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Avian Influenza In Migratory Birds In The United States, 2007–2009, And Effects Of September Hunting Seasons On Survival, Harvest, And Recovery Rates Of Canada Geese Banded In Southeast Nebraska, Scott R. Groepper Aug 2011

Avian Influenza In Migratory Birds In The United States, 2007–2009, And Effects Of September Hunting Seasons On Survival, Harvest, And Recovery Rates Of Canada Geese Banded In Southeast Nebraska, Scott R. Groepper

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

Highly-pathogenic avian influenza virus (HPAIV H5N1) poses risks to wild birds, poultry, and humans. Personnel with the United States Department of Agriculture-Animal Plant Health Inspection Service-Wildlife Services, state, and tribal wildlife agencies collected 168,940 samples from migratory birds from 2007 to 2009 to test for presence of HPAIV H5N1. No HPAIV was found, but other subtypes were discovered, including H5 and H7. I estimated prevalence of avian influenza virus by flyway and found prevalence was lowest each year in the Atlantic Flyway (6.7%–8.3%), highest in the Pacific Flyway in 2007 (13.3%) and 2008 (13.4%), and highest in the Mississippi Flyway …


Using Slow-Release Permanganate To Remove Tce From A Low Permeable Aquifer At A Former Landfill, Mark D. Christenson Aug 2011

Using Slow-Release Permanganate To Remove Tce From A Low Permeable Aquifer At A Former Landfill, Mark D. Christenson

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

Past disposal of industrial solvents into unregulated landfills is a significant source of groundwater contamination. In 2009, we began investigating a former unregulated landfill with known trichloroethene (TCE) contamination. Our objective was to pinpoint the location of the plume and treat the TCE using in situ chemical oxidation (ISCO). We accomplished this by using electrical resistivity imaging (ERI) to survey the landfill and map the subsurface lithology. We then used the ERI maps to guide direct push groundwater sampling. A TCE plume (100-600 µg L-1) was identified in a low permeable silty-clay aquifer (Kh = 0.5 m …


Climate And Vegetation Change In The Newberry Mountains, Southern Clark County, Nevada, Ross Joseph Guida Aug 2011

Climate And Vegetation Change In The Newberry Mountains, Southern Clark County, Nevada, Ross Joseph Guida

UNLV Theses, Dissertations, Professional Papers, and Capstones

Ecological studies have shown worldwide that vegetation is being affected by climate change. Species are shifting to new elevations and physiographic positions to adapt to changes in their environment. More specifically, paleoecology studies in the Mojave Desert have shown shifting vegetation patterns in response to past warming and precipitation changes. Recent studies have shown mortality among desert plants related to extended drought and warming. However, few studies have shown how the geographic distribution of Mojave Desert species has changed during this most recent period of warming. This study addresses this gap in the literature by focusing on several plant species …


Biological Condition Of Money Pont Benthic Communities, Southern Branch Of The Elizabeth River (2010), Daniel M. Dauer Aug 2011

Biological Condition Of Money Pont Benthic Communities, Southern Branch Of The Elizabeth River (2010), Daniel M. Dauer

Elizabeth River Reports

Executive Summary

The subtidal macrobenthic communities off Money Point in the Southern Branch of the Elizabeth River were quantitatively sampled in summer 2011. The designated Money Point study area will be a part of a sediment contaminant remediation effort. The primary objectives of this study were to: (1) characterize the biological health of the benthos of Money Point and (2) produce an historical data base that will allow an assessment of the effectiveness of the proposed sediment contamination remediation efforts with respect to Money Point benthos.

The most quantitative characterization of the benthos of the Elizabeth River watershed was the …


Environmental Magnetism Survey Of A Holocene Sedimentary Record From Barilari Bay, Western Antarctic Peninsula, Carl Joseph Natter Jr. Aug 2011

Environmental Magnetism Survey Of A Holocene Sedimentary Record From Barilari Bay, Western Antarctic Peninsula, Carl Joseph Natter Jr.

Theses, Dissertations and Culminating Projects

Barilari Bay is located on the western side of the Antarctic Peninsula (AP), opposite the former Larsen B Ice Shelf on the eastern Antarctic Peninsula. Barilari Bay was swath mapped during United States Antarctic Program cruise NBP10-01 as part of the Larsen Ice Shelf System, Antarctic (LARISSA) program. The bay consists of a series of five basins with water depths greater than 600 meters, from which a suite of kasten cores and jumbo piston cores was collected. Three cores, JPC-127, its trigger core TC- 127, and JKC 55 were collected from the outer portion of the Bay and recovered an …


Groundwater Contamination Potential In Northern Nevada From Mining, Associated Communities, And Agriculture As Forecasted By Two Vulnerability Methods, John L. Swatzell Aug 2011

Groundwater Contamination Potential In Northern Nevada From Mining, Associated Communities, And Agriculture As Forecasted By Two Vulnerability Methods, John L. Swatzell

UNLV Theses, Dissertations, Professional Papers, and Capstones

Two methodologies, DRASTIC and the NDEP method, were used to compare the groundwater vulnerability of mining, associated towns, and agricultural areas in northern Nevada. The DRASTIC and NDEP methods were compared to determine which method produces a more accurate depiction of vulnerability. Vulnerability maps were created using the United States Environmental Protection Agency's (USEPA) DRASTIC and Nevada Department of Environmental Protection (NDEP) methodologies. The DRASTIC map uses seven aspect layers of geologic and hydrologic information with assigned values and weights that are applied to a mathematical equation. The NDEP method uses field data collection for potential contaminant sources and well …


Redefining Security In Sub-Saharan Africa, Winta Sintayehu Gebremariam Aug 2011

Redefining Security In Sub-Saharan Africa, Winta Sintayehu Gebremariam

UNLV Theses, Dissertations, Professional Papers, and Capstones

New and challenging threats to humans are currently on the rise. These threats to human well being have been neglected and ignored within the traditional conception of security. Security studies have mainly focused on traditional threats, mostly military and political. Although still important, this perspective lacks the ability to address nontraditional threats that are killing and injuring millions each year. Each year, millions die of diseases such as HIV/AIDS, tuberculosis, malaria, hunger, and water related diseases among others. Although these threats are widespread throughout the world, Sub-Saharan Africa bears the brunt of these threats. This thesis proposes an ecological approach …


Time-Dependent Crack Growth Behavior Of Alloy 617 And Alloy 230 At Elevated Temperatures, Shawoon Kumar Roy Aug 2011

Time-Dependent Crack Growth Behavior Of Alloy 617 And Alloy 230 At Elevated Temperatures, Shawoon Kumar Roy

UNLV Theses, Dissertations, Professional Papers, and Capstones

Two Ni-base solid-solution-strengthened superalloys: INCONEL 617 and HAYNES 230 were studied to check sustained loading crack growth (SLCG) behavior at elevated temperatures appropriate for Next Generation Nuclear Plant (NGNP) applictaions with constant stress intensity factor (K max = 27.75 MPa[checkmark]m) in air. The results indicate a time-dependent rate controlling process which can be characterized by a linear elastic fracture mechanics (LEFM) parameter - stress intensity factor (K). At elevated temperatures, the crack growth mechanism was best described using a damage zone concept. Based on results and study, SAGBOE (stress accelerated grain boundary oxidation embrittlement) is considered the primary reason for …


Aiding Conservation Of The Federally Threatened Scutellaria Montana (Lamiaceae, Large-Flowered Skullcap) Through Abundance Monitoring And Transplantation Studies, Heather Mae Kile Aug 2011

Aiding Conservation Of The Federally Threatened Scutellaria Montana (Lamiaceae, Large-Flowered Skullcap) Through Abundance Monitoring And Transplantation Studies, Heather Mae Kile

Masters Theses and Doctoral Dissertations

Scutellaria montana Chapm. (large-flowered skullcap) is a federally threatened species endemic to Georgia and Tennessee. This thesis presents conservation work on this species through abundance monitoring at a single site in Catoosa County, Georgia, and transplantation experiments at two sites located in Hamilton County, Tennessee, and Catoosa County, Georgia. Plants naturally occurring in the fixed plots surveyed over seven years had an overall stable growth status, though relatively low floral induction and seedlings. Transplantation revealed influences of abiotic and biotic factors. One transplantation site was fenced to prevent human trampling and apparently discouraged vertebrate grazing, resulting in dramatic flower number …


Ecologically-Based Manipulation Practices For Managing Bromus Tectorum-Infested Rangelands, Beth Fowers Aug 2011

Ecologically-Based Manipulation Practices For Managing Bromus Tectorum-Infested Rangelands, Beth Fowers

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Cheatgrass (Bromus tectorum) is an invasive annual grass common in several semiarid plant communities in the western U.S. B. tectorum presence increases fire frequency and size, reducing species diversity, and leading to annual species-dominated systems with inconsistent livestock forage potential and degraded wildlife habitat value. Most efforts to manage B. tectorum-dominated rangelands have focused on controlling the plant itself rather than addressing the causes of vegetation change. An alternative approach, ecologically-based invasive plant management (EBIPM), identifies treatments that can alter factors associated with the causes of succession, leading to a more desirable vegetation state. This study utilized …


Technical Assistance For The Revision Of The Conservation Agreement For The Spring Mountains National Recreation Area: Final Closeout Report, Public Lands Institute Jul 2011

Technical Assistance For The Revision Of The Conservation Agreement For The Spring Mountains National Recreation Area: Final Closeout Report, Public Lands Institute

Public Lands Institute Publications

Technical Assistance for the revision of the Conservation Agreement for the Spring Mountains National Recreation Area was cooperative agreement between the U.S. Fish and Wildlife Service (USFWS) and the Board of Regents of the Nevada System of Higher Education. The cooperator was the Public Lands Institute (PLI) of the University of Nevada, Las Vegas (UNLV) working directly with staff of the USFWS Southern Nevada Field Office and the U.S. Forest Service’s (USFS) Humboldt-Toiyabe National Forest. The mechanism of cooperation was a Cooperative Ecosystem Studies Unit (CESU) Task Agreement. The purpose of the project was to provide technical assistance to the …


Impact Of Alternative Range Management Systems On Grasslands In The Central Platte River Valley, Nebraska, Luis E. Ramirez Jul 2011

Impact Of Alternative Range Management Systems On Grasslands In The Central Platte River Valley, Nebraska, Luis E. Ramirez

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

Land management strategies can directly and indirectly affect plant assemblages and their behavior. Little research has been performed in south central Nebraska to quantify the effect of fire and grazing interactions on species composition, vegetation structure, forage quality, and potential cost associated with land management.

I evaluate the effect of season-long continuous, patch-burning, and rotational grazing approaches on vegetation and ranching costs to determine their value as conservation tools. This study includes data collected between 2007 and 2009 from grasslands in south central Nebraska. I found that land management influence plant assemblages by shifting communities when grazing and/or fire are …


Discontinuities: Predicting Invasions And Extinctions, Aaron Lotz Jul 2011

Discontinuities: Predicting Invasions And Extinctions, Aaron Lotz

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

In this dissertation, I explore multiple tenets of the textural discontinuity hypothesis, which states that hierarchical landscape structures with scale-specific pattern entrain attributes of animals inhabiting the landscape. Landscapes form hierarchies that are structured by vegetative, geomorphological and contagious disturbance processes. The spatial and temporal patterns inherent in landscapes reflect numerous processes, interacting on distinct scales, which shape the assembly of animal communities. Analysis of body mass patterns and functional group distributions has been suggested as methods to provide insight about these underlying hierarchical processes. Scientists have posited that species at the edges of body mass aggregations may be exposed …


University-Community Partnerships For Environmental Safety And Sustainability, John W. Vick, Carol Norton Jul 2011

University-Community Partnerships For Environmental Safety And Sustainability, John W. Vick, Carol Norton

Education for Sustainability Summer Institute

No abstract provided.


Outdoor Classroom And Wildlife Habitat Development, Patricia Sowell, Deborah Sherfey, Kandy Fear Jul 2011

Outdoor Classroom And Wildlife Habitat Development, Patricia Sowell, Deborah Sherfey, Kandy Fear

Education for Sustainability Summer Institute

No abstract provided.


Global Climate Change International Collaborations Through Stem And Ee, Teddie Phillipson-Mower, Laurie A. Henry Jul 2011

Global Climate Change International Collaborations Through Stem And Ee, Teddie Phillipson-Mower, Laurie A. Henry

Education for Sustainability Summer Institute

No abstract provided.


Education For Sustainability As A 21st Century Literacy, Nancy Givens Jul 2011

Education For Sustainability As A 21st Century Literacy, Nancy Givens

Education for Sustainability Summer Institute

No abstract provided.


Ecological Profiling Of Bird-Mosquito Interactions In Central Virginia, Anna Riggan Jul 2011

Ecological Profiling Of Bird-Mosquito Interactions In Central Virginia, Anna Riggan

Theses and Dissertations

Current methods of mosquito surveillance estimate general population abundances, but fail to represent the relationship of vector abundance to host density important to determining transmission risk of mosquito-borne pathogens (MBP). We sought to address this limitation by creating a novel mosquito trap that directly sampled mosquitoes seeking to feed on nesting birds. The primary objectives of this study were to (1) assess the efficiency of the Nest Mosquito Trap (NMT) and how this is affected by nest box size. (2) assess whether the NMT affects bird, specifically nest success in Prothonotary Warblers (Protonotaria citrea), and adult behavior. (3) compare our …


Preliminary Assessment Of Hybridization And Introgression Of Morone Species In The Toledo Bend Reservoir, Louisiana, Kelsey L. Daroca Jul 2011

Preliminary Assessment Of Hybridization And Introgression Of Morone Species In The Toledo Bend Reservoir, Louisiana, Kelsey L. Daroca

Honors Capstones

No abstract provided.


Walking Box Ranch Planning And Design Quarterly Progress Report: Period Ending July 10, 2010, Margaret N. Rees Jul 2011

Walking Box Ranch Planning And Design Quarterly Progress Report: Period Ending July 10, 2010, Margaret N. Rees

Walking Box Ranch

  • UNLV participated in several meetings with BLM regarding updating the current Task Order, obtaining a two-year no-cost extension for the two Assistance Agreements, and to develop the future WBR operating agreement between BLM and UNLV
  • UNLV met with Sara Moffatt, one of Senator Reid’s staff, to provide an update on project progress. UNLV also requested the Senator’s support in obtaining additional funding for the project for construction, and also for UNLV to bridge the transition from construction through the first two years of operation.
  • UNLV held several internal meetings to advance planning for a July VA meeting with BLM to …


Growth Of Age-0 Atlantic Menhaden (Brevoortia Tyrannus) In Two Tidal Freshwater Tributaries Of Chesapeake Bay, Peter M. Sturke Jul 2011

Growth Of Age-0 Atlantic Menhaden (Brevoortia Tyrannus) In Two Tidal Freshwater Tributaries Of Chesapeake Bay, Peter M. Sturke

Theses and Dissertations

Few studies have described growth rates of age-0 Atlantic menhaden (Brevoortia tyrannus). Growth rates from tidal freshwater habitats of the Mattaponi and James Rivers, Virginia in 2009 were described and compared using otolith microstructural analyses. Larval tidal freshwater growth rates were significantly faster in the culturally eutrophic James River when compared to those collected from the Mattaponi River (p-value < 0.001). Elevated primary production within tidal freshwater habitats promotes favorable conditions for larval Atlantic menhaden growth. No differences between river habitats for juvenile growth rates were evident. Comparisons of age-0 growth rates to higher salinity habitats indicate that tidal freshwater habitats should be considered essential habitat for age-0 Atlantic menhaden.


Development Of Environmental Tools For Anopheline Larval Control, Susan S. Imbahale, Collins K. Mweresa, Willem Takken, Wolfgang R. Mukabana Jul 2011

Development Of Environmental Tools For Anopheline Larval Control, Susan S. Imbahale, Collins K. Mweresa, Willem Takken, Wolfgang R. Mukabana

All Peer-Reviewed Publications

Background: Malaria mosquitoes spend a considerable part of their life in the aquatic stage, rendering them vulnerable to interventions directed to aquatic habitats. Recent successes of mosquito larval control have been reported using environmental and biological tools. Here, we report the effects of shading by plants and biological control agents on the development and survival of anopheline and culicine mosquito larvae in man-made natural habitats in western Kenya. Trials consisted of environmental manipulation using locally available plants, the introduction of predatory fish and/or the use of Bacillus thuringiensis var. israelensis (Bti) in various combinations. Results: Man-made habitats provided with shade …


Effectiveness Of Forest Management Strategies To Mitigate Effects Of Global Change In South-Central Siberia, Eric J. Gustafson, Anatoly Z. Shvidenko, Robert M. Scheller Jul 2011

Effectiveness Of Forest Management Strategies To Mitigate Effects Of Global Change In South-Central Siberia, Eric J. Gustafson, Anatoly Z. Shvidenko, Robert M. Scheller

Environmental Science and Management Faculty Publications and Presentations

We investigated questions about the ability of broad silvicultural strategies to achieve multiple objectives (reduce disturbance losses, maintain the abundance of preferred species, mitigate fragmentation and loss of age-class diversity, and sequester aboveground carbon) under future climate conditions in Siberia. We conducted a factorial experiment using the LANDIS-II landscape disturbance and succession model. Treatments included varying the size and amount of areas cut and the cutting method (selective or clearcut). Simultaneously, the model simulated natural disturbances (fire, wind, insect out-breaks) and forest succession under projected future climate conditions as predicted by an ensemble of global circulation models. The cutting method …


On The Spatial Heterogeneity Of Net Ecosystem Productivity In Complex Landscapes, Ryan E. Emanuel, Diego Andrés Riveros-Iregui, Brian L. Mcglynn, Howard E. Epstein Jul 2011

On The Spatial Heterogeneity Of Net Ecosystem Productivity In Complex Landscapes, Ryan E. Emanuel, Diego Andrés Riveros-Iregui, Brian L. Mcglynn, Howard E. Epstein

School of Natural Resources: Faculty Publications

Micrometeorological flux towers provide spatially integrated estimates of net ecosystem production (NEP) of carbon over areas ranging from several hectares to several square kilometers, but they do so at the expense of spatially explicit information within the footprint of the tower. This finer-scale information is crucial for understanding how physical and biological factors interact and give rise to towermeasured fluxes in complex landscapes. We present a simple approach for quantifying and evaluating the spatial heterogeneity of cumulative growing season NEP for complex landscapes. Our method is based on spatially distributed information about physical and biological landscape variables and knowledge of …


Turning Students Into Problem Solvers, Larkin A. Powell, Andrew J. Tyre, Michael J. Conroy, James T. Peterson, B. Ken Williams Jul 2011

Turning Students Into Problem Solvers, Larkin A. Powell, Andrew J. Tyre, Michael J. Conroy, James T. Peterson, B. Ken Williams

School of Natural Resources: Faculty Publications

In the popular movie Apollo 13, based on the actual NASA mission, three astronauts are stranded in space, their craft’s electrical system broken, their oxygen quickly running out. To help them fix the problem and return home safely, mission controllers summon a group of engineers, dump a pile of equipment onto a desk—the tools available to the astronauts—and tell them to find a solution, or more specifically, “a way to put a square peg in a round hole. Rapidly.” Eventually, the engineers’ plan saves the day, and the astronauts make it home.

State and federal agency biologists generally do …


Planning Approaches For Water Resources Development In The Lower Mekong Basin, Robert Costanza, Ida Kubiszewski, Peter Paquet, Jeffrey King, Shpresa Halimi, Hansa Sanguanngoi, Nguyen Luong Bach, Richard Frankel, Jiragorn Ganaseni, Apisom Intralawan, David Morell Jul 2011

Planning Approaches For Water Resources Development In The Lower Mekong Basin, Robert Costanza, Ida Kubiszewski, Peter Paquet, Jeffrey King, Shpresa Halimi, Hansa Sanguanngoi, Nguyen Luong Bach, Richard Frankel, Jiragorn Ganaseni, Apisom Intralawan, David Morell

Institute for Sustainable Solutions Publications and Presentations

Governments in the Lower Mekong Basin (LMB) face decisions that involve trade-offs between, for example, the economic benefits from hydropower generation and potentially irreversible negative impacts on the ecosystems that provide livelihoods and food security to the rural poor. These decisions involve complex problems that are both poorly understood in scientific terms and subject to rapid, potentially catastrophic change over time. A comprehensive, whole systems approach that adequately addresses the risks and uncertainties involved is necessary, but this is a daunting challenge for researchers, decision makers, and managers. They must develop the capacity to plan, coordinate, and implement a program …


Cedar Infestation Impacts Avian Communities Along The Niobrara River Valley, Nebraska, January S. Frost, Larkin A. Powell Jul 2011

Cedar Infestation Impacts Avian Communities Along The Niobrara River Valley, Nebraska, January S. Frost, Larkin A. Powell

School of Natural Resources: Faculty Publications

Habitat modification has the potential to cause changes in structure and composition of bird communities. Our goal was to determine the response of Songbird community composition to eastern red cedar (Juniperus virginiana) removal in The Nature Conservancy’s Niobrara Valley Preserve, Nebraska. We used point counts to survey birds in the riparian matrix of grassland and forest habitats. More than 60 species were recorded on surveys during 2004–2005. We also use the program PRESENCE to determine the response of five species to various habitat components, including cedar density: House Wren (Troglodytes aedon), Spotted Towhee (Pipilo maculates …


Scwds Briefs: Volume 27, Number 2 (July 2011), Jeanenne Brewton, Michael J. Yabsley Jul 2011

Scwds Briefs: Volume 27, Number 2 (July 2011), Jeanenne Brewton, Michael J. Yabsley

Southeastern Cooperative Wildlife Disease Study: Publications

Guilty Deer Breeder Fined $1,500,000

EHDV-7 Research at SCWDS

Jack Crockford

Gary Doster Retires, Again

Time to Move On

Recent SCWDS Publications Available


Water Current, Volume 43, No. 3, Summer 2011 Jul 2011

Water Current, Volume 43, No. 3, Summer 2011

Water Current Newsletter

Fall Water Law Conference and Great Plains Climate and Ecosystems

Lenton Named to Head NU's Daughterty Institute

Meet the Faculty: Michael W. Van Liew, Ph.D., James W. Schneider

Advisory Panel Formed, Fall Conference and Symposium Planned

Water Center Empanels New Advisory Board

Rapid Changes in Greenland Climate Over Last 5,000 Years, Study Says

Missouri River Flooding and UNL Extension Response

Be Patient, Cautious When Dealing with 2011 Flood

Summer 2011 Flooding on the Missouri and Platte Rivers

2011 Missouri River Flood: A Nested Matryoshka Doll

Forest Service Map Bolsters Watershed Health

Web Resources for Tracking Flow and Flood Conditions in …


A Study On Facility Planning Using Discrete Event Simulation: Case Study Of A Grain Delivery Terminal, Sarah M. Asio Jul 2011

A Study On Facility Planning Using Discrete Event Simulation: Case Study Of A Grain Delivery Terminal, Sarah M. Asio

Department of Industrial and Management Systems Engineering: Dissertations, Theses, and Student Research

The application of traditional approaches to the design of efficient facilities can be tedious and time consuming when uncertainty and a number of constraints exist. Queuing models and mathematical programming techniques are not able to capture the complex interaction between resources, the environment and space constraints for dynamic stochastic processes. In the following study discrete event simulation is applied to the facility planning process for a grain delivery terminal. The discrete event simulation approach has been applied to studies such as capacity planning and facility layout for a gasoline station and evaluating the resource requirements for a manufacturing facility. To …