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Deposition Patterns And Rates Of Mining-Contaminated Sediment Within A Sedimentation Basin System, S.E. Missouri, Joshua Carl Voss

Graduate Theses/Dissertations

Flooding events exert a dominant control over the deposition and formation of floodplains. The rate at which floodplains form depends on flood magnitude, frequency, and duration, and associated sediment transport capacity and supply. While it is known that sediment in the Big River is contaminated from historical mining, little is known about the patterns and rates of deposition on floodplains, especially those that have been modified for remediation purposes. The goal of this study was to evaluate the influence of flood characteristics and topography on contemporary deposition patterns and rates in a sedimentation basin system located within a floodplain along …

Competition Amplifies Drought Stress In Forests Across Broad Climatic And Compositional Gradients, Kelly E. Gleason, John B. Bradford, Alessandra Bottero, Anthony W. D'Amato, Shawn Fraver, Brian J. Palik, Michael A. Battaglia, Louis Iverson, Laura Kenefic, Christel C. Kern

Environmental Science and Management Faculty Publications and Presentations

Forests around the world are experiencing increasingly severe droughts and elevated competitive intensity due to increased tree density. However, the influence of interactions between drought and competition on forest growth remains poorly understood. Using a unique dataset of stand-scale dendrochronology sampled from 6405 trees, we quantified how annual growth of entire tree populations responds to drought and competition in eight, long-term (multi-decadal), experiments with replicated levels of density (e.g., competitive intensity) arrayed across a broad climatic and compositional gradient. Forest growth (cumulative individual tree growth within a stand) declined during drought, especially during more severe drought in drier climates. Forest …

Land Use As An Indicator Of Stream Habitat Quality In Salt Creek, Adam Brown

Department of Environmental Studies: Undergraduate Student Theses

This study sought to quantify land use types in Lancaster County and identify which, if any, environmental parameters were significantly influencing fish and invertebrate distribution in the Salt Creek basin. Historical sampling data were obtained from the Nebraska Department of Environmental Quality. Watershed land cover maps were created and the percentages of urban/developed, forested, row crop, and grassland use were calculated. This data was combined with NDEQ water quality parameter, fish, and invertebrate sampling data to conduct nonmetric multidimensional scaling. This analysis did not provide significant conclusions about the driving force of fish and invertebrate distribution in this region because …

Ord River Irrigation Area Stage 2: M2 Supply Channel - Compliance Assessment Report 2016 - Statement 938, Stratagen

Reports

The WA Minister for State Development (the proponent) has approval to develop land for irrigated agriculture across the Weaber, Keep River and Knox Creek Plains, located north-northeast of Kununurra in the eastern Kimberley region of WA and extends to the Keep River estuary in the Northern Territory. The area of development (M2 Area) is immediately northeast of the existing Ord River Irrigation Area (ORIA), with proposed development representing the second stage of the ORIA scheme. It comprises approximately 76 000 ha (including Buffer Areas) and a key part of the development is main irrigation channel (the ‘M2 channel’), that extends …

Risks Associated With Harvesting And Human Consumption Of Two Turtle Species In New Jersey, Natalie R. Sherwood

Theses, Dissertations and Culminating Projects

Snapping turtles and diamondback terrapins have unique life characteristics, making their populations’ survivorship heavily dependent upon the turtles that reach sexual maturity, limiting the harvest potential of turtles and making them vulnerable to exploitation. Therefore, this research tests mercury concentrations in diamondback terrapins and snapping turtles to determine if turtle meat should require human consumption advisories, and examines transport of mercury through the snapping turtle food web by testing prey items for mercury burden and mapping food webs using stable isotope composition.

Consumption of New Jersey diamondback terrapins and snapping turtles pose a health risk. 25% of Cape May and …

Emphasizing Colonization In Modern Environmental And Women’S Activist Movements In India And The Future Of Ecofeminist Movements For Creating A More Just And Sustainable Future, Alea M. Tveit

Honors Theses

This research discusses the extent of colonial acknowledgement in modern women’s rights and environmental movements in India. British colonization profoundly altered the ecological landscape and social norms of the societies it affected while leaving behind institutional structures that encouraged and perpetuated discrimination, oppression, and environmental degradation. In the case of India, I illustrate pre-colonial norms surrounding environmental stewardship and women’s rights and compare it to post-colonial ideology to make a connection of modern human rights and environmental problems to a colonial past. Today’s popular environmental and women’s activist movements are analyzed to determine if colonial acknowledgment or a decolonial framework …

Influence Of Stream Permanence, Predation, And Invasive Species On Crayfish In The Ozark Highlands With An Emphasis On Species Of Greatest Conservation Need (Orconectes Marchandi, Orconectes Eupunctus And Cambarus Hubbsi), Allyson Noelle Yarra

Graduate Theses and Dissertations

Due to the ecological importance of crayfish and the increasing vulnerability of freshwater systems due to habitat loss, invasive species, and hydrologic alteration, understanding crayfish-environment relationships is crucial in the context of aquatic species conservation. I sought to examine the influence of hydrologic variation among intermittent and permanent streams on crayfish occupancy, abundance, predation risk, and potential vulnerability to invasive species effects. I conducted crayfish and environmental data sampling during two consecutive summers across 20 Ozark streams of differing permanence levels (10 intermittent, 10 permanent). In these same streams, I conducted fish and scat surveys over the course of four …

A Multi-Millennial Drought Reconstruction For West-Central New Mexico Using Rocky Mountain Juniper (Juniperus Scopulorum, Sarg.), Joshua S. Oliver

Master's Theses

A new multi-millennial tree-ring record from living and remnant Rocky Mountain juniper (Juniperus scopulorum, Sarg.) wood from Candelaria in west-central New Mexico is used to determine the temporal and spatial variability of scPDSI over the past two millennia (B.C. 492 to A.D. 2014). Our record indicates extreme drought events found within other hydroclimatic proxy records in the Colorado Plateau region spanning the time period (16^th century and 2^nd century megadroughts). By ranking the extreme drought events by magnitude, duration, intensity, and overall score, the most extreme drought events of this record are compared to drought events …

Evaluation Of The Correlation Between The Oxidation Reduction Potential And Free Chlorine Residual For Different Chlorine Sources Used In Poultry Drinking Water Sanitation, Samantha Renee Cox

Graduate Theses and Dissertations

A critical component in commercial poultry production is to ensure birds are provided clean, quality water. Multiple disinfectants can be utilized to optimize a good water quality program. The goal of these water disinfectants is to greatly reduce or eliminate the presence of all bacteria. In recent years, the oxidation-reduction potential (ORP) meter has been a tool utilized by the poultry industry to monitor chlorine efficacy in drinking water. An ORP reading of 650-750 millivolts (mV) has become the industry standard for assuring an acceptable sanitizing residual of free chlorine is present for controlling microbial contamination regardless of the actual …

Ecological Importance Of Invader Source Population And Disturbance In Aquatic Invasions, Nicole Elizabeth Graham

Graduate Theses and Dissertations

Invasive species are a global problem and their effects on recipient ecosystems may be mediated by disturbance and intraspecific variation. Crayfish can substantially influence stream structure and function, and invasive crayfish often have differential impacts than native crayfish in aquatic ecosystems. Since species traits often vary across a distribution, it is possible that invasive crayfish from different source populations may have distinct impacts on recipient ecosystem structure and function. In the Ozark Highlands of Arkansas and Missouri, USA, invasive O. neglectus (the Ringed Crayfish) may be leading to the displacement of native O. eupunctus (the Coldwater Crayfish). The objective of …

Remotely Sensed Heat : Variation And Change In Surface Urban Heat Islands In A Temperate Eco-Region Of The United States., Jeremy Sandifer

Electronic Theses and Dissertations

Urban heat island (UHI) is a term used to describe increased surface and atmospheric temperatures in an urban core relative to surrounding non-urbanized areas. To examine the variability introduced into derived estimates of the surface UHI, this study constructs and compares multiple remotely sensed indicators of the surface UHI for major metropolitan cities of a temperate eco-region of the United States. The Moderate Resolution Imaging Spectroradiometer (MODIS) 8-day, 500-meter product (MOD11A2) is the source data used to calculate six different RS-derived UHI indicators for the year 2002 to 2012. The different SUHI indicators are evaluated using the Spearmans Rho rank-order …

Heterogeneity Of Avian Breeding Habitat On Grazing Lands Of The Northern Great Plains, Maggi S. Sliwinski

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

Native rangelands in the Great Plains are largely privately owned and used for beef production. Vegetation heterogeneity is important for maintaining biodiversity, but private land may be more homogenous than desired. My research had two components: 1) to examine whether a variety of grazing strategies created vegetation heterogeneity in a large, intact rangeland, and 2) to understand beef producers’ attitudes about vegetation heterogeneity.

First, I sampled vegetation structure, composition, and bird abundance at multiple plots on eleven management units in Cherry County, Nebraska. Units were managed with commonly used grazing strategies (e.g., short-duration grazing and season-long continuous grazing). I examined …

Thermal And Developmental Ecology Of Pupfish, Cyprinodon, Alexander Jones

UNLV Theses, Dissertations, Professional Papers, and Capstones

Pupfish from the genus Cyprinodon are among the most endangered groups of fishes on the planet, with nearly 40% of species being threatened with extinction. These pupfishes are often assumed to be the most temperature tolerant of all fish, coping with temperatures as low as 0 °C and as high as 44 °C. However, conflicting data exist and certain measures of thermal tolerance are not markedly higher in pupfish compared to common game fish. Pupfish egg production and growth has been known to be hampered at temperatures well below what they apparently experience in nature. I addressed why eggs fail …

Living On The Edge: Assessing The Effects Of Catastrophic Fire On Plants Utilized By Two Endemic Subspecies Of Spring Mountains Butterflies, Charles Ryan Herrmann

UNLV Theses, Dissertations, Professional Papers, and Capstones

In the past few decades there has been an increase in catastrophic, high-intensity, large-scale wildfires globally due to the combination of climate warming with more than a century of fire suppression policy. One region that has been drastically affected is the Western United States, as there has been an increase in ‘mega-fires’ in the past few decades. The 2013 Carpenter 1 Fire in the Spring Mountains, Nevada was the largest fire in recorded history in these mountains, spreading out over 11,137 hectares. Catastrophic fire like the Carpenter 1 Fire can have potentially devastating effects on endemic species inhabiting refugia on …

Evaluation Of A Fluorescence Method For Quantifying Bioaerosol Concentrations On Air Quality Filter Samples, Rachel Kolberg

UNLV Theses, Dissertations, Professional Papers, and Capstones

Airborne particulate matter (PM) in outdoor environments contains many components that cause adverse human health effects. The size of the particulates determine in what manner the particles would bypass the body’s defense mechanisms to enter the respiratory system and is directly related to their health impacts. Currently the United States Environmental Protection Agency is enforcing the National Ambient Air Quality Standards (NAAQS) to regulate the annual and 24-hour average concentrations of PM2.5 and PM10 in the air. PM2.5 are fine particles with aerodynamic diameter <2.5μm, small enough to reach the deepest parts of the bronchi and lungs. PM10 include PM2.5 and larger particles with aerodynamic diameter of 2.5-10μm. Both PM2.5 and PM10 contain multiple components from multiple sources. Bioaerosols are an important component of PM, but there is limited knowledge about how bioaerosols contribute to PM2.5 and PM10 concentrations. There is also a lack of research about the incidence and prevalence of disease caused by bioaerosols and about the limits of exposure to bioaerosol particulates. The main barrier to assess bioaerosol concentrations and health-related effects is the absence of quick and inexpensive methodology for quantifying bioaerosols. This study explored the feasibility of using fluorescence microscopy to quickly quantify bioaerosols in PM2.5 and PM10 collected on polycarbonate filters. Bioaerosols were stained with a DNA marker directly on a filter, followed by fixation, microscopic imaging, and automatic counting. The method was first validated using reference samples prepared by depositing different known concentrations of E. coli onto blank polycarbonate filters. The results indicated a linear response over two orders of magnitude (R2 = 0.9) and an accuracy within ±25%. E. coli were also deposited onto selected ambient PM10 and PM2.5 filter samples to determine if pre-loaded particles would interfere with bioaerosol imaging and counting. It was found that despite an increase in uncertainty (variability), the calibration slope remained within ±10% of unity for both PM2.5 and PM10 samples. Bioaerosol concentrations in ambient samples, as quantified by this method, were on average 14% higher for PM10 than for PM2.5 acquired concurrently in a desert environment of Las Vegas, Nevada. The application of this method to other types of compliance filters, such as Teflon filters and tapes of a Beta Attenuation Monitor (BAM) were also explored in this study. By means of a high-yield approach this method is expected to facilitate bioaerosol research, support exposure and health assessments, and help refine NAAQS for PM2.5 and PM10.

A Rural And Urban Study Of The Food Environment In Select Nevada Geographies, Joseph Nickelson

UNLV Theses, Dissertations, Professional Papers, and Capstones

National and county level examination of urban and rural food environments has taken place, but primary validation of venue existence and in-venue data are lacking. The literature show disparities in access to healthy foods through low density of large grocers/supermarkets, low variety and quality of produce and higher prices for a healthy diet in rural versus urban geographies. Rural areas are of unique concern due to poor health indicators such as higher obesity rates, higher diabetes rates, lower incomes and lower educations than urban residents. The goal of this study was to explore differences in the community and consumer level …

Cli-Fi Cinema: An Epideictic Rhetoric Of Blame, Chloe Louise Powell

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis analyzes the symbolic mechanisms of guilt-redemption as developed by Kenneth Burke within two climate fiction (cli-fi) films: The Day the Earth Stood Still (2008), and Interstellar (2014). In doing so, this thesis offers an account of: (1) each film’s role in providing their audience temporary assuagement of climate change related guilt, and (2) each film’s role in transmitting values and “attitudes” to build and strengthen communities. Because cli-fi films begin from a dystopic vision of a possible future, it fulfills the "blame" function of epideictic discourse to provoke and inspire the "ecological imagination." Through this provocation, the audience …

Targeting Sav Restoration At Lake Mattamuskeet Using Gis And Landsat 8 Data, Lindsey Shanks

Theses, Dissertations and Culminating Projects

Lake Mattamuskeet, a large, shallow lake on the coast of North Carolina, has undergone water quality degradation and submerged aquatic vegetation (SAV) decline over recent years. Water depth and water clarity have been established as key drivers of SAV loss. To target locations for the restoration of SAV in the lake, an analysis that focuses on water clarity, water depth, and current SAV presence was developed. Two separate methodologies were conducted and compared to analyze water clarity in the lake. The first applied four years (2013-2016) of Landsat 8 imagery to a previously developed model that predicts water clarity from …

To What Extent Might Beaver Dam Building Buffer Water Storage Losses Associated With A Declining Snowpack?, Konrad Hafen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Dams built by North American Beaver create natural water storage and slow water as it moves through streams. In portions of streams with beaver dams, these effects have been observed to decrease the peak magnitude of floods and increase base flow during annual summer droughts. In the western United States changes to streamflow patterns have been observed in recent decades with large spring floods coming earlier in the year, causing annual summer droughts to start earlier and last longer. These changes are linked to decreasing snowpack which acts as the most significant natural water storage reservoir by holding onto precipitation …

Decomposition Of Black Mangrove (Avicennia Germinans ) Leaf Litter: Calibrating Estuarine Indicators Of Functional Recovery, Leticia Martinez Contreras

Theses and Dissertations

Decomposition of plant material produced by mangroves and other macrophytes in estuaries occurs in both sediments and the water column. Early and intense processing could be more common in the water. In a previous study, in situ decomposition rates of Black Mangrove (Avicennia germinans ) leaf litter suspended in the water column differed among three estuaries in south Texas with moderate differences in salinity, water temperature, available nitrogen (N), and tidal flow. A series of microcosm experiments were conducted to determine the influence, within observed ranges in the estuaries, of these water variables on mass loss of Black Mangrove …

Investigating The Application Of Multibeam Sonar And Remotely Operated Vehicles In Fish Population Monitoring On Artificial Reefs, Robert Figueroa-Downing

Theses and Dissertations

Implementation of ROVs and multibeam imaging sonar in fisheries research has the potential to improve the accuracy and efficiency of current monitoring practices. This study aimed to 1) compare ROV video and diver abundance estimates; 2) evaluate fish length measurement accuracy from sonar; 3) investigate key differentiating sonar characteristics. Results indicate: 1) Diver surveys captured greater diversity of species; survey methods were comparable with regards to conspicuous species (r = 0.089, p = 0.074); 2) Length measurements from multibeam imaging sonar had high predictive power (Rho = 0.998; p < 0.001) of actual standard lengths and; 3) variations between samples were largely due to swim bladder echo, relative position of the target fish, and schooling characteristics. We conclude that 1) ROVs are less apt at observing cryptic species; 2) The Blueview P900-90 sonar can accurately measure fish length; and 3) swim bladder morphology plays an important role in fish identification.

Range-Wide Prevalence And Impacts Of Pseudocercosporella Inconspicua On Lilium Grayi And An Assessment Of L. Superbum And L. Michauxii As Reservoirs, Cindy L. Barrett

Electronic Theses and Dissertations

Lilium grayi (Gray’s Lily), a southern Appalachian endemic species, is threatened by a Lilium-specific fungal pathogen, Pseudocercosporella inconspicua. The disease is characterized by tan lesions that can cause early senescence, while also lowering seed production and viability. This project tested for P. inconspicua conidia and accessed health at nine locations. The disease was present and ubiquitous across the range of L. grayi. Through identification of P. inconspicua conidia in the field, L. superbum (Turk’s Cap Lily) was identified as an additional host, while L. michauxii (Michaux’s Lily) was disease-free. However, infection was inducible in both species. With …

Black Bears (Ursus Americanus) Versus Brown Bears (U. Arctos): Combining Morphometrics And Niche Modeling To Differentiate Species And Predict Distributions Through Time, Theron Michael Kantelis

Electronic Theses and Dissertations

Late Pleistocene American black bears (Ursus americanus) often overlap in size with Pleistocene brown bears (U. arctos), occasionally making them difficult to diagnose. Large U. americanus have previously been distinguished from U. arctos by the length of the upper second molar (M2). However, the teeth of fossil U. americanus sometimes overlap size with U. arctos. As such, there is need for a more accurate tool to distinguish the two species. Here, 2D geometric morphometrics is applied to the occlusal surface of the M2 to further assess the utility of this tooth for distinguishing U. americanus and …

Phosphomolybdic Acid Catalysis Of Cellulose Hydrolysis, Troy R. Dolmetsch

Undergraduate Honors Theses

Renewable sources such as cellulose derived biofuels are sought after in order to replace fossil fuel sources that are currently used to meet energy demands. Cellulose is a biological polymer composed of a chain of glucose molecules. Hydrolysis of cellulosic materials then has potential to serve as a source of renewable energy in the form of biofuels. The crystalline structure of cellulose is very stable, and current methods of catalyzed hydrolysis are inefficient for industrial application. This project explores the use of phosphomolybdic acid (PMA) in water to catalyze hydrolysis of microcrystalline cellulose. Temperature of hydrolysis was varied from 40 …

Behavioral Paleoecology Of Lower Cambrian Deposit Foragers: Reinterpreting Looping And Meandering Traces Using Optimal Foraging Theory And Quantitative Analysis, Zachary Andrew Jensen

UNLV Theses, Dissertations, Professional Papers, and Capstones

The early Cambrian was a period of transition during which the seafloor environment was changing from a microbial-mat-dominated environment to a bioturbation-dominated environment. The result was a patchy landscape of variable food resources for foraging burrowers to exploit. Looping trace fossils, such Psammichnites gigas and Taphrhelminthopsis nelsoni, appear in strata worldwide during this transitional period, and the ecological niche they filled is a subject of debate among ichnologists. The objectives of this study are (1) to determine the foraging strategies preserved by looping traces through the application of optimal foraging theory and quantitative analysis, and (2) use those results to …

Great Basin Bristlecone Pine Resistance To Mountain Pine Beetle: An Evaluation Of Dendroctonus Ponderosae Host Selection Behavior And Reproductive Success In Pinus Longaeva, Erika L. Eidson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The mountain pine beetle (Dendroctonus ponderosae) is a native bark beetle that attacks and kills most species of pines (Pinus) throughout its range in western North America. Due to the strong relationship between thermal conditions and mountain pine beetle population success, climate change-induced changes in mountain pine beetle outbreaks are a major concern for land managers. Over the past several decades, warmer than average temperatures allowed mountain pine beetle populations to reach epidemic levels across much of the western U.S. and Canada, including high elevations where outbreaks were previously limited by cool temperatures. Many high-elevation pine …

Spatial And Behavioral Patterns Of Captive Coyotes, Jeffrey T. Schultz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Environmental enrichment is a technique used at many captive animal facilities that can improve the well-being of their animals. It seeks to enhance habitat features and promote natural behavior by providing a variety of practical ways for captive animals to control their environmental settings, especially during stressful circumstances. Enclosure features, such as shelter structures, are one tool that promotes wild behavior by adding complexity to an enclosure’s physical environment. Enrichment efforts for captive wildlife are most effective when they are specialized to the biological needs of the animals. Human activity may alter captive animal behavior and utility of enclosure features, …

The Influence Of Aspen Chemistry And The Nutritional Context On Aspen Herbivory, Kristen Y. Heroy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Consumption of aspen by herbivores is one major force causing aspen decline in North America. In this Dissertation, I aimed to determine why herbivores prefer browsing on certain aspen stands over others, and why they prefer consuming aspen that contains chemical defenses over understory forages like grasses, forbs, and shrubs. I explored the influence of nutrients and chemical defenses within aspen on aspen intake and preference by lambs in pen experiments. I also explored drivers of aspen preference on the landscape by looking at relationships between aspen herbivory, indicators of aspen health, amount of nutrients available in the understory, and …

Sclerocactus Wetlandicus: Habitat Characterization, Seed Germination And Mycorrhizal Analysis, Kourtney T. Harding

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Uinta Basin hookless cactus (Sclerocactus wetlandicus) is a threatened species native to Eastern Utah. The cactus is found in a landscape highly disturbed by non-renewable energy production. To understand the environmental conditions that support natural growth of this cactus, we asked what types of plants were present in the same areas as the cactus, and if the types of plants were different in environments that were disturbed. From our assessment, we determined that the types of plants present in disturbed areas were drastically different from those present in undisturbed locations. Areas previously used for energy production are …

Effect Of Foliage And Root Carbon Quantity, Quality, And Fluxes On Soil Organic Carbon Stabilization In Montane Aspen And Conifer Stands In Utah, Antra Boča

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Soil organic carbon (SOC) positively affects many soil properties (e.g., fertility and water holding capacity), and the amount of carbon (C) in soil exceeds the amount in the atmosphere by about three times. Forest soils store as much C as is found in trees. Tree species differ in their effect on SOC pools. Quaking aspen forests in the Western US often store more stable SOC in the mineral soil than nearby conifers. During the last decades a decline in aspen cover, often followed by conifer encroachment, has been documented. A shift from aspen to conifer overstories may negatively affect the …