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Influence Of Resource Availability On Juniperus Virginiana Expansion In A Forest–Prairie Ecotone, A. C. Ganguli, D. M. Engle, P. M. Mayer, L. F. Salo

United States Environmental Protection Agency: Publications

Woody plant expansion into grasslands and savannas is a global concern. Rapid expansion of Juniperus virginiana, a tree native to North America, has profound ecological consequences. We used transplanted J. virginiana seedlings to investigate the role of resource availability on J. virginiana expansion following the removal of fire, the factor historically limiting range expansion of this fire-intolerant species. We evaluated J. virginiana seedling survival and seedling growth, two important phases in woody plant expansion, relative to two below ground resource factors, plant-available soil water (soil clay content, an index of plant-available soil water) and plant-available nitrogen (PAN), and an above …

The Role Of Organic Matter In The Fate And Transport Of Antibiotic Resistance, Metals, And Nutrients In The Karst Of Northwest Arkansas, Victor Lee Roland Ii

Graduate Theses and Dissertations

Organic matter (OM) in the environment acts as a nutrient, but may also act as a transport vector for harmful chemical compounds and bacteria. Acetate is a labile form of OM produced during fermentation in anaerobic lagoons used to store animal fecal-waste from concentrated animal feeding operations (CAFOs). Dry and liquid fertilizers from CAFOs pose a threat to groundwater by introducing excessive amounts of nutrients (e.g. OM, nitrate and ammonia), metals, and antibiotic compounds. In the epikarst of Northern Arkansas in the Buffalo River watershed additional input of labile dissolved organic carbon (DOC) from liquid CAFO waste-fertilizers was hypothesized to …

Optical Water Quality And Human Perceptions Of Rivers, Amie West

Graduate Theses and Dissertations

Understanding water quality dynamics in recreational rivers is integral in shaping management strategies that maintain ecosystem health, perceived value and appeal, and regional economic significance in a changing environment. Optical water quality describes the behavior of light in water as governed by its physical and chemical composition, and is among the strongest influences on human perceptions of water quality. Ethnohydrology is the study of culturally constructed knowledge and understanding of water. This work is the culmination of an interdisciplinary approach to water resources research—integrating optical water quality and ethnohydrology methods to recognize the intersection between measured water quality and visible …

Simulation Of Flow And Water Quality From Tile Drains At The Watershed And Field Scale, Colleen Moloney

Open Access Theses

Simulation models such as the Soil and Water Assessment Tool (SWAT) have become widely used in determining the water quality impacts of various management practices. Ensuring that the algorithms accurately represent the processes simulated has become an important goal. Tile drainage is a standard practice in the Midwest, US in order to reduce risk of yield loss due to excess water. Multiple tile drainage and water table algorithms have been available in the SWAT model between the initial SWAT release and revision 638 used in this study. Testing of those algorithms is often limited. Furthermore, algorithms in the current version …

Resilience And Heterogeneity Following Fire In The Nebraska Sandhills, Jack R. Arterburn

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

The Nebraska Sandhills grassland is an expansive, semi-arid ecosystem characterized by vegetation-stabilized rolling sand dunes. The Sandhills grassland is managed for livestock production by seeking to minimizing disturbances, such as fire, that increase bare ground. The increase in bare ground following fire has contributed to the fear of fire leading to the emergence of a mobile sand dune state. We tracked vegetation response following a growing season wildfire that occurred during extreme drought conditions. In wildfire and drought conditions are when one would expect resilience to be overcome leading to a lack of vegetation recovery and a transition to a …

Identifying And Addressing Soil Property Issues Affecting Roadside Vegetation Establishment, Xu Li, Martha Mamo, Walter H. Schacht, Tala Awada, Humberto Blanco-Canqui

Nebraska Department of Transportation: Research Reports

Attaining adequate vegetation cover along highways is important for NDOR to comply with EPA’s stormwater regulations. However, low plant cover is a common problem on shoulders (first 16 feet off the pavement) of many highways in Nebraska. The ultimate goal of this study is to identify cost-effective engineering solutions that assure adequate seed beds (i.e., soil conditions) for establishment of selected seeding mixtures. The objectives of this study are to (1) characterize the soil properties along roadsides where vegetation stands have not developed well, and (2) verify the effects of select soil property parameters on plant germination and establishment.

Sampling …

South Padre Island Beach Management: Assessment Of Dune Restoration, Shelby Rose Bessette

Theses and Dissertations

Dune restoration is a common method of increasing coastal resilience. A dune restoration program was initiated by the City of South Padre Island, TX in 2010 consisting primarily of plantings of Sea Oats, Uniola paniculata, and Bitter Panicum, Panicum amarum and has continued approximately annually thereafter. These restoration efforts were evaluated in this study by comparing dune ecological structure and function among reference sites and restoration plots ranging in age from 2 to 5 years. Plant and animal communities were examined using a combination of quadrat sampling, funnel traps, pit-falls and sweep nets. Soil organic content and soil electric …

Evaluating A Measure-Calculate Method For Determining Sediment Oxygen Demand In Lakes, Adrian Beirise

Graduate Theses and Dissertations

A steady-state mass diffusion model used with simple measurable and calculable inputs for determining sediment oxygen demand (SOD) is compared to an intact core incubation (ICI) SOD method using samples from three lakes. The mass diffusion model coupled with inputs is known as the measure-calculate method (M-C) and is a potential alternative to existing methods for measuring SOD which are more complex, time-consuming, and costly. The M-C method requires inputs for volumetric sediment oxygen uptake (Ṅsed), sediment density and porosity, and water properties. Ṅsed was determined by suspending sediment in oxygen-saturated water with a DO probe and determining the steady …

Determination Of Optimum Fall And Spring Nitrogen Fertilizer Rate For Maximizing Grain Yield Of Soft Red Winter Wheat Sown At Variable Planting Dates, Lucas Vasconcelos Vieira

Graduate Theses and Dissertations

An optimum planting date is important for winter wheat nitrogen (N) management as it dramatically changes the growing environment including temperature and moisture, ultimately affecting fertilizer efficiency and grain yield (GY). In Arkansas, high precipitation in the fall often forces farmers to delay planting and current Arkansas recommendations include the application of fall N when soft red winter wheat (SRWW) is sown later than optimum, despite the lack of data supporting this practice. This study evaluated the effect of rate and timing of N application on GY of SRWW sown at variable planting dates in Arkansas. Granular urea was split …

Chlorine Demand Shows Thresholds And Hierarchy With Source Water Quality At Beaver Lake, Arkansas, Jaime M. Gile

Graduate Theses and Dissertations

This study investigated the effects of source water quality in Beaver Lake on the amount of chlorine (Cl) needed to develop decision support system to help guide chlorination practices in pre-treatment of source water. Chlorine demand assays were performed on water samples from Beaver Lake collected from the intake structure at Beaver Water District from March 2014 through August 2015, and using data from these assays, the two points of interest in this study were the Cl dose at which Cl residuals began to accumulate and the mean Cl demand occurring after that dose. Three methods of analysis were used …

A Tribute To Thomas M. Church: Exploring Chemical Oceanography In The Coastal Zone-The History And Future, Gregory A. Cutter, David J. Burdige

OES Faculty Publications

(First paragraph) One can find different historical perspectives on the development of studying the chemistry of oceans as well as names for this study—marine chemistry, chemistry of the sea, marine aquatic chemistry, marine biogeochemistry, or chemical oceanography. It could be argued that chemical oceanography is the most inclusive for an earth science since oceanography itself is an integrated discipline that links the biology, chemistry, geology, and physics together. Regardless of the name, perhaps the first intensive, modern/post-nineteenth century study of the ocean’s chemistry was the GEOSECS Program from ca. 1970–1978. The significance of GEOSECS was that it examined the chemistry …

Validation Of N-Star Nitrogen Rate Recommendations And Evaluation Of N-Star Soil Sampling Procedures For Clay Soils In Arkansas, Jarom Thane Davidson

Graduate Theses and Dissertations

The two methods for determining N-fertilizer recommendations for rice (Oryza sativa L.) in Arkansas are the standard N recommendation (SR) based on soil texture, previous crop, and rice cultivar, and the Nitrogen-Soil Test for Rice (N-STaR) which quantifies the potentially mineralizable-N of the soil and provides a site-specific N recommendation. The N-STaR program has recently been developed, and the validation of N-STaR for clay soils is an important step in ensuring that N-STaR predicts correct N-fertilizer rates for rice under a delayed-flood production system. Small-plot trials located across Arkansas compared the N-STaR 95 and 100% relative grain yield (RGY) N …

Pore Characterizations And Distributions Within Niagaran – Lower Salina Reef Complex Reservoirs In The Silurian Northern Niagaran Pinnacle Reef Trend, Michigan Basin, Agam Arief Suhaimi

Masters Theses

The Northern Niagaran Pinnacle Reef Trend (NNPRT) has generated significant oil and gas production in Michigan. The best reservoir rock in the Reef Trend reservoirs are from porous and permeable dolomite of the Guelph Dolomite. Low-to-non reservoir limestone occurs interstratified with reservoir dolomite in many locations. This study utilizes available cores data, thin section Petrographic Image Analysis (PIA), Mercury Injection Capillary Pressure (MICP) and a newly developed Niagaran Reef depositional model (Rine, 2015) to characterize the distribution of pore geometry within each dolomitized Niagaran Reef Complex (Brown Niagaran – Lower Salina Group) reservoir facies and lithofacies. This study shows that …

Determining The Viability Of Recent Storms As Modern Analogues For North-Central Gulf Of Mexico Paleotempestology Through Sedimentary Analysis And Storm Surge Reconstruction, Joshua Caleb Bregy

Master's Theses

The northern Gulf of Mexico has been devastated by recent intense storms. Camille (1969) and Katrina (2005) are two notable hurricanes that made landfall in virtually the same location in Mississippi. However, fully understanding the risks and processes associated with hurricane impacts is impeded by a short and fragmented instrumental record. Paleotempestology could potentially use modern analogues from intense storms in this region to extend the hurricane record back to pre-observational time. Existing empirically based models can back-calculate surge heights over coastal systems as a function of transport distance, particle settling velocity, and gravitational acceleration. We collected cores in a …

Spread Of Tylodelphys Mashonense (Digenea: Diplostomidae) By Grey Heron Ardea Cinerea And Great White Egret A. Alba In Lake Victoria, Tanzania, Fred D. Chibwana, Gamba Nkwengulila

Tanzania Journal of Science

Despite the fact that Tylodelphys mashonense, parasites of the cranial cavity of the catfish Clarias gariepinus, are ubiquitous in freshwater systems, little is known on their spread. As such, we examined a total of 152 piscivorous birds, belonging to 6 species; 43 great cormorant Phalacrocorax carbo, 33 grey heron Ardea cinerea, 26 hamerkop Scopus umbretta, 22 great white egret Ardea alba, 15 marabou stork Leptoptilos crumeniferus and 13 pied kingfisher Ceryle rudis foraging in the Lake Victoria. Out of the six bird species only A. cinerea and A. alba were found infected by T. mashonense with prevalence of 42.4% and …

Effects Of Shoreline Dynamics On Saltmarsh Vegetation, Shailesh Sharma, Joshua Goff, Ryan M. Moody, Ashley Mcdonald, Dorothy Byron, Kenneth L. Heck Jr., Sean Powers, Carl Ferraro, Just Cebrian

University Faculty and Staff Publications

We evaluated the impact of shoreline dynamics on fringing vegetation density at mid- and low-marsh elevations at a high-energy site in the northern Gulf of Mexico. Particularly, we selected eight unprotected shoreline stretches (75 m each) at a historically eroding site and measured their inter-annual lateral movement rate using the DSAS method for three consecutive years. We observed high inter-annual variability of shoreline movement within the selected stretches. Specifically, shorelines retrograded (eroded) in year 1 and year 3, whereas, in year 2, shorelines advanced seaward. Despite shoreline advancement in year 2, an overall net erosion was recorded during the survey …

A R2r3-Myb Transcription Factor Regulates The Flavonol Biosynthetic Pathway In A Traditional Chinese Medicinal Plant, Epimedium Sagittatum, Wenjun Huang, A. B. M. Khaldun, Jianjun Chen, Chanjuan Zhang, Haiyan Lv, Ling Yuan, Ying Wang

Plant and Soil Sciences Faculty Publications

Flavonols as plant secondary metabolites with vital roles in plant development and defense against UV light, have been demonstrated to be the main bioactive components (BCs) in the genus Epimedium plants, several species of which are used as materials for Herba Epimedii, an important traditional Chinese medicine. The flavonol biosynthetic pathway genes had been already isolated from Epimedium sagittatum, but a R2R3-MYB transcription factor regulating the flavonol synthesis has not been functionally characterized so far in Epimedium plants. In this study, we isolated and characterized the R2R3-MYB transcription factor EsMYBF1 involved in regulation of the flavonol biosynthetic pathway …

A Molluscan Record Of Monsoonal Precipitation Along The Western Shoreline Of The Late Maastrichtian Western Interior Seaway, Scott Allen Ishler

USF Tampa Graduate Theses and Dissertations

Global warming in response to increasing levels of atmospheric CO2 concentration (pCO₂) has generated concern over the effects of increasing surface temperature on the hydrologic cycle. Investigating precipitation dynamics during past ‘greenhouse’ intervals provide important insights necessary to better constrain potential future climate scenarios. The Late Cretaceous greenhouse is characterized by elevated pCO₂ and surface temperatures, with a prolonged cooling trend which initiated in the late Campanian and an associated 4^th-order sea-level regression recorded in the Western Interior Seaway (WIS), providing an opportunity to examine the hydrologic cycle under conditions of changing temperature and sea-level. …

Variation In Tussock Architecture Of The Invasive Cordgrass Spartina Densiflora Along The Pacific Coast Of North America, Jesus M. Castillo, Brenda J. Grewall, Andrea Pickart, Enrique Figueroa, Mark D. Sytsma

Environmental Science and Management Faculty Publications and Presentations

Some introduced species spread rapidly beyond their native range and into novel habitats mediated by a high degree of phenotypic plasticity and/or rapid evolutionary responses. In this context, clonality has been described as a significant factor contributing to invasiveness. We studied the abiotic environment and the responses of different tussock architecture traits of the invasive cordgrass Spartina densiflora Brongn. (Poaceae). A common garden experiment and field studies of S. densiflora in salt marshes across a wide latitudinal gradient from California (USA) to British Columbia (Canada) provided a model system for an integrated study of the potential mechanisms underlying the response …

A Survey Of Weed Varieties In Samanabad, Lahore, Sadaf Nazir, Beenish Zia Butt, Anjum Navid

Journal of Bioresource Management

A weed is an herbaceous plant that grows as a wild plant, and is considered a hindrance in the growth of preferred vegetation or cumbering the ground, and has no value for beauty or use. However, some weeds have roles in medicine, ecology and many other fields. A survey was conducted in Lahore to observe the weed varieties present in the area of Samanabad. The present study was carried out in May and June 2014.The primary purpose of the study was to gain knowledge about the availability of the total number of species present in this area. We also assessed …

Soil Extracellular Enzyme Activities, Soil Carbon And Nitrogen Storage Under Nitrogen Fertilization: A Meta-Analysis, Siyang Jian, Jianwei Li, Ji Chen, Gangsheng Wang, Melanie A. Mayes, Kudjo E. Dzantor, Dafeng Hui, Yiqi Luo

Agricultural and Environmental Sciences Faculty Research

Nitrogen (N) fertilization affects the rate of soil organic carbon (SOC) decomposition by regulating extracellular enzyme activities (EEA). Extracellular enzymes have not been represented in global biogeochemical models. Understanding the relationships among EEA and SOC, soil N (TN), and soil microbial biomass carbon (MBC) under N fertilization would enable modeling of the influence of EEA on SOC decomposition. Based on 65 published studies, we synthesized the activities of α-1,4-glucosidase (AG), β-1,4-glucosidase (BG), β-d-cellobiosidase (CBH), β-1,4-xylosidase (BX), β-1,4-N-acetyl-glucosaminidase (NAG), leucine amino peptidase (LAP), urease (UREA), acid phosphatase (AP), phenol oxidase (PHO), and peroxidase (PEO) in response to N fertilization. The proxy …

Evaluating The Influences Of Karst Hydrogeology On Freshwater Harmful Algal Blooms In Kentucky Lakes, Robert T. Schaefer

Masters Theses & Specialist Projects

A problem exists in Nolin River Lake and Rough River Lake in Kentucky, due to the increasing prevalence of cyanobacterial-based harmful algal blooms (CyanoHABs) and the threats they pose to local communities. These lakes were developed as artificial reservoirs from embankment. Further complicating the issue, the lakes are located within a heavily karstified region and there exists no plan or method currently for monitoring or managing CyanoHABs in a karst region with regard to groundwater inputs to the lake systems or their tributaries. A mixture of techniques and analysis methods was used to determine the best way to monitor and …

Determining Groundwater Sources And Ages Via Isotope Geochemistry In Big Sky, Montana, Thomson Connie

Graduate Theses & Non-Theses

The Big Sky ski resort area in southwestern Montana is experiencing exponential growth in both development and population. Concerns have arisen over the quantity of good-quality groundwater in the region, and whether there is a large enough reserve to support the growing demand. In light of already-documented water-level decreases, and domestic wells needing to be deepened or replaced, the Montana Department of Natural Resources and Conservation (DNRC) enlisted the Montana Bureau of Mines and Geology's Ground Water Investigation Program to perform an assessment of groundwater availability and quality in the region, and define groundwater supply sources.

The geology in the …

Dental Microwear Variation In Teleoceras Fossiger (Rhinocerotidae) From The Miocene (Hemphillian) Of Kansas, With Consideration Of Masticatory Processes And Enamel Microstructure, Kelsie Abrams

Master's Theses or Doctor of Nursing Practice

Dental microwear analysis is the study of microscopic features on the surfaces of teeth, and is used to reconstruct and analyze diet in extinct and extant animals. Microwear analysis on ungulates is typically conducted on the paracone or protoconid of the second molar, as these cusps are usually the first point of contact between upper and lower teeth during the chewing stroke. However, the exact method of mastication varies in different groups of ungulates, and the influence of mastication on the location and production of microwear features has been studied very little. Additionally, the role of highly specialized enamel microstructure …

Reconstructing The Paleoecology And Biogeography Of Rhinoceroses (Mammalia: Rhinocerotidae) In The Great Plains Of North America, Leading Up To Their Extinction In The Early Pliocene, Bian Wang

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Members of the family Rhinocerotidae first appeared in the middle Eocene and were one of most successful mammal groups of the Oligocene and Miocene in North America. Their extinction in the early Pliocene has been attributed to several causes, including cooling climate, an expansion of C₄ grasslands, and faunal turnover favoring high-crowned, open habitat-adapted mammalian taxa. This study tests whether the extinction of North American rhinoceroses in the Great Plains was abrupt or gradual by examining changes in their paleogeographic distribution in a series of time-slices through the Barstovian, Clarendonian, and Hemphillian North American land-mammal ages. It further examines …

Assessment Of Indoor And Outdoor Pm Species At Schools And Residences In A High-Altitude Ecuadorian Urban Center, Amit U. Raysoni, Rodrigo X. Armijos, M. Margaret Weigel, Teresa Montoya, Patricia Eschanique, Marcia Racines, Wen-Whai Li

School of Earth, Environmental, & Marine Sciences Faculty Publications

An air monitoring campaign to assess children’s environmental exposures in schools and residences, both indoors and outdoors, was conducted in 2010 in three low-income neighborhoods in Z1(north), Z2(central), and Z3(southeast) zones of Quito, Ecuador - a major urban center of 2.2 million inhabitants situated 2850 meters above sea level in a narrow mountainous basin. Z1 zone, located in northern Quito, historically experienced emissions from quarries and moderate traffic. Z2 zone was influenced by heavy traffic in contrast to Z3 zone which experienced low traffic densities. Weekly averages of PM samples were collected at schools (one in each zone) and residences …

Costimulation Of Soil Glycosidase Activity And Soil Respiration By Nitrogen Addition, Ji Chen, Yiqi Luo, Jianwei Li, Xuhui Zhou, Junji Cao, Rui-Wu Wang, Yunqiang Wang, Shelby Shelton, Zhao Jin, Laura M. Walker, Zhaozhong Feng, Shuli Niu, Wenting Feng, Siyang Jian, Lingyan Zhou

Agricultural and Environmental Sciences Faculty Research

Unprecedented levels of nitrogen (N) have been deposited in ecosystems over the past century, which is expected to have cascading effects on microbially mediated soil respiration (SR). Extracellular enzymes play critical roles on the degradation of soil organic matter, and measurements of their activities are potentially useful indicators of SR. The links between soil extracellular enzymatic activities (EEAs) and SR under N addition, however, have not been established. We therefore conducted a meta-analysis from 62 publications to synthesize the responses of soil EEAs and SR to elevated N. Nitrogen addition significantly increased glycosidase activity (GA) by 13.0%, α-1,4-glucosidase (AG) by …

From Near And Far: Utilization Of In-Situ And Remotely Sensed Satellite Data From Nasa And Noaa, Jessica Rochelle Price Sutton

Theses and Dissertations

Satellite remote sensing observations have been used for numerous studies to better understand physical and biological properties over varying spatial and temporal scales. Depending on the satellite and sensor, the satellite-derived observations can provide high spatial and temporal resolution for many important physical and biological variables. While there are many limitations in utilizing satellite remote sensing products, there are also many advantages. This dissertation investigates three different applications for satellite remote sensing products to address climatological and ecological concerns. This dissertation is motivated by two overall research questions: (1) How can satellite remote sensing products be used to address important …

North American Butterfly Association Counts At Congaree National Park: A Case Study For Connecting Citizen Science To Management, Austin Clarridge

Theses and Dissertations

Citizen science is becoming an ever more popular way for scientists and resource managers to deal with needs for large temporal and spatial scale datasets. It provides a free or low cost means for collection of extensive amounts of data across time and space while acting as a public education and outreach tool, empowering communities to be involved in the management decisions being made in their back yard. Though large, well-known citizen science programs such as the Christmas Bird Counts are being used extensively for peer reviewed literature and management decisions, there are numerous smaller, local counts that have the …

Do Some Deep‐Sea, Sediment‐Dwelling Species Of Harpacticoid Copepods Have 1000‐Km‐Scale Range Sizes?, Erin E. Easton, David Thistle

School of Earth, Environmental, & Marine Sciences Faculty Publications

The range sizes of sediment‐dwelling deep‐sea species are largely unknown. Such knowledge is important because a deep sea composed in large part of species with 100‐km‐scale ranges would be very different from one composed predominantly of species with 1000‐km‐scale ranges. For example, the total species richness would be much greater in the first case than in the second. As a step towards the determination of the distribution of species’ range sizes in the deep sea, we asked whether harpacticoid copepods (Crustacea) on the continental rise in the northeastern Pacific had 1000‐km‐scale range sizes. We chose harpacticoids because they occur widely …