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An Evaluation Of Stocking And Habitat Influences On Channel Catfish In Lentic Ecosystems Of The Great Plains, Lindsey K. Chizinski May 2012

An Evaluation Of Stocking And Habitat Influences On Channel Catfish In Lentic Ecosystems Of The Great Plains, Lindsey K. Chizinski

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

Channel catfish Ictalurus punctatus is an important sport fish, particularly in the Great Plains. In Nebraska, a majority of anglers target channel catfish, and fishing activities are a vital part of the state’s economy. Lentic water bodies provide the primary fishing opportunity for catfish anglers in Nebraska. Despite the popularity and economic importance of channel catfish, little is known of its population dynamics or habitat requirements, and existing studies often profile river populations. Current standards for sampling channel catfish in lentic systems often yield inadequate catch to assess populations. The objective of this study was to utilize a recently developed …


Understanding Of The Hydrologic Connections Between Wide-Channel And Adjacent Aquifers Using Numerical And Field Techniques, Cheng Cheng May 2012

Understanding Of The Hydrologic Connections Between Wide-Channel And Adjacent Aquifers Using Numerical And Field Techniques, Cheng Cheng

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

Streambed sedimentary structure plays a vital role in controlling the interactions between surface water and groundwater. In the study, three rivers -the Big Blue River, the Little Blue River, and the lower reach of the Platte River in Nebraska were chosen to characterize the shallow streambed for the two types of rivers (braided and meandering rivers) and investigated the variations of the streambed electrical and hydraulic conductivities with depth. In-situ and laboratory permeameter tests were conducted to determine streambed hydraulic conductivity up to 20 m below the channel surface in the three rivers. Additionally, the electrical conductivity logs were obtained …


Sediment Removal From The San Gabriel Mountains, Mary C. Ferguson May 2012

Sediment Removal From The San Gabriel Mountains, Mary C. Ferguson

Pitzer Senior Theses

The issue of sediment removal from the San Gabriel Mountains has been a complex issue that has created problems with beach replenishment, habitat destruction and the need to spend millions of dollars at regular intervals to avoid safety hazards. Most recently 11 acres of riparian habitat, including 179 oaks and 70 sycamores, were removed for sediment placement. Other sites including Hahamongna Watershed Park and La Tuna Canyon also face a similar fate. This thesis questions: How did we get to this point of destroying habitat to dump sediment which is viewed as waste product? What are the barriers for creating …


Gray Wolf Rising: Why The Clash Over Wolf Management In The Northern Rockies Calls For Congressional Action To Define "Recovery" Under The Endangered Species Act, W. Ryan Stephens May 2012

Gray Wolf Rising: Why The Clash Over Wolf Management In The Northern Rockies Calls For Congressional Action To Define "Recovery" Under The Endangered Species Act, W. Ryan Stephens

William & Mary Environmental Law and Policy Review

No abstract provided.


Exploring The Seed Bank Dynamics Of Red Brome: Longevity, Density, And Relationship To Fire, Benjamin S. Jurand May 2012

Exploring The Seed Bank Dynamics Of Red Brome: Longevity, Density, And Relationship To Fire, Benjamin S. Jurand

UNLV Theses, Dissertations, Professional Papers, and Capstones

This research explores several untested aspects of the seed bank characteristics of red brome (Bromus rubens), an invasive annual grass in southwestern United States arid lands. Red brome is a formidable competitor to native plant species, both annual and perennial alike, and produces many seeds that germinate easily. The stalks of red brome contribute continuous-cover fuel loads that facilitate wildfires destructive to mature native Mojave Desert plant communities. This makes it a priority species for land managers, particularly when dealing with recovery after fire.

This project addressed questions related to the longevity of red brome seeds in soil seed banks …


The Effect Of Phosphite On Mycorrhiza Formation In American Chestnut (Castanea Dentata), Matthew T. Perkins May 2012

The Effect Of Phosphite On Mycorrhiza Formation In American Chestnut (Castanea Dentata), Matthew T. Perkins

Honors Theses

One of the primary hindrances to Castanea dentata restoration in the Southeast is the root rot disease caused by the fungus-like microorganism Phytophthora cinnamomi. Root rot can be combated by the application of mono- and di-potassium salts of phosphorous acid, which are marketed as phosphite fungicides. Despite its value in preventing infection by P. cinnamomi it is also thought that phosphite may impede root colonization by beneficial, ectomycorrhizal fungi. I hypothesized that plants given a routine application of phosphite will display fewer mycorrhizas in the root tips than those plants that were not treated with potassium phosphite. Therefore I attempted …


Arsenic Contamination In Groundwater In Vietnam: An Overview And Analysis Of The Historical, Cultural, Economic, And Political Parameters In The Success Of Various Mitigation Options, Thuy M. Ly May 2012

Arsenic Contamination In Groundwater In Vietnam: An Overview And Analysis Of The Historical, Cultural, Economic, And Political Parameters In The Success Of Various Mitigation Options, Thuy M. Ly

Pomona Senior Theses

Although arsenic is naturally present in the environment, 99% of human exposure to arsenic is through ingestion. Throughout history, arsenic is known as “the king of poisons”; it is mutagenic, carcinogenic, and teratogenic. Even in smaller concentrations, it accumulates in the body and takes decades before any physical symptoms of arsenic poisoning shows. According to the World Health Organization (WHO), the safe concentration of arsenic in drinking water is 10 µg/L. However, this limit is often times ignored until it is decades too late and people begin showing symptoms of having been poisoned.

This is the current situation for Vietnam, …


Neustonic Plastic In The Los Angeles River, Annie M. Tran May 2012

Neustonic Plastic In The Los Angeles River, Annie M. Tran

Pomona Senior Theses

The characterization of neustonic plastic found in the Los Angeles River was completed in this study. 3 water samples were collected from the river on April 30, 2011 in Long Beach, CA using a 0.5 mm manta trawl. The plastic was separated from organic material, divided into 3 class sizes (0.5 mm, 1.4 mm, and 2.44 mm), and identified and sized under a microscope. Plastic was found in all three samples and categorized into seven categories. Paper, plastic, and styrofoam were present in all three samples. Styrofoam contributed the greatest percentage of the plastic found among the samples. Plastic film …


Integrating Remote Sensing And Ecosystem Models For Terrestrial Vegetation Analysis: Phenology, Biomass, And Stand Age, Gong Zhang May 2012

Integrating Remote Sensing And Ecosystem Models For Terrestrial Vegetation Analysis: Phenology, Biomass, And Stand Age, Gong Zhang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Terrestrial vegetation plays an important role in global carbon cycling and climate change by assimilating carbon into biomass during the growing season and releasing it due to natural or anthropogenic disturbances. Remote sensing and ecosystem models can help us extend our studies of vegetation phenology, aboveground biomass, and disturbances from field sites to regional or global scales. Nonetheless, remote sensing-derived variables may differ in fundamental and important ways from ground measurements. With the growth of remote sensing as a key tool in geoscience research, comparisons to ground data and intercomparisons among satellite products are needed. Here I conduct three separate …


Investigating Three Decades Of Vegetation Change In A Mojave Desert Mountain Range, Chris Lee Roberts May 2012

Investigating Three Decades Of Vegetation Change In A Mojave Desert Mountain Range, Chris Lee Roberts

UNLV Theses, Dissertations, Professional Papers, and Capstones

This project is a vegetation change study spanning 29 years in the Newberry Mountains of Southern Nevada. Long term monitoring data are crucial for understanding the effects of climate change on vegetation dynamics. Successful management intervention in vegetation change will require identification of early indicator plant species and their responses to climatic cues. This project is one of the oldest comparisons of resurveyed Mojave vegetation community plots with repeatable methodology and the longest survey interval reported for the southeastern Mojave Desert. 103 plots were relocated and resurveyed based on data methods in Jim Holland's thesis titled "A Vegetative Analysis of …


Water Infrastructure Challenges In Urbanizing Environments: A Case Study Of The 2009 Logan Canal Landslide, Kathryn Davis Henderson May 2012

Water Infrastructure Challenges In Urbanizing Environments: A Case Study Of The 2009 Logan Canal Landslide, Kathryn Davis Henderson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In July, 2009 in Logan, Utah, a wet, steep hillside failed, leveling a home below and destroying an irrigation canal that ran along the hill. Three people were killed. The event and the resulting policy changes present an opportunity to uncover how frames, or social constructions, play into the policy development cycle. This case also uncovers the nuances involved when old infrastructure takes on new social meanings. Planners and policymakers that pay attention to frames and social dimensions may be able to minimize conflict.

The landslide received immediate media attention and spurred state legislation on canal safety. The event had …


The Influence Of Geology And Other Environmental Factors On Stream Water Chemistry And Benthic Invertebrate Assemblages, John R. Olson May 2012

The Influence Of Geology And Other Environmental Factors On Stream Water Chemistry And Benthic Invertebrate Assemblages, John R. Olson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Determining if a stream has been degraded by human activities requires knowing what that stream’s natural water quality and freshwater species composition would likely be without any alteration. However stream natural conditions vary greatly from stream to stream, making predicting natural conditions difficult. To determine natural stream conditions, I developed models to predict natural stream water chemistry at individual streams across the western USA. Specifically, the models predict a stream’s electrical conductivity (a measure of the amount of solids dissolved in water), acid neutralization capacity, and concentrations of calcium, magnesium, sulfate, total phosphorus, and total nitrogen. These models predict chemistry …


The Survival And Growth Of Adult Bonneville Cutthroat Trout (Oncorhynchus Clarkii Utah) In Response To Different Movement Patterns In A Tributary Of The Logan River, Utah, Jared W. Randall May 2012

The Survival And Growth Of Adult Bonneville Cutthroat Trout (Oncorhynchus Clarkii Utah) In Response To Different Movement Patterns In A Tributary Of The Logan River, Utah, Jared W. Randall

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In the past many inland trout species were believed to be sedentary, only occupying small stream segments (20 meters) during their life span. Recently it has been found that cutthroat trout do move and many populations do contain both mobile and non-mobile strategies. Most organisms move to attain greater growth rates, but movement also leads to higher detection by predators. Both mobile and non-mobile strategies have been observed in Spawn creek, a tributary of the Logan River in Northern Utah. My research evaluated the movement patterns, survival, and growth of adult Bonneville cutthroat trout Oncorhynchus clarkii Utah. My objectives …


Carbon Sequestration On Utah Rangelands: A Landowner Perspective, Seth Cook May 2012

Carbon Sequestration On Utah Rangelands: A Landowner Perspective, Seth Cook

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Carbon sequestration is the removal of carbon dioxide from the air and storing it in plants and soil through natural processes. Rangelands can be managed to sequester carbon and mitigate climate change. Supported by the Utah Agricultural Experiment Station, this study assessed Utah rangeland owners’ perceptions of carbon sequestration and explored factors influencing their likelihood of participation in relevant programs. Data were collected through interviews and a statewide survey of Utah rangeland owners. Over two-thirds of respondents were aware of carbon sequestration and viewed it positively. Those who thought the climate had been changing over the past 30 years tended …


Instances Of Conflict And Cooperation: An Exploration Into The Role Of Competition Between Usda-Wildlife Services And Wildlife Control Operators, Gary J. Bezzant Jr. May 2012

Instances Of Conflict And Cooperation: An Exploration Into The Role Of Competition Between Usda-Wildlife Services And Wildlife Control Operators, Gary J. Bezzant Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In early 1994 the United States Department of Agriculture’s Animal Damage Control agency implemented a directive providing guidance to help avoid competition between themselves and private businesses, known as Wildlife Control Operators (WCOs) engaging in similar work. Nearly two decades later some WCOs still complain about having to compete with the Animal Damage Control agency, now named Wildlife Services. Other businesses report enjoying a cooperative relationship with the agency.

I analyzed four policies that regulate competition between Wildlife Services and WCOs and found that there is a good amount of guidance given to Wildlife Services in regards to their competitive …


Analysis Of A Stormwater Pond For Stormwater Management On The Buffalo State College Campus – Year 1 Operation Conditions, Jessica Bakert May 2012

Analysis Of A Stormwater Pond For Stormwater Management On The Buffalo State College Campus – Year 1 Operation Conditions, Jessica Bakert

Multidisciplinary Studies Theses

Under U.S.EPA Phase II stormwater regulations Buffalo State was required to develop a stormwater management plan. This plan pursues both hard‐engineering and low impact development approaches for stormwater management. As part of the plan, a detention pond came on‐line in early summer, 2010, to collect flow before it discharges to Scajaquada Creek. The objective of this study was to assess the detention pond impact on water quantity and quality prior to discharge to the creek. A meter was installed in 2007 (pre‐construction) and 2010 (post‐construction) to record stormwater discharge to Scajaquada Creek. Regression analysis between rainfall and runoff characteristics showed …


Mathematical Modeling Of Fluid Spills In Hydraulically Fractured Well Sites, Oluwafemi Michael Taiwo May 2012

Mathematical Modeling Of Fluid Spills In Hydraulically Fractured Well Sites, Oluwafemi Michael Taiwo

Graduate Theses and Dissertations

Improved drilling technology and favorable energy prices have contributed to the rapid pace at which the exploitation of unconventional natural gas is taking place across the United States. As a natural gas well is being drilled, reserve pits are constructed to hold the drilling fluids and other materials returned from the drilling process. These reserve pits can fail, and when they do, plant and animal life of the surrounding area may be adversely affected. This project develops a screening tool for a suitable location for a reserve pit. This work will be a critical piece of the Infrastructure Placement Analysis …


Natural And Constructed Wetlands For Ecosystem And Engineering Services In The Arid And Semi-Arid Regions, Achyut Raj Adhikari May 2012

Natural And Constructed Wetlands For Ecosystem And Engineering Services In The Arid And Semi-Arid Regions, Achyut Raj Adhikari

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Las Vegas Wash (LVW) has undergone significant wetlands degradation and soil erosion over the past thirty years due to increasing flow resulting from urbanization and large rainfall events in the Las Vegas Valley Watershed. The increased flow and associated pollution load in the LVW and its adverse impact in Lake Mead have alerted stakeholders to pay a greater attention to explore alternative measures for rehabilitation of wetland ecosystems. This dissertation, using the case of changes in LVW, analyzes and describes ecological and engineering services provided by wetlands in arid and semi-arid regions and provides a knowledge base that can …


The New American Conservation Movement: New Strategies, Focus And Organizations For The 21st Century, Amy Deanna Northrup May 2012

The New American Conservation Movement: New Strategies, Focus And Organizations For The 21st Century, Amy Deanna Northrup

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation provides evidence of the emergence of a new conservation movement in the United States. The strategic, tactical and organizational approaches of traditional conservation efforts, which began in the early 1900s, have shifted during the last two decades. Specifically, the new conservation movement is characterized by three distinct changes. First, many of the well-established conservation organizations, such as the Sierra Club and National Audubon Society, have largely abandoned their traditional focus on increasing the number of acres preserved; instead more defensive and fragmented forms of conservation now reign. The second change to the conservation movement involves a dramatic expansion …


Spawning, Veliger Growth And Desiccation Of Dreissena Bugensis, Lynn Schwaebe May 2012

Spawning, Veliger Growth And Desiccation Of Dreissena Bugensis, Lynn Schwaebe

UNLV Theses, Dissertations, Professional Papers, and Capstones

Quagga (Dreissena bugensis) mussel veliger growth was compared under two dietary conditions: 1) only seston present in Lake Mead water; and 2) Lake Mead seston plus algae (Isochrysis galbana). Shell length, width, and area were compared as a function of time for the two treatments. It was expected that mussels would exhibit faster growth when supplemented with I. galbana than with Lake Mead water alone. However, no significant difference was observed between the control and I. galbana treatments. This result was unexpected and may have been caused by water quality, the nutritional content of Lake Mead seston, and/or over feeding. …


Understanding Urban Sustainability And Quality Of Life: A System Dynamics Approach, Abby Elizabeth Beck May 2012

Understanding Urban Sustainability And Quality Of Life: A System Dynamics Approach, Abby Elizabeth Beck

UNLV Theses, Dissertations, Professional Papers, and Capstones

For an urban area to be sustainable, its resources cannot be depleted faster than they can replenish. If an urban area is to provide a high quality of life (QOL), it must offer and maintain an amenity package that satisfies its resident's preferences. Past studies on these topics all have a common thread: sustainability and QOL both pertain to people's relationship to capital. Capital is something that can accumulate and add value to a person or society. If sustainability and QOL are a function of people's relationship with capital, how they use it, deplete it, replenish it and transform it …


A Pre-Paving Baseline Inventory Of Vehicle-Related Mortality On Mule Deer Along, Seep Ridge Road, Book Cliffs, Utah, D. Alex Hansen May 2012

A Pre-Paving Baseline Inventory Of Vehicle-Related Mortality On Mule Deer Along, Seep Ridge Road, Book Cliffs, Utah, D. Alex Hansen

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Part I:

The Seep Ridge road is the major route used to access the Book Cliffs from Uintah County. For many years the County has expressed interest in paving the road in order to improve access to this remote portion of the County. In 2011 Uintah County received Bureau of Land Management (BLM) approval for the project and began construction on the road. There have been many concerns expressed concerning the Seep Ridge Road paving project, including impacts to mule deer. The Utah Division of Wildlife, sportsmen and conservation groups are concerned that upgrading the road may lead to a …


Small-Wind And Residential Photovoltaic In Nebraska: Barriers To Development, Jerrod Bley May 2012

Small-Wind And Residential Photovoltaic In Nebraska: Barriers To Development, Jerrod Bley

Department of Environmental Studies: Undergraduate Student Theses

No abstract provided.


Achieving Sustainability In The Craft Brewing Industry, Mike Boden May 2012

Achieving Sustainability In The Craft Brewing Industry, Mike Boden

Department of Environmental Studies: Undergraduate Student Theses

Continued growth in the craft brewing industry, coupled with natural resource limitations suggests the need for implementation of sustainable initiatives on a wide scale. These initiatives discussed include the areas of economic sustainability through cooperative growth and equilibrium, social sustainability through employee and community development, and environmental sustainability through energy and water conservation and renewable energy use. Specific techniques to achieve sustainability in the craft brewing industry are reviewed alongside case studies of craft breweries currently implementing these techniques. A sustainable metric is outlined for use in accomplishing these goals.


Predicting Lemna Minor Growth Rate Response To Temperature Fluctuations, Elizabeth Novich May 2012

Predicting Lemna Minor Growth Rate Response To Temperature Fluctuations, Elizabeth Novich

Department of Environmental Studies: Undergraduate Student Theses

The effects of global climate change on populations may be further understood when environmental variability is included. There are strong theoretical reasons that support the idea that environmental fluctuations matter when studying ecological systems. In order to further explore this, we parameterized a model of the growth rate of Lemna minor at constant temperatures and made predictions on how L. minor would respond to fluctuating temperatures based on this model. There were four trials performed that compared the difference between growth rates at constant and fluctuating temperatures in order to test if our predictions were correct. For our results, only …


Microcystin Toxin In Nebraska Lakes With Correlation Of Population And Agriculture Use, Kaitlyn Haras May 2012

Microcystin Toxin In Nebraska Lakes With Correlation Of Population And Agriculture Use, Kaitlyn Haras

Department of Environmental Studies: Undergraduate Student Theses

No abstract provided.


Do Tree Species In A Bornean Mixed Dipterocarp Forest Display Preferential Uptake Of Different Nitrogen Forms?, Jocelyn Onley May 2012

Do Tree Species In A Bornean Mixed Dipterocarp Forest Display Preferential Uptake Of Different Nitrogen Forms?, Jocelyn Onley

Department of Environmental Studies: Undergraduate Student Theses

Lambir Hills National Park in Malaysian Borneo is composed of dipterocarp tree species which specialize on different soil types. Although the mechanisms contributing to this distribution of tree species are unknown, one hypothesis is that tree species at Lambir differ in their preferences for different nitrogen forms. In this study we investigated (1) whether clay soil and sandy loam soil types at Lambir differ in the availability of ammonium and nitrate and (2) whether tree species specializing on either clay soil or sandy loam soil at Lambir have differing preferences or capacities to take up ammonium, nitrate, or glycine (organic …


Territories,Territoriality, And Conservation Of The Louisiana Waterthrush And Its Habitat, The Watershed Of The Upper Buffalo National River, Leesia Cheryl Marshall May 2012

Territories,Territoriality, And Conservation Of The Louisiana Waterthrush And Its Habitat, The Watershed Of The Upper Buffalo National River, Leesia Cheryl Marshall

Graduate Theses and Dissertations

The Louisiana Waterthrush, Parkesia motacilla, is a migratory wood-warbler and breeding season resident of the eastern United States. Males defend breeding territories that extend linearly along clear, fast-flowing, gravel-bottomed, forest streams. Defense includes two song types, primary and extended song. As riverine specialists, birds rely upon aquatic invertebrates as prey and riparian habitat features for nesting. They use a unique foraging maneuver, leaf-pulling, that involves picking up or pulling a leaf from water, and turning it over to search for prey. Their relationship with riparian habitat introduces potential for Louisiana Waterthrushes to serve as indicators of stream health. The …


Biological Strategies And Mathematical Approaches For Limiting Bacterial Contaminants And Chemical Pollutants In Bioethanol Fermentations, Alia Chahed Ep Limayem May 2012

Biological Strategies And Mathematical Approaches For Limiting Bacterial Contaminants And Chemical Pollutants In Bioethanol Fermentations, Alia Chahed Ep Limayem

Graduate Theses and Dissertations

During the most recent decades increased interest in fuel from biomass in the United States and worldwide has emerged each time petroleum derived-gasoline registered well publicized spikes in price. The willingness of the U.S. government to face the issues of more heavily high-priced foreign oil and climate change has led to more investment on plant-derived sustainable biofuel sources. Biomass derived from corn has become one of the primary feedstocks for bioethanol production for the past several years in the U.S. However, the argument of whether to use food as biofuel has led to a search for alternative non-food sources. Consequently, …


Fate Of Cerium Oxide (Ceo₂), Nanoparticles In Landfill Leachate, Casey Marie Ezyske May 2012

Fate Of Cerium Oxide (Ceo₂), Nanoparticles In Landfill Leachate, Casey Marie Ezyske

Theses, Dissertations and Culminating Projects

Nanomaterial (NM) based manufacturing is predicted to grow to 15% of the global manufacturing economy by 2014. Subsequent to their use, most of the engineered nanomaterials (ENMs), man-made particles with at least dimension between 1 and 100 nm, will be disposed of in landfills. Landfill leachate is highly contaminated wastewater containing a variety of constituents that may affect the fate and transport of the nanomaterials. In this study, the size and zeta potential of cerium oxide (CeO2), an industrially important nanomaterial, was investigated in different solution matrices (Milli-Q water, a real landfill leachate, KC1 solution, and humic acid …