Digital Commons Network^™

Estimating Soil Seed Bank Characteristics In Ponderosa Pine Forests Using Vegetation And Forest-Floor Data, Scott R. Abella, Judith D. Springer

Public Policy and Leadership Faculty Research

Soil seed banks are important for vegetation management because they contain propagules of species that may be considered desirable or undesirable for site colonization after management and disturbance events. Knowledge of seed bank size and composition before planning management activities facilitates proactive management by providing early alerts of exotic species presence and of abilities of seed banks to promote colonization by desirable species. We developed models in ponderosa pine (Pinus ponderosa) forests in northern Arizona to estimate the size and richness of mineral soil seed banks using readily observable vegetation and forestfloor characteristics. Regression models using three or fewer predictors …

Lime For High Rainfall Pastures: Above 800mm Average Annual Rainfall, Mike Bolland, Bill Russell

Bulletins 4000 -

Conventional agriculture acidifies soil. As your soil becomes more acid, productive pasture species disappear and are replaced by species of low agricultural value. It is a waste of money to apply expensive fertiliser to pastures which are inherently poorly productive because they are growing in an acid soil.

The paper examines the types of lime available, how to select lime for quality and when and how much lime to apply. Maganese toxity and aluminum toxicity are examine, how to test your soil, and affect of soil acidity on bacteria and other microorgansims.

Optlime, A Bioecenomic Model Of Soil Acidity Management In Agricultural Systems, Chris Gazey

All other publications

Optlime is a model that represents the essential biological, physical and economic factors related to soil acidity management in Western Australia. The model allows users to define site and soil characteristics for an acidic scenario and then simultaneously assess likely outcomes for 2 different lime sources and application strategies. With and without liming scenarios are examined over a 20 year simulation so as to capture the long-term impacts of soil acidity management. Output provided allows you to examine the likely effect of liming on pH, exchangeable aluminium, yields, and profits. An investment appraisal is provided to show you how liming …

Cancellation Of Spurious Arrivals In Green’S Function Extraction, Kasper Van Wijk

CGISS Publications and Presentations

The extraction of the Green's function by cross correlation of waves recorded at two receivers nowadays finds much application. We show that for an arbitrary small scatterer, the cross terms of scattered waves give an unphysical wave with an arrival time that is independent of the source position. This constitutes an apparent inconsistency because theory predicts that such spurious arrivals do not arise, after integration over a complete source aperture. This puzzling inconsistency can be resolved for an arbitrary scatterer by integrating the contribution of all sources in the stationary phase approximation to show that the stationary phase contributions to …

Ground-Penetrating Radar And Thermal Modeling Of Active Layer Thaw Beneath Arctic Streams, Troy Richard Brosten

Boise State University Theses and Dissertations

Seasonal thaw depth beneath arctic streams significantly impacts physical and biological processes within arctic stream environments. The impact of greater seasonal thaw for extended periods of time can alter ecosystems that have, in the past, resulted from more prevalent permafrost environments. Effects of climatic change on arctic stream environments necessitate the need for more information on characteristics of seasonal thaw and processes that occur within the thawed layer. Multiple ground-penetrating radar (GPR) methods and one-dimensional (1D) thermal modeling were used to investigate seasonal thaw beneath arctic streams and determine the dominant thermal process.

Study sites were selected to include stream …

Pcor Partnership Atlas, Wesley D. Peck, Barry W. Botnen, Lisa S. Botnen, Daniel J. Daly, John A. Harju, Melanie D. Jensen, Erin M. O'Leary, Steven A. Smith, James A. Sorensen, Edward N. Steadman, Stephanie L. Wolfe, Darin R. Damiani, John T. Litynski, David W. Fischer

EERC Maps and Infographics

The Plains CO₂ Reduction (PCOR) Partnership Atlas, revised 2nd edition, introduces global climate change and provides a regional profile of CO₂ sources and potential sinks across the PCOR Partnership region. Carbon sequestration offers a promising set of technologies through which CO₂ can be stored for long periods of time.

Loess Record Of The Pleistocene–Holocene Transition On The Northern And Central Great Plains, Usa, Joseph A. Mason, Xiaodong Miao, P.R. Hanson, William C. Johnson, Peter M. Jacobs, Ronald J. Goble

Department of Earth and Atmospheric Sciences: Faculty Publications

Various lines of evidence support conflicting interpretations of the timing, abruptness, and nature of climate change in the Great Plains during the Pleistocene–Holocene transition. Loess deposits and paleosols on both the central and northern Great Plains provide a valuable record that can help address these issues. A synthesis of new and previously reported optical and radiocarbon ages indicates that the Brady Soil, which marks the boundary between late Pleistocene Peoria Loess and Holocene Bignell Loess, began forming after a reduction in the rate of Peoria Loess accumulation that most likely occurred between 13.5 and 15 cal ka. Brady Soil formation …

Direct Evidence From Anisotropy Of Magnetic Susceptibility For Lateral Melt Migration At Superfast Spreading Centers, R. J. Varga, Andrew J. Horst, J. S. Gee, J. A. Karson

Natural Resources and Earth Sciences Faculty Research

Rare, fault‐bounded escarpments expose natural cross sections of ocean crust in several areas and provide an unparalleled opportunity to study the end products of tectonic and magmatic processes that operated at depth beneath oceanic spreading centers. We mapped the geologic structure of ocean crust produced at the East Pacific Rise (EPR) and now exposed along steep cliffs of the Pito Deep Rift near the northern edge of the Easter microplate. The upper oceanic crust in this area is typified by basaltic lavas underlain by a sheeted dike complex comprising northeast striking, moderately to steeply southeast dipping dikes. Paleomagnetic remanence of …

Erosion And Trail Building: A Case Study Of The East Tennessee State University Trail System., Joshua Callahan

Electronic Theses and Dissertations

Natural and accelerated erosion from trail users affects the sustainability of trail systems. Designing and building sustainable trail systems will greatly decrease the effect that erosion has on a trail. Trails that allow multiple types of users, such as hiking and mountain biking, must be able to sustain both groups. At East Tennessee State University the trail system was originally designed for hiking. Mountain bikers have become the main user group on the trail system leading to erosion problems on certain areas of the trail due to trail design flaws. The study seeks to identify the problem areas of trail …

Relating Groundwater To Seasonal Wetlands In Southeastern Wisconsin, Usa, John D. Skalbeck, Donald M. Reed, Randall J. Hunt, Jamie D. Lambert

United States Geological Survey: Staff Publications

Historically, drier types of wetlands have been difficult to characterize and are not well researched. Nonetheless, they are considered to reflect the precipitation history with little, if any, regard for possible relation to groundwater. Two seasonal coastal wetland types (wet prairie, sedge meadow) were investigated during three growing seasons at three sites in the Lake Michigan Basin, Wisconsin, USA. The six seasonal wetlands were characterized using standard soil and vegetation techniques and groundwater measurements from the shallow and deep systems. They all met wetland hydrology criteria (e.g., water within 30 cm of land surface for 5% of the growing season) …

A Microanalytical Approach To Understanding The Origin Of Cumulate Xenoliths From Mauna Kea, Hawaii, Megan Pickard

Theses and Dissertations

Cumulate xenoliths erupted with alkalic hawaiite lavas from a postshield cinder cone on Mauna Kea, Hawaii include a variety of mafic and ultramafic rock types. Previous studies of major and trace element compositions of minerals in the xenoliths are interpreted to show transitional to alkalic magma parentages from the postshield stage, although any orthopyroxene-bearing xenoliths are considered to have tholeiitic parents. Major element compositions minerals were analyzed using the electron microprobe and trace element compositions of clinopyroxene grains were analyzed by laser ablation inductively coupled plasma mass spectrometry. In this study, major element compositions of clinopyroxene, olivine and plagioclase grains …

Magmatic Sulfur And Chlorine Abundances At Stromboli, Italy And Their Role In The Formation Of Vesicle-Hosted Metal Alloys, Nichelle Lynn Baxter

Theses and Dissertations

Strand et al. (2002) discovered small metal alloy grains rich in Cu, Co, and Sn (maximum size 150 µm) in vesicles of lava from Kilauea Volcano. These alloys are also found in basaltic rocks of several Italian volcanoes. To better understand the origin of these metal-rich grains, bombs from Stromboli Volcano were examined. Two bomb types were collected from Stromboli: pumiceous bombs and scoriaceous bombs. Bulk rock trace element geochemistry indicates that there are no significant differences in Cu, Co, or Sn (the three major components of the metal alloys) between the pumiceous and scoriaceous bombs. Comparison of olivine melt …

Stereospecificity In Glucose Consumption: A New Approach To Martian Life Detection, Vienna R. Saccomanno, Henry J. Sun

Undergraduate Research Opportunities Program (UROP)

In 1976, the Viking mission made a remarkable discovery: Martian soil was capable of decomposing an organic nutrient broth to carbon dioxide as if it contained live microorganisms. However, a biological interpretation of this finding is in apparent contradiction with the gas chromatograph-mass spectrometer aboard the Viking landers, which showed Martian soil to be devoid of indigenous organics. To reconcile these findings, it has been hypothesized that unknown abiotic oxidants, such as peroxide and superoxide, are present on Mars and that they were responsible for its soil reactivity. The objective of this research is to develop a life detection method …

Potential Antimicrobial Properties Of The Cyanobacterium Microcoleus Vaginatus In Relationship To The Moss Bryum Argenteum, Crystal Erickson, Lloyd Stark

Undergraduate Research Opportunities Program (UROP)

Biological soil crusts play important ecological roles in arid desert regions. These crusts cycle nutrients, prevent wind/water erosion, and form the basis of food chains and soil formation in desert communities. Primary components of these structures include two desert moss species Bryum argenteum and Syntrichia caninervis, and Microcoleus vaginatus, a cyanobacterium. Our Phase I experiment strongly suggests that in an environment of intense light, a condition of stress to Syntrichia caninervis, there is an increase in shoot regeneration when cyanobacteria are present compared to when they are absent. Microcoleus is a highly motile species and our lab observations of fewer …

Magnetic Ordering Phase Transitions Of Gd2sn2o7, Gordon Tam, Andrew Cornelius, Daniel Antonio

Undergraduate Research Opportunities Program (UROP)

Pyrochlores with magnetic rare earth ions are a topic of interest due to unusual results brought about by their high degree of geometrical frustration. The lattice structure prevents the magnetic spin interactions from finding a single minimum energy state, which leads to a nonzero residual entropy[1]. By analyzing the heat capacity at low temperatures, the type of magnetic interaction can be determined and the temperatures at which long-range magnetic ordering and magnetic field induced splitting of energy states occur.

Modeling The Deformation Of Fayalite, Greg Hoth, Mike Brawner, Pamela Burnley

Undergraduate Research Opportunities Program (UROP)

We are studying how the mineral fayalite deforms under stress while it is subject to high pressures and temperatures. Specifically, we are analyzing x-ray diffraction spectra obtained from experiments with the D-DIA apparatus at Brookhaven national labs. By fitting peaks to the diffraction spectra, we can calculate the spacing between lattice planes of fayalite and so we can observe how this spacing changes over time as the crystal structure deforms We hope to show that this deformation can be modeled using an Elastic Plastic Self Consistent model. In such a model, the material is treated as a cluster of independently …

Phonon Density Of States Of Iron Solid Solutions At Ambient And High Pressures Using Nuclear Inelastic X-Ray Scattering (Nrixs), Samantha L. Combs, Elizabeth A. Tanis, Malcolm Nicol

Undergraduate Research Opportunities Program (UROP)

Nuclear resonant inelastic x-ray scattering (NRIXS) of synchrotron radiation uses the energy transferred during the inelastic nuclear absorption of photons to determine phonon density of states for solid Mössbauer isotopes. This type of experiment can be conducted at ambient and high pressures with the use of a diamond anvil cell (DAC) and a rhenium gasket. Here, we are concerned with the phonon DOS of α-FePt 10% at pressures up to 30 GPa, as well as FeAl 4.3%, 6.4%, and 27.1% at ambient pressures. The iron samples used are doped in order to increase the pressure at which the alpha to …

A Study Of Nife(X)Cr(2-X)O4 By Laser Micro-Raman Spectroscopy, Lucas Wilson, Markus Vasquez, John Farley, Allen L. Johnson, Brian D. Hosterman

Undergraduate Research Opportunities Program (UROP)

Standards of spinels, composed of two metals and oxygen with the formula AB2O4, are being created with known composition to identify spinels in samples of unknown composition by comparison with the spectra obtained from the standards. Laser micro-Raman spectroscopy allows the identification of chemical species based on their unique vibrational modes. The degree to which spinels of varying composition can be identified will be determined. This will aid in the study of the corrosion of steel by liquid metal. Spinels are a likely component of the oxide layer. Understanding the composition of the products of corrosion leads to an understanding …

Pre-Eruptive Conditions Of The Oligocene Wah Wah Springs Tuff, Southeastern Great Basin Ignimbrite Province, Kurtus Steven Woolf

Theses and Dissertations

The Wah Wah Springs Tuff (30.0 Ma) is one of several very large volume ash-flow tuffs (>3200 km³ of erupted magma) that were emplaced near the peak of the flare-up of activity in the Great Basin ignimbrite province of western North America. It can be characterized as a "monotonous intermediate" ignimbrite because of its intermediate concentrations of silica (~63 to ~70 wt. %), apparent uniform chemical and mineralogical characteristics, and crystal-rich nature (32 ± 10 % phenocrysts on a dense rock basis). The major phase assemblage found throughout deposit is similar to other monotonous intermediates with a few exceptions …

Geology And Hydrology Of Karst In West-Central And North-Central Florida, Lee J. Florea

Earth, Environmental, and Atmospheric Sciences Faculty Publications

The state of Florida is blessed with the highest density of large springs in North America and hundreds of smaller springs where the water from limestone aquifers returns to the surface (Scott et al., 2004). Spectacular underwater caves supply water to these springs. Lesser known are the equally fantastic air-filled caves of Florida and South Georgia (Florea, 2006; Lane, 1986). This paper features these underwater and airfilled caves, explores the impact of changes in sea level on karst in this near-coastal environment, and establishes several geologic and hydrologic characteristics that distinguish karst in the limestones of the southeast from karst …

Controls On Longitudinal Profiles In Headwater Rivers Of The Waipaoa Basin, North Island, New Zealand, David M. Livingston

All-Inclusive List of Electronic Theses and Dissertations

The longitudinal profiles of the adjacent Mangatu and Upper Waipaoa Rivers, of the Waipaoa basin of the North Island of New Zealand, differ in their form despite their similarity in size and that they flow over comparable bedrock. AdditionaJly, both basins have experienced an increase in sediment supply following deforestation during the 19th and 20th centuries. This research addresses how the deviations in the long profiles of the Mangatu and Upper Waipaoa Rivers have arisen and what effect the increased sediment loading has had on their form. Using methods similar to those of Hack (1957), who found that in same …

Geoarchaeological And Paleolandscape Reconstructions In The Lower Ohio River Valley: Late Wisconsin And Early Holocene Landforms In Knob Creek Bottom, Nathan Christopher Scholl

All-Inclusive List of Electronic Theses and Dissertations

This study examines a paleolandscape model that focuses on alluvial landforms that date to the Late Pleistocene and Early Holocene in Knob Creek bottom of the lower Ohio River valley. The study tests and refines a landscape model based on geoarchaeological data from the Caesars Archaeological Project. Analysis centers on the relationship between late Wisconsin and early Holocene Landform Sediment Assemblages (LSA), including early paleochannels. For this analysis a series of soil cores was extracted from the LSA understudy and described using standard USDA terminology. Additional analysis included particle size analysis using a hydrometer to determine textural composition of core …

Remote Sensing Studies For The Assessment Of Geohazards: Toxic Algal Blooms In The Lower Great Lakes, And The Land Subsidence In The Nile Delta, Richard H. Becker

Dissertations

Remote sensing techniques provide valuable tools for assessing a wide variety of environmental phenomena. They have been used for monitoring and assessment of various types of geologic and environmental hazards occurring on land, in the air, or in oceans. I present results from two studies, the first of which examines the spatial and temporal distribution of algal blooms in the Great Lakes; the second measures subsidence in the Nile Delta.

In the first study, methodologies to investigate the extent and distribution (temporally and spatially) of algal blooms in Lake Erie and Lake Ontario are studied. Millions of people in the …

A Spatial Analysis Of Anthropogenically Derived And Naturally Occurring Environmental Controls On Corn-Based Ethanol Production In Nebraska, Nathan Charles Healey

School of Natural Resources: Dissertations, Theses, and Student Research

Transportation fuels are an integral part of political, economic, social, and environmental arenas. Traditionally, fossil fuels have been utilized most heavily due to their abundance and economic value. Currently, social and political concerns about harmful emissions (greenhouse gases) from fossil fuel combustion have enhanced interest in alternative fuels that do not have the same environmental consequence. Numerous alternative fuels are produced globally including methanol, biodiesel, hydrogen cells, and ethanol (ethyl alcohol). In America, ethanol is produced from com due to the existence of the "Com Belt" and abundant corn production. Understanding the capacity for America to sustain expansion of alternative …

Influence Of Bioirrigation On Metal Distribution Within Burrows, Terri Shattuck

Masters Theses

Bioirrigation is the increase of solute transport resulting from introduction of oxygenated water from the surface into the more reduced environment deep within the burrow. Fe and Mn hydr-(oxides) accumulate on burrow margins in response to the oxygen flux into suboxic porewaters. This has been shown to trap trace metals (Harding and Risk, 1986; Tessier and Campbell, 1988; Tessier et al., 1979, 1982). The diagenesis, mobility, and transport of metals contribute to the bioavailability of metals in the environment possibly to the extent of harming ecosystems; especially in coastal areas with buried waste. This study assesses Fe and trace metal …

Fish Distributions And Nutrient Cycling In Streams: Can Fish Create Biogeochemical Hotspots, Peter B. Mcintyre, Alexander S. Flecker, Michael J. Vanni, James M. Hood, Brad W. Taylor, Steven A. Thomas

Dartmouth Scholarship

Rates of biogeochemical processes often vary widely in space and time, and characterizing this variation is critical for understanding ecosystem functioning. In streams, spatial hotspots of nutrient transformations are generally attributed to physical and microbial processes. Here we examine the potential for heterogeneous distributions of fish to generate hotspots of nutrient recycling. We measured nitrogen (N) and phosphorus (P) excretion rates of 47 species of fish in an N-limited Neotropical stream, and we combined these data with population densities in each of 49 stream channel units to estimate unit- and reach-scale nutrient recycling. Species varied widely in rates of N …

The Mayan Ice Cap: Glacial Geology And Paleoclimate Of The Northern Guatemalan Highlands, Alex Joseph Roy

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Sierra de los Cuchumatanes region of the northern Guatemalan highlands supported a large plateau ice cap with an area of -40 km2 along with a group of 5 cirque glaciers -1 to 2 km2 during the local last glacial maximum (LLGM). A comprehensive mapping reconstruction of the northern Guatemalan highlands is presented here, including glacial geology and an estimate of maximum ice limits from physical evidence and computer modeling. The glacial geologic map was produced via field mapping with global positioning system (GPS) surveying combined with aerial stereo photographic and topographic map analysis. This new field work on moraine …

Kinematics And Timing Of Orogen-Parallel Flow, Grouse Creek Mountains, Utah, Tonia Gail Arriola

UNLV Theses, Dissertations, Professional Papers, and Capstones

Alternating contractional and extensional events in orogenic belts play a significant role in dynamically adjusting crustal thickness during regional contraction. Distinguishing between these two contrasting kinematic regimes is not only important for understanding the tectonic setting but also provides insights into the dynamics of evolving orogenic wedges. The earliest pervasive fabric, D ₁ , in the Grouse Creek Mountains of northwest Utah is interpreted to have played an integral role in accommodating such a dynamic adjustment. It is interpreted that focused crustal thickening led to differences in gravitational potential energy along strike, facilitating an episode of mid-Cretaceous synconvergent orogen-parallel extension. …

Optimization And Validation Of An Enzymatic Method To Quantify Glucose In Potato Tubers, Engil Isadora Pujol Pereira, Tatiana Emanuelli, Dilson Antonio Bisognin, Sergio T. De Freitas

School of Earth, Environmental, & Marine Sciences Faculty Publications

The processing industry requires potato tubers with low levels of reduced sugars, glucose and fructose, which is responsible for the whiteness of the chip color. The objective of this research was to optimize and validate a simple, inexpensive, and precise enzymatic method to quantify glucose in potato tubers. This method will be useful in breeding programs to select clones for processing purposes with low levels of glucose. The validation procedure followed the recommendations described in INMETRO document DOQ-CGCRE-008 in 2003. The method was linear between 1.25 to 40µg of glucose in the sample. The quantification limit was 0.319mg g-1 of …

A Comparison Of Sequential And Integrated Data Fusion For Estimating Hydrologic Properties During A Synthetic Gpr Monitored Infiltration Event, Guy Sicilia Jr

All Theses

Constraining parameters that govern variably saturated flow is important for applications ranging from quantifying water availability for ecosystems to constraining recharge rates and contaminant fluxes to groundwater. In this study I explore the effectiveness of sequential versus integrated data fusion for estimating unsaturated flow parameters using ground penetrating radar (GPR) data. In Sequential Data Fusion (SDF), geophysical imaging is used to create a map of the geophysical properties of the subsurface. These properties are then transformed to hydrologic properties that can be used to constrain an independent hydrologic inverse problem. In contrast, Integrated Data Fusion (IDF) uses the geophysical data …