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Elk Hunting On Turnbull National Wildlife Refuge: Impacts On Elk Movement And Aspen Regeneration, Christopher E. Dwight Jan 2012

Elk Hunting On Turnbull National Wildlife Refuge: Impacts On Elk Movement And Aspen Regeneration, Christopher E. Dwight

EWU Masters Thesis Collection

"In the arid West, quaking aspen (Populus tremuloides) cover less than 10% of the forest landscape, yet support a disproportionate diversity of native plants and animals. When elk (Cervus elaphus) become overabundant, browsing prevents aspen regeneration, reduces survival, and consequently impacts local biodiversity. Given this, Turnbull National Wildlife Refuge (TNWR) initiated a limited annual elk hunt beginning in fall 2010. This study examines whether the hunt affected elk usage of the refuge and, indirectly, aspen growth and regeneration. To determine elk movement and usage of the refuge prior to and following the elk hunt, 34 radio-collared cow elk were monitored …


Age Composition And Distribution Of Red Drum (Sciaenops Ocellatus) In Offshore Waters Of The North Central Gulf Of Mexico: An Evaluation Of A Stock Under A Federal Harvest Moratorium, Sean P. Powers, Crystal Hightower, J. Marcus Drymon, Matthew W. Johnson Jan 2012

Age Composition And Distribution Of Red Drum (Sciaenops Ocellatus) In Offshore Waters Of The North Central Gulf Of Mexico: An Evaluation Of A Stock Under A Federal Harvest Moratorium, Sean P. Powers, Crystal Hightower, J. Marcus Drymon, Matthew W. Johnson

University Faculty and Staff Publications

Because of a lack of fishery- dependent data, assessment of the recovery of fish stocks that undergo the most aggressive form of management, namely harvest moratoriums, remains a challenge. Large schools of red drum (Sclaenops ocellatus) were common along the northern Gulf of Mexico until the late 1980s when increased fishing effort quickly depleted the stock. After 24 years of harvest moratorium on red drum in federal waters, the stock is in need of reassessment; however, fishery dependent data are not available in federal waters and fishery-independent data are limited. We document the distribution, age composition, growth, and condition of …


Gonadal Abnormalities In Frogs (Lithobates Spp.) Collected From Managed Wetlands In An Agricultural Region Of Nebraska, Usa, Diana M. Papoulias, Matt S. Schwarz, Lourdes Mena Jan 2012

Gonadal Abnormalities In Frogs (Lithobates Spp.) Collected From Managed Wetlands In An Agricultural Region Of Nebraska, Usa, Diana M. Papoulias, Matt S. Schwarz, Lourdes Mena

United States Geological Survey: Staff Publications

Nebraska’s Rainwater Basin (RWB) provides important wetland habitat for North American migratory birds. Concern exists that pesticide and nutrient runoff from surrounding row-crops enters wetlands degrading water quality and adversely affecting birds and wildlife. Frogs may be especially vulnerable. Plains leopard (Lithobates blairi) metamorphs from RWB wetlands with varying concentrations of pesticides were evaluated for a suite of biomarkers of exposure to endocrine active chemicals. Froglets had ovarian dysgenesis, high rates of testicular oocytes, and female-biased sex ratios however, there was no clear statistical association between pesticide concentrations and biomarkers. Data interpretation was hindered because timing and duration …


Wildlife Toxicology: Environmental Contaminants And Their National And International Regulation, K. Christiana Grim, Anne Fairbrother, Barnett A. Rattner Jan 2012

Wildlife Toxicology: Environmental Contaminants And Their National And International Regulation, K. Christiana Grim, Anne Fairbrother, Barnett A. Rattner

United States Geological Survey: Staff Publications

Wildlife toxicology is the study of potentially harmful effects of toxic agents in wild animals, focusing on amphibians, reptiles, birds, and mammals. Fish and aquatic invertebrates are not usually included as part of wildlife toxicology since they fall within the field of aquatic toxicology, but collectively both disciplines often provide inSight into one another and both are integral parts of ecotoxicology (Hoffman et al. 2003). It entails monitoring, hypothesis testing, forensics, and risk assessment; encompasses molecular through ecosystem responses and various research venues (laboratory, mesocosm, field); and has been shaped by chemical use and misuse, ecological mishaps, and biomedical research. …


Development And Application Of Methods Used To Source Prehistoric Southwestern Maize: A Review, Larry Benson Jan 2012

Development And Application Of Methods Used To Source Prehistoric Southwestern Maize: A Review, Larry Benson

United States Geological Survey: Staff Publications

Archaeological cobs free of mineral contaminants should be used to source the soils in which they were grown. Mineral contaminants often contain much higher concentrations of metals than vegetal materials and can alter a cob’s apparent metal and heavy-isotope content. Cleaning a cob via immersion in an acid solution for more than a few minutes will result in the incongruent and sometimes complete leaching of metals, including strontium (Sr), from the cob. When using 87Sr/86Sr to determine the location of potential agriculture fields, it is best to either integrate several depth-integrated soil samples or to integrate several …


Spatially Explicit Models For Inference About Density In Unmarked Or Partially Marked Populations, Richard B. Chandler, J. Andrew Royle Jan 2012

Spatially Explicit Models For Inference About Density In Unmarked Or Partially Marked Populations, Richard B. Chandler, J. Andrew Royle

United States Geological Survey: Staff Publications

Recently developed spatial capture-recapture (SCR) models represent a major advance over traditional capture-recapture (CR) models because they yield explicit estimates of animal density instead of population size within an unknown area. Futhermore, unlike nonspatial CR methods, SCR models account for heterogeneity in capture probability arising from the juxtaposition of animal activity centers and sample locations. Although the utility of SCR methods is gaining recognition, the requirement that all individuals can be uniquely identified exludes their use in many contexts. In this paper, we develop models for situations in which individual recognition is not possible, thereby allowing SCR concepts to be …


Profitable Farms And Woodlands: A Practical Guide In Agroforestry For Landowners, Farmers And Ranchers, J. O. Idassi Jan 2012

Profitable Farms And Woodlands: A Practical Guide In Agroforestry For Landowners, Farmers And Ranchers, J. O. Idassi

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

This handbook is part of an interdisciplinary, interinstitutional and comprehensive effort to develop a practical guide to assist underserved and limited resource small farmers and woodland owners to adopt best management technologies in agroforestry. Funding for this effort was provided through the USDA National Agroforestry Center (NAC) from the US Forest Service and the Natural Resources Conservation Service (NRCS) under cooperative agreement number 68-7482-7-361 with Tennessee State University, Cooperative Extension Program and the 1890/1862 Agroforestry Team.

This guide was prepared by an agroforestry team of research and extension specialists from the 1862 and 1890 Land Grant Universities in collaboration with …


Agroforestry: Accounting For Windbreak's Climate Change Contributions, Michele Schoeneberger, Jim Brandle, Xinhua Zhou, John Kort, Tom Sauer Jan 2012

Agroforestry: Accounting For Windbreak's Climate Change Contributions, Michele Schoeneberger, Jim Brandle, Xinhua Zhou, John Kort, Tom Sauer

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

No abstract provided.


Gene Transcription In Sea Otters (Enhydra Lutris); Development Of A Diagnostic Tool For Sea Otter And Ecosystem Health, Lizabeth Bowen, A. Keith Miles, Michael Murray, Martin Haulena, Judy Tuttle, William Van Bonn, Lance Adams, James L. Bodkin, Brenda Ballachey, James A. Estes, M. Tim Tinker, Robin Keister, Jeffrey L. Stott Jan 2012

Gene Transcription In Sea Otters (Enhydra Lutris); Development Of A Diagnostic Tool For Sea Otter And Ecosystem Health, Lizabeth Bowen, A. Keith Miles, Michael Murray, Martin Haulena, Judy Tuttle, William Van Bonn, Lance Adams, James L. Bodkin, Brenda Ballachey, James A. Estes, M. Tim Tinker, Robin Keister, Jeffrey L. Stott

United States Geological Survey: Staff Publications

Gene transcription analysis for diagnosing or monitoring wildlife health requires the ability to distinguish pathophysiological change from natural variation. Herein, we describe methodology for the development of quantitative real-time polymerase chain reaction (qPCR) assays to measure differential transcript levels of multiple immune function genes in the sea otter (Enhydra lutris); sea otter-specific qPCR primer sequences for the genes of interest are defined. We establish a ‘reference’ range of transcripts for each gene in a group of clinically healthy captive and free-ranging sea otters. The 10 genes of interest represent multiple physiological systems that play a role in immuno-modulation, …


Establishing Winter Origins Of Migrating Lesser Snow Geese Using Stable Isotopes, Viviane Hénaux, Larkin A. Powell, Mark P. Vrtiska, Keith A. Hobson Jan 2012

Establishing Winter Origins Of Migrating Lesser Snow Geese Using Stable Isotopes, Viviane Hénaux, Larkin A. Powell, Mark P. Vrtiska, Keith A. Hobson

School of Natural Resources: Faculty Publications

Increases in Snow Goose (Chen caerulescens) populations and large-scale habitat changes in North America have contributed to the concentration of migratory waterfowl on fewer wetlands, reducing resource availability, and enhancing risks of disease transmission. Predicting wintering locations of migratory individuals is critical to guide wildlife population management and habitat restoration. We used stable carbon (δ13C), nitrogen (δ 15N), and hydrogen (δ2H) isotope ratios in muscle tissue of wintering Snow Geese to discriminate four major wintering areas, the Playa Lake Region, Texas Gulf Coast, Louisiana Gulf Coast, and Arkansas, and infer the wintering locations …


Agriculture And Food In Crisis: Conflict, Resistance, And Renewal [Book Review], Charles A. Francis Jan 2012

Agriculture And Food In Crisis: Conflict, Resistance, And Renewal [Book Review], Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

Edited by Fred Magdoff and Brian Tokar. 2010. Monthly Review Press, New York, New York, United States. 348 p. Paperback, cloth US$ 75.00, paper US$ 18.95, ISBN-13 978-1-58367-226-6.

That doubling of food production over the next four decades will be needed to adequately nourish our human population is not news, but the incredible steps essential to achieve that goal and their political and social implications are less well reported. In this series of 16 essays edited by Fred Magdoff and Brian Tokar, several thoughtful specialists in global food issues explore the historical, biological, economic, energy, political and social dimensions of …


Cover Crop Mixtures For The Western Corn Belt: Opportunities For Increased Productivity And Stability, Samuel E. Wortman, Charles A. Francis, John L. Lindquist Jan 2012

Cover Crop Mixtures For The Western Corn Belt: Opportunities For Increased Productivity And Stability, Samuel E. Wortman, Charles A. Francis, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

Achieving agronomic and environmental benefits associated with cover crops oft en depends on reliable establishment of a highly productive cover crop community. The objective of this study was to determine if cover crop mixtures can increase productivity and stability compared to single species cover crops, and to identify those components most active in contributing to or detracting from mixture productivity. A rainfed field experiment was conducted near Mead, Nebraska, United States, in 2010 and 2011. Eight individual cover crop species (in either the Brassicaceae [mustard] or Fabaceae [legume] family) and four mixtures of these species (two, four, six, and eight …


Novel Lineages Of Prochlorococcus And Synechococcus In The Global Oceans, Sijun Huang, Steven W. Wilhelm, H. Rodger Harvey, Karen Taylor, Nianzhi Jiao, Feng Chen Jan 2012

Novel Lineages Of Prochlorococcus And Synechococcus In The Global Oceans, Sijun Huang, Steven W. Wilhelm, H. Rodger Harvey, Karen Taylor, Nianzhi Jiao, Feng Chen

OES Faculty Publications

Picocyanobacteria represented by Prochlorococcus and Synechococcus have an important role in oceanic carbon fixation and nutrient cycling. In this study, we compared the community composition of picocyanobacteria from diverse marine ecosystems ranging from estuary to open oceans, tropical to polar oceans and surface to deep water, based on the sequences of 16S-23S rRNA internal transcribed spacer (ITS). A total of 1339 ITS sequences recovered from 20 samples unveiled diverse and several previously unknown clades of Prochlorococcus and Synechococcus. Six high-light (HL)-adapted Prochlorococcus clades were identified, among which clade HLVI had not been described previously. Prochlorococcus clades HLIII, HLIV and …


Physiochemical Characteristics Contributing To The Cytotoxicity Of Transition Metal Oxides, Chi-Heng Wu Jan 2012

Physiochemical Characteristics Contributing To The Cytotoxicity Of Transition Metal Oxides, Chi-Heng Wu

Masters Theses

"In the past ten years nanotechnology has not only evolved to play a prominent role in our economy but also increased the concern over potential adverse effects caused by nanomaterials to human health and the environment. Nanotoxicity is to understand the nature and origin of the toxicity imposed by nanomaterials. Studies from our laboratory have shown that nanoparticle induces oxidative stress, perturbs calcium homeostasis, alter gene expression, and produces pro-inflammatory responses. We also identified a trend of toxicity: TiO₂ < Cr₂O₃ < Fe₂O₃ < Mn₂O₃ < NiO < ZnO < CuO. We then asked a question: what are physiochemical factors of transition metal nanoparticles that contributed to this increasing cytotoxicity. In this thesis I investigated the correlation between physicochemical properties and toxicity of the transition metal oxides in the 4th Period of the Periodic Table of Elements. Particle size, BET surface area, point of zero charge, metal dissolution, and degree of surface adsorption of transition metal oxide nanoparticles were measured. There were no increasing trends in both particle size and specific surface area. The point of zero charge showed an increasing trend as TiO₂ < Cr₂O₃ < Fe₂O₃ < NiO < CuO = ZnO < Mn₂O₃. The number of available binding sites of nanoparticle showed an increasing trend as Cr₂O₃ > ZnO > CuO > NiO > Fe₂O₃ > Mn₂O₃ > TiO₂. The degree of adsorption on the surface of nanoparticles showed an increasing trend with atomic …


Effectiveness Of Grass Filters In Reducing Phosphorus And Sediment Runoff, Ahmed Al-Wadaey, Charles S. Wortmann, Thomas G. Franti, Charles A. Shapiro, Dean E. Eisenhauer Jan 2012

Effectiveness Of Grass Filters In Reducing Phosphorus And Sediment Runoff, Ahmed Al-Wadaey, Charles S. Wortmann, Thomas G. Franti, Charles A. Shapiro, Dean E. Eisenhauer

Department of Agronomy and Horticulture: Faculty Publications

Surface water contamination can often be reduced by passing runoff water through perennial grass filters. Research was conducted in 2006 to 2008 to evaluate the size of cool season grass filters consisting primarily of tall fescue (Festuca arundinacea Schreb) with some orchard grass (Dactylis glomerata L.) relative to drainage area size in reducing runoff sediment and phosphorus (P). The soil was Pohocco silt loam Typic Eutrochrepts with a median slope of 5.5%. The grass filters occupying 1.1 and 4.3% of the plot area were compared with no filter with four replications. The filters were planted in the V-shaped …


Impact Of Vegetation On Land-Atmosphere Coupling Strength And Its Implication For Desertification Mitigation Over East Asia, Boksoon Myoung, Yong-Sang Choi, Suk-Jin Choi, Seon Ki Park Jan 2012

Impact Of Vegetation On Land-Atmosphere Coupling Strength And Its Implication For Desertification Mitigation Over East Asia, Boksoon Myoung, Yong-Sang Choi, Suk-Jin Choi, Seon Ki Park

Mathematics, Physics, and Computer Science Faculty Articles and Research

Desertification of the East Asian drylands and the consequent dust transport have been serious concerns for adjacent Asian countries as well as the western United States. Tree planting has been considered one applicable strategy to mitigate the desertification. However, the desired effect of the tree planting would not be brought to fruition unless the newly planted trees change the coupling characteristics between the land and the atmosphere. Based on this perception, we attempt to clarify the effects of vegetation on the coupling strength between the atmosphere and land surface, and we suggest the most efficient areas of tree planting for …


The Role Of A Generalized Ultraviolet Cue For Blackbird Food Selection, Scott J. Werner, Shelagh K. Tupper, James C. Carlson, Susan E. Pettit, Jeremy W. Ellis, George M. Linz Jan 2012

The Role Of A Generalized Ultraviolet Cue For Blackbird Food Selection, Scott J. Werner, Shelagh K. Tupper, James C. Carlson, Susan E. Pettit, Jeremy W. Ellis, George M. Linz

United States Department of Agriculture Wildlife Services: Staff Publications

Birds utilize ultraviolet (UV) wavelengths for plumage signaling and sexual selection. Ultraviolet cues may also be used for the process of avian food selection. The aim of our study was to investigate whether a UV cue and a postingestive repellent can be used to condition food avoidance in red-winged blackbirds (Agelaius phoeniceus). We found that birds conditioned with an UV-absorbent, postingestive repellent subsequently avoided UV-absorbent food. Thus, the UV-absorbent cue (coupled with 0–20% of the conditioned repellent concentration) was used to maintain avoidance for up to 18 days post-conditioning. Similarly, birds conditioned with the UV-absorbent, postingestive repellent subsequently …


Evaluation Of Elevated Bait Trays For Attracting Blackbirds (Icteridae) In Central North Dakota, George M. Linz, Jamison B. Winter, William J. Bleier Jan 2012

Evaluation Of Elevated Bait Trays For Attracting Blackbirds (Icteridae) In Central North Dakota, George M. Linz, Jamison B. Winter, William J. Bleier

United States Department of Agriculture Wildlife Services: Staff Publications

Sunflower (Helianthus annuus L.) became an economically important crop in North Dakota in the 1970s, providing a major source of food for post-breeding blackbirds (Icteridae). Reducing local blackbird populations with rice grains treated with an avicide is one proposed alternative for reducing sunflower damage. In fall 2007 and 2008, we evaluated the idea of attracting blackbirds to rice-baited trays attached to wire cages supplied with live blackbirds. During our observations (1011 h), we saw 3888 birds, consisting of 25 species and 12 families, on the bait trays. Blackbirds made up 90.4% of the bird observations, whereas sparrows (Emberizidae) made …


Long-Term Responses Of Phalaris Arundinacea And Columbia River Bottomland Vegetation To Managed Flooding, Tina Schantz Farrelly Jan 2012

Long-Term Responses Of Phalaris Arundinacea And Columbia River Bottomland Vegetation To Managed Flooding, Tina Schantz Farrelly

Dissertations and Theses

I sought to determine the effect of managed flooding on Phalaris arundinacea L. and other plant species distributions in a large wetland complex, Smith and Bybee Wetlands (SBW), in northwestern Oregon. Altered hydrology has reduced historically high spring flow and prematurely initiated the historic summer drying period at SBW. This alteration has increased the coverage of invasive plants (e.g., P. arundinacea) causing a decrease in native plant cover and thus degrading ecological functions. SBW managers installed a water control structure (WCS) between SBW and the Columbia Slough/River system to impound winter rainfall and thus approximate the ecological benefits that natural …


Understanding Sand Mining On The Maha Oya: The Conflict Between Economic And Environmental Survival, Meredith Corea Talbert Jan 2012

Understanding Sand Mining On The Maha Oya: The Conflict Between Economic And Environmental Survival, Meredith Corea Talbert

Dissertations and Theses

River sand mining from the Maha Oya is the main source of income and a force that drives economic activity for residents along the river. This study takes place in Sri Lanka, there are three villages included in this project: Jambugaswatte, Janituspuraya and Thoppuwa. In Sri Lanka, sand serves as the main building material. It is used to make bricks, tiles, asphalt and concrete, therefore demanding a high market value. However, the over-extraction of sand comes along with significant environmental problems. These communities depend on the river in many ways and the health of the river directly corresponds to the …


A Systems Approach To Ecological Economic Models Developed Progressively In Three Interwoven Articles, Takuro Uehara Jan 2012

A Systems Approach To Ecological Economic Models Developed Progressively In Three Interwoven Articles, Takuro Uehara

Dissertations and Theses

My dissertation develops and analyzes ecological economic models to study the complex dynamics of an ecological economic system (EES) and investigate various conditions and measures which can sustain a developing economy over the long term in view of resilience and sustainability. Because of the intrinsic complexity of the system, I take a systems approach, using economics as the foundation for the basic structure of an ecological economic model, and system dynamics as the method to build and analyze such a complex ecological economic model. Throughout my dissertation, the model developed by Brander and Taylor (1998) is adopted as a baseline …


Applied Evaluation For Life Cycle Impact Assessment Methodologies In The Medical Industry, Aaron Arturo Martinez Jan 2012

Applied Evaluation For Life Cycle Impact Assessment Methodologies In The Medical Industry, Aaron Arturo Martinez

Open Access Theses & Dissertations

In the present thesis, a comparative evaluation using different Life Cycle Impact Assessment (LCIA) Methodologies is presented; the study is performed considering the LCIA of ChloraPrep 26 mL Hi-Lite Applicator produced in a local manufacturing company. The focus of the research is to analyze the different aspects such as: characterization, classification and normalization; that each of the LCIA methodologies evaluate and are used for a policy regulations and sustainable development. The evaluation will determine which aspects could be used depending on the Life Cycle Inventory, since limited information is available if not using softwares, such as SimaPro or GaBi, to …


Growing Cities Depend On Ecosystem Services, David E. Ervin, Darrell Brown, Heejun Chang, Veronica Dujon, Elise F. Granek, Vivek Shandas, J. Alan Yeakley Jan 2012

Growing Cities Depend On Ecosystem Services, David E. Ervin, Darrell Brown, Heejun Chang, Veronica Dujon, Elise F. Granek, Vivek Shandas, J. Alan Yeakley

Geography Faculty Publications and Presentations

Many studies have documented the growing fragility of a majority of the globe's ecosystems. Policymakers and resource managers often frame such ecosystem challenges as primarily about protecting natural systems in rural areas. However, that conception misses a key part of the story: the rapid growth of urbanizing areas. Home to more than 50 percent of the world's human population for the first time in modern history, urbanizing regions concentrate pressure on ecosystem services, which are necessary to sustain healthy urban living conditions and vibrant commerce. This dramatic urbanization presents both challenges and opportunities for novel ecosystem services management. A transdisciplinary …


Microelement Localization In Leaves Of Populus Spp. And Tolerance Mechanisms To Boron-Salt Toxicity, Daniel Arriaga Jan 2012

Microelement Localization In Leaves Of Populus Spp. And Tolerance Mechanisms To Boron-Salt Toxicity, Daniel Arriaga

Open Access Theses & Dissertations

Phytoremediation has been proposed as a low-cost, environmentally friendly alternative to clean highly contaminated sites. Phytoremediation using trees offer the advantage of metal immobilization (phytostabilization), high hydraulic pumping pressures, produce large plant biomass, absorption of total dissolved salts within their tissue, long life spans, less frequent irrigation and, a massive root system that helps soil attachment. Hybrid poplar varieties are long-lived, perennial, fast growing, and produce a large amount of foliage to harvest. Boron is an essential micronutrient for plants. Certain locations, such as California and Turkey, have suffered from high boron efflux from irrigation waters. It has been identified …


Sustainable Wastewater Management For Paso Del Norte Border Communities, Mariana Chew Jan 2012

Sustainable Wastewater Management For Paso Del Norte Border Communities, Mariana Chew

Open Access Theses & Dissertations

At the binational level, there is no enforceable formal or informal agreement for approval of a water or wastewater discharge from the United States or Mexico. The communities along the U.S.-Mexico border are included in the cooperative activities of: (1) U.S. Environmental Protection Agency (EPA) Region VI, (2) Mexico Secretarí­a de Medio Ambiente y Recursos Naturales (SEMARNAT), (3) the binational Border Environment Cooperation Commission (BECC) and Comisión de Cooperación Ecológica Fronteriza (COCEF), (4) the binational North American Development Bank (NADBANK) and Banco de Desarrollo de América del Norte (BDAN), and (5) the binational International Boundary and Water Commission (IBWC) and …


The Impact Of Solar Radiation On The Distribution Of The Red Imported Fire Ant, Solenopsis Invicta (Hymenoptera: Formicidae), Audrey Marie Hernando Jan 2012

The Impact Of Solar Radiation On The Distribution Of The Red Imported Fire Ant, Solenopsis Invicta (Hymenoptera: Formicidae), Audrey Marie Hernando

Open Access Theses & Dissertations

This dissertation investigates the role of solar radiation on Solenopsis invicta, the red imported fire ant. This ant is considered a serious invasive pest in the southern United States. Four Texas cities where fire ants are found were studied: San Antonio, Corpus Christi, Wichita Falls, and the outlier, Lubbock. Shade angles were measured in eight compass directions within plots located along eight transect directions around buildings. Using the shade angle, solar radiation for different times of day and seasons were calculated. All of the cities were on the same precipitation isocline with the exception of Lubbock, Texas. The number of …


Low Energy Disruption Of Lipid Containing Biomass, Joaquin Rodriguez Jan 2012

Low Energy Disruption Of Lipid Containing Biomass, Joaquin Rodriguez

Open Access Theses & Dissertations

Lipid containing biomass from microalgae has received recent research interest as a renewable and sustainable feedstock for biofuel production. Algae is known to offer as much as 30 times the energy density than corn based ethanol, the current world standard for biomass based liquid transportation fuels. The development of large scale systems and methods of extracting lipids from microalgae is still in the early stages of development and significant increases in efficiency and reduction in costs are necessary to substantiate algae as a feasible alternative source of fuel. Traditional conversion of algae feedstock into a refineable feedstock for biofuel can …


Propagation Of Interval And Probabilistic Uncertainty In Cyberinfrastructure-Related Data Processing And Data Fusion, Christian Servin Jan 2012

Propagation Of Interval And Probabilistic Uncertainty In Cyberinfrastructure-Related Data Processing And Data Fusion, Christian Servin

Open Access Theses & Dissertations

Data uncertainty affects the results of data processing. So, it is necessary to find out how the data uncertainty propagates into the uncertainty of the results of data processing.

This problem is especially important when cyberinfrastructure enables us to process large amounts of heterogeneous data.

In the ideal world, we should have an accurate description of data

uncertainty, and well-justified efficient algorithms to propagate this uncertainty. In practice, we are often not yet in this ideal situation:

the description of uncertainty is often only approximate, and the algorithms for uncertainty propagation are often not well-justified and not very computationally efficient. …


Biological Effects Of Copper On Prosopis Pubescens (Screw Bean Mesquite), Marian Nicte Zappala Jan 2012

Biological Effects Of Copper On Prosopis Pubescens (Screw Bean Mesquite), Marian Nicte Zappala

Open Access Theses & Dissertations

Phytoremediation is an emerging technology for cleaning industrial and urban contamination (Peuke and Rennenberg, 2005). Many factors including germination rate, biomass changes, biochemical changes, and nutrient changes must be determined in order to utilize a plant for phytoremediation. Our results showed that Prosopis pubescens (Screw bean mesquite) is a hyperaccumulator of copper from copper sulfate and a feasible option to remediate fields with up to 200 ppm of copper sulfate.

Screw bean mesquite seeds are viable even after 30 years of storage. Both copper sulfate and copper nitrate decreased the germination rate of screw bean mesquite seeds. In soil grown …


Scale And Justice In Water Allocation, Marian J. Patrick Jan 2012

Scale And Justice In Water Allocation, Marian J. Patrick

Theses: Doctorates and Masters

Water allocation is a fundamental part of water resources management. Water allocation is often a contested process because it involves multiple uses and users of water. Issues of justice arise when resources are, or are perceived to be, in short supply. When water is allocated the rules for the distribution of the resource may result in just outcomes for some stakeholders but may create injustices for other stakeholders. Issues of scale thus form an important component of water allocation. This thesis draws from an amalgam of ideas on justice, scale and water management and aims to present a conceptual framework …