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Integrating Habitat Suitability Modeling And Radio Telemetry To Describe Habitat Use Of The Western Massasaugas, Sistrurus T. Tergeminus, In Texas, Mitchell R. Barazowski Dec 2016

Integrating Habitat Suitability Modeling And Radio Telemetry To Describe Habitat Use Of The Western Massasaugas, Sistrurus T. Tergeminus, In Texas, Mitchell R. Barazowski

Biology Theses

Habitat suitability modeling using the software package MaxEnt (Phillips, Anderson, & Schapire, 2006) is a popular method for describing the habitat of rare species. MaxEnt uses “presence only” data to develop models; however presence data are highly skewed towards areas of high detection probability and these areas may not represent the full range of habitat use. Thusly, predictions from models developed using only data from areas with high detection probability may not represent all suitable habitat. This study tested the ability of MaxEnt models developed using three different data sets to accurately describe Western Massasauga (Sistrurus t. tergeminus) habitat at …


Territoriality And Spatial Structure In The Green Anole, Anolis Carolinensis, William D. Weber Jr. Dec 2016

Territoriality And Spatial Structure In The Green Anole, Anolis Carolinensis, William D. Weber Jr.

LSU New Orleans Theses and Dissertations

Anolis carolinensis has been a model organism for ecology and evolutionary biology since the seventies, yet there are still understudied aspects of their ecology. A five-year study has provided microsatellite genotypes to be used in building a pedigree and assess relatedness, enabling us to evaluate the spatial distribution of an urban population of A. carolinensis. Results indicate no correlation between a male’s size and the distance others keep from it; however, males belonging in the heavyweight morph are dictating the spatial distribution in this population. In addition, juvenile dispersal of male offspring and partial philopatry of female offspring are …


Phylogenetics, Biogeography, And Climate Niche Variation Of South Pacific And Hawaiian Psychotria, Elaine Zhang Dec 2016

Phylogenetics, Biogeography, And Climate Niche Variation Of South Pacific And Hawaiian Psychotria, Elaine Zhang

Master's Theses

Why do some species have broad geographic distributions, while other species are confined to a narrow distribution? Species age, ecological niche, or dispersal traits may help explain why some insular species are abundant and found on many islands, while others are rare and restricted to one island. In this study, I inferred a robust, time-calibrated phylogeny of the Hawaiian Psychotria, using two nuclear and eight chloroplast loci, sampling 67 individuals. I coupled my phylogenetic hypothesis with climatic data, ecological niche modeling, and morphological dispersal characteristics to explain the variation in number of islands occupied by each species. My inferred phylogeny …


Circadian And Circatidal Rhythms Of Protein Abundance In The Intertidal Mussel Mytilus Californianus, Cory Elowe Dec 2016

Circadian And Circatidal Rhythms Of Protein Abundance In The Intertidal Mussel Mytilus Californianus, Cory Elowe

Master's Theses

The intertidal zone is a dynamic environment that fluctuates with the 12.4-h tidal and 24-h light/dark cycle to predictably alter food availability, temperature, air exposure, wave action, oxygen partial pressure, and osmotic conditions. Intertidal sessile bivalves exhibit behavioral or physiological changes to minimize the persistent challenges of fluctuating environmental conditions, such as adjusting gaping behavior and heart rate. At the cellular level, transcriptomic studies on mussels’ baseline circadian and circatidal rhythms have determined that the circadian rhythm is the dominant transcriptional rhythm. However, as proteins reflect the basic molecular phenotype of an organism and their abundance may differ greatly from …


Marine Ecoregion And Deepwater Horizon Oil Spill Affect Recruitment And Population Structure Of A Salt Marsh Snail, Steven C. Pennings, Scott Zengel, Jacob Oehrig, Merryl Alber, T. Dale Bishop, Donald R. Deis, Donna Devlin, A. Randall Hughes, John J. Hutchens, Whitney M. Kiehn, Caroline R. Mcfarlin, Clay L. Montague, Sean Powers, C. Edward Proffitt, Nicolle Rutherford, Camille L. Stagg, Keith Walters Dec 2016

Marine Ecoregion And Deepwater Horizon Oil Spill Affect Recruitment And Population Structure Of A Salt Marsh Snail, Steven C. Pennings, Scott Zengel, Jacob Oehrig, Merryl Alber, T. Dale Bishop, Donald R. Deis, Donna Devlin, A. Randall Hughes, John J. Hutchens, Whitney M. Kiehn, Caroline R. Mcfarlin, Clay L. Montague, Sean Powers, C. Edward Proffitt, Nicolle Rutherford, Camille L. Stagg, Keith Walters

Biology

Marine species with planktonic larvae often have high spatial and temporal variation in recruitment that leads to subsequent variation in the ecology of benthic adults. Using a combination of published and unpublished data, we compared the population structure of the salt marsh snail, Littoraria irrorata, between the South Atlantic Bight and the Gulf Coast of the United States to infer geographic differences in recruitment and to test the hypothesis that the Deepwater Horizon oil spill led to widespread recruitment failure of L. irrorata in Louisiana in 2010. Size-frequency distributions in both ecoregions were bimodal, with troughs in the distributions consistent …


The Biodiversity Of Gastrointestinal Nematodes In South African Wildlife, Chalis J. Bird Dec 2016

The Biodiversity Of Gastrointestinal Nematodes In South African Wildlife, Chalis J. Bird

Theses, Dissertations, and Projects

In this study, I investigated the diversity of parasites found in cheetah and wild ungulates in South Africa in collaboration with the Samara Private Game Reserve in Graaff Reinet, South Africa. Scat samples were collected over a period of two months, from September November, 2014, and DNA was extracted on the preserve for gastrointestinal nematode analysis. Wildlife was tracked using radio telemetry, tracks, and sign, while habitat and host distribution were documented. The aim was to determine the community composition of gastrointestinal nematodes in the wildlife hosts through molecular identification and to examine the role of host habitat preference, geographical …


Wolf Predation: Where And How Wolves Kill Beavers, And Confronting The Biases In Scat-Based Diet Studies, Thomas Gable Dec 2016

Wolf Predation: Where And How Wolves Kill Beavers, And Confronting The Biases In Scat-Based Diet Studies, Thomas Gable

All NMU Master's Theses

Beavers can be a significant prey item for wolves in boreal systems but how wolves hunt beavers is largely unknown. I inferred how wolves hunt beavers by identifying 22 kill sites using clusters of locations from GPS-collared wolves in Voyageurs National Park, Minnesota. Where wolves killed beavers varied seasonally with the majority (58%) of kills in the spring occurring below dams and on shorelines while the majority (80%) of kills in the fall were near feeding trails and canals. I deduced that the typical hunting strategy has 3 components: 1) waiting near areas of high beaver use until a beaver …


Where And How Wolves (Canis Lupus) Kill Beavers (Castor Canadensis), Thomas Gable, Steve K. Windels, John G. Bruggink, Austin T. Homkes Dec 2016

Where And How Wolves (Canis Lupus) Kill Beavers (Castor Canadensis), Thomas Gable, Steve K. Windels, John G. Bruggink, Austin T. Homkes

Journal Articles

Beavers (Castor canadensis) can be a significant prey item for wolves (Canis lupus) in boreal ecosystems due to their abundance and vulnerability on land. How wolves hunt beavers in these systems is largely unknown, however, because observing predation is challenging. We inferred how wolves hunt beavers by identifying kill sites using clusters of locations from GPS-collared wolves in Voyageurs National Park, Minnesota. We identified 22 sites where wolves from 4 different packs killed beavers. We classified these kill sites into 8 categories based on the beaver-habitat type near which each kill occurred. Seasonal variation existed in …


Effect Of Fragmentation And Habitat Type On Coastal Nekton In Mississippi, Thomas Bennett Sevick Dec 2016

Effect Of Fragmentation And Habitat Type On Coastal Nekton In Mississippi, Thomas Bennett Sevick

Master's Theses

Coastal wetlands are extremely productive ecosystems that support an abundance of organisms at higher tropic levels. Coastal wetlands also act as important buffers from storms and help protect major cornerstones of coastal economies, such as tourism and fisheries. Despite the clear need for the protection of these habitats, anthropogenic use of coastal wetlands has increased in frequency and intensity, resulting in the fragmentation of once continuous habitats. A central challenge to assessing the impact of marsh fragmentation is the lack of quantitative distribution and abundance data from specific habitat types. This is especially true for species that are not commercially …


Contribution Of Lianas To Plant Area Index And Canopy Structure In A Panamanian Forest, M. Elizabeth Rodríguez-Ronderos, Gil Bohrer, Arturo Sanchez-Azofeifa, Jennifer S. Powers, Stefan A. Schnitzer Dec 2016

Contribution Of Lianas To Plant Area Index And Canopy Structure In A Panamanian Forest, M. Elizabeth Rodríguez-Ronderos, Gil Bohrer, Arturo Sanchez-Azofeifa, Jennifer S. Powers, Stefan A. Schnitzer

Biological Sciences Faculty Research and Publications

Lianas are an important component of tropical forests, where they reduce tree growth, fecundity, and survival. Competition for light from lianas may be intense; however, the amount of light that lianas intercept is poorly understood. We used a large-scale liana-removal experiment to quantify light interception by lianas in a Panamanian secondary forest. We measured the change in plant area index (PAI) and forest structure before and after cutting lianas (for 4 yr) in eight 80 m × 80 m plots and eight control plots (16 plots total). We used ground-based LiDAR to measure the 3-dimensional canopy structure before cutting lianas, …


Integration Of Plant Defense Traits With Biological Control Of Arthropod Pests: Challenges And Opportunities, Julie A. Peterson, Paul J. Ode, Camila Oliveira-Hofman, James D. Harwood Nov 2016

Integration Of Plant Defense Traits With Biological Control Of Arthropod Pests: Challenges And Opportunities, Julie A. Peterson, Paul J. Ode, Camila Oliveira-Hofman, James D. Harwood

Entomology Faculty Publications

Crop plants exhibit a wide diversity of defensive traits and strategies to protect themselves from damage by herbivorous pests and disease. These defensive traits may be naturally occurring or artificially selected through crop breeding, including introduction via genetic engineering. While these traits can have obvious and direct impacts on herbivorous pests, many have profound effects on higher trophic levels, including the natural enemies of herbivores. Multi-trophic effects of host plant resistance have the potential to influence, both positively and negatively, biological control. Plant defense traits can influence both the numerical and functional responses of natural enemies; these interactions can be …


Integration Of Plant Defense Traits With Biological Control Of Arthropod Pests: Challenges And Opportunities, Julie A. Peterson, Paul J. Ode, Camila Oliveira-Hofman, James D. Harwood Nov 2016

Integration Of Plant Defense Traits With Biological Control Of Arthropod Pests: Challenges And Opportunities, Julie A. Peterson, Paul J. Ode, Camila Oliveira-Hofman, James D. Harwood

Department of Entomology: Faculty Publications

Crop plants exhibit a wide diversity of defensive traits and strategies to protect themselves from damage by herbivorous pests and disease. These defensive traits may be naturally occurring or artificially selected through crop breeding, including introduction via genetic engineering. While these traits can have obvious and direct impacts on herbivorous pests, many have profound effects on higher trophic levels, including the natural enemies of herbivores. Multi-trophic effects of host plant resistance have the potential to influence, both positively and negatively, biological control. Plant defense traits can influence both the numerical and functional responses of natural enemies; these interactions can be …


Problems Of Multi-Species Organisms: Endosymbionts To Holobionts, David C. Queller, Joan E. Strassmann Nov 2016

Problems Of Multi-Species Organisms: Endosymbionts To Holobionts, David C. Queller, Joan E. Strassmann

Biology Faculty Research

The organism is one of the fundamental concepts of biology and has been at the center of many discussions about biological individuality, yet what exactly it is can be confusing. The definition that we find generally useful is that an organism is a unit in which all the subunits have evolved to be highly cooperative, with very little conflict. We focus on how often organisms evolve from two or more formerly independent organisms. Two canonical transitions of this type—replicators clustered in cells and endosymbiotic organelles within host cells—demonstrate the reality of this kind of evolutionary transition and suggest conditions that …


Different Prey Resources Suggest Little Competition Between Non-Native Frogs And Insectivorous Birds Despite Isotopic Niche Overlap, Robyn L. Smith, Karen H. Beard, Aaron B. Shiels Nov 2016

Different Prey Resources Suggest Little Competition Between Non-Native Frogs And Insectivorous Birds Despite Isotopic Niche Overlap, Robyn L. Smith, Karen H. Beard, Aaron B. Shiels

Wildland Resources Faculty Publications

Non-native amphibians often compete with native amphibians in their introduced range, but their competitive effects on other vertebrates are less well known. The Puerto Rican coqui frog (Eleutherodactylus coqui) has colonized the island of Hawaii, and has been hypothesized to compete with insectivorous birds and bats. To address if the coqui could compete with these vertebrates, we used stable isotope analyses to compare the trophic position and isotopic niche overlap between the coqui, three insectivorous bird species, and the Hawaiian hoary bat. Coquis shared similar trophic position to Hawaii amakihi, Japanese white-eye, and red-billed leiothrix. Coquis were about 3 ‰ …


Sandhill Crane Roost Selection, Human Disturbance, And Forage Resources, Aaron T. Pearse, Gary L. Krapu, David A. Brandt Nov 2016

Sandhill Crane Roost Selection, Human Disturbance, And Forage Resources, Aaron T. Pearse, Gary L. Krapu, David A. Brandt

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Sites used for roosting represent a key habitat requirement for many species of birds because availability and quality of roost sites can influence individual fitness. Birds select roost sites based on numerous factors, requirements, and motivations, and selection of roosts can be dynamic in time and space because of various ecological and environmental influences. For sandhill cranes (Antigone canadensis) at their main spring staging area along the Platte River in south-central Nebraska, USA, past investigations of roosting cranes focuse donphysical channel characteristics related to perceived security as motivating roost distribution.We used 6,310 roost sites selected by 313 sandhill cranes over …


Volume 2, Chapter 12-17: Terrestrial Insects: Holometabola - Diptera Biology And Habitats, Janice M. Glime Oct 2016

Volume 2, Chapter 12-17: Terrestrial Insects: Holometabola - Diptera Biology And Habitats, Janice M. Glime

Bryophyte Ecology Subchapters

No abstract provided.


The Eco-Epidemiology Of Pacific Coast Tick Fever In California, Kerry A. Padgett, Denise L. Bonilla, Marina E. Eremeeva, Carol A. Glaser, Robert S. Lane, Charsey Cole Porse, Martin B. Castro, Sharon L. Messenger, Alex Espinosa, Jill Hacker, Anne Kjemtrup, Bonnie Ryan, Jamesina J. Scott, Renjie Hu, Melissa Hardstone Yoshimizu, Gregory A. Dasch, Vicki Kramer Oct 2016

The Eco-Epidemiology Of Pacific Coast Tick Fever In California, Kerry A. Padgett, Denise L. Bonilla, Marina E. Eremeeva, Carol A. Glaser, Robert S. Lane, Charsey Cole Porse, Martin B. Castro, Sharon L. Messenger, Alex Espinosa, Jill Hacker, Anne Kjemtrup, Bonnie Ryan, Jamesina J. Scott, Renjie Hu, Melissa Hardstone Yoshimizu, Gregory A. Dasch, Vicki Kramer

Environmental Health Sciences: Faculty Publications

Rickettsia philipii (type strain “Rickettsia 364D”), the etiologic agent of Pacific Coast tick fever (PCTF), is transmitted to people by the Pacific Coast tick, Dermacentor occidentalis. Following the first confirmed human case of PCTF in 2008, 13 additional human cases have been reported in California, more than half of which were pediatric cases. The most common features of PCTF are the presence of at least one necrotic lesion known as an eschar (100%), fever (85%), and headache (79%); four case-patients required hospitalization and four had multiple eschars. Findings presented here implicate the nymphal or larval stages of D …


Intensive, Regular Sampling And Removal Of Modest Numbers Of Fishes Shows No Measurable Impact On Fish Populations In Three Streams Of North Georgia, Steven L. Powers Oct 2016

Intensive, Regular Sampling And Removal Of Modest Numbers Of Fishes Shows No Measurable Impact On Fish Populations In Three Streams Of North Georgia, Steven L. Powers

Southeastern Fishes Council Proceedings

Recent publications and restrictions on collecting by state fish and game managers indicate a growing concern regarding the impact of field sampling on native fish populations. To evaluate the validity of these concerns, data from five life-history studies conducted in Cherokee County, Georgia were examined to test the hypothesis that regular sampling has a negative impact on fish populations. Number of individuals collected was divided by time collecting to calculate catch per unit effort (CPUE) as an indicator of relative abundance for each species. The collecting sequence (i.e. the number of times a species had previously been sampled) was regressed …


Prehistoric Pathoecology As Represented By Parasites Of A Mummy From The Peruaçu Valley, Brazil, Karl Reinhard, Adauto Araújo Oct 2016

Prehistoric Pathoecology As Represented By Parasites Of A Mummy From The Peruaçu Valley, Brazil, Karl Reinhard, Adauto Araújo

Karl Reinhard Publications

Paleopathologists have begun exploring the pathoecology of parasitic diseases in relation to diet and environment. We are summarizing the parasitological findings from a mummy in the site of Lapa do Boquete, a Brazilian cave in the state of Minas Gerais. These findings in context of the archaeology of the site provided insights into the pathoecology of disease transmission in cave and rockshelter environments. We are presenting a description of the site followed by the evidence of hookworm, intestinal fluke, and Trypanosoma infection with resulting Chagas disease in the mummy discovered in the cave. These findings are used to reconstruct the …


Variability Of Lacustrine Sediment Proxy Responses To Late Holocene Climate Change As Modified By Lake Specific Processes: A Review Of Ecological And Geophysical Processes Across Northern And Eastern Iceland, Mallory Mintz Oct 2016

Variability Of Lacustrine Sediment Proxy Responses To Late Holocene Climate Change As Modified By Lake Specific Processes: A Review Of Ecological And Geophysical Processes Across Northern And Eastern Iceland, Mallory Mintz

Independent Study Project (ISP) Collection

Consistenly-deposited lake sediments provide some of the highest resolution records of local and global climates in the past, offering the potential to better understand modern climate change in the context of past climate variability. In relating proxies to their respective climate regimes, the environmental cues that the specific proxies reacted to must be isolated from the general noise of possible local influences. In this investigation, biogenic silica (BSi), total organic carbon (TOC), δ13C values, and carbon: nitrogen ratios were analyzed between lakes through northern Iceland, to review possible complicating factors specific to the use of lacustrine proxies in the interpretation …


Viral Zoonoses That Fly With Bats: A Review, Alfonso Calderon, Camilo Guzman, Jorge Salazar-Bravo, Luiz Tadeu Figueiredo, Salim Mattar, German Arrieta Sep 2016

Viral Zoonoses That Fly With Bats: A Review, Alfonso Calderon, Camilo Guzman, Jorge Salazar-Bravo, Luiz Tadeu Figueiredo, Salim Mattar, German Arrieta

MANTER: Journal of Parasite Biodiversity

Emerging infectious diseases are a growing threat to human health and a great challenge for global medical attention systems. Governmental agencies in tropical regions with abundant zoonotic pathogens should implement an active vigilance/monitoring model in bat reservoir populations because of their species richness, abundance and dispersal capabilities. Chiropterans represent approximately 20% of all mammal species, the second largest order in terms of number of species after rodents. Importantly, bats constitute natural reservoirs for potential infection of humans of several infectious disease agents such as Coronavirus, Filovirus, Lyssavirus, Paramyxovirus, and Flavivirus. Local disease outbreaks caused by new pathogens can …


Aspects Of Host Usage Of The Chestnut Lamprey (Ichthyomyzon Castaneus) In Arkansas, Jeremiah Max Salinger Sep 2016

Aspects Of Host Usage Of The Chestnut Lamprey (Ichthyomyzon Castaneus) In Arkansas, Jeremiah Max Salinger

Student Theses and Dissertations

Most native North American lamprey species are imperiled in some manner, but are curiously understudied. The research described in this thesis addresses the adult feeding biology of the Chestnut Lamprey (Ichthyomyzon castaneus), a freshwater parasitic lamprey native to the southeastern United States. This thesis addresses Chestnut Lamprey attachment site selection and size-selective parasitism of Rainbow Trout (Oncorhynchus mykiss) in an outdoor laboratory setting, as well as Chestnut Lamprey host usage and distribution in Arkansas. Approximately 75% of the 80 wounded Rainbow Trout studied were attacked in their dorsal mid-section. Chestnut Lampreys were found to select shorter hosts, with no mass …


Population Characteristics Of Human-Commensal Rodents Present In Households From Mérida, Yucatán, México, Jesús Alonso Panti-May, Silvia F. Hernández-Betancourt, Marco A. Torres-Castro, Carlos Machaín-Williams, Nohemi Cigarroa-Toledo, Lorenzo Sodá, Gabriela López-Manzanero, Josué R. Meza-Sulú, Victor M. Vidal-Martínez Sep 2016

Population Characteristics Of Human-Commensal Rodents Present In Households From Mérida, Yucatán, México, Jesús Alonso Panti-May, Silvia F. Hernández-Betancourt, Marco A. Torres-Castro, Carlos Machaín-Williams, Nohemi Cigarroa-Toledo, Lorenzo Sodá, Gabriela López-Manzanero, Josué R. Meza-Sulú, Victor M. Vidal-Martínez

MANTER: Journal of Parasite Biodiversity

Anthropocommensal rodents live in close proximity to humans in many habitats around the world. They are a threat to public health because of the pathogens they carry. Recent studies in Mérida, Yucatán, México, have shown that commensal rodents harbor potential zoonotic pathogens such as bacteria, helminths, and viruses. In this study, we describe reproductive and demographic parameters of house mice and black rats present in households from Mérida, Yucatán, México, a municipality located in a tropical region in southern México. Rodents were trapped in 142 households within the municipality of Mérida from 2011 to 2014. A total of 832 rodents …


A Global Edna Comparison Of Freshwater Bacterioplankton Assemblages Focusing On Large-River Floodplain Lakes Of Brazil, Michael Tessler, Mercer R. Brugler, Rob Desalle, Rebecca Hersch, Luiz Felipe M. Velho, Bianca T. Segovia, Fabio A. Lansac-Toha, Michael J. Lemke Sep 2016

A Global Edna Comparison Of Freshwater Bacterioplankton Assemblages Focusing On Large-River Floodplain Lakes Of Brazil, Michael Tessler, Mercer R. Brugler, Rob Desalle, Rebecca Hersch, Luiz Felipe M. Velho, Bianca T. Segovia, Fabio A. Lansac-Toha, Michael J. Lemke

Publications and Research

With its network of lotic and lentic habitats that shift during changes in seasonal connection, the tropical and subtropical large-river systems represent possibly the most dynamic of all aquatic environments. Pelagic water samples were collected from Brazilian floodplain lakes (total n = 58) in four floodpulsed systems (Amazon [n = 21], Araguaia [n = 14], Paraná [n = 15], and Pantanal [n = 8]) in 2011–2012 and sequenced via 454 for bacterial environmental DNA using 16S amplicons; additional abiotic field and laboratory measurements were collected for the assayed lakes.We report here a global comparison of the bacterioplankton makeup of freshwater …


Current Knowledge Of Studies Of Pathogens In Colombian Mammals, Viviana Gonzalez-Astudillo, Héctor E. Ramírez-Chaves, Joerg Henning, Thomas R. Gillespie Sep 2016

Current Knowledge Of Studies Of Pathogens In Colombian Mammals, Viviana Gonzalez-Astudillo, Héctor E. Ramírez-Chaves, Joerg Henning, Thomas R. Gillespie

MANTER: Journal of Parasite Biodiversity

Mammals provide an important ecological habitat or niche space to microbial diversity, protistans (or protozoans) and metazoan parasites that can have profound effects on both human and animal health. Thus, understanding the status of mammalian species as hosts for pathogens holds relevance, especially during this time of anthropogenic environmental change. Despite the great diversity in the mammal fauna of Colombia, data in the literature on the occurrence of parasites and pathogens in these mammals are scarce and widely scattered. In order to understand the state of the knowledge of pathogens carried by wild mammals in Colombia, a systematic review of …


A Quantitative Analysis Of Hugelkultur And Its Potential Application On Karst Rocky Desertified Areas In China, Megan Laffoon Aug 2016

A Quantitative Analysis Of Hugelkultur And Its Potential Application On Karst Rocky Desertified Areas In China, Megan Laffoon

Mahurin Honors College Capstone Experience/Thesis Projects

A type of environmental degradation, karst rocky desertification (KRD) refers to areas where the soil loss exposes the bedrock and reduces the land’s ability to sustain life and is particularly widespread through the vast karst area of rural southwest China. Hugelkultur is a permaculture method that harnesses the wood decomposition process by burying logs beneath soil. We proposed that hugel beds will demonstrate a higher water holding capacity and enhance soil development, in a way that may show promise as a potential method to help alleviate problems of KRD. Soil samples were taken from hugel plots, non-hugel plots, and KRD-like …


Urban Ecology In North Texas: Native Plants And Nitrogen Deposition, Michelle Lynn Green Aug 2016

Urban Ecology In North Texas: Native Plants And Nitrogen Deposition, Michelle Lynn Green

Biology Dissertations - Archive

Globally, the human population continues to grow and move into urban areas causing a range of effects on local ecosystems. Elevated temperatures, altered hydrology, and higher concentrations of atmospheric pollutants in urban environments create novel conditions for resident organisms. My research focused on one particular aspect of human alteration to urban environments – nitrogen (N) deposition – and its effects on native plants across an urban to rural gradient in the southern Great Plains, North Texas (NTX), USA. Nitrogen oxides (NOx) – the product of combustion and precursor to nitrate deposition in precipitation – were significantly positively correlated with impervious …


Microbes In Rough Rice – Prevalence, Growth Kinetics And Links To Dry Matter Loss, Supriya Thote Aug 2016

Microbes In Rough Rice – Prevalence, Growth Kinetics And Links To Dry Matter Loss, Supriya Thote

Graduate Theses and Dissertations

The prevalence of microorganisms on freshly-harvested long-grain hybrid, long-grain pureline, and medium-grain rice has not been elucidated. The first objective of this two-part study was to determine the relative prevalence of microbes on freshly-harvested, high moisture content rice of different types and cultivars. The total and surface aerobic plate counts (APC) and mold counts were determined in terms of log10 colony forming units per gram of rice (log10 CFU/g) for six rice cultivars over two years. In 2013, among harvested samples of all the studied rice cultivars, the long-grain hybrid cultivars had the lowest APC levels (M = 8.10, SD …


Shifts In Myxomycete Community Structure In Selected Microhabitats Across Nutrient Treatments In A Lowland Tropical Forest Of Panama, Laura M. Walker Aug 2016

Shifts In Myxomycete Community Structure In Selected Microhabitats Across Nutrient Treatments In A Lowland Tropical Forest Of Panama, Laura M. Walker

Graduate Theses and Dissertations

Myxomycetes (plasmodial slime molds) are abundant amoeboid predators of bacteria and other microorganisms. They are found worldwide, largely in association with decaying plant material in terrestrial habitats. Their consumption of bacterial prey puts microbial predators such as myxomycetes in a key position in various ecosystem processes wherein they help regulate the flow of nutrients (e.g., N and C) through the ecosystem. The importance of microbial predators in nutrient cycling and plant productivity is well established. Given the extent to which tropical ecosystems influence global nutrient fluxes, along with the ecologically significant role that myxomycetes play in these processes, there is …


Stream Microbial Communities As Potential Indicators Of River And Landscape Disturbance In North-Central Arkansas, Wilson Howard Johnson Aug 2016

Stream Microbial Communities As Potential Indicators Of River And Landscape Disturbance In North-Central Arkansas, Wilson Howard Johnson

Graduate Theses and Dissertations

In the past decade, 29 shale basins have been actively developed across 20 states for extraction of natural gas (NG) via horizontal drilling/hydraulic fracturing (=fracking). This includes ~5000 wells within the Fayetteville shale of north-central Arkansas. Development often impacts both river- and landscapes, and management requires catchment-level evaluations over time, with organismal presence/absence as indicators. For this study next-generation sequencing was used to identify/characterize microbial communities within biofilm of eight Arkansas River tributaries, so as to gauge potential catchment influences. Streams spanned a gradient of landscape features and hydrological flows, with four serving as ‘potentially impacted catchment zones’ (PICZ) and …