittenour
Late Quaternary Faulting History Of The Carrizal And Related Faults, La Paz Region, Baja California Sur, Mexico, Paul J. Umhoefer, Sara J. Maloney, Beverly Buchanan, J. Ramón Arrowsmith, Genaro Martinez-Gutiérrez, Graham Kent, Neal Driscoll, Alistair Harding, Darrell Kaufman, Tammy M. Rittenour
Geosciences Faculty Publications
The southwest margin of the Gulf of California has an array of active normal faults despite this being an oblique-divergent plate boundary with spreading centers that localized deformation along the plate boundary 2–3 million years ago. The Carrizal and Centenario faults form the western border fault of the Gulf of California marginal fault system within and south of La Paz Bay, and ∼20–30 km west of the capital city of La Paz, Baja California Sur, Mexico. Geologic and geomorphic mapping, optically stimulated luminescence (OSL) geochronology, and paleoseismic investigations onshore, compressed high-intensity radar pulse (CHIRP) profiling offshore, and analysis of uplifted …
Predictive Modeling In The Search For Vertebrate Fossils: Geographic Object Based Image Analysis (Geobia) In The Eocene Of Wyoming, Bryan Bommersbach
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 …
Water In The 21st Century, Grayson Michael Shor
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.
Geophysical Applications For Levee Assessment, Hussein Khalefa Chlaib
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 …
Usability Testing: Open Geoportal 2.0, Rob Wolff, Kristin Parker
Usability Testing: Open Geoportal 2.0, Rob Wolff, Kristin Parker
PLACE Project
The PLACE project team at the University of New Hampshire Library performed usability testing on May 9, 2014 with three participants with GIS experience. Tasks focused on use of Open GeoPortal 2.0 (beta).
Carbon Sequestration In Tidal Salt Marshes And Mangrove Ecosystems, Carlos Eduardo Quintana-Alcantara
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 …
Water Water Everywhere: Analyzing Long Island's Water Issues And Finding Solutions For A Sustainable Future, Anthony T. Becker
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 …
Combining Quantitative Eye-Tracking And Gis Techniques With Qualitative Research Methods To Evaluate The Effectiveness Of 2d And Static, 3d Karst Visualizations: Seeing Through The Complexities Of Karst Environments, Elizabeth Katharyn Tyrie
Combining Quantitative Eye-Tracking And Gis Techniques With Qualitative Research Methods To Evaluate The Effectiveness Of 2d And Static, 3d Karst Visualizations: Seeing Through The Complexities Of Karst Environments, Elizabeth Katharyn Tyrie
Masters Theses & Specialist Projects
Karst environments are interconnected landscapes vulnerable to degradation. Many instances of anthropogenic karst disturbance are unintentional, and occur because of the public's lack of understanding or exposure to karst knowledge. When attempts are made to educate the general public about these landscapes, the concepts taught are often too abstract to be fully understood. Thus, karst educational pursuits must use only the most efficient and effective learning materials. A technique useful for assessing educational effectiveness of learning materials is eye-tracking, which allows scientists to quantitatively measure an individual's points of interest and eye movements when viewing a 2D or 3D visualization. …
Are Droughts Becoming More Frequent Or Severe In China Based On The Standardized Precipitation Evapotranspiration Index: 1951–2010?, Meixiu Yu, Qiongfang Li, Michael J. Hayes, Mark Svoboda, Richard R. Heim Jr.
Are Droughts Becoming More Frequent Or Severe In China Based On The Standardized Precipitation Evapotranspiration Index: 1951–2010?, Meixiu Yu, Qiongfang Li, Michael J. Hayes, Mark Svoboda, Richard R. Heim Jr.
National Drought Mitigation Center: Faculty Publications
The Standardized Precipitation Evapotranspiration Index (SPEI) was computed based on the monthly precipitation and air temperature values at 609 locations over China during the period 1951–2010.Various characteristics of drought across China were examined including: long-term trends, percentage of area affected, intensity, duration, and drought frequency. The results revealed that severe and extreme droughts have become more serious since late 1990s for all of China (with dry area increasing by ∼3.72% per decade); and persistent multi-year severe droughts were more frequent in north China, northeast China, and western northwest China; significant drying trends occurred over north China, the southwest region of …
Summer River Water Temperature Changes In The Musconetcong River And Their Potential Impact On Aquatic Habitat, Joseph Anthony Kowalski
Summer River Water Temperature Changes In The Musconetcong River And Their Potential Impact On Aquatic Habitat, Joseph Anthony Kowalski
Theses, Dissertations and Culminating Projects
Water temperature changes in rivers can happen quickly for multiple reasons, and can drastically impact the river in many ways. The potential for temperature shifts to impact rivers is especially important in the summer, for aquatic habitats, as the warm temperatures can stress populations. This is especially true for trout populations, a temperature-sensitive fish. Since temperature is the most important factor in the growth of trout, these temperature changes can be life threatening. Therefore it is important to monitor temperatures in the Musconetcong River, classified as trout maintenance waters (Musconetcong Advisory Committee et al., 2003), because of the potential negative …
Organic Geochemical Investigations Of Urban Sediments By Pyrolysis-Gas Chromatography / Mass Spectroscopy, Kevin Olsen
Organic Geochemical Investigations Of Urban Sediments By Pyrolysis-Gas Chromatography / Mass Spectroscopy, Kevin Olsen
Theses, Dissertations and Culminating Projects
Pyrolysis-Gas Chromatography / Mass Spectrometry (Py-GC/MS) can be used to study the organic matter in sedimentary environments.
An urban sediment is not simply defined by proximity to a city. Because cities have anthropogenic contamination, one important urban sediment characteristic is ongoing recontamination. Another is legacy contamination from industrial activity and a third is the alteration of natural bio-geochemical systems.
Two case studies are presented. The surface sediments of the Gateway National Recreation Area were sampled during the summer of 2007. The ratio of two pyrolysis products, Vinylguiacol, from terrestrial plant lignins, and Indole, from proteins, (VGI Index) is moderately well …
Plant-Microbial Interactions Change Along A Prairie Restoration Chronosequence, Anna Herzberger
Plant-Microbial Interactions Change Along A Prairie Restoration Chronosequence, Anna Herzberger
Undergraduate Honors Theses
Soil microbial communities are critical in determining the performance and density of species in plant communities. However, their role in regulating the success of restorations is much less clear. This study assessed the ability of soil microbial communities to regulate the growth and performance of two potentially dominant grasses and two common forbs in prairie restorations. Specifically, I examined the effects of soil microbial communities along a restoration chronosequence from agricultural fields to remnant prairies using experimentally inoculated soils. The two grass species, Andropogon gerardii and Sorghastrum nutans, produced larger biomass with the agricultural inoculates and experienced a decline …
Estimating Nitrogen Fixation Rates, Importance, And Short-Term Efficiency In Small, Temperate Reservoirs Using Delta15n Techniques, Bryant Christopher Baker
Estimating Nitrogen Fixation Rates, Importance, And Short-Term Efficiency In Small, Temperate Reservoirs Using Delta15n Techniques, Bryant Christopher Baker
Graduate Theses and Dissertations
Nitrogen (N2) fixation can give certain species of cyanobacteria a competitive advantage in lake and reservoir phytoplankton. These species of cyanobacteria, along with others that cannot fix N2, can form toxic compounds that impair water quality when present in high concentrations. N2 fixation rates may be substantial in small (< 1.0 km2), temperate reservoirs since these systems experience thermal stratification and often nitrogen (N) limitation throughout a substantial proportion of the year. However, the effects of N2 fixation on N cycling, alleviation of short-term N limitation, and water quality are not well-understood. A mesocosm experiment and ecosystem-scale observational study were conducted to 1) determine the efficiency of N2 fixation under varying N relative to phosphorus (P) supply, 2) examine the effects of N2 fixation on autotrophic biomass accumulation and microcystin production, and 3) measure N2 fixation rates and importance to autotrophic N demand and zooplankton N assimilation. Results of the mesocosm experiment indicated that N2 fixation was increased at low N:P supply under high P. However, N2 fixation was inefficient at alleviating N limitation when fixed N was the primary source of N. Additionally, microcystin production occurred only at high N:P supply when N2 fixation was low, indicating that reducing external N inputs may have a positive effect on water quality. Results of whole-reservoir determination of N2 fixation using seston δ15N natural abundances indicated that N2 fixation rates throughout the warm season were substantial and influenced by water temperature. Annual N2 fixation rates ranged from 2.2 - 6.6 g N m-2 yr-1, and contributed up to 19% of the annual autotrophic N demand. Zooplankton were assimilating fixed N in most of the study reservoirs, representing a possible mechanism of ecosystem fixed N retention. Collectively, these results suggest that N2 fixation plays a substantial role in N cycling in small, temperate reservoirs, but likely cannot alleviate short-term N limitation.
Fertilizer Nitrogen Uptake Efficiency In Soft Red Winter Wheat And The Ability Of N-Star To Detect Alkaline Hydrolyzable Nitrogen In Crop Residues, Lana Aubrey Clark
Fertilizer Nitrogen Uptake Efficiency In Soft Red Winter Wheat And The Ability Of N-Star To Detect Alkaline Hydrolyzable Nitrogen In Crop Residues, Lana Aubrey Clark
Graduate Theses and Dissertations
Soil testing methods such as the Illinois Soil Nitrogen Test (ISNT) and Direct Steam Distillation (DSD) have been developed which measure alkaline hydrolyzable-N (AH-N) as a means of estimating potentially mineralizable-N. Crop residues play an important role in N cycling. However, the ability of the ISNT and DSD methods to determine AH-N within crop residues is unknown. Therefore, the first objective of this study was to determine the ability of the ISNT and DSD to quantify potentially mineralizable-N within five different crop residues common to Arkansas. Corn (Zea mays L.), soybean (Glycine max, L.), wheat, rice (Oryza sativa, L.), and …
Understanding Selenium Distribution In Lake Mead Using A Three-Dimensional Hydrodynamic Based Water Quality Model, Xiaolu Wei
UNLV Theses, Dissertations, Professional Papers, and Capstones
Shallow groundwater and surface drainages in Las Vegas Wash are known to have elevated level of selenium which mainly comes from the naturally occurring geological hotspots on the southeast side of the Las Vegas Valley. Selenium fate and transport after it enters into Lake Mead from the Las Vegas Wash are not clearly understood. An open sourced three-dimensional Environmental Fluid Dynamic Code model (EFDC), developed by the United States Environmental Protection Agency, was used to model movement of selenium in the Boulder Basin, Lake Mead. The model was calibrated by observed data from 2006 to 2007. The concept of Lagrangian …
Restoration Of Tryptophan Hydroxylase Functions And Serotonin Content In The Atlantic Croaker Hypothalamus By Antioxidant Treatment During Hypoxic Stress, Md. Saydur Rahman, Peter Thomas
Restoration Of Tryptophan Hydroxylase Functions And Serotonin Content In The Atlantic Croaker Hypothalamus By Antioxidant Treatment During Hypoxic Stress, Md. Saydur Rahman, Peter Thomas
School of Earth, Environmental, & Marine Sciences Faculty Publications
Antioxidants are prototypical scavengers of oxygen-free radicals and have been shown to prevent neuroendocrine dysfunction in vertebrates during oxidative stress. In the present study, we investigated whether antioxidant treatment can reverse hypoxia-induced down-regulation of hypothalamic tryptophan hydroxylase (TPH) and serotonergic functions in Atlantic croaker. Hypothalamic neuronal contents of TPH-1 and TPH-2 proteins, serotonin (5-hydroxytryptamine, 5-HT) and its precursor, 5-hydroxytryptophan (5-HTP) as well as hypothalamic TPH-1 and TPH-2 mRNA expression and TPH activity were measured in croaker after exposure to hypoxia and treatment with pharmacological agents. Multiple injections of N-ethylmaleimide, a sulfhydryl alkylating agent, caused comparable decreases in hypothalamic TPHs functions …
Spreading The Char: The Importance Of Local Compatibility In The Diffusion Of Biochar Systems To The Smallholder Agriculture Community Context, Laura C. V. Munoz
Spreading The Char: The Importance Of Local Compatibility In The Diffusion Of Biochar Systems To The Smallholder Agriculture Community Context, Laura C. V. Munoz
Pomona Senior Theses
This thesis enters the context of smallholder agriculture communities in the developing world. It explores the potentials of biochar and what biochar systems could bring to the smallholder communities while simultaneously bringing environmental benefits. It then acknowledges the challenges of diffusion –the spreading of an unfamiliar innovation. It seeks to answer the question of what will make diffusion of biochar systems more successful in the smallholder context, fixating on the characteristic of compatibility as well as the role local community members can play in making a new biochar system more visible to the rest of the communities.
Three-Dimensional Reconstruction Of Marine Clay Nano- And Microstructure By Transmission Electron Microscopy: Analysis Of Fabric And Pore Network, Jessica Rae Gardner Douglas
Three-Dimensional Reconstruction Of Marine Clay Nano- And Microstructure By Transmission Electron Microscopy: Analysis Of Fabric And Pore Network, Jessica Rae Gardner Douglas
Master's Theses
Three-dimensional reconstructions of marine fine-grained sediment open a new dimension for studying nano- and microscale organo-clay fabric important to improving and advancing organic matter (OM) sequestration and fluid flow dynamics modeling. I created 3-D reconstructions of clay fabric and pore pathways from serial sections and photographic mosaics obtained using transmission electron microscopy. These reconstructions show aggregations of clay domains, surrounding OM, and pore networks. I examined a Model sample (laboratory consolidated) with 1% OM and a Natural sample (polychaete fecal pellet) with high levels of OM. Three-dimensional reconstructions were segmented into 300 nm cube subsamples to make highly localized qualitative …
Effects Of Instrumentation On Dental Microwear Textures: Reanalysis And Augmentation Of An Early Hominin Sample, Anna Jacquelyn Ragni
Effects Of Instrumentation On Dental Microwear Textures: Reanalysis And Augmentation Of An Early Hominin Sample, Anna Jacquelyn Ragni
Graduate Theses and Dissertations
Dental microwear texture analysis has been refined to a methodology relying upon scanning confocal microscopy for its advantages of repeatability and standardized quantification. A new instrument, the Plu Neox (Sensofar Corp.) confocal profiler recently entered the market, sparking questions among dental anthropologists related to the advantages and efficacy of this new technology, which has better resolution and lighting properties than previously available white-lighted based confocal profilers. This thesis reports on three complementary studies that set out to evaluate the comparability of the Plu Neox to the Plu Standard system and assess its ability to distinguish primates on the basis of …
Late Pleistocene And Holocene Bison Of Grand Canyon And Colorado Plateau: Implications From The Use Of Paleobiology For Natural Resource Management Policy, Jeffrey M. Martin
Late Pleistocene And Holocene Bison Of Grand Canyon And Colorado Plateau: Implications From The Use Of Paleobiology For Natural Resource Management Policy, Jeffrey M. Martin
Electronic Theses and Dissertations
Bison spp. (bison) fossils are scarce on the Colorado Plateau, especially within the greater Grand Canyon region. Because of the poor fossil record for bison on the plateau and in Grand Canyon National Park, various resource managers have surreptitiously designated bison a nonnative and human-introduced species. The lack of evidence for bison seems to be the result of collection bias rather than a true lack of bison remains. Today, Grand Canyon National Park has a neighboring herd of 350 bison that have meandered unwantedly onto National Park lands from neighboring Forest Service and State of Arizona lands. This study spatiotemporally …
Changes In The Discharge Characteristics Of The Hudson River, Elen Kenny Teo
Changes In The Discharge Characteristics Of The Hudson River, Elen Kenny Teo
Theses, Dissertations and Culminating Projects
The Hudson River watershed has undergone significant urbanization in some areas and reforestation in others during the past century. The watershed has also recently experienced extreme flood events, including from Hurricane Irene, which caused 49 deaths and an estimated $15.8 billion in damage nationally. However, it is unclear how much changes in land use and/or climate have caused shifts in river discharge and the contributions of runoff and baseflow to the river. Determining the existence and magnitude of these shifts are important for managing water resources. This study analyzes changes in daily flows and maximum annual discharge events at multiple …