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Continental Warming Preceding The Paleocene–Eocene Thermal Maximum, Ross Secord, Philip D. Gingerich, Kyger C. Lohmann, Kenneth G. Macleod

Department of Earth and Atmospheric Sciences: Faculty Publications

Marine and continental records show an abrupt negative shift in carbon isotope values at ~55.8 Myr ago. This carbon isotope excursion (CIE) is consistent with the release of a massive amount of isotopically light carbon into the atmosphere and was associated with a dramatic rise in global temperatures termed the Paleocene–Eocene thermal maximum (PETM). Greenhouse gases released during the CIE, probably including methane, have often been considered the main cause of PETM warming. However, some evidence from the marine record suggests that warming directly preceded the CIE, raising the possibility that the CIE and PETM may have been linked to …

Hrc Enews — 2010 Fall, Megan K. Svarz

Publications (HRC)

This issue contains staff accomplishments and announcements, event listings, and a "new faces" listing for new staff, affiliates, and researchers.

Development Of Agroecology Based Garden System And Educational Program At Grand Valley State University, Kendall Gilbert, Edwin Joseph

Student Summer Scholars Manuscripts

This study was part of a twelve- week project to introduce agroecology growing principles and educational models at the Community Garden on the campus of Grand Valley State University in Allendale, Michigan. This project was set up to be a demonstration for the further development of the garden space as an area for agroecology focused education, extension, and outreach. To accomplish this, three areas of change became essential components to developing a garden space that can serve as a living laboratory, demonstration area, and outdoor classroom. The first project goal was to develop and create a demonstration garden plot that …

Comparison Of Ice Core Dissolved Organic Matter From A Greenland Ice Core By Nanospray Fourier Transform Ion Cyclotron Resonance Mass Spectrometry, Joshua Jeremiah Shiloh Marsh

Chemistry & Biochemistry Theses & Dissertations

Recent studies of ice cores have embarked on the task of determining the classes of dissolved organic matter (DOM) present in melt-water from the cores collected in numerous locations in the northern and southern hemispheres. This DOM originally derives from wet precipitation and is thought to reflect atmospheric organic matter derived from anthropogenic and non-anthropogenic sources. Because the amount of DOM is so low, previous studies have necessarily used large sample volumes (greater than 500 mL) to concentrate sufficient ice core DOM necessary for mass spectral analysis. Solid phase extraction (SPE) with C₁₈ resins was followed by evaporative concentration …

Phosphorus Uptake In Rhodomonas Salina (Wislouch) And Its Effect On Allocation And Elimination In Acartia Tonsa (Dana), Danna Palladino

OES Theses and Dissertations

Phosphorus is a key element in important biochemical compounds, such as RNA and phospholipids, and can become limiting in a variety of marine systems. The uptake of phosphorus into biochemical fractions (protein, low molecular weight (LMW) compounds, lipid, polysaccharide and nucleic acid) in Acartia tonsa fed ³³P -labeled Rhodomonas salina was examined. R. salina was cultured on two variations of one media that in one case contained phosphorus in balance and the other out of balance with relation to other standard f/2 components. The P-balanced (PB) media had a N:P ratio of 24.5, which is higher than that found …

Assessing The Sensitivity Of Water To Surface, Soil, Rock, And Cave Conditions In Fitton Cave, Northern Arkansas, Drew Aaron Westerman

Theses and Dissertations

Fitton Cave, located within the Buffalo National River in north-central Arkansas, offers a window into a relatively pristine portion of the Ozark Plateaus Aquifer. This region is one of the largest karst aquifers in the United States, providing more than 1.8 million people with drinking water. Understanding what happens to water as it moves from the surface to subsurface is requisite for utilization, management, and sustainability of karst aquifers as water resources. As population pressures increase, assessment of geochemical and hydrologic processes from pristine systems such as Fitton Cave will prove invaluable for providing baseline conditions. By integrating vascular plant …

Sensitivity Of Geoelectrical Measurements To The Presence Of Bacteria In Porous Media, Gamal Z. Abdel Aal, Estella A. Atekwana, Silvia Rossbach, D. Dale Werkema

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

We investigated the sensitivity of low-frequency electrical measurements (0.1-1000 Hz) to (1) microbial cell density, (2) live and dead cells, and (3) microbial attachment onto mineral surfaces of clean quartz sands and iron oxide-coated sands. Three strains of Pseudomonas aeruginosa PAO1 (wild type and rhlA and pilA mutant) with different motility and attachment properties were used. Varying concentrations of both live and dead cells of P. aeruginosa wild type in sand columns showed no effect on the real conductivity component (σ′). However, the imaginary conductivity component (σ″) increased linearly with increasing concentrations of live cells in sand columns, whereas minimal …

Virus Silicification Under Simulated Hot Spring Conditions, James R. Laidler, Kenneth M. Stedman

Biology Faculty Publications and Presentations

Silicification of organisms in silica-depositing environments can impact both their ecology and their presence in the fossil record. Although microbes have been silicified under laboratory and environmental conditions, viruses have not. Bacteriophage T4 was successfully silicified under laboratory conditions that closely simulated those found in silica-depositing hot springs. Virus morphology was maintained, and a clear elemental signature of phosphorus was detected by energy-dispersive X-ray spectrophotometry (EDS).

Insights Into Particle Formation And Remineralization Using The Short-Lived Radionuclide, Thorium-234, Kanchan Maiti, Claudia R. Benitez-Nelson, Ken O. Buesseler

Faculty Publications

[1] Simple mass balance models are applied to a high resolution 234Th profile from the northwest Pacific to examine the magnitude, rate, and depth distribution of particle remineralization processes below the euphotic zone (Ez). Here, excess 234Th (234Th > 238U) below the Ez is attributed to fragmentation processes that result in the conversion of sinking to non‐sinking particles. By considering particulate organic carbon (POC) to 234Th ratios on particles, we show that POC flux attenuation is larger than for 234Th, which we attribute to bacterial and zooplankton consumption of sinking POC. Three case studies are used to demonstrate how different combinations …

The Analysis Of Palaeobotanical Remains From Native American Sites In The Tennessee Region Of The Upper Cumberland Plateau., Chase W. Beck

Electronic Theses and Dissertations

Sediment samples were collected from 3 rock shelter sites and one natural pond on the Upper Cumberland Plateau. Samples were processed to quantitatively and qualitatively evaluate pollen and charcoal abundance as well as other palaeobotanicals. The analysis was to determine when prehistoric Native Americans began controlled burns to enhance resources acquisition. Samples were also analyzed for the presence of pollen to determine vegetation changes that may accompany the use of controlled burns and to determine the onset of horticulture. The Upper Cumberland Plateau is often considered a marginal area used only seasonally by Native Americans; however, management practices may have …

Hydrogeomorphic Segments And Hydraulic Microhabitats Of The Niobrara River, Nebraska, With Special Emphasis On The Niobrara National Scenic River, Jason S. Alexander, Ronald B. Zelt, Nathaniel J. Schaepe

United States Geological Survey: Water Reports and Publications

The Niobrara River is an ecologically and economically important resource in Nebraska. The Nebraska Department of Natural Resources’ recent designation of the hydraulically connected surface- and groundwater resources of the Niobrara River Basin as “fully appropriated” has emphasized the importance of understanding linkages between the physical and ecological dynamics of the Niobrara River so it can be sustainably managed. In cooperation with the Nebraska Game and Parks Commission, the United States Geological Survey USGS) investigated the hydrogeomorphic and hydraulic attributes of the Niobrara River in northern Nebraska. This report presents the results of an analysis of hydrogeomorphic segments and hydraulic …

High Pressure Structural Studies On Eus Nano Particles Up To 52 Gpa, Kristie Canaday, Ravhi S. Kumar

Undergraduate Research Opportunities Program (UROP)

Crystal size reduction in bulk materials changes the structural and magnetic properties considerably [1]. More importantly the transition pressure is strongly influenced by temperature, pressure, and the crystallite size effect. Rare earth europium chalcogenides crystallize in the NaCl (rock salt) type structure. The interest in Eu nanomaterials is motivated by the possibility of their use in magnetic devices [2,3]. Recent studies suggest that europium chalcogenide nanocrystals exhibit significant changes in their structural and magnetic properties, compared to bulk chalcogenides, when the nanocrystal diameter decreases. The crystal structure and phase transition behavior of EuS nanoparticles have been investigated and compared as …

Biogeochemical Investigation Of Soda Lake, Kathryn Bywaters, Shaneen Braswell, David Crowther, Bernadette Leonis, Jeremy Memmott, Farrah Moazeni, Christian H. Fritsen

Undergraduate Research Opportunities Program (UROP)

Big Soda Lake, Nevada, is a terminal, volcanic crater lake whose water level is maintained exclusively by groundwater. The crater is composed of volcanic, basaltic sand and the lake is ~60 m deep (Rush, 1972). The lake is meromictic with a distinct chemocline (Kimmel et al. 1978). The chemocline currently rests at ~40 m and is reflected in both specific conductivity and salinity measurements. Below the chemocline a redox gradient develops with highly reducing conditions. The pH is consistent throughout the depth of the lake at ~9.5, proving that it is alkaline in nature. It is further stratified by both …

Temporal And Spatial Variations Of Ions, Isotopes And Agricultural Contaminants In Surface Waters And Groundwater Of Nebraska's Rainwater Basin Wetland Region, Sarah E. Foster

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The wetlands of south-central Nebraska’s Rainwater Basin region are considered of international importance as a habitat for millions of migratory birds, but are being endangered by agricultural practices. The Rainwater Basin extends across 17 counties and covers 4,000 square miles. The purpose of this study was to assemble baseline chemical data for several representative wetlands across the Rainwater Basin region, and determine the use of these chemical data for investigating groundwater recharge.

Eight representative wetlands were chosen across the Rainwater Basin to monitor surface and groundwater chemistry. At each site, a shallow well and deep well were installed and sampled …

Temporal And Spatial Assessment Of Evaporation, Transpiration, And Soil Moisture Redistribution, Brian M. Bird

UNLV Theses, Dissertations, Professional Papers, and Capstones

At a native stand of creosote bush (Larrea tridentata) in North Las Vegas, a rainfall simulation study was conducted over a 12 month period from October 2005 to October 2006. Simulated rainfall occurred during the winter, spring, summer, and fall periods. Rainfall simulation systems were positioned on each of 12 plots, each containing a single creosote bush. Simulated rainfall events occurred at night with multiple short pulses designed to maximize infiltration while minimizing ponding. Yearly simulated rainfall amounts were set at 0, 15, 30 and 60 cm (replicated three times) and were approximately 0, 1.5, 3.0 and 6.0 times the …

Wind Speed Dependence Of Single-Site Wave-Height Retrievals From High-Frequency Radars, Brian K. Haus, Lynn K. Shay, Paul A. Work, George Voulgaris, Rafael J. Ramos, Jorge Martinez-Pedraja

Faculty Publications

Wave-height observations derived from single-site high-frequency (HF) radar backscattered Doppler spectra are generally recognized to be less accurate than overlapping radar techniques but can provide significantly larger sampling regions. The larger available wave-sampling region may have important implications for observing system design. Comparison of HF radar–derived wave heights with acoustic Doppler profiler and buoy data revealed that the scale separation between the Bragg scattering waves and the peak energy-containing waves may contribute to errors in the single-site estimates in light-to-moderate winds. A wave-height correction factor was developed that explicitly considers this scale separation and eliminates the trend of increasing errors …

The Toll Of Toxics: Investigating Environmental Contaminants, Donald Sparling, Barnett A. Rattner, John S. Barclay

United States Geological Survey: Staff Publications

Two recent events [the Deepwater Horizon oil spill and the Asarco settlement] bring to the fore the work of wildlife toxicologists. Focusing on amphibians, reptiles, birds, and mammals, wildlife toxicology is a component of ecotoxicology--the study of toxic effects caused by natural or synthetic pollutants on living organisms and other constituents of ecosystems (Truhaut 1977). Now a distinct discipline within the wildlife profession-practiced by members of The Wildlife Society's own Wildlife Toxicology Working Group, among others-wildlife toxicology has become increasingly important as human populations and industry have spread, causing contaminants to multiply.

Emerging Environmental Contaminants (EECs) include an array of …

Evaluating Efficacy Of Restoration Techniques, Keys View Road Reconstruction, Joshua Tree National Park, California, U.S.A, Scott R. Abella, E. Cayenne Engel

Public Policy and Leadership Faculty Research

Keys View Road in Joshua Tree National Park (JOTR) was recently repaved, resulting in a buffer of vegetation and soil disturbance along the road corridor. In order to mitigate the effects of the repaving, JOTR designed an experimental framework to test various revegetation strategies. They outplanted salvaged and nursery grown native plant species in conjunction with vertical mulch in a fully crossed design (outplanting only, vertical mulch only, outplanting + vertical mulch, bare ground) to examine if any of the treatments most efficiently establish native plant communities.

Tooth Chipping Can Reveal The Diet And Bite Forces Of Fossil Hominins, Paul J. Constantino, James Jin-Wu Lee, Herzl Chai, Bernhard Zipfel, Charles Ziscovici, Brian R. Lawn, Peter W. Lucas

Biological Sciences Faculty Research

Mammalian tooth enamel is often chipped, providing clear evidence for localized contacts with large hard food objects. Here, we apply a simple fracture equation to estimate peak bite forces directly from chip size. Many fossil hominins exhibit antemortem chips on their posterior teeth, indicating their use of high bite forces. The inference that these species must have consumed large hard foods such as seeds is supported by the occurrence of similar chips among known modern-day seed predators such as orangutans and peccaries. The existence of tooth chip signatures also provides a way of identifying the consumption of rarely eaten foods …

The Influence Of Vegetation And Landscape Position On Soil Temperature Change In A Sagebrush-Steppe Eastern Sierra Environment: Implications On Soil Taxonomy, Nathan Michael Lurie

Earth and Soil Sciences

Soil temperature is a parameter that has been studied for a considerable time and from many different perspectives. However, relatively few studies have been conducted for taxonomic purposes and fewer still have focused on how changes in soil temperature related to global climate change may affect soil taxonomy. Soil temperature regimes are used to subdivide soils with similar properties that exist in dissimilar climate zones requiring different management practices depending on intended use. Seven sites with variable surficial features were used for this study within a cohesive sagebrush-steppe Eastern Sierra glacial moraine landform. Soil temperature was measured once a month …

Management And Control Plan For Zinfandel Vines In South Paso Robles, Ca., Tanner E. Campbell

Earth and Soil Sciences

Zinfandel, also known as Zin, is a red skinned variety of wine grape very popular in California. The wines produced from Zinfandel grapes have an intense fruitiness and luscious texture. Production is extremely variable throughout California and is dependent upon, climate, soil fertility, crop level management practices, and irrigation. This study was conducted to determine the on site soil physical and chemical properties as a means to obtain optimal yields and fruit quality. The A & L Western Agriculture Laboratories performed comprehensive fertility analysis to determine the concentrations of the plant essential nutrients, organic matter, electrical conductivity, cation exchange capacity, …

Soil Infiltration Study: Measuring The Difference In Leachate Quality Between Surface Compost Application And Incorporated Compost Application, Christopher Gallo, Kristin Roberts

Earth and Soil Sciences

No abstract provided.

Fragaria Species Grown In A Greenhouse Cropping System Chemigated By Phosfite® And Bacillus® In Subsidence Of Phytophthora Fragariae And Verticillium Dahliae, Russell L. Morgan

Earth and Soil Sciences

Strawberry yields depend directly on infestation of Phytophthora fragariae and Verticillium dahliae in correspondance to the use of Phosfite and Bacillus. The objective is to find understanding of newly administered techniques in prevention of Phytophthora fragariae and Verticillium dahliae and prohibiting the use of Methyl Bromide. Application of Phosfite and Bacillus on patented Fragariae species to identify utilization of P and ZN forms and their aid in prevention of Phytophthora and Verticillium species. In the Plots on the western bench the developmental symptoms of PRR disease were absent within all infested soil containers containing the FHS-1 crop. In the plots …

Structural And Stratigraphic Control On The Migration Of A Contaminant Plume At The P Reactor Area, Savannah River Site, South Carolina, Antonio E. Cameron González, Camelia C. Knapp, Michael G. Waddell, Adrian Addison, John M. Shafer

Faculty Publications

Geophysical methods, including a shallow seismic reflection (SSR) survey, surface and borehole ground-penetrating radar (GPR) data, and electrical resistivity imaging (ERI), were conducted at the Savannah River site (SRS), South Carolina, to investigate the shallow stratigraphy, hydrogeophysical zonation, and the applicability and performance of these geophysical techniques for hydrogeological characterization in contaminant areas. The study site is the P Reactor area located within the upper Atlantic coastal plain, with clastic sediments ranging from Late Cretaceous to Miocene in age. The target of this research was the delineation and prediction of migration pathways of a trichloroethylene (TCE) contaminant plume that originates …

Comparison Of Two Potential Streamgage Locations On Scott Creek At Swanton Pacific Ranch, California, Matthew C. Scrudato

Master's Theses

Two locations on Scott Creek, located 12 miles north of Santa Cruz California, are being considered for the installation of a streamgage to measure discharge. Each location offers unique considerations and challenges in gage construction and discharge measurement capabilities. A detailed flood frequency analysis was completed using a direct watershed comparison, direct equations developed by Waananen and Crippen, a Log Pearson Type III Frequency Distribution, a regional analysis, and two-station comparisons. Final results indicate a 100-year recurrence interval of 6,310 ft3/s at the Upper Scott Creek location and 6,520 ft3/s at the lower location. A detailed indirect measurement revealed that …

Mississippi Canyon 252 Incident Nrda Tier 1 For Deepwater Communities, Gregory Boland, Gary Brewer, Erik Cordes, Amanda Demopoulos, Chuek Fisher, Chris German, Ken Sulak

United States Geological Survey: Staff Publications

The northern Gulf of Mexico (GOM) is geologically diverse basin, described as the most complex continental slope region in the world. Regional topography of the slope consists of basins, knolls, ridges, and mounds derived from the dynamic adjustments of salt and the introduction of large volumes of sediment over long time scales. More than 99% of the sea floor in the GOM consists of soft sediment made up of various mixtures of primarily silt and clay. These wide-spread soft bottom communities are described in reports from major MMS studies by Gallaway et al. (1998) and Rowe and Kennicutt (2009). Relative …

Establishment And Partial Characterization Of A Cell Line From Burbot Lota Lota Maculosa: Susceptibility To Ihnv, Ipnv And Vhsv, Mark P. Polinski, John D. Drennan, William N. Batts, Susan C. Ireland, Kenneth D. Cain

United States Geological Survey: Staff Publications

This study describes the development and partial characterization of a continuous fibroblastic-like cell line (BEF-1) developed from late stage embryos of North American burbot Lota lota maculosa. This cell line has been maintained for over 5 yr and 100 passages in vitro. Cells were cultured using Eagle’s minimum essential medium with Earle’s salts (MEM) supplemented with GlutaMAX ™, and 10% fetal bovine serum (FBS), pH 7.4. The addition of penicillin-streptomycinneomycin (PSN) antibiotic mixture (0.05, 0.05, 0.1 mg ml–1, respectively) did not negatively influence cell replication; however, the antimycotic Fungizone™ (2.5 μg ml–1, amphotericin B) caused cell rounding and …

The Hydro-Ecology Of Everyday Life: Assessing The Social And Environmental Determinants Of Water Use In The Portland Region, Vivek Shandas

Systems Science Friday Noon Seminar Series

Driven in part by the imminent threats of population growth and climate destabilization, recent studies suggest that urban areas face severe water scarcity, with some areas in Australia and the United States already instituting moratoria on water use. While water managers traditionally avoid such crises by developing demand forecasts based on population estimates, technological developments, and weather predictions, their analysis are often at a regional scale with aggregate measures of water consumption. To date, there exists limited empirical evidence about how urban spatial structure and concomitant socio-demographic and temperature characteristics mutually interact to affect water demand at the scale of …

A Re-Evaluation Of The Pleistocene Hellbender, Cryptobranchus Guildayi, And An Overview Of Cryptobranchus Remains From Appalachian Caves., Keila Elaine Bredehoeft

Electronic Theses and Dissertations

Cryptobranchus guildayi is described as an extinct species of large salamander that is closely related to the hellbender, Cryptobranchus alleganiensis. The validity of this extinct taxon has been questioned, so an expanded osteological sample of modern hellbenders was used for comparative purposes with the C. guildayi fossil material. Based on this analysis, all supposed distinguishing morphological characteristics used to define C. guildayi can be observed in specimens of C. alleganiensis, or are based on misidentifications. Therefore, Cryptobranchus guildayi is considered to be conspecific with C. alleganiensis and taxonomically should be considered a junior synonym of the latter. The …

Talus Slope Processes In The Appalachian : An Analysis Of Rock Size And Shape On The Shawangunk Ridge, Northwestern New Jersey, Muhammad Hamidul Haque

Theses, Dissertations and Culminating Projects

Sphericity, hardness, roundness, and size of talus boulders were analyzed to understand the mass wasting process on the Shawangunk Ridge in northwestern New Jersey. Similar studies have been conducted in other localities (e.g., Lassen Peak, California and Spitsbergen, Sweden) but few works were carried out in the eastern United States, particularly in the Appalachian region. During the Pleistocene, ice sheets advanced in North America, and glacial and periglacial (soil and rock affected by ice) environments existed throughout the Appalachians. Although the periglacial climate is not present in this region right now, rock falls are still active where weak joints are …