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Four-Toed Salamander (Hemidactylium Scutatum) Nest Site Characteristics In Natural And Constructed Wetlands In Eastern Kentucky, Susan Kay King Jan 2012

Four-Toed Salamander (Hemidactylium Scutatum) Nest Site Characteristics In Natural And Constructed Wetlands In Eastern Kentucky, Susan Kay King

Online Theses and Dissertations

Forested freshwater wetlands have undergone loss and alteration more than other types of wetlands. Wetland creation has slowed wetland losses, but many created wetlands do not functionally replace natural wetlands. Plant and animal communities and wetland drying cycles often differ between natural and constructed wetlands. It is important to understand what specific habitat characteristics differ between natural and constructed wetlands and what impact these differences might have on the animal assemblages. Having restrictive habitat requirements makes the four-toed salamander a good candidate for study. The objectives of this study were to understand four-toed salamander (Hemidactylium scutatum) nesting ecology …


Oil-Mediated Mortality And Induced Behavioral Modifications Of Coastal Insects, Benjamin Jacob Adams Jan 2012

Oil-Mediated Mortality And Induced Behavioral Modifications Of Coastal Insects, Benjamin Jacob Adams

LSU Master's Theses

The Deepwater Horizon oil spill affected over one thousand kilometers of the southeastern United States’ coast in the Gulf of Mexico especially Louisiana’s salt marshes. These marshes are a vital part of the state’s economy and coastal ecology; however, the insects residing in this area remain largely unstudied. The goal of my project was to answer specific questions arising from two ongoing investigations of the insects in the oiled marshes. I sampled insects using sweep nets and insect vacuums to determine the most efficient technique to use in the marsh, compared insects collected in oiled and non-oiled marshes, and completed …


The Role Of Plant-Soil Feedback In Exotic Plant Invasion: Soil Type, Biotic Or Abiotic Factors?, Kelly Dawn Schradin Jan 2012

The Role Of Plant-Soil Feedback In Exotic Plant Invasion: Soil Type, Biotic Or Abiotic Factors?, Kelly Dawn Schradin

Browse all Theses and Dissertations

Plants alter soil characteristics in many ways causing changes in their subsequent growth resulting in either positive or negative feedback on their own fitness. Plants in their native ranges typically experience negative feedback from natural enemies, while feedback is often positive in invaded ranges where they escape enemies, experience new beneficial mutualisms, or bring with them a novel biochemical weapon. I conducted a fully factorial greenhouse experiment to examine plant-soil feedback in the invasive shrub Lonicera maackii and whether or not positive feedback may contribute to its successful invasion in southern Ohio. I also investigated whether the sign and strength …


Widespread Triploidy In Western North American Aspen (Populus Tremuloides), Karen E. Mock, Colin M. Callahan, M. Nurul Islam-Faridi, John D. Shaw, Hardeep S. Rai, Stewart C. Sanderson, Carol A. Rowe, Ronald J. Rye, Michael D. Madritch, Richard S. Gardner, Paul G. Wolf Jan 2012

Widespread Triploidy In Western North American Aspen (Populus Tremuloides), Karen E. Mock, Colin M. Callahan, M. Nurul Islam-Faridi, John D. Shaw, Hardeep S. Rai, Stewart C. Sanderson, Carol A. Rowe, Ronald J. Rye, Michael D. Madritch, Richard S. Gardner, Paul G. Wolf

Biology Faculty Publications

We document high rates of triploidy in aspen (Populus tremuloides) across the western USA (up to 69% of genets), and ask whether the incidence of triploidy across the species range corresponds with latitude, glacial history (as has been documented in other species), climate, or regional variance in clone size. Using a combination of microsatellite genotyping, flow cytometry, and cytology, we demonstrate that triploidy is highest in unglaciated, drought-prone regions of North America, where the largest clone sizes have been reported for this species. While we cannot completely rule out a low incidence of undetected aneuploidy, tetraploidy or duplicated loci, our …


Nepetalactones From Essential Oil Of Nepeta Cataria Represent A Stable Fly Feeding And Oviposition Repellent, J. J. Zhu, Dennis R. Berkebile, C. E. Dunlap, A. Zhang, D. Boxler, K. Tangtrakulwanich, R. Behle, Frederick P. Baxendale, Gary J. Brewer Jan 2012

Nepetalactones From Essential Oil Of Nepeta Cataria Represent A Stable Fly Feeding And Oviposition Repellent, J. J. Zhu, Dennis R. Berkebile, C. E. Dunlap, A. Zhang, D. Boxler, K. Tangtrakulwanich, R. Behle, Frederick P. Baxendale, Gary J. Brewer

Department of Entomology: Faculty Publications

The stable fly, Stomoxys calcitrans (L.) (Diptera: Muscidae), is one of the most serious pests to livestock. It feeds mainly on cattle and causes significant economic losses in the cattle industry. Standard stable fly control involving insecticides and sanitation is usually costly and often has limited effectiveness. As we continue to evaluate and develop safer fly control strategies, the present study reports on the effectiveness of catnip (Nepeta cataria L.) oil and its constituent compounds, nepetalactones, as stable fly repellents. The essential oil of catnip reduced the feeding of stable flies by >96% in an in vitro bioassay system, …


Clinical Use Of Probiotics In Pediatric Allergy (Cuppa): A World Allergy Organization Position Paper, Alessandro Fiocchi, Wesley Burks, Sami L. Bahna, Leonard Bielory, Robert J. Boyle, Renata Cocco, Sten Dreborg, Richard E. Goodman, Mikael Kuitunen, Tari Haahtela, Ralf G. Heine, Gideon Lack, David A. Osborn, Hugh Sampson, Gerald W. Tannock, Bee Wah Lee Jan 2012

Clinical Use Of Probiotics In Pediatric Allergy (Cuppa): A World Allergy Organization Position Paper, Alessandro Fiocchi, Wesley Burks, Sami L. Bahna, Leonard Bielory, Robert J. Boyle, Renata Cocco, Sten Dreborg, Richard E. Goodman, Mikael Kuitunen, Tari Haahtela, Ralf G. Heine, Gideon Lack, David A. Osborn, Hugh Sampson, Gerald W. Tannock, Bee Wah Lee

Department of Food Science and Technology: Faculty Publications

Background: Probiotic administration has been proposed for the prevention and treatment of specific allergic manifestations such as eczema, rhinitis, gastrointestinal allergy, food allergy, and asthma. However, published statements and scientific opinions disagree about the clinical usefulness.

Objective: A World Allergy Organization Special Committee on Food Allergy and Nutrition review of the evidence regarding the use of probiotics for the prevention and treatment of allergy.

Methods: A qualitative and narrative review of the literature on probiotic treatment of allergic disease was carried out to address the diversity and variable quality of relevant studies. This variability precluded systematization, and an expert …


Fine-Scale Geographic Variation Of Stable Isotope And Fatty Acid Signatures Of Three Fish Species In The Indian River Lagoon, Fl, Jennifer Fletcher Odom Jan 2012

Fine-Scale Geographic Variation Of Stable Isotope And Fatty Acid Signatures Of Three Fish Species In The Indian River Lagoon, Fl, Jennifer Fletcher Odom

Electronic Theses and Dissertations

The Indian River Lagoon, Florida, is a unique closed “bar built” estuary system that has little interchange with the Atlantic Ocean and which is home to many resident species. Three fish species were investigated to see if their isotopic and fatty acid signatures differed based on geographic location. The goal was to assess the degree of resolution of spatial variation that is possible when using stable isotope and fatty acid signature analysis to interpret feeding habits and potential linkages between feeding habits and health status. Spotted seatrout (n=40), pinfish (n=60) and white mullet (n=60) were collected over a 4 week …


Spatial Ecology Of The Trans-Pecos Rat Snake (Bogertophis Subocularis) In The Chihuahuan Desert Of Trans-Pecos Texas, Arturo Rocha Jan 2012

Spatial Ecology Of The Trans-Pecos Rat Snake (Bogertophis Subocularis) In The Chihuahuan Desert Of Trans-Pecos Texas, Arturo Rocha

Open Access Theses & Dissertations

The Trans-Pecos Rat Snake (Bogertophis subocularis) is a medium to large rat snake that occurs from south-central New Mexico, south-central Texas, down into the north-central and northeastern states of Mexico. There is paucity in the ecology of B. subocularis to date. Some North American colubrid snakes, such as Thamnophis sirtalis, are the most represented species in thermal ecology and life history studies in all reptiles. There is nothing known on the winter ecological aspects of this species, and very little information regarding its overall ecology. The goal of this study is to determine home range, movement patterns, habitats and utilization …


An Assessment Of Land Cover Change At The Indio Mountains Research Station, Rebecca Anne Escamilla Jan 2012

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 …


Differential Responses Of Eastern Red-Backed Salamanders (Plethodon Cinereus) To Conspecifics And Centipedes, A. A. Burgett, Geoffrey R. Smith Jan 2012

Differential Responses Of Eastern Red-Backed Salamanders (Plethodon Cinereus) To Conspecifics And Centipedes, A. A. Burgett, Geoffrey R. Smith

Faculty Publications

No abstract provided.


Management In A Neotropical Show Cave: Planning For Invertebrates Conservation, Thais Giovannini Pellegrini, Rodrigo Lopes Ferreira Jan 2012

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 128th feast, to evaluate the effects of visitation on …


Discrimination, Crypticity, And Incipient Taxa In Entamoeba, Avelina Espinosa, Guillermo Paz-Y-Miño-C Jan 2012

Discrimination, Crypticity, And Incipient Taxa In Entamoeba, Avelina Espinosa, Guillermo Paz-Y-Miño-C

Arts & Sciences Faculty Publications

Persistent difficulties in resolving clear lineages in diverging populations of prokaryotes or unicellular eukaryotes (protistan polyphyletic groups) are challenging the classical species concept. Although multiple integrated approaches would render holistic taxonomies, most phylogenetic studies are still based on single-gene or morphological traits. Such methodologies conceal natural lineages, which are considered “cryptic.” The concept of species is considered artificial and inadequate to define natural populations. Social organisms display differential behaviors toward kin than to nonrelated individuals. In “social” microbes, kin discrimination has been used to help resolve crypticity. Aggregative behavior could be explored in a nonsocial protist to define phylogenetic varieties …


A Preliminary Study On The Length-Weight Relationship Of Sacura Boulengeri (Heemstra, 1973) From Indian Waters, Kinattumkara Bineesh, Sebastine Manju, Kallivalappil Akhilesh, Gopalakrishna Pillai Jan 2012

A Preliminary Study On The Length-Weight Relationship Of Sacura Boulengeri (Heemstra, 1973) From Indian Waters, Kinattumkara Bineesh, Sebastine Manju, Kallivalappil Akhilesh, Gopalakrishna Pillai

Turkish Journal of Zoology

Sacura boulengeri (Heemstra, 1973) is a rare serranid fish (Subfamily: Anthiinae) having very disjunct distribution in the western Indian Ocean. The rarity of the species is evident from earlier reports and, so far, no related studies on the species have been published except on taxonomy and distributional records. In the present investigation, the length-weight relationship of Sacura boulengeri was estimated to be W = 0.0777 × L2.690 (with 95% confidence intervals for b and r2). An analysis of the stomach contents revealed that sergestid shrimps and copepods were the major food items of the diet.


Spatial And Temporal Variations In The Species Composition And Abundance Of Benthic Molluscs Along 4 Rocky Shores Of Karachi, Solaha Rahman, Sohail Barkati Jan 2012

Spatial And Temporal Variations In The Species Composition And Abundance Of Benthic Molluscs Along 4 Rocky Shores Of Karachi, Solaha Rahman, Sohail Barkati

Turkish Journal of Zoology

A total of 97 species of macromolluscs were collected from 4 rocky beaches (Manora, Buleji, Nathiagali, and Cape Monze) along the Karachi coast from December 1993 to December 1995. More species were recorded from Buleji (68) and Manora (63) than from Nathiagali (55) and Cape Monze (57). Gastropods dominated at all 4 of the sites studied. Four species were commonly abundant at all 4 sites: Turbo coronatus, Nerita albicilla, Morula granulata, and Cerithium rubus. The average number of species decreased with an increase in the tidal heights at Manora, Buleji, and Nathiagali, whereas this was greater in the high tidal …


The Land Snail Fauna Of Mut District (Mersin Province, Turkey), Ümi̇t Kebapçi, Mehmet Zeki̇ Yildirim, İskender Gülle, Mustafa Öztop, Duygu Ceren Çağlan Jan 2012

The Land Snail Fauna Of Mut District (Mersin Province, Turkey), Ümi̇t Kebapçi, Mehmet Zeki̇ Yildirim, İskender Gülle, Mustafa Öztop, Duygu Ceren Çağlan

Turkish Journal of Zoology

The land snail fauna of the Mut District was surveyed during the spring (April-May) of 2008. A total of 31 species and subspecies-9 (29%) of them endemics-belonging to 26 genera and 14 families were determined from 41 localities. Dominant families were Enidae, Orculidae, and Hygromiidae. Humidity, vegetation, and habitat type were the determinants of species richness in the study area. Species composition, according to cluster and multivariate analyses, was also found to be affected by the altitude factor.


Δ13c Is A Signature Of Light Availability And Photosynthesis In Seagrass, Xingping Hu, David J. Burdige, Richard C. Zimmerman Jan 2012

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 …


Effects Of Grassland Alteration From Mowing And Fire On Bird Activity At A Colorado Airfield, Kara A. Carragher, Rick M. Clawges, Rick L. Bunn, Helen K. Pigage, Jon C. Pigage Jan 2012

Effects Of Grassland Alteration From Mowing And Fire On Bird Activity At A Colorado Airfield, Kara A. Carragher, Rick M. Clawges, Rick L. Bunn, Helen K. Pigage, Jon C. Pigage

Human–Wildlife Interactions

Grass management has been used for many years at airports in an attempt to reduce numbers of birds and other wildlife and the collisions with aircraft associated with them. We evaluated the impacts of grassland alteration by mowing and fi re on the abundance, diversity, and frequency of birds using 1 control and 2 experimental grass plots from 2009 to 2010 on a U.S. Army airfield in Colorado located in short-grass prairie. Density of breeding birds was highest in the mowed plot. Numbers of birds observed in 34 surveys conducted during the non-breeding season in the burned (x = 41) …


A Qcm-Adhering Bacillus Anthracis Soil Phage Assemblage Is Less Diverse Than A Total B. Anthracis Soil Phage Assemblage, Gabriel David Connell Jan 2012

A Qcm-Adhering Bacillus Anthracis Soil Phage Assemblage Is Less Diverse Than A Total B. Anthracis Soil Phage Assemblage, Gabriel David Connell

Dissertations and Theses @ UNI

Recently, phages have been used as affinity reagents in quartz crystal microbalance (QCM)-based biodetection methods. The goal of this study was to isolate and characterize a Bacillus cereus group soil-phage assemblage, which was isolated from 5 grams of local topsoil, and compare its population structure to that of a similar phage assemblage that had been additionally selected by adhering to a QCM electrode. Viruses aren't well-defined in terms of 'species', therefore operational taxonomic units (OTUs) were defined by structural protein profiles from sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). We were able to obtain a conservative estimate of soilphage 'species' richness …


Coyote (Canis Latrans), 100+ Years In The East: A Literature Review, Lauren L. Mastro, Eric M. Gese, Julie K. Young, John A. Shivik Jan 2012

Coyote (Canis Latrans), 100+ Years In The East: A Literature Review, Lauren L. Mastro, Eric M. Gese, Julie K. Young, John A. Shivik

United States Department of Agriculture Wildlife Services: Staff Publications

Coyotes (Canis latrans) have expanded into the eastern United States over the last 100 years. Increases in their distribution and abundance have been documented and concerns about their presence in urban areas and their impact on both native wildlife and domestic livestock are growing. These impacts require further investigation and may require changes to management strategies. Two documents, a book and a technical bulletin, provide general overviews of eastern coyote biology. However, these documents are not comprehensive, and are either not readily available or were published >15 years ago. We provide a comprehensive review of the existing literature …


Genetic Measures Confirm Familial Relationships And Strengthen Study Design, Stacie J. Robinson, Ryan D. Walrath, Timonthy R. Vandeelen, Kurt C. Vercauteren Jan 2012

Genetic Measures Confirm Familial Relationships And Strengthen Study Design, Stacie J. Robinson, Ryan D. Walrath, Timonthy R. Vandeelen, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

Social structure and behavioral interactions between individuals shape basic biological processes, such as breeding; foraging and predator avoidance; movement and dispersal; and disease transmission. We used a targeted trapping strategy to capture kin groups of white-tailed deer (Odocoileus virginianus) during 2007 and 2008 in Sandhill Wildlife Research Area, Wisconsin, USA, in order to observe social behaviors. Because inferring family relationships from observation of behavior is subjective, we usedmeasures of genetic relatedness and parentage assignment tests to determine that our capture strategy was efficient for capturing related pairs (78% of groups contained 1 dyad of related animals). The results of …


Efficacy Of Proximity Loggers For Detection Of Contacts Between Maternal Pairs Of White-Tailed Deer, Ryan Walrath, Timonthy R. Vandeelen, Kurt C. Vercauteren Jan 2012

Efficacy Of Proximity Loggers For Detection Of Contacts Between Maternal Pairs Of White-Tailed Deer, Ryan Walrath, Timonthy R. Vandeelen, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

Contact frequency and duration estimates between individuals are important to understanding the behavioral ecology of wildlife species and the epidemiology of infectious diseases. A new technology uses proximity data loggers to record time and duration of contacts. We conducted an experiment at Sandhill Wildlife Management Area, located near Babcock, Wisconsin (USA) to compare probabilities of detecting intraspecific contacts among white-tailed deer (Odocoileus virginianus) maternal pairs (dams/fawns) based on detections from proximity loggers deployed on collars versus those obtained from direct observation. We defined 5 discrete probabilities of detection of a contact in terms of P (probability of detection …


The Impact Of Solar Radiation On The Distribution Of The Red Imported Fire Ant, Solenopsis Invicta (Hymenoptera: Formicidae), Audrey Marie Hernando Jan 2012

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 …


The Impact Of Decadal Land Cover Change On The Global Warming Potential Of Beringian Arctic Tundra, David Hwei-Len Lin Jan 2012

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 …


Stable Isotope Diet Reconstruction Of Feral Horses (Equus Caballas) On The Sheldon National Wildlife Refuge, Nevada, Usa, Megan Kathleen Nordquist Dec 2011

Stable Isotope Diet Reconstruction Of Feral Horses (Equus Caballas) On The Sheldon National Wildlife Refuge, Nevada, Usa, Megan Kathleen Nordquist

Theses and Dissertations

Feral horse management has become a subject of significant controversy in the United States. This is because of differing opinions and minimal recent empirical data on feral horses. In recent years, numbers of feral horses have increased due to governmental horse removal restrictions (specifically the Wild Horse and Burro act of 1971). With increasing numbers of feral horses on rangelands, land managers are challenged with identifying the appropriate course of action for satisfying groups with differing opinions. The purpose of this study is to characterize diet consumption through the use of stable isotope dietary analysis (δ15N and δ13C). We did …


A Comparison Of Presettlement And Modern Forest Composition Along An Elevation Gradient In Central New Hampshire, Matthew A. Vadeboncoeur, Steven P. Hamburg, Charles V. Cogbill, Wendy Y. Sugimura Dec 2011

A Comparison Of Presettlement And Modern Forest Composition Along An Elevation Gradient In Central New Hampshire, Matthew A. Vadeboncoeur, Steven P. Hamburg, Charles V. Cogbill, Wendy Y. Sugimura

All Materials

Tree species composition is influenced not only by edaphic and climatic factors but also by natural and human-caused disturbances. To understand interactions among these influences, we compared forest species composition data from the time of European settlement with modern data. We derived elevation data for 2529 trees mapped by early land surveys (1770–1850) across a 1000 m elevation gradient in central New Hampshire and compared these with modern data (2004–2009) from the Forest Inventory and Analysis program (123 plots containing 2126 trees) and from permanent plots representing case studies of different land-use histories. Spruce and beech are much less abundant …


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 Dec 2011

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 …


Composition And Ecophysiological Proficiency Of Tidal Freshwater Forested Wetlands: Investigating Basin, Landscape, And Microtopographic Scales, Jamie Duberstein Dec 2011

Composition And Ecophysiological Proficiency Of Tidal Freshwater Forested Wetlands: Investigating Basin, Landscape, And Microtopographic Scales, Jamie Duberstein

All Dissertations

A hierarchical approach to forest community assessment was conducted by first focusing on landscape associations to edaphic factors among major tidal freshwater forested wetland basins in the Southeast. Four general tree communities exist along coastal rivers in the southeastern United States, based on the most prominent species in each: Water Tupelo, Swamp Tupelo, Dwarf Palmetto, and Cabbage Palm. Microhabitat usage and preference by trees were then examined, both across all species and within species, as related to such factors as coast, presence on rivers with dams, tree community assemblage, relative distance from the river, specific river basin, and microsite availability. …


Effects Of Canopy And Cultural Treatments On Fine Fuel Production, Fire Behavior, And Short-Term Fire Effects In Loblolly Pine (>I/I< L.) Stands Being Restored To Longleaf Pine (>I/I< Mill.), Carsyn Tennant Dec 2011

Effects Of Canopy And Cultural Treatments On Fine Fuel Production, Fire Behavior, And Short-Term Fire Effects In Loblolly Pine (>I/I< L.) Stands Being Restored To Longleaf Pine (>I/I< Mill.), Carsyn Tennant

All Theses

Across the southeastern United States, anthropogenic factors such as land conversion and fire suppression have resulted in the prevalence of loblolly pine in areas historically occupied by longleaf pine. Compared to longleaf pine forests, loblolly stands often contain a substantial broad-leaved midstory and lack the ground layer that contributes fuels essential for the frequent, low intensity surface fire regime necessary to sustain the longleaf ecosystem. Currently, there is considerable interest in restoring longleaf pine habitats to areas occupied by loblolly pine. The retention of mature canopy trees is often necessary to maintain ecosystem function, to preserve habitat features, and to …


Bryoecology In The American Southwest: Patterns Of Biodiversity And Responses To Global Change, John Carroll Brinda Dec 2011

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 …


Msh1 Influence On Plant Mitochondrial Genome Recombination And Phenotype In Tobacco, Peibei Sun Dec 2011

Msh1 Influence On Plant Mitochondrial Genome Recombination And Phenotype In Tobacco, Peibei Sun

School of Biological Sciences: Dissertations, Theses, and Student Research

Plant mitochondrial genomes are composed of unusually complex structures, due to active recombination at numerous repeated sequences in the genome. The maintenance of mitochondrial genome stability is under the control of identifiable nuclear genes. In plants, three nuclear genes (MSH1, RECA3 and OSB1) have been shown to participate in recombination surveillance and the suppression of illegitimate recombination in mitochondria. Disruption of these loci in Arabidopsis results in reproducible mitochondrial genome rearrangements. We demonstrated that repeat-mediated de novo recombination was also enhanced in both Arabidopsis and tobacco during passage through in vitro culture. Furthermore, in vitro conditions led …