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Relationships Of Exotic Plant Invasions With Biological Soil Crust, Desert Pavement, And Soil Carbon In The Eastern Mojave Desert, Adria Decorte May 2011

Relationships Of Exotic Plant Invasions With Biological Soil Crust, Desert Pavement, And Soil Carbon In The Eastern Mojave Desert, Adria Decorte

UNLV Theses, Dissertations, Professional Papers, and Capstones

In a matter of 50 years, exotic annual plants have become widespread in the Mojave Desert, contributing to drastic landscape changes such as those caused by recent fires. Invasions by exotics threaten native Mojave Desert plant communities by altering community functions (e.g. fire regimes) and by reducing plant diversity. Because it is not practical, or even possible, to eradicate these exotics, developing effective prevention techniques is the key to controlling these invasions.

This thesis used a greenhouse experiment, a field experiment, and a correlational field study to examine the affect soil surface types have on the establishment of three exotic …


A Mark–Recapture Technique For Monitoring Feral Swine Populations, Matthew M. Reidy, Tyler A. Campbell, David G. Hewitt May 2011

A Mark–Recapture Technique For Monitoring Feral Swine Populations, Matthew M. Reidy, Tyler A. Campbell, David G. Hewitt

United States Department of Agriculture Wildlife Services: Staff Publications

Techniques to monitor populations of feral swine (Sus scrofa) relative to damage control activities are needed on rangelands. Our objectives were to describe and assess a mark–recapture technique using tetracycline hydrochloride (TH) for monitoring feral swine populations. We established bait stations at study sites in southern and central Texas. During 1 d, we replaced normal soured corn bait with bait containing TH and counted the number of feral swine that consumed bait with observers. We conducted feral swine removal using box-style traps and helicopters, at which time we collected teeth for TH analysis. In southern Texas, we estimated …


How Defining Planetary Boundaries Can Transform Our Approach To Growth, W. L. Steffen, Johan Rockström, Robert Costanza May 2011

How Defining Planetary Boundaries Can Transform Our Approach To Growth, W. L. Steffen, Johan Rockström, Robert Costanza

Institute for Sustainable Solutions Publications and Presentations

The article focuses on the importance to identify safe boundaries based on the fundamental characteristics of our planet to address the growing threats of climate change. It highlights the rapid transition of the planet from the stable Holocene state to an unknown future state of significantly different conditions. In addition, climate change, biodiversity loss and phosphorus production were already transgressed by humanity and require innovative frameworks and effective solutions.


Multiple And Long-Term Effects Of An Introduced Predatory Crab, Catherine E. De Rivera, Edwin D. Grosholz, Gregory M. Ruiz May 2011

Multiple And Long-Term Effects Of An Introduced Predatory Crab, Catherine E. De Rivera, Edwin D. Grosholz, Gregory M. Ruiz

Environmental Science and Management Faculty Publications and Presentations

Despite the importance of invasions, few studies have explored their long-term consequences in marine systems or examined multiple types of population-level effects. Initial effects, however, may not persist over longer time frames; effects have been shown to wane in freshwater systems. We combined 14 yr of field surveys (1993 to 2006) with manipulative experiments to examine the potential for multiple effects of a nonindigenous crab Carcinus maenas on the native shore crab Hemigrapsus oregonensis over time in central California. H. oregonensis abundance was negatively correlated with C. maenas abundance. However, H. oregonensis abundance rebounded to pre-invasion levels once C. maenas …


Growing The Urban Ecosystem In Detroit, Michigan, Sean Basalyga May 2011

Growing The Urban Ecosystem In Detroit, Michigan, Sean Basalyga

Social Sciences

Many views of the future are seen as bleak and devoid of the life where once stood beauty and abundance. However, the Living Cities Design Competition challenges these views and calls for a vision of the future that inspires hope, biodiversity, and a healthy interaction between human and natural systems. We chose to redesign the city of Detroit, Michigan to be a living city by the year 2035. As the earth scientist on an interdisciplinary team, I acted as an ecological consultant. By developing the urban ecosystem of Detroit, a number of social, economical, and environmental problems can be solved. …


Great Salt Lake Watershed: Its Role In Maintaining The Wetlands Of The Great Salt Lake, Danny C. White Jr. May 2011

Great Salt Lake Watershed: Its Role In Maintaining The Wetlands Of The Great Salt Lake, Danny C. White Jr.

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

The following bioregional planning study is a direct result of the 2009- 2010 studio project initiated by the United States Fish and Wildlife Service (FWS). The FWS contacted the study team and asked them to determine how the future growth and development of the Bear River Watershed would impact the Bear River Migratory Bird Refuge (BRMBR). The study looked at all of the physical and biophysical systems within the Bear River Watershed to identify the issues that had an effect on the BRMBR.

It became apparent from the original project that the future of the BRMBR and other Great Salt …


Biodiesel Production Using Chemical And Enzymatic Catalysts And Improvement Of Cold Flow Properties Using Additives, Hem Joshi May 2011

Biodiesel Production Using Chemical And Enzymatic Catalysts And Improvement Of Cold Flow Properties Using Additives, Hem Joshi

All Dissertations

Biodiesel production was carried out from soybean, canola and cottonseed oils along with poultry fat using catalytic potassium hydroxide. Further, the physical properties of biodiesel were studied with addition of ethyl levulinate (ethyl 4-oxopentanoate), short-chain alcohols (ethanol, isopropanol and butanol), and commercial cold flow improver (CFI) additives. The effects of adding ethyl levulinate, short-chain alcohols, and commercial additives were determined by studying their influence on the acid value (AV), cloud point (CP), pour point (PP), cold filter plugging point (CFPP), induction period (IP), kinematic viscosity (KV) and the flash point (FP). The results showed improved low temperature properties of the …


Process-Based Management Of Downy Brome In Salt Desert Shrublands: Assessing Pre- And Post- Rehabilitation Soil And Vegetation Attributes, Merilynn Carol Hirsch May 2011

Process-Based Management Of Downy Brome In Salt Desert Shrublands: Assessing Pre- And Post- Rehabilitation Soil And Vegetation Attributes, Merilynn Carol Hirsch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As an ecosystem driver, downy brome (Bromus tectorum L.) presents obstacles to land rehabilitation efforts, including restoring desirable species cover. Because damaged ecosystems may have crossed both abiotic and biotic thresholds, ecologically-based control strategies may assist with altering successional trajectories and restoring desirable plant species. My thesis research had three objectives: 1) assess soil and vegetation relationships in degraded salt desert ecosystems prior to implementing downy brome control treatments, 2) determine the effects of control treatments on soil properties and resident plant species, and 3) evaluate the relative importance of shrubland soil type, herbicide type, and herbicide rate on seedling …


Alternative Futures For The Upper Colorado River Ecosystem: Phase Ii, Temis G. Taylor May 2011

Alternative Futures For The Upper Colorado River Ecosystem: Phase Ii, Temis G. Taylor

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

Wildlife habitat and biodiversity in the Upper Colorado River Ecosystem are threatened by growth of urban areas, subdivision of rural lands, and exploitation of natural resources. The White-Yampa, Colorado Headwaters, and Gunnison River Watersheds within the region were investigated to discover areas supporting high biodiversity that would be possible candidates for conservation efforts by the U.S. Fish and Wildlife Service. Using an alternative futures planning process and principles of landscape ecology, development of energy of the resources in the region was found to be the primary driver for land use and impacts to wildlife habitat. Through application of geospatial modeling …


Effectiveness Of Earthtec ® On Killing Invasive Quagga Mussels (Dreissena Rostriformis Bugenis) And Preventing Their Colonization In The Western U.S., Ashlie Watters May 2011

Effectiveness Of Earthtec ® On Killing Invasive Quagga Mussels (Dreissena Rostriformis Bugenis) And Preventing Their Colonization In The Western U.S., Ashlie Watters

UNLV Theses, Dissertations, Professional Papers, and Capstones

Dreissena rostriformis bugensis, an invasive species, also known as the quagga mussel, was discovered in Lake Mead, NV in January of 2007. In the four years since detection, quagga mussels have created tremendous economical, ecological, and human health impacts. The mussels clog pipes, ruin boat motors, and damage recreational equipment, and once established in the lake, routine maintenance is necessary to avoid further damage. Because of quagga mussels' high fecundity, planktonic veliger stage, and ability to attach to substrates with byssal threads, they have easily and swiftly spread to other lakes and reservoirs in the Lower Colorado River Basin. …


Consensus On The Colorado: Issues In The Allocation Of A Limited Resource, Jeffrey D. Tilton May 2011

Consensus On The Colorado: Issues In The Allocation Of A Limited Resource, Jeffrey D. Tilton

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to identify current issues in water allocation in the Lower Colorado River Basin and to locate existing areas of consensus among its stakeholders. Surveys, both paper and web-based provided the data required to measure overwhelming agreement on issues. The data analysis served to locate the areas of agreement within and between interest groups. While overwhelming agreement between all groups proved to be a relatively rare occurrence, the existence of issue specific agreement between two or more groups was more common than expected. Accord was demonstrated in all four major areas: allocation, augmentation, conservation, and …


Planning For Building-Integrated Agriculture In Las Vegas, Robert Vralsted May 2011

Planning For Building-Integrated Agriculture In Las Vegas, Robert Vralsted

UNLV Theses, Dissertations, Professional Papers, and Capstones

High food prices, concern about food nutrition and safety, and an awareness of commercial farming's environmental impact have generated a renewed interest in sustainable urban agriculture. Advances in controlled environment agriculture (CEA) have made it possible to grow food virtually anywhere in a much more sustainable manner than traditional field-based agriculture. Locating and planning urban farms using retrofitted existing building stock to maximize food production and ease of distribution in Las Vegas requires consideration of multiple barriers related to geography, economics, and the built environment. Consideration of these factors in the planning process informs the design of a successful BIA …


Colonization And Decontamination Of Quagga Mussels In The Western United States: Monitoring Veligers In Lake Mead And Field Testing In The Effects Of Hot-Water Spray As A Means Of Watercraft Decontamination, Sean Robin Comeau May 2011

Colonization And Decontamination Of Quagga Mussels In The Western United States: Monitoring Veligers In Lake Mead And Field Testing In The Effects Of Hot-Water Spray As A Means Of Watercraft Decontamination, Sean Robin Comeau

UNLV Theses, Dissertations, Professional Papers, and Capstones

The introduction and establishment of aquatic invasive species (AIS) is one of the top causes of global biodiversity loss and ecological change, and is also financially costly for taxpayers and agencies managing protected areas. This is especially true regarding the nationwide spread of dreissenid mussels to various bodies of freshwater. The discovery of invasive quagga mussels (Dreissena rostriformis bugensis) in Lake Mead on January 6, 2007 has changed the popular recreation area into a potential vector of the destructive AIS. This location could allow for an increased spread of these dressenid species to uninfested bodies of water in the western …


A Statistical Model For Long-Term Forecasting Of Strong Sand Dust Storms, Siqi Tan May 2011

A Statistical Model For Long-Term Forecasting Of Strong Sand Dust Storms, Siqi Tan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Dust elevated into the atmosphere by dust storms has numerous environmental consequences. These include contributing to climate change; modifying local weather conditions; producing chemical and biological changes in the oceans; and affecting soil formation, surface water, groundwater quality, crop growth, and survival (Goudie and Middleton, 1992). Societal impacts include disruptions to air, road and rail traffic; interruption of radio services; the myriad effects of static-electricity generation; property damage; and health effects on humans and animals (Warner, 2004).

In this thesis, we extend the idea of empirical recurrence rate (ERR), developed by Ho (2008), to model the temporal trend of the …


Impacts Of Climate Change And Weather Modification On Hydrologic Characteristics Of Watersheds In The Western United States, Anil Acharya May 2011

Impacts Of Climate Change And Weather Modification On Hydrologic Characteristics Of Watersheds In The Western United States, Anil Acharya

UNLV Theses, Dissertations, Professional Papers, and Capstones

This research quantifies the impacts of climate change and weather modification (WM) on hydrologic characteristics of watersheds in the arid regions of the western United States. This research performs a long-term simulation of streamflow for present and future climate conditions in the North Platte (NP) Watershed, Wyoming; a shorter duration simulation is then performed to observe the likely impacts of event based changes in an urban watershed in Las Vegas, Nevada.

First, a study is carried out in Chapter 3 that evaluates the impacts of WM on water supply by developing a hydrologic model for the NP Watershed. The variable …


Association Of Oceanic-Atmospheric Oscillations And Hydroclimatic Variables In The Colorado River Basin, Ajay Kalra May 2011

Association Of Oceanic-Atmospheric Oscillations And Hydroclimatic Variables In The Colorado River Basin, Ajay Kalra

UNLV Theses, Dissertations, Professional Papers, and Capstones

With increasing evidence of climatic variability, there is a need to improve forecast for hydroclimatic variables i.e., precipitation and streamflow preserving their spatial and temporal variability. Climatologists have identified different oceanic-atmospheric oscillations that seem to influence the behavior of these variables and in turn can be used to extend the forecast lead time. In the absence of a good physical understanding of the linkages between oceanic-atmospheric oscillations and hydrological processes, it is difficult to construct a physical model. An attractive alternative to physically based models are the Artificial Intelligence (AI) type models, also referred to as machine learning or data-driven …


An Ecological Study Of Peregrine Falcons (Falco Peregrinus) At Lake Mead National Recreation Area, 2006-2010, Joseph Graham Barnes May 2011

An Ecological Study Of Peregrine Falcons (Falco Peregrinus) At Lake Mead National Recreation Area, 2006-2010, Joseph Graham Barnes

UNLV Theses, Dissertations, Professional Papers, and Capstones

Peregrine Falcons (Falco peregrinus) represent an encouraging conservation biology success story in North America during the twentieth century. Their distribution and population size suffered major restrictions after the initiation of widespread application of the synthetic pesticide dichloro-diphenyl-trichloroethane (DDT) within the U.S. in the 1940s. The species was federally listed as endangered in the U.S. in 1969 and was then delisted in 1999 after DDT was banned in 1972. Herein, I present my ecological research of peregrines within Lake Mead National Recreation Area (LMNRA), concentrating on the years 2006-2010. This thesis is comprised of two chapters. In the first chapter, I …


Understanding Bioprospecting: Can Indigenous Populations Benefit From The Search For Pharmaceuticals In Areas Of High Biodiversity, Emily Schwindt May 2011

Understanding Bioprospecting: Can Indigenous Populations Benefit From The Search For Pharmaceuticals In Areas Of High Biodiversity, Emily Schwindt

Department of Environmental Studies: Undergraduate Student Theses

Bioprospecting is a controversial issue, and anthropologists and other scientists are quick to take sides. The idea of large corporations pumping money into conservation and development programs, while developing what could be the latest life-saving drug simply sounds too good to be true, and often times is. However, if all parties work together and proceed with caution, these benefits could become more than a fantasy. Looking at case studies from Costa Rica, India, South Africa and Panama this paper attempts to find patterns among successful bioprospecting agreements and note shortcomings and identify risks. This information will be used to suggest …


The Diffusion Of Environmental Literacy In An American Urban Community Through Children, Kelley Phillips May 2011

The Diffusion Of Environmental Literacy In An American Urban Community Through Children, Kelley Phillips

Department of Environmental Studies: Undergraduate Student Theses

Environmental literacy is a contentious issue in the United States of America because citizens feel it is forced upon them and interferes with our materialistic culture. Also, many Americans have limited access to green space and little time to devote to increasing their environmental mindset. This project documents a technique to introduce environmental literacy to American citizens by working with single communities in a common subset of American culture. Based on a model used by anthropologists in third world countries, the goal was to diffuse environmental literacy into a community by only instructing the children of that community in environmental …


Educating Young Adults About Sustainable Development, Meghan Lewis May 2011

Educating Young Adults About Sustainable Development, Meghan Lewis

Department of Environmental Studies: Undergraduate Student Theses

This qualitative study on the types of environmental education on different age groups was conducted in Lincoln, Nebraska. The purpose of this thesis is to identify what age group and educational methods would be most effective to educate Lincoln citizens on the importance and benefits of sustainable development. Environmental education is an important aspect in implementation of new, environmentally friendly ideas.

Lincoln environmentalists are working to improve the city’s sustainability. Finding a way to consistently educate Lincoln residents on the importance and benefits of sustainable development will increase the public’s awareness of their efforts, leading to a greater interest in …


Parks And Obesity In Rural And Urban Nebraska, Michaela S. Wolf May 2011

Parks And Obesity In Rural And Urban Nebraska, Michaela S. Wolf

Department of Environmental Studies: Undergraduate Student Theses

In order to better understand the role community design plays in obesity rates, this project studies a potential relationship between distance of parks from homes and obesity rates in four Nebraska counties. Park use may contribute to important health benefits, such as reducing risk of obesity by increasing physical activity levels. There are limitations to park use, such as crime rates and facility upkeep that are important to understand so that they might be managed and communities can reap greater benefits from their parks, including better fitness. This study examines park distance from homes as a potential limiting factor to …


A Contribution To The Vascular Flora Of The Sequatchie Valley Within Sequatchie County, Tennessee, John Richard Evans May 2011

A Contribution To The Vascular Flora Of The Sequatchie Valley Within Sequatchie County, Tennessee, John Richard Evans

Masters Theses and Doctoral Dissertations

The vascular flora of the Sequatchie Valley within Sequatchie County, Tennessee was studied for three growing seasons from 2008 through 2010. The Sequatchie Valley is located within the southeastern portion of the Cumberland Plateau and is generally considered to be part of the Cumberland Plateau Physiographic Province. Nevertheless, a number of geological and ecological factors distinguish the Sequatchie Valley from the elevated Cumberland Plateau, suggesting that the floristic composition of the valley may be different from the surrounding region. Although several previous floristic studies have been conducted on the plateau surface, very little attention has been given to the Sequatchie …


Testing The Utility Of The Consortium For The Barcoding Of Life's Two 'Agreed Upon' Plant Dna Barcodes, Matk And Rbcl, Iam Michael Cohen May 2011

Testing The Utility Of The Consortium For The Barcoding Of Life's Two 'Agreed Upon' Plant Dna Barcodes, Matk And Rbcl, Iam Michael Cohen

Masters Theses and Doctoral Dissertations

DNA barcoding is the use of short standardized regions of DNA to identify unknown specimens to species. Currently, the zoological community has agreed that cytochrome oxidase I subunit 1 (COI), a mitochondrial gene region, will serve as the barcode region for all animal taxa. Due to oftentimes complicated evolutionary histories of plants, the plant barcoding community has had a much harder time agreeing on a gene region or regions that should be used to barcode the various land plant lineages. This is in large part due to poor reproductive barriers, which allows for chloroplast sharing between closely related species. In …


Feasibility Study Of Carbon Offsets As A Source Of Revenue For A Land Trust Using The Climate Action Reserve's Avoided Conversion Protocol, Jennifer Marie Sexton May 2011

Feasibility Study Of Carbon Offsets As A Source Of Revenue For A Land Trust Using The Climate Action Reserve's Avoided Conversion Protocol, Jennifer Marie Sexton

Masters Theses and Doctoral Dissertations

In 2008, 279 million hectares of forest land contained 45,337 teragrams (Tg) of carbon. Changes in land use and forestry practices in 2008 resulted in a net carbon sequestration of 940.3 Tg of carbon dioxide equivalent, or 13.5% of total U.S. greenhouse gas emissions in 2008, making forests a net sink for carbon. With increasing development pressures, organizations such as land trusts, that protect forest land and prevent deforestation, are positioned to become key players in climate change mitigation. There are 21 land trusts in Tennessee protecting over 165,000 acres of land. One such land trust, the Tennessee River Gorge …


Phytoremediation Of Pcb Contaminated Soil: Effectiveness And Regulatory Policy, Nathan Pinsker Apr 2011

Phytoremediation Of Pcb Contaminated Soil: Effectiveness And Regulatory Policy, Nathan Pinsker

Theses and Dissertations

The purpose of this paper was to combine available peer-reviewed literature on PCB phytoremediation and make direct comparisons using ANCOVA statistics in order to determine if and what plants are presently a viable option for the remediation of PCB contaminated soils. Pumpkin (Curbita pepo cv Howden) consistently had the top root and shoot concentrations, as well as total plant accumulation. Their consistency shows that they can be reliable in the field and the most viable option. Tall fescue and sedge were also top contenders. Due to the small sample size for many plants and accounting for several confounding variables, very …


Burr’S Pond And Runnins River Annual Watershed Survey, 2011 Apr 2011

Burr’S Pond And Runnins River Annual Watershed Survey, 2011

Watershed Access Lab Projects

For the past ten years, AP Biology students at Seekonk High School have been required to complete an independent research project to fulfill the Ecology unit of the course during the summer prior to the course. Students must apply what they learned in their readings to a local ecosystem, Burr’s Pond, which is attached to the Runnins River. Students spend time at the pond area during the summer documenting organisms, evidence of population dynamics, animal behavior, trophic levels, nutrient cycling, etc. Students put together a Burr’s Pond Summer Field Research Project Portfolio to be submitted on the first day of …


The Runnins River Biosurvey Apr 2011

The Runnins River Biosurvey

Watershed Access Lab Projects

Fall 2010 marks the third year that all 10th grade Biology II students and their teachers joined the watershed study project initiated by AP Biology students at Seekonk High School. The students traveled to two sites, one upstream and one downstream, along the Runnins River, which is a river that meanders through the Town of Seekonk. The upstream site was located at the home of the Masons off of Woodward Ave and the downstream site was located just below Burr’s Pond, both in Seekonk. The four Biology II classes were split between the two site locations and it was their …


Furnace Brook Stream Study Apr 2011

Furnace Brook Stream Study

Watershed Access Lab Projects

No abstract provided.


Timing Of Seasonal Migration In Mule Deer: Effects Of Climate, Plant Phenology, Andlife-History Characteristics, Kevin L. Monteith, Vernon C. Bleich, Thomas R. Stephenson, Becky M. Pierce, Mary M. Conner, Robert W. Klaver, R. Terry Bowyer Apr 2011

Timing Of Seasonal Migration In Mule Deer: Effects Of Climate, Plant Phenology, Andlife-History Characteristics, Kevin L. Monteith, Vernon C. Bleich, Thomas R. Stephenson, Becky M. Pierce, Mary M. Conner, Robert W. Klaver, R. Terry Bowyer

Wildland Resources Faculty Publications

Phenological events of plants and animals are sensitive to climatic processes. Migration is a life-history event exhibited by most large herbivores living in seasonal environments, and is thought to occur in response to dynamics of forage and weather. Decisions regarding when to migrate, however, may be affected by differences in life-history characteristics of individuals. Long-term and intensive study of a population of mule deer (Odocoileus hemionus) in the Sierra Nevada, California, USA, allowed us to document patterns of migration during 11 years that encompassed a wide array of environmental conditions. We used two new techniques to properly account for interval-censored …


Super-Aggregations Of Krill And Humpback Whales In Wilhelmina Bay, Antarctic Peninsula, Douglas P. Nowacek, Ari S. Friedlaender, Patrick N. Halpin, Elliott L. Hazen, David W. Johnston, Andrew J. Read, Boris Espinasse, Meng Zhou, Yiwu Zhu Apr 2011

Super-Aggregations Of Krill And Humpback Whales In Wilhelmina Bay, Antarctic Peninsula, Douglas P. Nowacek, Ari S. Friedlaender, Patrick N. Halpin, Elliott L. Hazen, David W. Johnston, Andrew J. Read, Boris Espinasse, Meng Zhou, Yiwu Zhu

Environmental, Earth, and Ocean Sciences Faculty Publication Series

Ecological relationships of krill and whales have not been explored in the Western Antarctic Peninsula (WAP), and have only rarely been studied elsewhere in the Southern Ocean. In the austral autumn we observed an extremely high density (5.1 whales per km2) of humpback whales (Megaptera novaeangliae) feeding on a super-aggregation of Antarctic krill (Euphausia superba) in Wilhelmina Bay. The krill biomass was approximately 2 million tons, distributed over an area of 100 km2 at densities of up to 2000 individuals m−3; reports of such ‘super-aggregations’ of krill have been absent in …