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Seagrass-Mediated Carbonate Dissolution And Early Diagenesis In Bahamas Bank Sediments, Xinping Hu

OES Theses and Dissertations

This dissertation presents the results of studies examining the role that seagrasses play in carbonate dissolution and early diagenesis of Bahamas Bank sediments. Three aspects of this problem are addressed: (1) stable carbon isotopes as an indicator of early diagenesis of carbonates, using results of a field study; (2) carbonate dissolution stoichiometry and carbonate reprecipitation, using the results from closed-system sediment incubation studies; (3) carbonate dissolution and reprecipitation across the broader Bahamas Bank. In Chapter II, I examined δ¹³C in the dissolved inorganic carbon (DIC) of sediments with various degrees of seagrass densities. In low seagrass density and …

The Observation, Modeling, And Retrieval Of Bio-Optical Properties For Coastal Waters Of The Southern Chesapeake Bay, Xiaoju Pan

OES Theses and Dissertations

The primary purpose of this study was to develop an inverse method to retrieve the inherent optical properties (IOPs) and biogeochemical parameters (e.g. chlorophyll a concentration and salinity) appropriate to monitor the water quality and biogeochemical processes from remote sensing of the coastal waters in the southern Chesapeake Bay and coastal Mid-Atlantic Bight region (MAB) dominated by Case 2 waters. For this purpose, knowledge of the relationship between remote sensing reflectance (R_rs) and IOPs and the effect from bottom reflectance on R_rs, is required.

A substantial investigation of IOPs has been conducted for the coastal …

Effects Of Elevated Atmospheric Co2 On Root Dynamics, Biomass And Architecture In A Scrub-Oak Ecosystem At Kennedy Space Center, Florida, Daniel Benjamin Stover

Biological Sciences Theses & Dissertations

A major gap in whole-plant ecology lies with our understanding of root system growth, function and distribution. Large belowground structures, in addition to fine roots, are of particular interest because of their role in carbon sequestration. Non-destructive methods, including ground-penetrating radar (GPR) and minirhizotron observation tubes, were used to investigate effects of elevated CO₂ on root biomass, dynamics (productivity, mortality, and turnover), root persistence and architecture in a fire dominated scrub-oak ecosystem. Open-top chambers have been exposed to elevated atmospheric CO₂ for the past eleven years at Kennedy Space Center, Florida. No significant sustained CO₂ treatment effects …

Downstream Pathway Activation In Cultured Hepatocytes Following Treatment With Francisella Tularensis, Nicole Wakefield

Undergraduate Theses and Capstone Projects

Francisella tularensis, the intracellular pathogen that causes tularemia, was investigated to determine how it infects and replicates within mammalian hepatocytes. To date, it has been shown that hepatocytes can be infected by F. tularensis and that this causes considerable change in the protein phosphorylation state of several vital signaling molecules within the host cell. Protein kinase pathways can be mapped as signatures of infection. Hepatocytes tend to be susceptible to infection by F. tularensis, thus stimulating internal signaling. The Francisella strains used were selected with the goal of producing a model that can be used to elucidate the cell signaling …

Identification And Catalog Of Holocene And Late Pleistocene Chiropteran Fossils From Hamilton County, Tn, Ashley Miller

Honors Theses

Caves play an essential role in our understanding of the Pleistocene Epoch. Caves represent the largest percentage of known North American Pleistocene faunas (Kurten and Anderson, 1980). These unique environments provide stable erosion free conditions that allow fossils to remain preserved for thousands, if not millions, of years (Corgan, 1996; Schubert et al., 2003). The fossil remains found in caves can help paleontologists document biogeographic and evolutionary patterns in a great variety of organisms (Schubert et al., 2003). Many fossils found in cave deposits only date to the Holocene (Schubert et al., 2003). These fossils localities are rarely studied by …

Frequency Of Sublethal Injury In A Deepwater Ophiuroid, Ophiacantha Bidentata, An Important Component Of Western Atlantic Lophelia Reef Communities, R. Allen Brooks, Martha S. Nizinski, Steve W. Ross, Kenneth J. Sulak

United States Geological Survey: Staff Publications

The occurrence and relative abundance of tissue (arm) regeneration in the ophiuroid, Ophiacantha bidentata (Retzius), was examined in individuals collected primarily among colonies of the deep-water coral Lophelia pertusa off the southeastern United States. Seven deep-water coral sites (384–756 m), located between Cape Lookout, NC, and Cape Canaveral, FL, were sampled in June 2004 using a manned submersible. The presence of regenerative tissue was evaluated by visual inspection of each individual ophiuroid, and the proportion of regenerating arms per individual was examined relative to size of individual, geographic location, and depth of collection. Ophiacantha bidentata, the dominant brittle star collected, …

Frequency-Dependent Attenuation Analysis Of Ground-Penetrating Radar Data, John H. Bradford

CGISS Publications and Presentations

In the early 1990s, it was established empirically that, in many materials, ground-penetrating radar (GPR) attenuation is approximately linear with frequency over the bandwidth of a typical pulse. Further, a frequency-independent Q* parameter characterizes the slope of the band-limited attenuation versus frequency curve. Here, I derive the band-limited Q* function from a first-order Taylor expansion of the attenuation coefficient. This approach provides a basis for computing Q* from any arbitrary dielectric permittivity model. For Cole-Cole relaxation, I find good correlation between the first-order Q* approximation and Q* computed from linear fits to the attenuation coefficient …

Evidence For Prehistoric Coseismic Folding Along The Tsaotun Segment Of The Chelungpu Fault Near Nan-Tou, Taiwan, Ashley R. Streig, Charles M. Rubin, Wen-Shan Chen, Long-Shen Lee, Stephen C. Thompson, Chris Madden, Shih-Ting Lu

All Faculty Scholarship for the College of the Sciences

Taiwan's 1999 M_w 7.6 earthquake generated over 85 km surface rupture along the Chelungpu thrust fault. Paleoseismic studies at the Shi‐Jia site near Nantou city, reveal folding as the predominant form of deformation. Stratigraphic relations across the 1999 fold scarp show the style and degree of deformation caused by the penultimate event is similar to observed 1999 deformation. A boring transect across the fold scarp provides additional evidence of an earlier earthquake. Investigations at the Shi‐Jia site revealed three prehistoric events; accelerator mass spectrometry (AMS) radiocarbon ages indicate that the penultimate earthquake occurred between 1160 and 1440 A.D. Paleoseismic …

Particulate Organic Carbon Fluxes Along Upwelling‐Dominated Continental Margins: Rates And Mechanisms, Robert Thunell, Claudia R. Benitez-Nelson, Ramon Varela, Yrene Astor, Frank Muller‐Karger

Faculty Publications

[1] Time series sediment trap samples were used to examine the rates and mechanisms of particulate organic carbon (POC) flux at three continental margin locations, Santa Barbara Basin, Cariaco Basin, and Guaymas Basin, marked by seasonal upwelling and high primary production. The mean POC flux in Santa Barbara Basin (0.096 g m−2 d−1) is nearly twice that of Cariaco Basin and 4 times higher than that in Guaymas Basin, with all three sites having POC fluxes significantly higher than the open ocean average (0.007 g m−2 d−1). In Cariaco Basin, the only site with available primary production numbers, there is …

Submarine Volcanic Morphology Of The Western Galapagos Based On Em300 Bathymetry And Mr1 Side-Scan Sonar, Jennifer B. Glass, D J. Fornari, Hillary F. Hall, Allison A. Cougan, Heidi A. Berkenbosch, Mark L. Holmes, Scott M. White, Giorgio De La Torre

Faculty Publications

A compilation of high-resolution EM300 multibeam bathymetric and existing MR1 side-scan sonar data was used to investigate the volcanic morphology of the flanks of the western Galapagos Islands. The data portray an assortment of constructional volcanic features on the shallow to deep submarine flanks of Fernandina, Isabela, and Santiago Islands, including rift zones and groups of cones that are considered to be the primary elements in constructing the archipelagic apron. Ten submarine rift zones were mapped, ranging in length from 5 to 20 km, comparable in length to western Canary Island rift zones but significantly shorter than Hawaiian submarine rift …

Solute Chemistry And Isotopic Investigation Of The Groundwater Flow Paths In Honey Lake Basin, Lassen County, California And Washoe County, Nevada, Rachel M. Henderson

Theses and Dissertations

Honey Lake Basin is a large, hydrologically closed valley with two playa lakes that are separated by a low elevation sill. The Basin has a complex hydrogeologic setting, with numerous groundwater flow paths that interact with surface waters and three basic aquifers; shallow, deep, and geothermal. Thirteen flow paths; eleven cold and two thermal, are identified and the geochemical evolution of those paths are characterized by integrating solute chemistry and isotopic data. The chemical flow paths include recharge in either granitoid or volcanic terrains in the Sierra Nevada Range and the Modoc Plateau, respectively. The groundwater then flows through alluvial …

Pre-Historic Landslides On The Southeast Flank Of The Uinta Mountains, Utah: Character And Causes Of Slope Failure, Todd D. Bradfield

Theses and Dissertations

More than 100 landslides have been mapped along the southeast flank of the Uinta Mountains. Large landslide deposits are up to 4.6 kilometers long and have an area of approximately 5-9 km². Landslide types include multiple and successive rock slumps, debris slumps and debris flows. Most landslides have a main head scarp in the Bishop Conglomerate and the large landslides have many minor scarps. Multiple slump blocks are manifest by repeated transverse ridges and trenches in the head area of some landslides. Most body and toe areas are deeply incised by gully erosion (up to 91 meters deep) and drainages …

Leaks In The Pipeline: Why Do Women Remain Curiously Absent From The Ranks Of Academia?, Mary Anne Holmes

Department of Earth and Atmospheric Sciences: Faculty Publications

Family issues can cause women to abandon academia at every rung of the career ladder. Policy-makers have addressed some ways to get more women on to the lower rungs of the ladder. But solutions at the higher steps—tenure and beyond—are proving a little more difficult.

Structural Analysis Of Rock Canyon Near Provo, Utah, Laura Cardon Wald

Theses and Dissertations

A detailed structural study of Rock Canyon (near Provo, Utah) provides insight into Wasatch Range tectonics and fold-thrust belt kinematics. Excellent exposures along the E-W trending canyon allow the use of digital photography in conjunction with traditional field methods for a thorough analysis of Rock Canyon's structural features. Detailed photomontages and geometric and kinematic analyses of some structural features help to pinpoint deformation mechanisms active during the canyon's tectonic history. Large-scale images and these structural data are synthesized in a balanced cross section, which is used to reconstruct the structural evolution of this portion of the range. Projection of surficial …

The Origins Of Four Paterae Of Malea Planum, Mars, Susan K. Larson

Theses and Dissertations

Malea Planum is a volcanic plain on the southern rim of Hellas Planitia, the largest impact basin on Mars. Four large circular structures on Malea Planum have traditionally been identified as paterae, or low relief, central vent volcanoes (Plescia and Saunders, 1979). A geologic map was constructed and new crater counts made to explore the ages and origins of the paterae. Amphitrites and Peneus Paterae have radial patterns of wrinkle ridges on their flanks and distinct summit calderas (95 km and 130 km across) with arcuate bounding scarps. In contrast, Malea and Pityusa Paterae are broad depressions with diameters greater …

Modified Kubelka-Munk Equations For Localized Waves Inside A Layered Medium, Kasper Van Wijk

CGISS Publications and Presentations

We present a pair of coupled partial differential equations to describe the evolution of the average total intensity and intensity flux of a wave field inside a randomly layered medium. These equations represent a modification of the Kubelka-Munk equations, or radiative transfer. Our modification accounts for wave interference (e.g., localization), which is neglected in radiative transfer. We numerically solve the modified Kubelka-Munk equations and compare the results to radiative transfer as well as to simulations of the wave equation with randomly located thin layers.

Scoping Report For The Glen Canyon Dam Long-Term Experimental Plan Environmental Impact Statement, U.S. Department Of The Interior, Bureau Of Reclamation

All U.S. Government Documents (Utah Regional Depository)

This report summarizes the issues raised during the initial scoping process for the Bureau of Reclamation's Long-term Experimental Plan for Glen Canyon Dam Operations and Other Management Actions Environmental Impact Statement (EIS). This report describes the initial scoping process and presents the schedule, describes the scoping meetings, summarizes comments submitted by the public, and provides an overview of the relevant issues that Reclamation anticipates will be analyzed in the EIS.

Scoping is defined by the regulations implementing the National Environmental Policy Act (NEPA) as the process whereby lead agencies solicit input from the public on what the issues and alternatives …

Spatial Variation In Sea Urchins, Fish Predators, And Bioerosion Rates On Coral Reefs Of Belize, Jocelyn Brown-Saracino, Paulette Peckol, H. Allen Curran, Martha L. Robbart

Biological Sciences: Faculty Publications

Although sea urchins are critical for controlling macroalgae on heavily fished coral reefs, high densities threaten reefs, as urchins are also prodigous bioeroders. This study examined urchin population characteristics, bioerosion rates, their fish predators (Labridae), and potential competitors (Scaridae) on unprotected reefs and a reef within a marine protected area (MPA) in the lagoonal regions off Belize. Urchin density (<1 >m-2) and bioerosion rates (∼0.2 kg CaCO3m-2year-1) were lowest and members of the Labridae were the highest (∼20 fish 200 m-3) within the MPA, while several unprotected reefs had higher (∼18-40 m-2) urchin densities, lower Labridae abundances (1-3 fish 200 …

The Evolution Of Zinjanthropus Boisei, Paul J. Constantino, Bernard A. Wood

Biological Sciences Faculty Research

Many people assume that OH 5, the type specimen of Paranthropus boisei, collected in 1959, was the first evidence of that taxon to be found, but OH 3, recovered in 1955, predated the discovery of OH 5 by four years. Thus, Paranthropus boisei recently celebrated the equivalent of its fiftieth birthday. This review marks that milestone by examining the way our understanding of this taxon has changed during its fifty, or so, year history.

Geodetic, Teleseismic, And Strong Motion Constraints On Slip From Recent Southern Peru Subduction Zone Earthquakes, M. E. Pritchard, E. O. Norabuena, C. Ji, R. Boroschek, D. Comte, M. Simons, Timothy H. Dixon, P. A. Rosen

School of Geosciences Faculty and Staff Publications

We use seismic and geodetic data both jointly and separately to constrain coseismic slip from the 12 November 1996 M_w 7.7 and 23 June 2001 M_w 8.5 southern Peru subduction zone earthquakes, as well as two large aftershocks following the 2001 earthquake on 26 June and 7 July 2001. We use all available data in our inversions: GPS, interferometric synthetic aperture radar (InSAR) from the ERS-1, ERS-2, JERS, and RADARSAT-1 satellites, and seismic data from teleseismic and strong motion stations. Our two-dimensional slip models derived from only teleseismic body waves from South American subduction zone earthquakes with M …

Lacustrine Evidence For Moisture Changes In The Nebraska Sand Hills During Marine Isotope Stage 3, Kimberly C. Jacobs, Sherilyn C. Fritz, James B. Swinehart

Department of Earth and Atmospheric Sciences: Faculty Publications

In the central Great Plains of North America, loess stratigraphy suggests that climate during the late Pleistocene was cold and dry. However, this record is discontinuous, and there are few other records of late-Pleistocene conditions. Cobb Basin, located on the northern edge of the Nebraska Sand Hills, contains lacustrine sediments deposited during Marine Isotope Stage 3, beginning approximately 45,000 cal yr BP and continuing for at least 10,000 yr. The lake was formed by a dune dam blockage on the ancient Niobrara River, and its deposits contain a diatom record that indicates changes through time in lake depth driven by …

Preliminary Results Of A Fecal Microbe Survey In An Eutrophic Lake, Wilgreen Lake, Madison County, Kentucky, Walter S. Borowski, Michael S. Albright

EKU Faculty and Staff Scholarship

Wilgreen Lake is a small (~14 mi²) eutrophic lake formed by damming several tributary streams to Silver Creek, Madison County, Kentucky. The lake receives runoff from industrial and urban areas (Richmond) that comprise ~10% of the total watershed area; most runoff is from cattle pasture or human developments encircling the lake. Present and past developments are on septic systems, and effluent from these systems is known qualitatively to seep into lake waters.

Our research group is currently conducting a study of the lake in order to identify major nutrient sources, and one possible tracer method is to quantitatively …

Sulfur Geochemistry And Diagenesis In A Gas Hydrate Terrane, Cascadia Margin, Offshore Oregon: Role Of Anaerobic Methane Oxidation, David Deigert, Walter S. Borowski

EKU Faculty and Staff Scholarship

We present sulfide mineral data from south Hydrate Ridge located in a gas hydrate terrane, offshore Oregon. Sulfide sulfur concentration and the isotopic composition of sulfur (d³⁴S) in authigenic sulfide minerals are analyzed from sediment samples collected on Ocean Drilling Project (ODP) Leg 204. Shallow sediment samples (<25 >mbsf) assess the relative importance of anaerobic methane oxidation (AMO) as a biogeochemical process, both here and at the Blake Ridge, another well known gas hydrate terrane offshore southeastern United States. Deep samples (>25 mbsf) are used to evaluate sulfur diagenesis and its controls from early Pleistocene to the …

Sedimentology Of Acid Saline Lakes In Southern Western Australia: Newly Described Processes And Products Of An Extreme Environment, Kathleen Counter Benison, Brenda Beitler Bowen, Francisca Oboh-Ikuenobe, Elliot A. Jagniecki, Deidre A. Laclair, Stacy L. Story, Melanie R. Mormile, Boyoung Hong

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Naturally acid saline systems with pH values between 1.7 and 4 are common on the Yilgarn Craton of southern Western Australia. a combination of physical and chemical processes here yield a previously undescribed type of modern sedimentary environment. Flooding, evapoconcentration, desiccation, and eolian transport at the surface, as well as influx of acid saline groundwaters, strongly influence these lakes. Halite, gypsum, kaolinite, and iron oxides precipitate from acid hypersaline lake waters. Shallow acid saline groundwaters affect the sediments of the lakes and associated mudflats, sandflats, channels, and dunes by precipitating early diagenetic halite, gypsum, iron oxides, clays, jarosite, and alunite. …

Residence Times And Temporal Variations Of 210Po In Aerosols And Precipitation From Southeastern Michigan, United States, Daphne Mcneary, Mark Baskaran

Environmental Science and Geology Faculty Research Publications

Daughter products of ²²²Rn (such as ²¹⁰Pb, half-life = 22.1 years, and ²¹⁰Po, half-life = 138 days) have been widely used as tracers to determine the removal rates of aerosols as well to obtain analog information on the behavior of other chemical species in the lower atmosphere. To establish the first data set on the depositional fluxes of ²¹⁰Po in bulk precipitation and concentrations in air samples from the midwestern United States, we measured the depositional fluxes of ²¹⁰Pb and ²¹⁰Po in the bulk (wet plus dry) and dry fallout by deploying a rain …

How I Produced Nationally Award Winning Alfalfa Hay, Rick Alexander

Kentucky Alfalfa and Stored Forage Conference

No abstract provided.

Roundup Ready Alfalfa: Results After One Year On The Market, S. Ray Smith

Kentucky Alfalfa and Stored Forage Conference

Roundup Ready alfalfa has now been on the market for over a year with close to 30 varieties available or soon to be available across the U.S. This technology provides many new options for alfalfa producers in Kentucky. Several people have asked us which variety is highest yielding and unfortunately we have not been able to provide a good answer. The technology is so new (just approved fall 2005) that few of these varieties have been entered into University yield trials. Companies do have some private data, but they often don’t compare to the varieties you are familiar with. So …

Cowpea Aphids: Where Did They Come From, Will They Be Back?, Lee H. Townsend

Kentucky Alfalfa and Stored Forage Conference

Clearly, something was unusual back in March when large numbers of very dark aphids were found covering stems and tips in Logan, Marion, and Barren counties. They were the cowpea aphid or black legume aphid (Aphis craccivora), a sap-feeding insect known to occur in at least 28 states scattered over the US and into Canada. The cowpea aphid is the only black aphid found infesting alfalfa. Winged or wingless adults are usually shiny black, while the smaller nymphs are dull gray to black. Usually. they are lined along stems or clustered in the expanding leaf tips.

Hay Heating, Hay Sweat And Spontaneous Combustion, Tom Keene, Doug Overhults

Kentucky Alfalfa and Stored Forage Conference

Making hay in central Kentucky can be one of the most trying on farm endeavors a producer can undertake. Our plentiful moisture, rolling topography, and climate make Kentucky ideal for producing high quality forage for either grazing or hay making. However, that same moisture either in the form of rain or high humidity can sometimes make it devilishly hard to make quality hay here in Kentucky.

Alfalfa For Summer Grazing, John Johns

Kentucky Alfalfa and Stored Forage Conference

Alfalfa can make an excellent grazing forage for cattle in the summer as well as at other times of year provided that good grazing management is utilized. Alfalfa can be grazed very close to the ground but should not be grazed continuously. Initial regrowth after grazing comes from nutrient reserves in the root; therefore, a sufficient rest period or regrowth period without grazing must be allowed for these nutrients to be replenished. In summer, this rest period is 30 to 35 days. In adequate rest for root nutrient replenishment is not allowed, the plant will be weakened and stand life …