Digital Commons Network^™

No Major Changes On Paleoclimate And Paleoenvironment Across The Eocene–Oligocene Transition In The Central Rocky Mountains, Sara Ayyash

Earth & Environmental Sciences Theses - Archive

Earth’s climate has experienced dramatic cooling during the Eocene-Oligocene Transition (EOT) based on well-constrained marine geological records, however, a consensus on the terrestrial responses to this event has not been reached. The White River Formation in the central Rocky Mountains, western U.S.A., is a well-dated stratigraphic unit covering the EOT. The formation contains tuffaceous mudrock and sandstone that were deposited in fluvial and eolian depositional environments. Here I study oxygen isotope ratios and clumped isotope temperatures of carbonate cements and bulk organic carbon isotope ratios in order to reconstruct the paleoenvironment and paleoclimate across the EOT. These carbonate cements were …

The Volta Grande Do Xingu: Reconstruction Of Past Environments And Forecasting Of Future Scenarios Of A Unique Amazonian Fluvial Landscape, A. O. Sawakuchi, G. A. Hartmann, H. O. Sawakuchi, F. N. Pupim, D. J. Bertassoli, M. Parra, J. L. Antinao, L. M. Sousa, M. H. Sabaj Pérez, P. E. Oliveira, R. A. Santos, J. F. Savian, C. H. Grohmann, V. B. Medeiros, Michael M. Mcglue, D. C. Bicudo, S. B. Faustino

Earth and Environmental Sciences Faculty Publications

The Xingu River is a large clearwater river in eastern Amazonia and its downstream sector, known as the Volta Grande do Xingu (“Xingu Great Bend”), is a unique fluvial landscape that plays an important role in the biodiversity, biogeochemistry and prehistoric and historic peopling of Amazonia. The sedimentary dynamics of the Xingu River in the Volta Grande and its downstream sector will be shifted in the next few years due to the construction of dams associated with the Belo Monte hydropower project. Impacts on river biodiversity and carbon cycling are anticipated, especially due to likely changes in sedimentation and riverbed …

Understanding The Impact Of Intensive Horticulture Land-Use Practices On Surface Water Quality In Central Kenya, Faith K. Muriithi, Danlin Yu

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Rapid expansion of commercial horticulture production and related activities contribute to declining surface water quality. The study sought to understand the impacts on select rivers in Laikipia and Meru, production hotspots. The specific aims were (1) to identify prevailing surface water quality by examining variations of 14 physico-chemical parameters, and (2) to categorize measured surface water quality parameters into land use types highlighting potential pollutant source processes. Water samples were collected in July and August 2013 along 14 rivers in the study area. The data were analyzed using principal component analysis (PCA) and discriminant analysis (DA). Principal components (PCs) explained …

The Geotraces Intermediate Data Product 2014, The Geotraces Group, Tim M. Conway

School of Geosciences Faculty and Staff Publications

The GEOTRACES Intermediate Data Product 2014 (IDP2014) is the first publicly available data product of the international GEOTRACES programme, and contains data measured and quality controlled before the end of 2013. It consists of two parts: (1) a compilation of digital data for more than 200 trace elements and isotopes (TEIs) as well as classical hydrographic parameters, and (2) the eGEOTRACES Electronic Atlas providing a strongly inter-linked on-line atlas including more than 300 section plots and 90 animated 3D scenes. The IDP2014 covers the Atlantic, Arctic, and Indian oceans, exhibiting highest data density in the Atlantic. The TEI data in …

Depositional Facies And Sequence Stratigraphy Of Niagaran-Lower Salina Reef Complex Reservoirs Of The Guelph Formation, Michigan Basin, Matthew J. Rine

Masters Theses

Hydrocarbon reservoirs in the Niagara-Lower Salina Reef Complex in the Michigan Basin have been extensively studied since the early 1960’s. These reservoirs host an immense hydrocarbon resource, existing as closely-spaced, highly-compartmentalized reservoirs that have produced >500 million barrels of oil and 2.9 trillion cubic feet of natural gas. Previous studies depict these “pinnacle reefs” as tall, symmetrical towers with a random distribution of facies. This study utilizes abundant core data (32 cores, 20-acre spacing), thin-section petrography, and petrophysical wire-line logs to reconstruct the geometry, facies distributions, depositional history, and sequence stratigraphy of the Columbus III Reef Complex within the Southern …

The Effect Of Warming And Simulated Rainfall On Soil Microbial Community Structure And Function, Torri A. Ivancic

Biology Theses

Soil respiration, from plant roots and soil microbes, accounts for 60 – 80 percent of total ecosystem respiration, with the microbial component contributing approximately 54 percent. Global climate trends resulting from CO₂ emissions include increased soil temperatures and changes in precipitation regimes resulting in less frequent, more intense rainfall events. Soil temperature and moisture availability drive soil respiration rates, but how they impact the microbial respiration is poorly qualified. I investigated how the soil microbial community responds to changes in temperature and moisture availability in a laboratory based experiment. Soils from a mixed hardwood forest under two thermal regimes …

Fire And Flood Expand The Floodplain Shifting Habitat Mosaic Concept, W. J. Kleindl, Mark C. Rains, L. A. Marshall, F. R. Hauer

School of Geosciences Faculty and Staff Publications

The floodplain shifting habitat mosaic concept suggests that habitat patch dynamics are influenced by hydrologic disturbances driven by flood pulses of sufficient power to initiate incipient motion of the substratum and maintain cut-and-fill alluviation of the channel and banks. However, floodplain habitat mosaics are subject to other important landscape-scale disturbance regimes. In the Rocky Mountains of the USA and Canada, fire also affects floodplain habitat patch composition. The floodplain exists at the intersection of disturbance regimes that shape the riverscape and those that shape the landscape. We extended the shifting habitat mosaic concept by examining the effects of multiple disturbance …

Thermodynamic Modeling Of Aqueous Geochemistry Of Chlorine Salts: Application To Stability And Habitability Of Liquid Brines On Mars, Amira Elsenousy

Graduate Theses and Dissertations

The WCL (Wet Chemistry Lab) instrument on board the Mars’s Phoenix Lander has identified the soluble ionic composition of the soil at the landing site. Two important ions were detected at the landing site; perchlorates (ClO4-) with a concentration of ~ 2.4 wt% and chlorides (Cl-) with a concentration of 0.54 wt%. Between chloride and perchlorate ions three other oxidized ions exist and called chlorine ions: hypochlorite ClO - (ox. state +1), chlorite ClO2- (ox. state +3) and chlorate ClO3- (ox. state +5). These oxidized ions might be existed as intermediate species on the surface of Mars but remained undetected. …

Defining The Potassium Nutritional Requirements And Distribution Among Plant Parts Of Representative Soybean Cultivars From Different Maturity Groups, Md. Rasel Parvej

Graduate Theses and Dissertations

The potassium (K) requirement of soybean [Glycine max (L.) Merr.] was investigated to determine whether cultivar sensitivity to K deficiency was affected by growth habit (determinate or indeterminate) and how cultivars from each growth habit accumulate and distribute K among plant structures. We also diagnosed K deficiency across reproductive growth stages (R2-6) using trifoliolate leaf- and petiole-K concentrations and at harvest (R8) using seed-K concentration. Soybean responded similarly to K deficiency in terms of yield, selected yield components, and seed-K concentration, regardless of growth habit. The yield loss from K deficiency was greatest on the middle to upper nodes of …

Validation Of Soil-Test-Based Phosphorus And Potassium Fertilizer Recommendations For Rice And Soybean, Matthew Scott Fryer

Graduate Theses and Dissertations

The science of soil-testing for nutrient management and fertilizer recommendations is widely accepted among scientists and agronomists. Although this science is unsurpassed in predicting soil nutrient availability, soil-test interpretations are seldom validated. Major research objectives for irrigated soybean [Glycine max (L.) Merr.] and direct-seeded, delayed-flood rice (Oryza sativa L.) were to: i) validate the accuracy of Mehlich-3 soil-test P (STP) and K (STK) interpretations and ii) published critical tissue-P and -K interpretations in predicting the yield response to fertilizer at different significance levels (p≤0.05 to 0.25), iii) examine how seed nutrient concentrations are influenced by fertilization and crop response to …

Hydrology-Biology Response Relationships In The Ozark Highlands, Dustin Thomas Lynch

Graduate Theses and Dissertations

I examined flow-ecology relationships among stream communities in the Ozark Highlands, USA. I sampled fish, crayfish, and benthic macroinvertebrates during two consecutive summers, including a drought year (2012) and a flood year (2013). Biological response variables related to community structure were assessed via two different statistical methods: an Information Theoretic approach relating response variables to a priori selected predictor variables incorporating hydrology, habitat, geomorphology, and water quality, and canonical ordination using forward selection to relate these same response variables to a large assortment of hydrologic metrics. In addition to assessing metrics related to predicted natural flow, flow alteration at gaged …

Ediacaran Ocean Redox Evolution, Swapan Kumar Sahoo

UNLV Theses, Dissertations, Professional Papers, and Capstones

The relative role that environmental versus intrinsic biological factors played in

shaping the history of life on Earth is a fundamental but unanswered question in the

natural sciences. Most famously, it has been heavily debated if the emergence and

diversification of early animals during the Ediacaran Period (ca. 635–541 Ma) was tied to

a rise in atmospheric-oceanic oxygen levels. Temporally discontinuous geochemical data and patchy fossil record in literature are inadequate to chart the Ediacaran redox history and its causal relationship with the biotic evolution. My PhD study aims for a multiproxy geochemical record within a well-established stratigraphic framework of …

Soft-Sediment Deformation And Dune Collapse In The Navajo Sandstone, Colby Ford

Loma Linda University Electronic Theses, Dissertations & Projects

The Canyon Overlook Trail of Zion National Park follows an outcrop of Navajo Sandstone, which displays a uniquely well-exposed assemblage of features associated with failure of the lee face of a large eolian dune, and run-out over an expanse of interdune sediments downwind of that bedform. Exposed features include dramatic folds in the interdune succession and a stacked series of thrust sheets incorporating both interdune and overlying dune deposits. Thrust surfaces display consistent strikes, parallel to those of undeformed foresets, and incorporate zones of brittle failure and fluid deformation, including folds overturned in the direction of foreset dip. These features …

High-Resolution Correlation Of A Time-Bounded Unit Of The Pisco Formation, Peru, Daniel J. O'Hare

Loma Linda University Electronic Theses, Dissertations & Projects

Correlation of beds in the Pisco Basin across significant distances is problematic and has not yet been effectively achieved. I chose to examine an interval bounded by two time markers, an 40Ar/39Ar-dated white tuff at the base and an 40Ar/39Ar-dated tuff couplet at the top. This interval was chosen because of the continuity and excellent exposure of the tuff beds at six distinct locations in a linear transect 30 km long. Correlation of units was achieved through 40Ar/39Ar dating, lithology, sedimentary structures, and magnetic susceptibility. The vertical and lateral variability in lithology, fossil assemblages, structures, and sequences was examined in …

Identities And Motives Of Naturalist Development Program Attendees And Their Relation To Professional Careers, Jennifer A. Mraz

Dissertations

In recent years, there has been much concern over the decline of biologists who actually identify themselves to be naturalists, which negatively impacts the field of conservation and the study of biology as a whole. This could result in a decrease in individuals who participate in naturalist-like activities, such as informal environmental education and environmental volunteerism. The purpose of my study was to determine what discourse identities were held by naturalist development program participants, how these discourse identities related to their volunteer motives in environmental settings, and how discourse identity related to professional careers. I defined identity through the lens …

Decomposition And Nitrogen Dynamics Of Turtle Grass (Thalassia Testudinum) In A Subtropical Estuarine System, Monica Delgado

Theses and Dissertations

Seagrass beds are pivotal in the functioning of coastal ecosystems in terms of productivity, organic matter turnover and nutrient cycling. Aiming to document decay and nitrogen (N) dynamics of turtle grass (Thalassia testudinum) in a subtropical estuarine system, decomposition patterns of leaves and rhizomes were characterized and compared. Nitrogen usage during decomposition of tissues, and of live tissues and epiphytes growing on live leaves, was also quantified and compared. Stable isotope ratios allowed tracing N within the seagrass bed, following N incorporation into seagrass tissues from the surrounding media (water, sediment). Leaves had a higher N content and decomposed at …

Exploring, Exploiting And Evolving Diversity Of Aquatic Ecosystem Models: A Community Perspective, Annette B.G. Janssen, George B. Arhonditsis, Arthur Beusen, Karsten Bolding, Louise Bruce, Jorn Bruggeman, Raoul-Marie Couture, Andrea S. Downing, J. Alex Elliott, Marieke A. Frassl, Gideon Gal, Daan J. Gerla, Matthew R. Hipsey, Fenjuan Hu, Stephen C. Ives, Jan H. Janse, Erik Jeppesen, Klaus D. Jöhnk, David Kneis, Xiangzhen Kong, Jan J. Kuiper, Moritz K. Lehmann, Carsten Lemmen, Deniz Özkundakci, Thomas Petzoldt, Karsten Rinke, Barbara J. Robson, René Sachse, Sebastiaan A. Schep, Martin Schmid, Huub Scholten, Sven Teurlincx, Dennis Trolle, Tineke A. Troost, Anne A. Van Dam, Luuk P.A. Van Gerven, Mariska Weijerman, Scott A. Wells, Wolf M. Mooij

Civil and Environmental Engineering Faculty Publications and Presentations

Here, we present a community perspective on how to explore, exploit and evolve the diversity in aquatic ecosystem models. These models play an important role in understanding the functioning of aquatic ecosystems, filling in observation gaps and developing effective strategies for water quality management. In this spirit, numerous models have been developed since the 1970s. We set off to explore model diversity by making an inventory among 42 aquatic ecosystem modellers, by categorizing the resulting set of models and by analysing them for diversity. We then focus on how to exploit model diversity by comparing and combining different aspects of …

Using Foraminifera Shell Geochemistry To Test Proxies For Paleoenvironmental Reconstruction, Catherine Hudson

Honors Capstones

No abstract provided.

Glass Shards At Pinnacle Point Rock Shelter 5-~6, South Africa: Are They From The Last Super-~Eruption Of Toba?, Amber Elizabeth Ciravolo

UNLV Theses, Dissertations, Professional Papers, and Capstones

Cryptotephra, in the form of individual glass shards, have been discovered in paleoarchaeological site PP5-6 North at Pinnacle Point, Western Cape, South Africa. This marks the first documentation of cryptotephra in a South African paleoarchaeological site. PP5-6 North is a rock shelter in the cliffs along the coast of the Western Cape and is one of a series of caves and rock shelters at Pinnacle Point that were inhabited by early modern humans. The presence of cryptotephra at PP5-6 is an important discovery in terms of tephra preservation in cave deposits as well as the possibility of tephra being present …

Available Nitrogen And Denitrification In Soil Altered By Ground Cover And Nutrient Source In An Organic Apple Orchard, Jade Nicole Ford

Graduate Theses and Dissertations

A shift in public demand towards more organic and locally produced fruit and vegetables has been occurring across the United States in recent years. A common practice in organic fruit production is the application of organic ground covers to supply nutrients while enhancing other soil properties. A need for research exists in the southern region of the U.S. examining the effects of regionally applicable ground cover and nutrient management on nitrogen availability and the microbial community to provide information to organic farmers in the region. Two studies were conducted to determine how 12 treatment combinations of four ground covers (compost, …

Convergence Of Microbial Assimilations Of Soil Carbon, Nitrogen, Phosphorus And Sulfur In Terrestrial Ecosystems, Xiaofeng Xu, Dafeng Hui, Anthony W. King, Xia Song, Peter E. Thornton, Lihua Zhang

Biology Faculty Research

How soil microbes assimilate carbon-C, nitrogen-N, phosphorus-P and sulfur-S is fundamental for understanding nutrient cycling in terrestrial ecosystems. We compiled a global database of C, N, P and S concentrations in soils and microbes and developed relationships between them by using a power function model. The C:N:P:S was estimated to be 287:17:1:0.8 for soils and 42:6:1:0.4 for microbes. We found a convergence of the relationships between elements in soils and in soil microbial biomass across C, N, P and S. The element concentrations in soil microbial biomass follow a homeostatic regulation curve with soil element concentrations across C, N, P …

Mercury In Coniferous And Deciduous Upland Forests In Northern New England, Usa: Implications Of Climate Change, J. B. Richardson, A. J. Friedland

Dartmouth Scholarship

Climatic changes in the northeastern US are expected to cause coniferous stands to transition to deciduous stands over the next hundred years. Mercury (Hg) sequestration in forest soils may change as a result. In order to understand potential effects of such a transition, we studied aboveground vegetation and soils at paired coniferous and deciduous stands on eight mountains in Vermont and New Hampshire, USA.

A Comparative Analysis Of Portable X-Ray Fluorescence Spectrometry And Stable Isotopes In Assessing Ancient Coastal Peruvian Diets, Theresa Jane Gilbertson

USF Tampa Graduate Theses and Dissertations

This dissertation explores a cross-cultural analysis of the dietary signatures of four coastal cultures of prehistoric Peru. A combination of elemental analysis based on portable x-ray fluorescence spectrometry (pXRF), testing trace elements presented in 209 individuals’ skulls representing the Nazca (38), Cañete (33), Lima (40), and Moche (98) valleys and/or cultures of the first millennium AD, is weighed in conjunction with isotope ratio mass spectrometry (IRMS) to analyze human bone collagen and bone apatite derived from a portion of the individuals represented in the Nazca, Cañete, and Lima cranial samples.

Evidence from the results of both tests are weighed using …

Phosphorus Sorption Dynamics In Shallow Groundwater, Coastal Everglades, Florida, Usa, Hilary Flower

USF Tampa Graduate Theses and Dissertations

For this dissertation I studied phosphorus (P) sorption dynamics in the shallow groundwater of the southern Everglades. In particular, I examined how the ambient water type governs soluble reactive P (SRP) availability through adsorption/desorption reactions with the aquifer matrix. Chapter 2 investigated how P sorption dynamics of the mangrove root zone sediment are affected by high bicarbonate brackish groundwater compared to both fresh groundwater and saltwater. The results from chapter 2 show that the sediment exhibited exceptionally low sorption efficiency in the high bicarbonate brackish water, which would allow ambient water SRP concentration to be maintained at a higher level. …

Understanding Acceptable Level Of Risk: Incorporating The Economic Cost Of Under-Managing Invasive Species, Alisha D. Davidson, Chad L. Hewitt, Donna R. Kashian

Environmental Science and Geology Faculty Research Publications

Management of nonindigenous species includes prevention, early detection and rapid response and control. Early detection and rapid response depend on prioritizing and monitoring sites at risk for arrival or secondary spread of nonindigenous species. Such monitoring efforts require sufficient biosecurity budgets to be effective and meet management or policy directives for reduced risk of introduction. Such consideration of risk reduction is rarely considered, however. Here, we review the concepts of acceptable level of risk (ALOR) and associated costs with respect to nonindigenous species and present a framework for aligning risk reduction priorities with available biosecurity resources. We conclude that available …

In Situ Studies Of Limestone Dissolution In A Coastal Submarine Spring, Rachel Marie Schweers

USF Tampa Graduate Theses and Dissertations

Limestone dissolution in karst environments is likely due to geochemistry of the water, the actions of microbial communities, and the effect of water flow. We explored the rate of limestone dissolution and will examine here the microbial communities associated with the limestone. A conduit within the brackish cave, Double Keyhole Spring, on the coast of central west Florida was the site of the experiment. PVC pipes (5cm x 16cm) were filled with crushed limestone that was screened to a 1.9cm – 2.54cm size range. There were three treatments (5 replicates each): Control - sealed autoclaved controls with limestone and conduit …

Flow And Scour Constrainst On Uprooting Of Pioneer Woody Seedlings, Sharon Bywater-Reyes, Andrew C. Wilcox, John C. Stella, Anne Lightbody

Geosciences Faculty Publications

Scour and uprooting during flood events is a major disturbance agent that affects plant mortality rates and subsequent vegetation composition and density, setting the trajectory of physical-biological interactions in rivers. During flood events, riparian plants may be uprooted if they are subjected to hydraulic drag forces greater than their resisting force. We measured the resisting force of woody seedlings established on river bars with in situ lateral pull tests that simulated flood flows with and without substrate scour. We quantified the influence of seedling sizes, species (Populus and Tamarix), water-table depth, and scour depth on resisting force. Seedling …

Ua24 Mcicsl Newsletter - November 2015, Shannon R. Trimboli Education Coordinator

MCICSL Newsletter

This issue includes the following:

Partners Recognized for Water Quality Research at Mammoth Cave National Park and Increasing Diversity in the Geosciences

Texas A&M – Galveston Students Participate in Citizen Science at Mammoth Cave National Park

Northern Kentucky University and the Mammoth Cave International Center for Science and Learning to Host Partners in the Parks Program at Mammoth Cave National Park

as well as education and research highlights, and MCICSL symposium information

3d Geometric Morphometrics In Modern And Extinct Foot-Propelled Diving Birds: An Evaluation Of The Tarsometatarsus For Species Identification, Mackenzie E. Kirchner-Smith

Master's Theses or Doctor of Nursing Practice

Hesperornithiformes (Aves: Ornithurae) were flightless foot-propelled diving birds that lived during the Late Cretaceous and have a good fossil record compared to most Mesozoic birds. Extinct taxa are often identified using fragmentary or isolated specimens, and several species of Hesperornis have been named from the morphology of the tarsometatarsus, often relying on size for taxonomic differentiation. However, little has been done to examine intraspecific variation in this bone and evaluate its use for taxonomic identification. To test for intraspecific and interspecific variation in the tarsometatarsus of hesperornithiforms, variation in extant members of the foot-propelled diving Gaviidae (loons) and Podicipedidae (grebes) …

8000 Years Of Environmental Evolution Of Barrier–Lagoon Systems Emplaced In Coastal Embayments (Nw Iberia), Rita González-Villanueva, Marta Pérez-Arlucea, Susana Costas, Roberto Bao, Xose L. Otero, Ronald J. Goble

Department of Earth and Atmospheric Sciences: Faculty Publications

The rocky and indented coast of NW Iberia is characterized by the presence of highly valuable and vulnerable, small and shallow barrier– lagoon systems structurally controlled. The case study was selected to analyse barrier–lagoon evolution based on detailed sedimentary architecture, chronology, geochemical and biological proxies. The main objective is to test the hypothesis of structural control and the significance at regional scale of any highenergy event recorded. This work is also aimed at identifying general patterns and conceptualizing the formation and evolution of this type of coastal systems. The results allowed us to establish a conceptual model of Holocene evolution …