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A Long-Term Control Project For An Invasive Plant: Assessment Of Phragmites Australis Reduction And Redevelopment Of Native Vegetation In Interdunal Swales Of Sandy Neck Barrier Beach, Cape Cod, Massachusetts, Dena Tomassi

Biology Masters Theses Collection

Phragmites australis is a perennial wetland grass that is native to North America. However, salt marshes, estuaries, and other wetlands throughout the northeast USA and Canada have witnessed a dramatic range expansion and population increase of the introduced genetic variant Phragmites australis haplotype M (Saltonstall 2002), with loss of native vegetation through competitive exclusion. Within the dune system of Sandy Neck Barrier Beach, freshwater wetland swales form in low elevation areas, which harbor a diverse wetland plant community dominated by shrubs, and sedges -- and including some rare and endangered species. To conserve and protect these wetland plant associations, annual …

Role Of Belowground Fungal Mutualisms And Nutrient Cycling Alteration In Invasion Success Of Polygonum Cuspidatum Sieb. & Zucc. (Polygonaceae) In The Eastern United States, Gretchen Addington

All Theses

Plant species invasion is problematic around the world due to its negative effects on native plant biodiversity, ecosystem function, and ecosystem stability. Understanding the mechanisms of plant species invasion is necessary to predict new invasions and to control current problematic species. Polygonum cuspidatum Sieb. & Zucc. (Polygonaceae, Japanese Knotweed) is an invasive species found in 40 of the 50 United States and listed as a noxious species in nine states. It is known to exclude native plant communities, and its eradication is nearly impossible. The extensive negative effects associated with this species make understanding its mechanism of invasion a prerogative. …

Variable Helper Effects, Ecological Conditions, And The Evolution Of Cooperative Breeding In The Acorn Woodpecker, Walter D. Koenig, Eric L. Walters, Joseph Haydock

Biological Sciences Faculty Publications

The ecological conditions leading to delayed dispersal and helping behavior are generally thought to follow one of two contrasting scenarios: that conditions are stable and predictable, resulting in young being ecologically forced to remain as helpers (extrinsic constraints and the habitat saturation hypothesis), or that conditions are highly variable and unpredictable, leading to the need for helpers to raise young, at least when conditions are poor (intrinsic constraints and the hard life hypothesis). We investigated how variability in ecological conditions influences the degree to which helpers augment breeder fitness in the cooperatively breeding acorn woodpecker (Melanerpes formicivorus), a …

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 …

Historical Diversification Of Montane Herpetofauna Within And Between The Sierras Of Mexico, Robert William Bryson Jr.

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Mexican highlands consist of four major mountain ranges spanning most of mainland Mexico. The evolutionary history of the Mexican highlands has been shaped by various geological and climatic events over the past several million years. The relative impacts of these historical events on diversification in montane taxa, however, remains uncertain. I used mitochondrial DNA data from three widely distributed species complexes of lizards as a model system to exemplify the potential roles of Neogene mountain formation and Quaternary climate change on timing and tempo of diversification across the Mexican highlands. My results suggested strong geographic partitioning of genetic variation …

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

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 …

Land Cover And Topographic Effects On Cavity-Nesting Owl Occurrence And The Role Of Species Interactions In Structuring Cavity-Nesting Owl Communities, Micah Noel Scholer

Boise State University Theses and Dissertations

Relatively little is known about the distribution, abundance, and population trends of many species of owls. Frequently, studies that describe owl distributions are accomplished by modeling characteristics of the habitat such as land cover and topographic features. However, the potential to model owl distributions as a function of species interactions has been largely unexplored. I investigated how habitat characteristics as well as species interactions shape owl distributions in the Western United States. Using occurrence data collected between 2009 and 2010 in the Boise National Forest, Idaho, I developed species distribution models for Flammulated Owls (Otus flammeolus) and Northern …

Phylogeography Of A Vanishing North American Songbird: The Painted Bunting (Passerina Ciris), Connie Ann Herr

UNLV Theses, Dissertations, Professional Papers, and Capstones

Studies of genetic variation within and between species can provide insights into their evolutionary history as well as important information for conserving biodiversity. An understanding of population processes can assist in the conservation of biodiversity by contrasting current versus historical patterns, and the processes that have generated these patterns. Genetic differentiation often coincides with significant geological or climatic changes that have shaped the sizes and locations of the species geographic range and altered the connectivity between populations over time. Phylogenetic and population genetic analyses can also provide a statistical framework for the investigation of how human processes such as habitat …

Dissolved And Colloidal Element Transport Through The Coastal Transition Zone, Moo Joon Shim

Dissertations

There are several factors (e.g., hurricanes, floodplain, and anthropogenic sources) that could modify trace element behavior through the coastal transition zone (CTZ). However, there is still a lack of information about these variables in affecting trace elements in the CTZ. For this study, water samples were collected in the Pearl River (PR), Bay of St. Louis (BSL), and the Mississippi River plume to study the effects of these factors on trace element.

A possible effect of Hurricane Katrina on water quality was examined in the East Pearl River (EPR). Hurricane Katrina could have resulted in increased inputs of organic matter …

Mycorrhizal Colonization Of Native Salt Marsh Plants On Mississippi's Gulf Coast And The Effects Of Commercial Mycorrhizal Inoculants On Nursery-Grown Plants, Kathryn Rondot Mcbride

Master's Theses

Salt marshes are important economically and ecologically to the Gulf Coast and other coasts worldwide. Due to human activities, many coastal salt marshes have been degraded or destroyed. Restoration efforts, through the replacement or addition of naturally occurring salt marsh plants, are taking place worldwide. Most restoration plants are raised in nurseries and are not ready for transfer to restoration sites for eight or nine months. Once the plants are at the restoration site many die due to transplant stress. Arbuscular Mycorrhizal Fungi (AMF) may be able to shorten the time the restoration plants need to stay in the nursery …

An Analytical Study Of Air-Sea Co2 Gas Exchange In The Northwest Mississippi Bight Region, Andrea Kathryn Braatz

Master's Theses

With the continued increase of carbon dioxide (CO2) emissions, researchers are concerned with accumulation of excess CO2 within the atmosphere. The ocean is an important sink for the drawdown of atmospheric CO2 concentrations. Due to high spatial and temporal variability, CO2 fluxes in the coastal ocean are not as well characterized as those for the open ocean. More specifically, data for the northern Gulf of Mexico (GOM) coastal region is lacking. A time series analysis of air-sea CO2 flux rates from May through December 2009 was conducted using data collected by The University of Southern Mississippi’s Central Gulf Ocean Observing …

How Do Human Disturbance, Beach Characteristics, And Coastal Engineering Affect Snowy Plover (Charadrius Alexandrinus) Habitat Selection On The Florida Panhandle?, Alyson F. Webber

Boise State University Theses and Dissertations

Snowy plovers (Charadrius alexandrinus) are listed as threatened by the State of Florida, and have been a species of growing concern among wildlife management agencies. The population of snowy plovers breeding along the Florida Panhandle has a patchy distribution, and large stretches of private and public land go virtually unused by plovers. Further, there is a strong negative correlation between coastal engineering projects and snowy plover nest site use. The relationship between coastal engineering and snowy plover nesting distribution is unclear, however, because most engineering projects have occurred on developed beaches with high human use. My objectives were …

Community Level Effects Of Vegetation Architecture And Prey Availability: A Study Of Ground-Dwelling Arthropods In A Shrub-Steppe Ecosystem, Mary E. Pendergast

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Changes to vegetation architecture within a natural habitat can have profound impacts upon ecological community function, but the relative influence of vegetation architecture itself and potential indirect influences of associated food resources are often difficult to disentangle. I present the results of a three-year study designed to address the community level impacts of changes in big sagebrush (Artemisia tridentata) architecture and associated prey availability upon the ground-dwelling arthropod community. Three experimental sagebrush architecture treatments (low, intermediate, and high foliage density) and two levels of prey insect availability treatment (natural and baited/increased prey availability) were imposed in a sage-steppe …

Effects Of Non‐Surface‐Disturbing Treatments For Native Grass Revegetation On Cheatgrass (Bromus Tectorum L.) Metrics And Soil Ion Availabilities, Jan C.R. Summerhays

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Several restoration methods intended to increase the success of aerially‐seeded perennial grasses were assessed to determine their effects on cheatgrass metrics and soil nutrient bioavailabilities. These methods were: 1) imazapic herbicide application (140 g ai ∙ ha^-1, 210 g ai ∙ ha^-1, and no application [control]), 2) vegetation manipulation treatments (50% sagebrush overstory thinning, 100% sagebrush overstory thinning, sagebrush overstory and/or vegetative thatch burning, and no manipulation [control]), and 3) alternative seeding treatments (aerial seeding with raking, aerial seeding with activated carbon [AC] addition, aerial seeding with sucrose addition, and regular aerial seeding [control]). Treatments were …

A Mathematician Weighs In On The Evolution Debate, Kris H. Green

Journal of Humanistic Mathematics

There are a variety of reasons underlying the lack of public acceptance for the theory of evolution in the United States. An overlooked cause is related to problems with the mathematics curriculum in the K-12 setting. In this essay, we examine this relationship and propose changes to the mathematics curriculum that could improve mathematical thinking while also providing a basis for understanding theories, like evolution, that are poorly understood.

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

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 …

Systematics Of African Skink In The Panaspis Wahlbergi Complex, Ma. Fernanda Medina^, Eli Greenbaum*

COURI Symposium Abstracts, Summer 2011

No abstract provided.

Survival, Breeding Frequency, And Migratory Orientation In The Jefferson Salamander, Ambystoma Jeffersonianum, Stephen P. De Lisle, Kristine L. Grayson

Biology Faculty Publications

Accurate estimates of demographic parameters, such as survival and breeding frequency, are necessary for the conservation and management of animal populations. Additionally, life-history data are required for gaining an empirical understanding of the ecology of natural populations. We monitored a population of Jefferson Salamanders (Ambystoma jeffersonianum) breeding in a permanent mountain-top pond at the southern limit of this species’ geographic range in Virginia over four years. We used closed multistate mark-recapture models with Pollock's robust design to estimate the demographic parameters of this population. Additionally, we used point-of-capture data to compare the orientation of migrations into and out …

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 …

How Well Do U.S. Forest Service Terrestrial Ecosystem Surveys Correspond With Measured Vegetation Properties?, Scott R. Abella

Life Sciences Faculty Research

No abstract provided.

Satellite Finds Highest Land Skin Temperatures On Earth, David J. Mildrexler, Maosheng Zhao, Steven W. Running

Ecosystem and Conservation Sciences Faculty Publications

The location of the hottest spot on Earth has undoubtedly been an interesting curiosity for centuries. Even with the advent of the instrumental temperature record around the year 1850, the location of the hottest spot on Earth has continued to be the subject of debate and controversy. In 1913, the weather station at Furnace Creek in Death Valley National Park, California, measured an air temperature of 56.7°C (134.1°F) and claimed the title of “hottest place on Earth.” Nine years later in El Azizia, Libya, an air temperature of 57.8°C (136°F) was recorded on land owned by an Italian farmer and …

The Distribution And Life Cycle Of Alliaria Petiolate In Lincoln, Nebraska, Caleb Pharris

Department of Environmental Studies: Undergraduate Student Theses

Alliaria petiolata (Garlic Mustard) is a biennial alien invasive plant species of the Brassicacea family. It is responsible for displacing native plant species throughout North America and its management has proven to be extremely difficult. Recently several populations of Alliaria petiolata have been discovered in southwestern Lincoln, Nebraska. The spread of Alliaria petiolata is a concern for natural resource managers and the general public. Due to the difficulty of its control, Alliaria petiolata is capable of creating monocultures which diminish the aesthetic value of an ecosystem. While most commonly found in the understory of hardwood forests, it is capable of …

The Effects Of Arbuscular Mycorrhizal (Am) Fungal And Garlic Mustard Introductions On Native Am Fungal Diversity, Alexander M. Koch, Pedro M. Antunes, Kathryn Barto, Don Cipollini, Daniel L. Mummey, John N. Klironomos

Biological Sciences Faculty Publications

Introduced, non-native organisms are of global concern, because biological invasions can negatively affect local communities. Arbuscular mycorrhizal (AM) fungal communities have not been well studied in this context. AM fungi are abundant in most soils, forming symbiotic root-associations with many plant species. Commercial AM fungal inocula are increasingly spread worldwide, because of potentially beneficial effects on plant growth. In contrast, some invasive plant species, such as the non-mycorrhizal Alliaria petiolata, can negatively influence AM fungi. In a greenhouse study we examined changes in the structure of a local Canadian AM fungal community in response to inoculation by foreign AM fungi …

Techniques To Promote Garry Oak Seedling Growth And Survival In Areas With High Levels Of Herbivory And Competition, David R. Clements, Seth Luginbill, David A. Jordan, Randall Dragt

University Faculty Publications and Creative Works

Though regeneration of Garry oak (Quercus garryana) seedlings within Garry oak ecosystems is important to maintain this threatened habitat, seedling regeneration is often poor. Two independent studies were initiated in the early 2000s to examine questions surrounding Garry oak recruitment: one at the Crow's Nest Ecological Research Area (CNERA) on Salt Spring Island, BC, and another at the Pacific Rim Institute for Environmental Stewardship (PRI) on Whidbey Island, WA. In both areas, Garry oak seedlings were caged and monitored for growth and relative health. Over 8 years at CNERA, growth of caged plants outpaced growth of controls, which was indicative …

Herbicide-Resistant Risk Assessment: Response Of Common Nebraska Weeds To Dicamba Dose, Roberto J. Crespo

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Dicamba-resistant soybeans are being developed to provide an additional herbicide mechanism of action that can be used in soybean, and to provide a tool to help manage or mitigate the evolution of other herbicide-resistant weed populations. The objectives of this thesis were to assess the risk of common Nebraska weeds developing resistance to dicamba, quantify baseline dose-response to dicamba of high-risk weed species, and survey the variability in dicamba dose-response among populations of those species. Twenty-five weed scientists were asked to estimate the risk likelihood of ten weed species evolving resistance to dicamba following the commercialization of dicamba-resistant soybean. Palmer …

Mojave Applied Ecology Notes Summer 2011, Scott R. Abella, Charles W. Denton, David G. Brewer, Rory W. Steinke, Wayne A. Robbie, W. Wallace Covington, E. Cayenne Engel, Ross Guida

Mojave Applied Ecology Notes

Thoughts on fire possibilities on Mount Charleston, estimating historical densities of Ponderosa pine in northern AZ, over-understory changes in the Spring Mountains, seeding effectiveness in Red Rock Canyon, workshop announcements.

Patterns Of Transience, Sex Bias, And Body Mass In Open-Habitat Rodent Populations, Stephen Edward Rice

Biological Sciences Theses & Dissertations

Rodents are assumed to live their lives in circumscribed (natal) areas with males being more prone to disperse than females and juveniles more prone to disperse than adults. To test these assumptions we examined the initial captures of geographic populations of hispid cotton rat, meadow vole, prairie vole, and marsh rice rat obtained through capture-mark-recapture methods. Capture records were obtained from Kansas and Illinois from long-term studies, and through live-trapping in Chesapeake, Virginia. I evaluated proportions of residents and transients, adults and juveniles, and males and females for significant differences among seasons, years, and geographic locations. The overall body masses …

Phylogeography Of The Reef Fish Cephalopholis Argus(Epinephelidae) Indicates Pleistocene Isolation Across The Indo-Pacific Barrier With Contemporary Overlap In The Coral Triangle, Michelle R. Gaither, Brian W. Bowen, Tiana-Rae Bordenave, Luiz A. Rocha, Stephen J. Newman, Juan A. Gomez, Lynne Van Herwerden, Matthew T. Craig

Fisheries Research Articles

Background

The Coral Triangle (CT), bounded by the Philippines, the Malay Peninsula, and New Guinea, is the epicenter of marine biodiversity. Hypotheses that explain the source of this rich biodiversity include 1) the center of origin, 2) the center of accumulation, and 3) the region of overlap. Here we contribute to the debate with a phylogeographic survey of a widely distributed reef fish, the Peacock Grouper (Cephalopholis argus; Epinephelidae) at 21 locations (N = 550) using DNA sequence data from mtDNA cytochrome b and two nuclear introns (gonadotropin-releasing hormone and S7 ribosomal protein).

Results

Population structure was significant …