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Wildfire Regime Shifts In Temperate Forest Ecosystems: International Symposium In New Zealand, Tomas Veblen, Alan Tepley, Andres Holz

Joint Fire Science Program Research Project Reports

This project consisted of organizing and executing a one-day symposium on “Wildfire Regime Shifts in Temperate Forest Ecosystems” in conjunction with the triennial meeting of the Southern Connection Congress. The VIIth Southern Connection Congress drew together more than 350 environmental scientists and resource managers for its triennial meeting in Dunedin, New Zealand from January 25 to 30, 2013. The Southern Connection Congress (SCC) is a meeting of interdisciplinary researchers and natural resource managers who are interested in the biota and ecosystems of the temperate latitudes of the southern hemisphere. Attendees are from a wide range of research and professional disciplines …

A National Study Of The Consequences Of Fire And Fire Surrogate Treatments, Phil Weatherspoon, Jim Agee, Phil Aune, Jim Baldwin, Jamie Barbour, Frank Beall, Julio Betancourt, Ralph Boerner, Matt Busse, Carl Edminster, Gary Fiddler, Carl Fiedler, Sally Haase, Kathy Harchsen, Mick Harrington, Ron Hodgson, Sue Husari, Jon Keeley, Mike Landram, Bill Laudenslayer, Jim Mciver, Dan Neary, Bill Otrosina, Roger Ottmar, Martin Ritchie, Kevin Ryan, Patrick Shea, Carl Skinner, Scott Stephens, Nate Stephensen, Elaine Kennedy Sutherland, Bob Vihanek, Dale Wade, Tom Waldrop, Dan Yaussy, Andy Youngblood, Steve Zack

Joint Fire Science Program Research Project Reports

Many U.S. forests, especially those with historically short-interval, low- to moderate-severity fire regimes, are too dense and have excessive quantities of fuels. Widespread treatments are needed to restore ecological integrity and reduce the high risk of destructive, uncharacteristically severe fires in these forests. Among possible treatments, however, the appropriate balance among cuttings, mechanical fuel treatments, and prescribed fire is often unclear. For improved decisionmaking, resource managers need much better information about the consequences of alternative management practices involving fire and mechanicaVmanual "fire surrogates." Long-term, interdisciplinary research thus should be initiated to quantify the consequences and tradeoffs of alternative fire and …

Land Use, Landscapes, And Biological Invasions, Karie L. Decker, Craig R. Allen, Leonardo Acosta, Michelle L. Hellman, Christopher F. Jorgensen, Ryan J. Stutzman, Kody M. Unstad, Amy Williams, Matthew Yans

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The negative effect of invasive species on native species, communities, and ecosystems is widely recognized, and the economic effects in the United States are estimated to be billions of dollars annually. Studies often examine traits of nonnative species or examine what makes a particular habitat invasible. To better understand the factors governing invasions, we used the flora of Nebraska to characterize and compare native and nonnative plant occurrences throughout the state. In addition, we assessed four critical landscape predictors of nonnative plant richness: human population size and three land cover attributes that included percentage of grassland, percentage of agriculture, and …

Long-Term Research On Biodiversity In West Khentey, Northern Mongolia, Michael Mühlenberg

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Biodiversity is studied at ecosystem, community, and species level around Khonin Nuga, where the University Goettingen supports a research station since 15 years (established 1997 in cooperation with the National University of Mongolia). In that period 39 scientists have been involved and 67 students graduated with theses (7 PhD) about field work at that station. Inventories started at 1998 for several taxa and are now compiled in a book, which will be printed 2012 in Ulaanbaatar. It covers fungi, lichens, plants, several insect groups, spiders, crustaceans, and all vertebrate classes. For all taxa adequate experts proved the species lists. Because …

First Stable Isotope Analysis Of Asiatic Wild Ass Tail Hair From The Mongolian Gobi, Micha Horacek, Petra Kaczensky, Merina Burnik Sturm

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Stable isotope analysis has become a powerful tool to study feeding ecology, water use or movement pattern in contemporary, historic and ancient species. Certain hair and teeth grow continuously, and when sampled longitudinally can provide temporally explicit information on dietary regime and movement pattern. In an initial trial, we analysed a tail sample of an Asiatic wild ass (Equus hemionus) from the Mongolian Gobi. We found seasonal variations in H, C, and N isotope patterns, likely being the result of temporal variations in available feeds, water supply and possibly physiological status. Thus stable isotope analysis shows promise to …

Population Estimate Of Chinese Mystery Snail (Bellamya Chinensis) In A Nebraska Reservoir, Noelle M. Chaine, Craig R. Allen, Kent A. Fricke, Danielle M. Haak, Michelle L. Hellman, Robert A. Kill, Kristine T. Nemec, Kevin L. Pope, Nicholas A. Smeenk, Bruce J. Stephen, Daniel R. Uden, Kody M. Unstad, Ashley E. Vanderham

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The Chinese mystery snail (Bellamya chinensis) is an aquatic invasive species in North America. Little is known regarding this species’ impacts on freshwater ecosystems. It is believed that population densities can be high, yet no population estimates have been reported. We utilized a mark-recapture approach to generate a population estimate for Chinese mystery snail in Wild Plum Lake, a 6.47-ha reservoir in southeast Nebraska. We calculated, using bias-adjusted Lincoln-Petersen estimation, that there were approximately 664 adult snails within a 127 m² transect (5.2 snails/m²). If this density was consistent throughout the littoral zone (depth) of …

Spatial Complexity In Fragmenting Amazonian Rainforests: Do Feedbacks From Edge Effects Push Forests Towards An Ecological Threshold?, Graeme S. Cumming, Jane Southworth, Xanic J. Rondon, Matthew Marsik

United States Department of Commerce: Staff Publications

Deforestation and resulting landscape fragmentation are important concerns in many tropical areas. Deforestation is a complex process with many potential feedback loops, many of which are ignored in models that attempt to interpolate forest loss based on past deforestation rates. In addition, most ecological studies of the impacts of deforestation have focused on landscapes that are already fragmented. These studies ignore the fact that edge effects, such as anthropogenic fire, reach their maximum well before habitat connectivity is lost and may create positive feedbacks that result in further fragmentation. We developed a simple model to explore the potential influence of …

Linking Ciguatera Poisoning To Spatial Ecology Of Fish: A Novel Approach To Examining The Distribution Of Biotoxin Levels In The Great Barracuda By Combining Non-Lethal Blood Sampling And Biotelemetry, Amanda C. O'Toole, Marie-Yasmine Dechraoui Bottein, Andy J. Danylchuk, John S. Ramsdell, Steven J. Cooke

United States Department of Commerce: Staff Publications

Ciguatera in humans is typically caused by the consumption of reef fish that have accumulated Ciguatoxins (CTXs) in their flesh. Over a six month period, we captured 38 wild adult great barracuda (Sphyraena barracuda), a species commonly associated with ciguatera in The Bahamas. We sampled three tissues (i.e.,muscle, liver, and blood) and analysed them for the presence of ciguatoxins using a functional in vitro N2A bioassay. Detectable concentrations of ciguatoxins found in the three tissue types ranged from 2.51 to 211.74 pg C-CTX-1 equivalents/ g. Blood and liver toxin concentrations were positively correlated (ρ=0.86, P=0.003), indicating …

Analysis And Synthesis Of Metadata Goals For Scientific Data, Craig Willis, Jane Greenberg, Hollie C. White

Faculty Scholarship

The proliferation of discipline-specific metadata schemes contributes to artificial barriers that can impede interdisciplinary and transdisciplinary research. The authors considered this problem by examining the domains, objectives, and architectures of nine metadata schemes used to document scientific data in the physical, life, and social sciences. They used a mixed-methods content analysis and Greenberg’s (2005) metadata objectives, principles, domains, and architectural layout (MODAL) framework, and derived 22 metadata-related goals from textual content describing each metadata scheme. Relationships are identified between the domains (e.g., scientific discipline and type of data) and the categories of scheme objectives. For each strong correlation …

Gene Transcription In Sea Otters (Enhydra Lutris); Development Of A Diagnostic Tool For Sea Otter And Ecosystem Health, Lizabeth Bowen, A. Keith Miles, Michael Murray, Martin Haulena, Judy Tuttle, William Van Bonn, Lance Adams, James L. Bodkin, Brenda Ballachey, James A. Estes, M. Tim Tinker, Robin Keister, Jeffrey L. Stott

United States Geological Survey: Staff Publications

Gene transcription analysis for diagnosing or monitoring wildlife health requires the ability to distinguish pathophysiological change from natural variation. Herein, we describe methodology for the development of quantitative real-time polymerase chain reaction (qPCR) assays to measure differential transcript levels of multiple immune function genes in the sea otter (Enhydra lutris); sea otter-specific qPCR primer sequences for the genes of interest are defined. We establish a ‘reference’ range of transcripts for each gene in a group of clinically healthy captive and free-ranging sea otters. The 10 genes of interest represent multiple physiological systems that play a role in immuno-modulation, …

The Impact Of Solar Radiation On The Distribution Of The Red Imported Fire Ant, Solenopsis Invicta (Hymenoptera: Formicidae), Audrey Marie Hernando

Open Access Theses & Dissertations

This dissertation investigates the role of solar radiation on Solenopsis invicta, the red imported fire ant. This ant is considered a serious invasive pest in the southern United States. Four Texas cities where fire ants are found were studied: San Antonio, Corpus Christi, Wichita Falls, and the outlier, Lubbock. Shade angles were measured in eight compass directions within plots located along eight transect directions around buildings. Using the shade angle, solar radiation for different times of day and seasons were calculated. All of the cities were on the same precipitation isocline with the exception of Lubbock, Texas. The number of …

Disparities In Park Availability, Features, And Characteristics By Social Determinants Of Health Within A U.S.-Mexico Border Urban Area, Amir Kamel

Open Access Theses & Dissertations

Background: Parks have been shown to be a key feature in the built environment that promote physical activity and positively influence health. However, a number of studies have highlighted that park availability, park features (e.g., park facilities, amenities, and aesthetic features), and park characteristics (e.g., quality/safety concerns of the park and surrounding neighborhood) are not equally distributed across neighborhoods in the U.S, specifically areas of low socioeconomic status and diverse racial/ethnic composition. The overall aim of this study was to examine and describe park availability, park features, and park characteristics, and determine their association with two social determinants of health …

The Impact Of Decadal Land Cover Change On The Global Warming Potential Of Beringian Arctic Tundra, David Hwei-Len Lin

Open Access Theses & Dissertations

Arctic terrestrial ecosystems play an important role in the global carbon cycle. If arctic warming continues to rise as projected, large amounts of soil carbon stored in these ecosystems could be released to the atmosphere as carbon dioxide or methane and positively enhance greenhouse warming. Thus, improving understanding of the likely future state and fate of arctic soil carbon, and the carbon uptake potential of arctic terrestrial ecosystems are well recognized research priorities.

At the pan-arctic scale, decadal increases in NDVI (Normalized Difference Vegetation Index), an index of vegetation productivity, have been observed from satellite imagery, indicating a general greening …

An Assessment Of Land Cover Change At The Indio Mountains Research Station, Rebecca Anne Escamilla

Open Access Theses & Dissertations

Land cover change is a significant contributor to environmental change on a global scale. In the arid regions of the southwest US, shrub encroachment is one of the most important forms of land cover change. Many factors contribute to shrub encroachment, which can impact structure and function. In the Chihuahuan Desert, mountain ecosystems are known as biodiversity hotspots and are especially susceptible to environmental change making them useful indicators of global change. The overarching goal of this dissertation is to improve i) understanding of land cover change in a Chihuahuan Desert mountain landscape, and ii) how knowledge of land cover …

Management In A Neotropical Show Cave: Planning For Invertebrates Conservation, Thais Giovannini Pellegrini, Rodrigo Lopes Ferreira

International Journal of Speleology

Lapa Nova is a dolomitic cave about 4.5 km long located in northwestern Minas Gerais state, Brazil. The cave experiences intense tourism, concentrated over a single period of the year, during the Feast of Our Lady of Lapa. In order to evaluate the impacts felt by the invertebrate community from this tourism, a new methodology was proposed. Four types of areas (intense visitation area, outlying visitation areas, moderate visitation areas and no-visitation areas) were sampled for invertebrates. There was one sampling prior and another on the last day of the 128^th feast, to evaluate the effects of visitation on …

Δ13c Is A Signature Of Light Availability And Photosynthesis In Seagrass, Xingping Hu, David J. Burdige, Richard C. Zimmerman

OES Faculty Publications

We explored the role of light-saturated (carbon-limited) photosynthesis on δ¹³C of turtlegrass (Thalassia testudinum Banks ex Konig) populations from the clear, blue waters of the Great Bahama Bank and the turbid, green waters of Florida Bay using field observations and radiative transfer models. Consistent with numerous previous observations, leaf δ¹³C decreased significantly with water depth in both regions. However the δ¹³C for Bahamas turtlegrass was 3 parts per thousand heavier than that for Florida Bay turtlegrass at equivalent depths, and broadband irradiance explained even less of the δ¹³C variations than depth. Instead, leaf δ¹³C showed a stronger relationship to …

Mangroves, Mudbanks And Seawalls: Political Ecology Of Adaptation To Sea Level Rise In Suriname, Ravic Nijbroek

USF Tampa Graduate Theses and Dissertations

This study seeks to understand how global discourses of sea level rise (SLR) and mangrove ecology influence national climate change adaptation policy to reduce coastal vulnerability in Suriname. A majority of the Surinamese population lives along the low elevation coastal zone and is highly exposed to projected SLR. Failure by the international community to reach agreement on climate change mitigation means that vulnerable coastal communities must adapt. The Suriname coast is predominantly shaped by mudbanks and mangroves which together provide protection against coastal erosion and trap sediments resulting in coastal accretion. Knowledge claims of mangrove ecology and utility in SLR …

A Systems Approach To Ecological Economic Models Developed Progressively In Three Interwoven Articles, Takuro Uehara

Dissertations and Theses

My dissertation develops and analyzes ecological economic models to study the complex dynamics of an ecological economic system (EES) and investigate various conditions and measures which can sustain a developing economy over the long term in view of resilience and sustainability. Because of the intrinsic complexity of the system, I take a systems approach, using economics as the foundation for the basic structure of an ecological economic model, and system dynamics as the method to build and analyze such a complex ecological economic model. Throughout my dissertation, the model developed by Brander and Taylor (1998) is adopted as a baseline …

Sustainability Education As A Framework For Enhancing Environmental Stewardship In Young Leaders: An Intervention At Tryon Creek Nature Day Camp, Andrea Nicole Lawrence

Dissertations and Theses

UNESCO established Sustainability Education as a top priority when it declared 2005 - 2014 to be the global decade for sustainability. Sustainability education can be implemented in outdoor programs such as nature summer camps in order to build environmental stewardship and ecological literacy in counselors and campers. This study sought to determine the extent to which an ecology and leadership training given to assistant counselors at Tryon Creek State Natural Area day camp achieved the goals of sustainability education--for the assistant counselors to learn about ecology, develop stewardship attitudes and behaviors toward the environment, and become positive role models for …

The Distribution And Diversity Of Functional Gene Pathways Controlling Sulfur Speciation In Lower Kane Cave, Wyoming, Audrey Tarlton Paterson

LSU Master's Theses

Defining the linkages between microbial metabolic activity and environmental geochemistry can be used to understand how carbonate dissolution in sulfidic karst systems proceeds. In Lower Kane Cave, Wyoming, sulfidic springs support taxonomically distinct microbial communities that are also associated with putative sulfur metabolisms (e.g., oxidation of reduced sulfur compounds, sulfate reduction, and sulfur disproportionation) that influence carbonate dissolution. The distribution of diverse microbial groups in other terrestrial subsurface environments is not well understood, making Lower Kane Cave ideal for study. Molecular genetics techniques were used to uncover diversity of 16S rRNA genes and bacterial soxB and aprA functional genes. Aqueous …

Biomass And Mass Balance Isotope Content Of Mussel Seep Populations, Philip Martin Riekenberg

LSU Master's Theses

Cold seep mussels, Bathymodiolus childressi, are common cold seep constituents that form large populations at upper continental slope (500-1000 m) cold seep sites in the Northern Gulf of Mexico. These mussels utilize methane present through symbiotic relationships with methanotrophic bacteria. This study uses a coupled isotope technique to determine the relative incorporation of respiratory carbon in the shell as a measure of the availability of methane between different seep sites. This method indicates a higher abundance of methane at the Brine Pool site than at the Bush Hill site which appears significantly more resource limited and that changes in methane …

Function And Diversity Of The Ship, Trinity, And Tiger Shoal Complex, With Emphasis On Macrofauna And Spawning Blue Crabs (Callinectes Sapidus), Carey George Gelpi Jr.

LSU Doctoral Dissertations

The ecological and economic value of sandy shoals off the Louisiana coast is not well understood. During three years of comprehensive benthic sampling and environmental measurements I studied the Ship, Trinity, Tiger Shoal Complex (STTSC), which comprises changing and discrete benthic habitats including high relief sandy shoals, and muddier, mostly deeper off-shoal areas, prone to hypoxia. Benthic macrofaunal assemblages of shoals included endemic species, and shoal communities were significantly different from each other and the muddier offshoal habitat, contributing to northern Gulf of Mexico (GoM) regional biodiversity. Sand percentage was the most influential environmental parameter shaping macrofaunal community composition across …

Genetic Structure Of Grass Carp Populations In The Missouri And Mississippi River Basins, Usa, Bobbi M. Adams, Katie N. Bertrand, Michael L. Brown, Donald Auger

The Prairie Naturalist

We provided an early characterization of the genetic structure of the grass carp (Ctenopharyngodon idella) population as it expands its distribution in both the Missouri and Mississippi River basins. Further, we provided initial comparisons of allelic richness at 17 polymorphic microsatellite markers between 56 grass carp from the USA, and six from the Yangtze River in China. The number of alleles per locus ranged from two to eight and size ranges of alleles for fish collected from the invaded and native ranges were similar (P ≤ 0.001; 107–226 bp) to those previously reported in the literature. Distance-based clustering …

Bryoecology In The American Southwest: Patterns Of Biodiversity And Responses To Global Change, John Carroll Brinda

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation combines investigation of the large-scale responses of bryophyte species diversity and distribution with small-scale physiological adaptations to global change. These two areas of inquiry are linked because one way to predict plant species responses to global change is to examine their distribution across current ecological gradients produced by factors such as latitude and elevation. By examining these biogeographic patterns one can identify those species that have a narrow tolerance and therefore are most sensitive to change. Selected bryophytes might then be used as indicator species in long-term monitoring programs. Where historical data exist, these can be used to …

Being Outside Learning About Science Is Amazing: A Mixed Methods Study, Michelle L. Weibel

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study used a convergent parallel mixed methods design to examine teachers' environmental attitudes and concerns about an outdoor educational field trip. Converging both quantitative data (Environmental Attitudes Scale and teacher demographics) and qualitative data (Open-Ended Statements of Concern and interviews) facilitated interpretation. Research has shown that adults' attitudes toward the environment strongly influence children's attitudes regarding the environment. Science teachers' attitudes toward nature and attitudes toward children's field experiences influence the number and types of field trips teachers take. Measuring teacher attitudes is a way to assess teacher beliefs.

The one day outdoor field trip had significant outcomes for …

Potential Effects Of Altered Precipitation Regimes On Primary Production In Terrestrial Ecosystems, Joanna S. Hsu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In addition to causing an increase in mean temperatures, climate change is also altering precipitation regimes across the globe. General circulation models project both latitude-dependent changes in precipitation mean and increases in precipitation variability. These changes in water availability will impact terrestrial primary productivity, the fixation of carbon dioxide into organic matter by plants. In my thesis, I addressed the following three questions: 1.) What will be the relative effect of changes in the mean and standard deviation of annual precipitation on mean annual primary production? 2.) Which ecosystems will be the most sensitive to changes in precipitation? 3.) Will …

Magnetic Susceptibility As A Proxy For Investigating Microbially Mediated Iron Reduction, Farag M. Mewafy, Estella A. Atekwana, D. Dale Werkema, Lee D. Slater, Dimitrios Ntarlagiannis, Andre Revil, Magnus E. Skold, Geoffrey N. Delin

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

We investigated magnetic susceptibility (MS) variations in hydrocarbon contaminated sediments. Our objective was to determine if MS can be used as an intrinsic bioremediation indicator due to the activity of iron-reducing bacteria. A contaminated and an uncontaminated core were retrieved from a site contaminated with crude oil near Bemidji, Minnesota and subsampled for MS measurements. The contaminated core revealed enriched MS zones within the hydrocarbon smear zone, which is related to iron-reduction coupled to oxidation of hydrocarbon compounds and the vadose zone, which is coincident with a zone of methane depletion suggesting aerobic or anaerobic oxidation of methane is coupled …

Agglutinated Foraminifera From The Northern Tarcău Nappe (Eastern Carpathians, Romania), Raluca Bindiu, Sorin Filipescu

Studia UBB Geologia

The Tarcău Nappe is the most important unit of the Carpathian flysch due to its size, stratigraphic, and tectonic complexity. Our purpose was to identify the major types of foraminifera assemblages in relation to the paleoenvironmental settings and their biostratigraphic potential. The identified assemblages are characteristic to the Cretaceous and Paleogene, consisting mostly of benthic agglutinated and, in lower proportions, benthic calcareous and planktonic species. Local abundances of Glomospira specimens allowed the correlation of the examined strata to the early Eocene “Glomospira event” described from the Carpathians in Poland, Morocco, and Labrador. Rzehakina fissistomata (Grzybowski) identified at Palma makes …

Tracking Large Carnivore Dispersal Using Isotopic Clues In Claws: An Application To Cougars Across The Great Plains, Viviane Hénaux, Larkin A. Powell, Keith A. Hobson, Clayton Kent Nielsen, Michelle A. Larue

School of Natural Resources: Faculty Publications

1. Cougar (Puma concolor) populations, like other large carnivores, have increased during recent decades and may be recolonizing their former ranges in Midwestern North America. The dispersal routes taken by these animals from established populations are unknown and insight into these movements would facilitate their conservation and management.

2. We inferred the origin and migration route of four dispersing cougars using stable hydrogen (δD) and carbon (δ¹³C) isotope values along one of their claws. We compared isotopic variations within claws to regional and large-scale isoscapes of δD and δ¹³C values in prey species. Using …

Extreme Variation In The Sagittal Crest Of Tapirus Polkensis (Mammalia Perissodactyla) At The Gray Fossil Site Northeastern Tn., Aaron Randall Abernethy

Electronic Theses and Dissertations

The preservation and quantity of fossil tapirs (Tapirus polkensis) from the Gray Fossil Site in northeastern Tennessee provides a unique opportunity for comparison and analysis of skeletal characters. Intraspecifically, modern tapirs show little to no variation in the morphology of the sagittal crest. However, several different morphologies exist within the sample at Gray. No osteological evidence of sexual dimorphism exists for tapirs, and no correlation between crest shape and sex was observed. Several juveniles display well defined crests, while some adults have only minor thickening of the temporal ridges; therefore, no distinct correlation between age and crest state …