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Full-Text Articles in Physical Sciences and Mathematics

Effects Of Ecological Restoration Techniques In Glen Canyon National Recreation Area, Simone Ka-Voka Jackson May 2019

Effects Of Ecological Restoration Techniques In Glen Canyon National Recreation Area, Simone Ka-Voka Jackson

UNLV Theses, Dissertations, Professional Papers, and Capstones

A better understanding of key ecological restoration techniques can inform land management in the Southwest on restoration options for areas infested by invasive grasses that can pose threats to ecosystems, from changes in nutrient cycling to altered fire regimes. In the semi-arid desert of Glen Canyon National Recreation Area (GLCA), several exotic grasses pose risks to local ecosystems: Saccharum ravennae, a relatively new invasive perennial grass, and Bromus rubens and Bromus tectorum, widespread annual grasses. In this study, multiple ecological restoration techniques were implemented to assess their effects on native and nonnative vegetation on sites invaded by the non-native grasses …


Living On The Edge: Assessing The Effects Of Catastrophic Fire On Plants Utilized By Two Endemic Subspecies Of Spring Mountains Butterflies, Charles Ryan Herrmann May 2017

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 …


Water Source Partitioning For Shrubland Transpiration In A Mixed Phreatophytic Plant Community, Amanda Jean Wagner Aug 2016

Water Source Partitioning For Shrubland Transpiration In A Mixed Phreatophytic Plant Community, Amanda Jean Wagner

UNLV Theses, Dissertations, Professional Papers, and Capstones

Groundwater in the basins of east central Nevada (Great Basin Desert, NV) has been permitted for export to southern Nevada. These basins are also vulnerable to changes in climate that could lead to declining recharge. Any decline in groundwater levels no matter the driving force could significantly impact phreatophytes (deep rooted shrubs), which utilize water from both the vadose zone and the capillary fringe to meet plant water needs, to support growth, and for overall health. A reduction in groundwater due to these forces could have a significant impact on the decoupling of phreatophytes from what is normally a reliable …


Predicted Performance Of A Skytherm North, A Highly Insulated Building Envelope System And A Frost Protected Shallow Foundation, Kitrina Ann Stratton Dec 2014

Predicted Performance Of A Skytherm North, A Highly Insulated Building Envelope System And A Frost Protected Shallow Foundation, Kitrina Ann Stratton

UNLV Theses, Dissertations, Professional Papers, and Capstones

How do you design a durable, sustainable, and financeable Net Zero Energy house for a cold weather climate using little or no external energy that is also affordable? Reviewing all of the factors that would influence the design and materials selection of an appropriate response to the issues, the perfect system for housing people, whether it is in response to affordability, durability, comfort, cultural sensitivity, appearance or being locally appropriate, is using some kind of straw bale construction system with an integrated frost protected shallow foundation and a SkyTherm North design.

The focus and intention of this research is to …


Building Envelope For Energy-Efficient Residential Homes, A Case Study For The U.S. Department Of Energy Challenge Home Student Design Competition, Milica Tajsic Aug 2014

Building Envelope For Energy-Efficient Residential Homes, A Case Study For The U.S. Department Of Energy Challenge Home Student Design Competition, Milica Tajsic

UNLV Theses, Dissertations, Professional Papers, and Capstones

With the continuous rise of population and expansion of urban areas, the need for additional housing and infrastructure is growing rapidly. Building sector is consuming a vast majority of the natural resources to meet the needs of urbanization and is in need of efficient, sustainable solutions that are viable for the customer, the economy and the environment. The building sector is both the problem and the solution to the issues of the carbon footprint of our society (Architecture 2030, 2011).

The envelope (roofs, walls, and foundations) and windows typically account for 36% of overall energy use, or about 14.3 quads …


Pronghorn (Antilocapra Americana) Offspring Recruitment On The Carrizo Plain National Monument: Evaluating The Effects Of Low Population Density And Marginal Habitat Quality., Diego Ramirez Johnson May 2014

Pronghorn (Antilocapra Americana) Offspring Recruitment On The Carrizo Plain National Monument: Evaluating The Effects Of Low Population Density And Marginal Habitat Quality., Diego Ramirez Johnson

UNLV Theses, Dissertations, Professional Papers, and Capstones

Demographic fluctuation among ungulate populations is strongly linked to variability in recruitment. Rates of recruitment are subject to various forms of density-dependent and density-independent regulation. For species which benefit from the presence of conspecifics, reduced population density can decrease rates of recruitment and trigger a decline in per capita growth. Termed the Allee effect, this scenario can cause demographic collapse and population extinction. For many ungulate species, predation on juveniles is reduced when the timing and distribution of births is synchronized within a local population. Because birth synchrony is density-dependent, it may act as a mechanism for the Allee effect …


Restoration Of Biological Soil Crust On Disturbed Gypsiferous Soils In Lake Mead National Recreation Area, Eastern Mojave Desert, Lindsay P. Chiquoine Dec 2012

Restoration Of Biological Soil Crust On Disturbed Gypsiferous Soils In Lake Mead National Recreation Area, Eastern Mojave Desert, Lindsay P. Chiquoine

UNLV Theses, Dissertations, Professional Papers, and Capstones

Biological soil crusts (BSCs) are sensitive to anthropogenic disturbances. Natural recovery takes many years. Active restoration decreases recovery time. Native BSC inocula, which included lichens and mosses, salvaged from gypsiferous soil habitats in Lake Mead National Recreation Area (LMNRA) in the eastern Mojave Desert were stored dry for two years and applied to disturbed soil after a road reconstruction in LMNRA and also used in laboratory experiments to test inoculation technique effectiveness. After 18 months, field results revealed positive relationships between inoculation and the presence of macroscopic BSC cover, cyanobacteria abundance, soil stability, and ammonium concentrations. Chlorophyll fluorescence monitoring of …


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 …


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 …


Fenestration Studies On Building Energy Using The Facade Evaluation Facility, Wendell Cocina Dec 2011

Fenestration Studies On Building Energy Using The Facade Evaluation Facility, Wendell Cocina

UNLV Theses, Dissertations, Professional Papers, and Capstones

The project was developed to assess several types of facades and their influence on building energy, mainly focused on windows and other building fenestrations. Requirements for the facility are stated in this paper alongside corresponding solutions. The facility is designed to represent a section of a building façade. Experimenting on a wide range of fenestrations including windows with integrated PV elements was the primary prerequisite. The option of removable façade configurations was used and allowed testing specimens to be changed effortlessly. Instrumentation and data acquisition are discussed including calibration and uncertainty analysis. Investigation of the air conditioning unit was concluded …


Telework Within The Bureau Of Reclamation Lower Colorado Region Office, Theresa Lee, Lynne Arnold, John Wagner, Elias Samorano, Anita Morgan May 2011

Telework Within The Bureau Of Reclamation Lower Colorado Region Office, Theresa Lee, Lynne Arnold, John Wagner, Elias Samorano, Anita Morgan

UNLV Theses, Dissertations, Professional Papers, and Capstones

A team of researchers from The University of Nevada, Las Vegas were invited by management to observe, assess, and offer recommendations. It was determined by the research team that the first step to improving participation would be to observe the functional telework policy, compare and contrast it with the Department of the Interior standards, and offer recommendations to generate data necessary to develop an updated telework policy by management. The recommendations made by this group include creating an employee eligibility list, tracking actual participation by creating a renewal policy for employees choosing to telework. It is also recommended that a …


Fire On The Mountain: Growth And Conflict In Colorado Ski Country, Michael W. Childers May 2010

Fire On The Mountain: Growth And Conflict In Colorado Ski Country, Michael W. Childers

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation examines the environmental, economic, and cultural conflicts over the private development of ski resorts in Colorado's National Forests between 1910 and 2000. Downhill skiing emerged as an increasingly popular winter activity during the first half of the twentieth century, particularly in western state such as Colorado. A part of the a larger outdoor recreational boom throughout the United States' during the interwar years, downhill skiing challenged the Forest Service's ability to meeting the public's growing appetite for year-round recreational opportunities. These challenges increased following World War II as the nation's growing population and affluence drew millions to their …


An Exploratory Study On Energy Consumption Of Energy Star And Non-Energy Star Homes, Prajakta Kulkarni May 2010

An Exploratory Study On Energy Consumption Of Energy Star And Non-Energy Star Homes, Prajakta Kulkarni

UNLV Theses, Dissertations, Professional Papers, and Capstones

The reduction of energy consumption is one of the economic necessities in the United States due to depleting energy sources in the world. The construction industry is stepping forward to reduce the energy consumption of buildings by efficient designs or by constructing buildings with energy efficient materials and features. In 1992, the U.S. Environmental Protection Agency (EPA) and Department of Energy (DOE) introduced the Energy Star Program to promote energy efficient products with the same or improved services. According to the EPA, Energy Star homes, which use these products, will consume 20 to 30 percent less energy than non-Energy Star …


Transforming Space Into Place: Development, Rock Climbing, And Interpretation In Red Rock Canyon National Conservation Area, 1960-2010, Megan Sharp Weatherly May 2010

Transforming Space Into Place: Development, Rock Climbing, And Interpretation In Red Rock Canyon National Conservation Area, 1960-2010, Megan Sharp Weatherly

UNLV Theses, Dissertations, Professional Papers, and Capstones

Though Americans tend to view wilderness as separate from nature, environmental historians have argued that wilderness is a cultural construct more than a quantifiable geographic category. Red Rock Canyon National Conservation Area (NCA), a 195,000-acre tract located west of Las Vegas, Nevada, is one such cultural construction. Since 1960, this BLM-managed parcel has served as a local and regional expression of broader, national trends in outdoor recreation, interpretation, and development and thereby forced visitors to engage (often unknowingly) in a cultural dialogue about consumerism, technology, and identity. With information from newspapers, archival collections, oral histories, and government documents, this thesis …


Parametric Study Of Efficiency Measures For Home Energy Conservation In Las Vegas, Nevada, Todd M. France Jan 2009

Parametric Study Of Efficiency Measures For Home Energy Conservation In Las Vegas, Nevada, Todd M. France

UNLV Theses, Dissertations, Professional Papers, and Capstones

Pulte Homes, a production home builder and community developer partnering with the U.S. Department of Energy's Building America program, has collaborated with the Center for Energy Research at the University of Nevada, Las Vegas and NV Energy, the local electric utility, on an energy conservation project in the Las Vegas Valley.

This study entails four model homes at a new development in the Summerlin community of Las Vegas, Nevada, named Villa Trieste. The home models, ranging in floor plan area from 1,487 to 1,777 square feet, have been constructed under the Environments for Living program and are LEED (Leadership in …


Empirically Derived Formulas To Predict Indoor Maximum, Average, And Minimum Temperatures In Roofpond Buildings Using Minimum Climatic Information, Ibrahim Kivarkis Kako Jan 2009

Empirically Derived Formulas To Predict Indoor Maximum, Average, And Minimum Temperatures In Roofpond Buildings Using Minimum Climatic Information, Ibrahim Kivarkis Kako

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis introduces an empirically developed formula to predict the comfort conditions and thermal performance of a Skytherm(TM) Southwest Roofpond placed over a light-weight un-insulated structure built at the School of Architecture at the University of Nevada, Las Vegas.

The predictive formula introduced in this study may be used in different parts of the world (particularly developing nations where insulation and air-conditioning are rarely used) to predict the performance of a Skytherm(TM) Southwest Roofpond using minimal climate data.

The data collected in the experimental setup at the Natural Energies Advanced Technologies Laboratory included outside and inside temperatures of various surfaces …


Examining The Influence Of Restaurant Green Practices On Customer Return Intention, Audrey L. Szuchnicki Jan 2009

Examining The Influence Of Restaurant Green Practices On Customer Return Intention, Audrey L. Szuchnicki

UNLV Theses, Dissertations, Professional Papers, and Capstones

In recent years there has been an increased awareness of how the actions of the foodservice industry are effecting the environment. With this awareness we have begun to see a change in priorities for both new and existing businesses. At the forefront of this change in the "green" direction is the GRA who certifies how eco-friendly an establishment is based on its' environmental guidelines. This study will examine the correlation between customer return intention and the institution of green practices within a restaurant setting. The expected outcome would be that a restaurant that is certified green or, implementing measures to …


Increasing The Recycling Rate In Clark County, Nevada, Emerald Laija Dec 2008

Increasing The Recycling Rate In Clark County, Nevada, Emerald Laija

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to identify and evaluate policies that could increase the amount of municipal solid waste recycled in Clark County, Nevada. Clark County has not met the Nevada State goal of a 25% recycling rate since it was established by the Nevada Legislature in 1991. Using the system dynamics problem solving approach, a model for Clark County was adapted from a model developed by Stave (2008) to test policy options. There was no feedback in the model due to the long lifespan of the landfill servicing Clark County and the relatively shorter time horizon of the …


Understanding The Motivations Of Rock Climbers: A Social Worlds Study, Amy Miller Ansari Jan 2008

Understanding The Motivations Of Rock Climbers: A Social Worlds Study, Amy Miller Ansari

UNLV Theses, Dissertations, Professional Papers, and Capstones

Rock climbing affects public lands through erosion, destruction of vegetation, and disturbance to historical sites. Minimum impact messages can help reduce impacts but requires understanding characteristics of the message recipient. The purpose of this study was to understand the motivations of rock climbers to help land managers design more effective minimum impact messages. This study assesses the motivations of rock climbers using a social worlds approach, focusing on the sub-worlds of. traditional climbers, sport climbers, and boulderers. I found that traditional climbers are most motivated to pursue a wilderness experience, climb in a natural wilderness setting, and climb in quiet …


The Contribution Of Environmental Variables On Small Mammal Species Richness And Relative Abundance In Eastern Nevada, Stephanie Harris May 2006

The Contribution Of Environmental Variables On Small Mammal Species Richness And Relative Abundance In Eastern Nevada, Stephanie Harris

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study is to determine how four environmental variables: elevation, latitude, soil type, and vegetation impact the relative abundance of Peromyscus maniculatus and the species richness of small mammal populations in Eastern Nevada. In order to complete this study, a survey of small mammals was completed in the following 8 Eastern Nevada valleys: Delamar, Dry Lake, Dry Lake- Muleshoe,Cave, Lake, Snake, Spring, White River. In each valley, transects of Sherman live traps will be set up for 3 consecutive nights (O'Farrell et al 1977). Data on elevation, latitude, soil type, and vegetation were taken at each trap …


Anaerobic Digester Use In Dairy Farms In The United States, Shaun Elsasser May 2006

Anaerobic Digester Use In Dairy Farms In The United States, Shaun Elsasser

UNLV Theses, Dissertations, Professional Papers, and Capstones

Anaerobic digestion is a highly efficient process, trapping the methane gas from cow manure and processing it into energy. The steep initial capital costs make anaerobic digesters short-term liabilities, but the long-term benefits far outweigh the long-term costs. An anaerobic digester unit will begin to show a profit after approximately five years of operation. During the lifetime of the unit, estimated at 15 years, the digester will have produced about $ 1,000,000 in profits for the dairy farm, while also providing invaluable benefits to society as a whole.


The Fate And Transport Of Nitrogen (N) And The Effect Of Emergent Plants On Natural Treatment Of N-Species At Las Vegas Wash, Nevada, Tanju Kiriscioglu May 2006

The Fate And Transport Of Nitrogen (N) And The Effect Of Emergent Plants On Natural Treatment Of N-Species At Las Vegas Wash, Nevada, Tanju Kiriscioglu

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study is to analyze the effect of emergent plant communities at Las Vegas Wash (the System) using a system dynamics modeling approach. Understanding the dynamics of nitrogen (N —major polluting nutrient in the Wash) that enters the System is important because it occasionally causes algal blooms, choking Lake Mead through excessive eutrophication. Emergent plant communities are an integral part of wetland ecosystems and they play a crucial role in natural treatment of nutrients. This study is intended to test this hypothesis.

The study makes use of Wash data from reliable sources (Las Vegas Valley Water District, …


Assessing The Relationships Between The Spatial Variation In Land-Use Spatial Patterns And Surface Water Quality, Majed A. Khater Dec 2005

Assessing The Relationships Between The Spatial Variation In Land-Use Spatial Patterns And Surface Water Quality, Majed A. Khater

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this dissertation was to examine the association between the spatial patterns of urban land uses and surface water quality parameters at the watershed outlet. The aim of the study was to understand the strength and nature of this relationship, and examine new methods of classifying and quantifying contributing urban land-uses and their spatial patterns. The hypothesis of this research was: in an urban watershed, the variation in the spatial patterns of contributing land uses will have a significant impact on the surface water quality parameters at the watershed outlet.

This relationship between urbanization and water quality is …


Observed Omnivory In The Herbivorous Blue Tilapia (Oreochromis Aureus), Stephen M. Oliveira Jr. May 2005

Observed Omnivory In The Herbivorous Blue Tilapia (Oreochromis Aureus), Stephen M. Oliveira Jr.

UNLV Theses, Dissertations, Professional Papers, and Capstones

Gila seminuda, a native endangered species, and Oreochromis aureus, a nonnative invasive species, share the same habitat in the form of the Reid Gardner Power Plant intake ponds. The purpose of this study is to characterize the feeding habits of Oreochromis aureus within the Reid Gardner Power Plant intake ponds and address the potential predation habits of Oreochromis aureus. Stomach contents of O. aureus were identified and analyzed using chi-square and log-likelihood ratio techniques, with respect to mass, length, girth, gender, or spatial distribution of samples. Results showed omnivorous behavior with a 7.00% predatory/prey relationship, and no difference of feeding …


Habitat Preferences Of Four Species Of Lizards Found At The Las Vegas Springs Preserve, Scott Garncarz May 2004

Habitat Preferences Of Four Species Of Lizards Found At The Las Vegas Springs Preserve, Scott Garncarz

UNLV Theses, Dissertations, Professional Papers, and Capstones

Developing an understanding of the habitat usage of reptiles is important when trying to develop a management or restoration plan that is compatible with what is known of the reptile species that are being investigated. There are many lizard species found in the Mojave Desert, but there are only four known to inhabit the Las Vegas Springs Preserve (LVSP) in Las Vegas, Nevada. In the LVSP, sites are going to be restored with native Mojave Desert vegetation. Since there are many habitat types in the Mojave Desert, we must determine which types would be best suited for the four species …


Defining Soil Type And Habitat Characteristics Of The Arctomecon Californica, Philip S. Childers Apr 2004

Defining Soil Type And Habitat Characteristics Of The Arctomecon Californica, Philip S. Childers

UNLV Theses, Dissertations, Professional Papers, and Capstones

A. californica can be considered a rare endemic species, which is believed to be restricted by unique soil relationships. These relationships make the species vulnerable to anthropogenic habitat disturbance. Although A. californica is listed as critically endangered by the state of Nevada, further research is needed before the species can be listed as federally endangered or threatened. This study used primary observational data and secondary GIS compatible data to characterize A. californica habitat. Representative sampling techniques were used to select observations from derived soil types. Although a majority of A. californica populations were found to occur in gypsic soil types, …


Effects Of Residential Xeriscape Conversions On Property Values: A Baseline Case Study, Andréa E. Baker Jan 2004

Effects Of Residential Xeriscape Conversions On Property Values: A Baseline Case Study, Andréa E. Baker

UNLV Theses, Dissertations, Professional Papers, and Capstones

The conversion of grass lawns to xeriscape has become more prevalent in the desert Southwest, including here in the Las Vegas Valley. The purpose of this thesis was to determine whether the conversion of residential landscapes from grass lawn to xeriscape influences the property value of a home. This case study involved the comparison of property values for residential homes that had participated in the Southern Nevada Water Authority’s Water Smart Landscapes rebate program and non-participant homes with similar amenities before and after the landscape conversion. The results of the analysis show that xeriscape dose have a potentially positive impact …


A Waste Assessment Of The Unlv Dormitories, Colin Kaneda May 2003

A Waste Assessment Of The Unlv Dormitories, Colin Kaneda

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this thesis is the examine the waste stream of the UNLV dormitories to see if there is a significant amount of waste than can be diverted through a possible recycling program to lower disposal costs. Also with this data we can look at if the student monitored program in the Upper Classmen Complex dormitories is having any effect on the waste stream. This was done through a waste assessment which is where garbage is sorted and weighed by categories. This study found that 35% of the waste stream is recyclable. This data was compared to the national …


Consumptive Water Use At The Mirage Hotel And The Mandalay Bay Resort & Casino In Las Vegas, Nevada, Johann A. Feller May 2003

Consumptive Water Use At The Mirage Hotel And The Mandalay Bay Resort & Casino In Las Vegas, Nevada, Johann A. Feller

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Las Vegas Valley is one of the driest regions in the southwest United States. Due to limited water supplies from the Colorado River, rainfall, and groundwater sources, the water requirements of the valley’s growing population is slated to surpass the current available water supply. The purpose of this comparative study is to quantify the amount of consumptive water used at a major Las Vegas resort/casino in one year. This, being of importance, because of the resort/casino industry’s role as one of the largest, most visible, and most resource intensive industries in the Las Vegas valley. The goal of this …


Trail Conditions And Preferences From A Mountain Bike Users Perspective In Cottonwood Valley, Jeff Frampton Apr 2003

Trail Conditions And Preferences From A Mountain Bike Users Perspective In Cottonwood Valley, Jeff Frampton

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to gather baseline data and user preferences from a mountain bike user’s perspective about the current condition of the multiple use trails in Cottonwood Valley. Cottonwood Valley is an area located at the southern tip of the Red Rock Canyon National Conservation Area. Multiple use includes hiking, biking and horseback riding and does not include motorized vehicles. The area was set aside for conservation by an act of Congress because of the inherent value that it represents.

Because the public is allowed to access and use the trails in the area, there has been …