Digital Commons Network^™

Climate Interactions Drive Tree Physiology And Growth In A Northeastern Forest Ecotone, Alexandra M. Barry

Electronic Theses and Dissertations

Climate change is a threat to global forest ecosystems. In the northeastern United States, forest trees are facing rising temperatures and increasingly inconsistent moisture regimes. In addition to long-term changes in climate conditions, there is concern about the potential for more frequent and intense climate extremes, which can have severe and rapid negative effects on tree physiology and growth. Further, climate extremes may co-occur to produce a greater magnitude of effect than the sum of their parts, with a prominent example being hot droughts, which are increasing in occurrence and severity. The impact of these and other extreme climate interactions …

An Analysis Of The Effect Of Temperature On Asphalt Paving In South Dakota, S M Rahat Rashedi

Electronic Theses and Dissertations

Temperature is an important parameter to consider for asphalt paving since this work is generally susceptible to weather due to outdoor construction. The South Dakota Department of Transportation (SDDOT) developed working day weather charts in 1998 to address the expected adverse weather days. This thesis investigated the effect of temperature on adverse weather days for asphalt paving and compared them to the value reported in the 1998 SDDOT study. Moreover, the thesis also examined how closely the maximum temperature data from project sites' weekly progress reports (WPR) matched the data from the closest weather stations. When the maximum temperature (TMAX) …

Influence Of Environmental Conditions On Assessment Of Fish Communities In Two Lake Erie Coastal Wetlands, Nathan Tuck

Electronic Theses and Dissertations

Wetlands of the Laurentian Great Lakes are diverse ecosystems that support a species rich flora and fauna. Fishes are especially important indicators of wetland productivity and ecological condition. Their distribution is controlled by water quality, water temperature and dissolved oxygen concentration and local habitat (depth, substrate, and local vegetation). Thus, weather-driven exchanges of water between a coastal wetland and the adjacent lake can influence the estimates of the composition and relative abundance of fishes.

I investigated the interactions among wind metrics and water level, water temperature and dissolved oxygen in two Lake Erie protected wetlands with fish abundance and community …

Aggregation Dynamics Of Bulk Nanoparticle Haloing Systems And The Influence Of Non-Ambient Temperatures., Marzieh Moradi

Electronic Theses and Dissertations

One of the methods of assembling colloids into 3D crystal structures is through the use of nanoparticle haloing. Nanoparticle haloing is a stabilization mechanism in binary particle suspensions possessing both a size and charge asymmetry, with which the nanoparticles aid in the bulk suspension’s stability. By altering the volume fractions of nanoparticles, it is possible to control the effective repulsion between the microparticles. Understanding the colloidal interactions and aggregate crystallinity as a function of nanoparticle concentration, temperature, and time are key challenges in developing future materials and designing crystalized 3D colloidal systems. In this study, we investigated the effect of …

Determining The Influence Of Lateral Margin Mechanical Properties On Glacial Flow, Kate Hruby

Electronic Theses and Dissertations

The lateral margins of glaciers and ice streams play a significant role in glacial flow. Depending on their properties, like temperature and ice crystal orientation, they can cause a resistance to flow or enhance it. In combination with our current changing climate, flow patterns can dictate the mass balance of an ice body. It is therefore more important than ever to understand the impact that variations at the margins can have on flow. However, the lateral margins of glaciers and ice streams are an often-neglected part of ice dynamics; they are harder to sample than the center of a glacier’s …

Temperature Effects On Helium Filled Soap Bubble Particle Tracking Velocimetry., Michael C. Blum

Electronic Theses and Dissertations

Helium Filled Soap Bubble (HFSB) Particle Tracking Velocimetry (PTV) methods are becoming increasingly popular as they provide a low cost, safe option for reliable flow visualization. Several studies have been conducted to understand the accuracy of such systems under normal temperatures and pressures; however, no such studies to date have examined accuracy of HFSB PTV at high temperatures. The goal of this study is to characterize the capability of HFSB PTV methods to visualize air flow through a rectangular duct at elevated temperature. A heated wind tunnel was designed to heat up to 150 m³/h of 25 °C …

Impact Of Human Disturbance On The Behavior And Physiology Of The Endangered Ringed Sawback Turtle (Graptemys Oculifera), Jessica Mary Heppard

Electronic Theses and Dissertations

Turtles are one of the most threatened taxa worldwide. In addition to direct anthropogenic impacts such as hunting and pollution, unintentional indirect human disturbance affects poikilothermic turtles by disrupting thermoregulatory basking behavior. In this thesis I assess the behavioral and physiologic impacts of high boat traffic, reductions of basking structures, and environmental factors on basking behavior, rates of disturbance, thermoregulation, parasite load, shell condition, and population recruitment in two populations of the endangered ringed sawback (Graptemys oculifera), also known at the ringed map turtle, on the Pearl River outside Jackson, MS. Basking behavior was influenced by availability of basking structures, …

Abiotic And Biotic Factors Influence Refuge Use At The Community And Organismal Level, George Todd

Electronic Theses and Dissertations

Animal behavior is influence by a wide range of factors. One factor that can heavily influence behavior is the presence or absence of refuge (i.e., refuge provides a direct benefit to animals’ fitness). Many animals seek refuge to avoid predation despite clear costs to other life processes. The decision to use refuge is complex and anthropogenic activities may alter the abundance of refuge. Artificial refuge structures can be successful in conservation efforts and are an effective means to measure biodiversity. Thus, I used cover boards to examine how habitat structure and season influence vertebrate abundance and diversity in the southeastern …

Using An Ecological Framework To Resolve Issues In Forensic Entomology: Exploring Temperature Mediation Of Species Interactions Within Blow Fly (Diptera: Calliphoridae) Communities, Krystal Rae Hans

Electronic Theses and Dissertations

The blow flies Lucilia sericata Meigen, Phormia regina Meigen and Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae) are important decomposers that specifically colonize carrion. Adult flies must make oviposition decisions that impact the survival of their offspring and may be influenced by abiotic and biotic conditions. Although a great deal of research has been conducted regarding their development under different environmental conditions, the influence of species interactions has been scarcely investigated. The objective of my dissertation was to examine the effects of temperature, relative humidity and species interactions on the oviposition behaviour and development of these blow flies.

The Effects Of Stressors And Stress Hormones On Behavior, Physiology, And Disease Susceptibility In Terrestrial Salamanders, Christopher Fonner

Electronic Theses and Dissertations

Amphibians are exposed to numerous environmental stressors, which may contribute to population declines being experienced by amphibians worldwide. Upon exposure to stressors, animals will release the glucocorticoid hormone, corticosterone (CORT), which typically mediates physiological and behavioral responses for resisting or coping with the stressor. Additionally, amphibians are at risk from a chytrid fungal pathogen, Batrachochytrium dendrobatidis (Bd). After Bd infection, amphibians may develop the potentially fatal disease chytridiomycosis. To better understand how CORT mediates responses to different stressors, and possible immunosuppressive effects of CORT on Bd susceptibility, I performed several experiments. First, I tested the predation stress hypothesis in terrestrial …

Multi-Physics Model Of Key Components In High Efficiency Vehicle Drive, Shao Hua Lin

Electronic Theses and Dissertations

Hybrid Electric Vehicles (HEVs) and Electric Vehicles (EVs) are crucial technologies for the automotive industry to meet society’s demands for cleaner, more energy efficient transportation. Meeting the need to provide power which sustains HEVs and EVs is an immediate area of concern that research and development within the automotive community must address. Electric batteries and electrical motors are the key components in HEV and EV power generation and transmission, and their performance plays very important role in the overall performance of the modern high efficiency vehicles. Therefore, in this dissertation, we are motivated to study the electric batteries, interior permanent …

Zooplankton In Freshwaters : Potential Responses To Global Warming, Nutrient Enrichment, And Exotic Jellyfish., Allison S. Smith

Electronic Theses and Dissertations

Aquatic ecosystems face major transformations as humans increasingly alter their environment by introducing exotic species and changing the temperature regime and nutrient availability of freshwater systems. The impacts of such alterations of conditions, resources and species composition on zooplankton are important to consider because zooplankton link primary producers to higher trophic levels. Among recent exotic invaders of freshwater systems in Europe and the Western Hemisphere is Craspedacusta sowerbii. This freshwater cnidarian can impact zooplankton abundance and community composition, thus altering ecosystem energy transfer to higher trophic levels. In experiments described in chapters 2 and 3 of this dissertation, C. sowerbii …

Adaptive Tolerance To Ocean Acidification In The Marine Sponge: Chondrilla Nucula, Sylvester Lee

Electronic Theses and Dissertations

The dramatic increase in atmospheric carbon dioxide since the Industrial Revolution has led to a 30% increase in ocean acidification over pre-industrial levels. Although most ocean acidification research thus far has focused on calcifying organisms such as corals, the potential of this increase in acidity (H+ ions) to cause acid-base imbalances in soft-bodied animals such as sponges has been grossly overlooked. Furthermore, many studies on ocean acidification have not considered the elevated temperatures that are predicted to accompany future climate change conditions. Sponges are crucial components to coral reef systems, providing food, nutrients, structure, and support. The sponge Chondrilla nucula …

Determination Of Selected Heavy Metals In Some Creeks In A Tennessee City., Ann Ejimole Item

Electronic Theses and Dissertations

Concentrations of Ni, Cu, Zn, Fe, Cd, and Pb were determined in six different creeks within a city in Tennessee using Atomic Absorption Spectrophotometer. Mean concentrations of Ni, Cu, Zn, Cd, Pb, and Fe in the sites examined reveal that they exceed the USEPA recommended limits. High concentrations of Cu (0.130 mg/L), Zn (13.7 mg/L), Ni (0.267 mg/L), and Cd (0.010 mg/L) were observed in site B and Fe (3.01 mg/L) in site E relative to other sites. The concentration of Pb (0.795 mg/l) was higher in site A. Higher concentrations of Cu, Zn, and Fe were detected in samples …

The Development Of Scalable Pump Techniques For Gg Iag Fiber Lasers And Passive Athermalization Techniques For Solid State Laser, William Hageman

Electronic Theses and Dissertations

This dissertation consists of two parts: research pertaining to the development of scalable pump techniques for gain guided index-antiguided fiber lasers and research relating to the development of passive athermalization schemes for solid state lasers. The first section primarily details the development of a side pump scheme that allows for power scaling of gain-guided index anti-guided fibers. While these fibers have been demonstrated in past research, none have used a pump technology capable of pumping with the efficiencies, uniformity, and necessary length to allow for scaling of the fiber lasers to high output powers. The side pumped scheme developed in …

A Kinetics Study Of Selected Filtration Media For Nutrient Removal At Various Temperatures, Elizabeth Henderson

Electronic Theses and Dissertations

In recent years the nutrient levels of the Upper Floridan aquifer have been increasing (USGS, 2008). An example of this is found in Ocala, Florida where Silver Springs nitrate concentrations have risen from 0.5 mg/L in the 1960 s to approximately 1.0 mg/L in 2003 (Phelps, 2004). Because stormwater is a contributor to surficial and groundwater aquifer recharge, there is an increasing need for methods that decrease nitrogen and phosphorus levels. A laboratory column study was conducted to simulate a retention pond with saturated soil conditions. The objectives of the column studies reported in this thesis were to investigate the …

Temperature Inside The Landfill: Effects Of Liquid Injection And Ambient Temperature, Amit Kumar

Electronic Theses and Dissertations

This study represents an analysis of comprehensive temperature and moisture content data collected from the anaerobic portion of a bioreactor landfill at the New River Regional Landfill, Florida, USA. The main focus of the study was the analysis of effects of the liquid injection on the temperature inside the landfill. When the leachate or groundwater at lower temperature than the landfilled waste is injected into the landfill, it has an initial cooling effect on the waste until the biological activity, enhanced by the additional moisture, releases heat. This cooling effect was tested in the study to determine whether it could …

Temperature Conditions At Orono, Maine, Ernest Claude Drew

Electronic Theses and Dissertations

This thesis is an outgrowth of a much larger piece of work which the Department of Physics, thru its instructors and major students, has undertaken to complete. The task referred to, is the compilation, arrangement, and summarizing of the various meteorological records taken at the University of Maine for the past forty-four years. These records were begun in the above department by Dr. M. C. Fernald in the year 1869 and were continued by him until 1893. The work was then transferred to the Experiment Station, where observations were made under the direction of Doctors W. H. Jordan and C. …