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Multidisciplinary Assessment And Documentation Of Past And Present Human Impacts On The Neotropical Forests Of Petén, Guatemala, Christopher Stephen Balzotti

Theses and Dissertations

Tropical forests provide important habitat for a tremendous diversity of plant and animal species. However, limitations in measuring and monitoring the structure and function of tropical forests has caused these systems to remain poorly understood. Remote-sensing technology has provided a powerful tool for quantification of structural patterns and associating these with resource use. Satellite and aerial platforms can be used to collect remotely sensed images of tropical forests that can be applied to ecological research and management. Chapter 1 of this article highlights the resources available for tropical forest remote sensing and presents a case-study that demonstrates its application to …

Strategies For Deriving A Single Measure Of The Overall Burden Of Antimicrobial Resistance In Hospitals, Alessandro Orlando

Theses and Dissertations

Background: Antimicrobial-resistant infections result in hospital stays costing between $18,000 and $29,000. As of 2009, Centers for Medicare and Medicaid Services no longer upgrade payments for hospital-acquired infections. Hospital epidemiologists monitor and document rates of individual resistant microbes in antibiogram reports. Overall summary measures capturing resistance within a hospital may be useful. Objectives: We applied four techniques (L1- and L2-principal component analysis (PCA), desirability functions, and simple summary) to create summary measures of resistance and described the four summary measures with respect to reliability, proportion of variance explained, and clinical utility. Methods: We requested antibiograms from hospitals participating in the …

Long-Term Spatial And Temporal Variability Of Benthic Macroinvertebrate Communities: Implications For Bioassessment Of Lotic Systems, Eve O'Connor

Theses and Dissertations

The structure and composition of benthic macroinvertebrate communities can vary spatially and over time. Spatial and temporal variation along a stream has many implications for population and community dynamics, which may influence bioassessment programs. I examined variability in the benthic community of eight streams within the Polecat Creek, Virginia watershed. These streams vary in size from 1st to 4th order. The streams were sampled once every season for eleven years using standard bioassessment protocols. Macroinvertebrates were sampled from both sediment and submerged wood habitats at each site. The coefficient of variation (CV) was used to quantify among season, among year …

Assessing Effects Of Land Use On Streams Along The Natchez Trace Parkway Using Rapid Bioassessment Protocol Techniques, Bonnie Laine Earleywine

Theses and Dissertations

Stream quality along the Natchez Trace Parkway was evaluated by hydrologic unit code 4 (HUC4) watersheds and habitat assessment scores as a broad and local scale, respectively. Water chemistry parameters and rapid bioassessment techniques for habitat and fish and invertebrate communities were sampled in 18 streams and six HUC4 watersheds. Forest, agriculture, and developed land use had little variation at HUC4 level; land use impacts could not be determined. Turbidity and TSS were important factors determining habitat scores and created a “boundary” separating southern and northern watersheds. A latitudinal trophic shift was observed of fish omnivoreinsectivore- piscivore in southern watersheds …

Investigating The Relationship Between The Policy Implementation Process And The Utilization Of Information Technology In A Constitutional Republic: The Case Of I-269 Nepa Process, Joseph Hampton Holland

Theses and Dissertations

Information technologies (IT) have provided significant benefits for society. By drawing on the assumptions of the New Public Management (NPM) framework, the author investigates how, in one case, IT alters the policy implementation process. Additionally, the author tests reinforcement theory, sociotechnical theory, and technological determinism to determine which IT model best explains the utilization of IT at the Mississippi Department of Transportation (MDOT). This study examines the National Environmental Policy Act (NEPA) of 1969. By conducting interviews, analyzing documents, and examining a physical artifact, the author explores the administration of an economic impact analysis (EIA) that was conducted on the …

Spatial And Temporal Distribution Of Larval Fishes In A Large Tidal River., Harold Seelig

Theses and Dissertations

There are few published studies of larval fish assemblages from unregulated, tidal freshwater rivers. Patterns in the spatial and temporal distribution of larval fishes in the Mattaponi River were examined. Sampling took place on a weekly basis from February through August, 2006 and 2007. Larval fishes were categorized by taxa, reproductive guild, and residency guild. Group comparisons using multi-response permutation procedures (MRPP) indicated significant spatial and temporal differences in assemblage composition on multiple scales. Differences in assemblage composition were analyzed using non-metric multidimensional scaling (NMS). Interannual differences were attributable to anadromous and semi-migratory species. Seasonal differences were attributable to herrings, …

Diversity And Abundance Of The Dark Kangaroo Mouse, Microdipodops Megacephalus, In Communities Of Nocturnal Granivorous Rodents In Western North America, Ashley Sagers Haug

Theses and Dissertations

The dark kangaroo mouse, Microdipodops megacephalus, is a sensitive species in the Great Basin Desert. This thesis explores the structure of desert rodent communities of the Great Basin to better understand M. megacephalus' place in the community and the conditions that promote large and stable populations. To determine community structure, I used nestedness analysis to evaluate 99 communities of nocturnal granivorous rodents. I found that the community structure was non-random, indicating the existence of assembly rules and ecological constraints. I also found that M. megacephalus was the second most vulnerable species in the community. To explore the correlation …

Taxonomy And Applied Biogeography Of Mongolian Stoneflies (Insecta: Plecoptera), Sarah Walker Judson

Theses and Dissertations

Since the early 1900s, efforts have been made to catalogue the stoneflies of Mongolia. Taxonomic work from 1960 to 1980 greatly expanded basic lists of stoneflies in Mongolia, but no comprehensive survey or synthesis of this dispersed literature has been completed. In conjunction with a modern survey of the aquatic insects of Mongolia, we collected Plecoptera on a series of expeditions to the Selenge (north) and Altai (west) regions of Mongolia. A total of 48 species distributed in 24 genera and 8 families were documented, including 3 of the 5 Mongolian endemics, 2 new species records for Mongolia, and 1 …

Parental Factors As A Moderator Of The Co-Occurrence Of Substance Use And Depression In Hispanic Adolescents, Rebecca Shoff

Theses and Dissertations

The purpose of this study was to evaluate the relationship between parenting factors and Hispanic adolescent substance use and depression. Specifically, the study examined the relationship between parental support, parental knowledge, and parental psychological control among Hispanic adolescents' use of alcohol, tobacco, marijuana, hard drugs and depressive symptoms. The sample included 839 Hispanic (primarily Mexican) 9th – 12th graders from west Texas area school districts who were given a self-reported survey to assess parental behaviors, substance use, and adolescent depression. Using structural equation modeling (SEM), findings indicated that higher levels of maternal support were related to lower levels of depressive …

A Study Of The Relationship Between Proenvironmental Product Use And Environmnetal Concern, Joshua M. Poulton

Theses and Dissertations

To be sustainable, an organization must be balanced in the three principles of economy, environment, and society. Advances in pro-environmental technology have overcome roadblocks limiting the economic and environmental principles. The remaining hurdle to becoming sustainable is having society’s beliefs and behaviors align. Understanding the interaction between an individual’s environmental belief and environmental behaviors is essential to bringing them into alignment. To explore this relationship, a model was developed that included the new ecological paradigm (NEP) scale and a generalized version of the theory of planned behavior (TPB). The attitudes, intentions, and use of six pro-environmental products were measured in …

Biogeochemistry Of Microbial Mats From A Hypersaline Pond And Reef Biofilm From A Modern Coral Reef, The Bahamas, Mary Keith Puckett

Theses and Dissertations

Biofilm communities host complex biogeochemical processes and play a role in the formation of many carbonate rocks by influencing both carbonate precipitation and dissolution. In this study, the biogeochemistry of microbial mats from a hypersaline pond and biofilm from a coral reef are described using SEM, microelectrode profiling, Biolog, fatty acid methyl ester (FAME) and carbon nitrogen analysis. Results show that the microbial mats are distinctly layered, having an oxic upper portion and an H2S-rich lower portion. The most significant conclusions are that the mats have exceptionally high TOC values and display significant differences in microbial communities present, both between …

The Ecological Importance Of Extrinsic And Intrinsic Drivers Of Animal Movement, Josh Earl Rasmussen

Theses and Dissertations

The movement of individuals is foundational to many ecological processes. For example, the movement of an organism from one place to another alters population density at both sites and has potential for affecting the genetic dynamics within the new population. Individual movement events may be in synchrony with overall trends in populations, e.g. spawning migrations, or may be atypical (asynchronous). This latter movement type can affect population and metapopulation dynamics, depending on its prevalence within a population. Nevertheless, given the complexity of interactions, the causative factors of movement are understood vaguely, much less for aquatic organisms. Drivers of movement are …

Detection Of Tick-Borne Bacterial Agents In Lone Star Ticks (Amblyomma Americanum) And Various Wildlife In Mississippi, Ashley Harris Castellaw

Theses and Dissertations

Two studies were conducted to evaluate the presence of tick-borne bacterial agents in Amblyomma americanum, lone star tick (LST), and various wildlife in Mississippi. Adult LSTs had DNA evidence of Ehrlichia chaffeensis (3.7%), E. ewingii (6.3%), and Borrelia lonestari (2.6%), while both larval (24.3%) and adult (43.5%) LSTs were positive for a Rickettsia spp. by polymerase chain reaction (PCR). White-tailed deer (WTD) were the only wildlife PCR positive for E. chaffeensis (18.8%), B. lonestari (3.1%), and Anaplasma phagocytophilum (3.1%). In addition, WTD had the highest seroprevalence to B. lonestari (19.3%) and E. chaffeensis (43.9%) antigens while raccoons had the highest …

Co-Occurrence With A Congeneric Species Predicts Life History And Morphological Diversification In The Mexican Livebearing Fish Poelicopsis Baenschi, Laura E. Scott

Theses and Dissertations

Understanding why some species coexist and others do not remains one of the fundamental challenges of ecology. While several lines of evidence suggest that closely related species are unlikely to occupy the same habitat because of competitive exclusion, there are many cases where closely related species do co-occur. Research comparing sympatric and allopatric populations of co-occurring species provides a framework to understand the role of phenotypic diversification in species coexistence. In this study I focus on the livebearing fish Poeciliopsis baenschi and ask if differences in phenotypic traits among populations can be explained by the presence or absence of the …

Secondary Student And Teacher Perceptions Of Building Relationships For Personalizing Education, Greg S. Grooters

Theses and Dissertations

Increased accountability, due to No Child Left Behind Act (2001), has brought a sharp focus on America's schools. Through school initiatives, yearly progress reports, and testing, public schools continue to identify potential areas of improvement. The study's purpose was to identify the perceptions of high school students and teachers regarding student and teacher relationships effecting the personalization of learning at West Fargo High School. The West Fargo High School teachers and students (grades 9-12) completed parallel on-line surveys in the winter of 2006. All of the students completed the survey on-line with anonymous accounts. The teacher's survey was administered through …

A Comparison Of Two Common Classification Procedures For Economical Urban Land Cover Mapping Using Naip Imagery, Kent Lowell Simons

Theses and Dissertations

Detailed urban land cover maps are increasingly useful and important applications of remote sensing. Municipal agencies and others use land cover maps and data for numerous critical local planning and monitoring functions and for urban geographical research studies. Because of this, there is a demand for accurate urban land cover maps that can be produced quickly and economically. The availability of very high resolution multispectral imagery is an important factor in enabling such production, as the judicious selection of source imagery has a large impact on the resulting map products. Likewise, the implementation of appropriate digital image processing methods is …

The Spatial Demography Of Reported Crime: An Examination Of Urban-Rural Crime Articulation And Associated Spatio-Temporal Diffusion Processes, U.S. 1990 - 2000, Jeremy Reed Porter

Theses and Dissertations

Recently, increased attention has been given to the social and environmental context in which crimes occur (Wells & Weisheit 2004). This new interest in the human ecology of crime is largely demographic, both in terms of subject matter and increasingly in terms of the analytic methods used. Building on existing literature on the social ecology of crime, this study introduces a new approach to studying sub-county geographies of reported crime using existing census place and county definitions coupled with spatial demographic methods. Spatially decomposing counties into Census places and what Esselstyn (1953) earlier called “open country,” or non-places, allows for …

Patterns Of Fish Communities And Limnological Conditions Relative To Floodplain Landscapes, Seiji Miyazono

Theses and Dissertations

The Yazoo River Basin of Mississippi includes several rivers and hundreds of floodplain lakes within an area greatly impacted by agriculture. I studied 17 of these lakes distributed over the lower half of the Yazoo River Basin to document fish assemblages and limnological patterns and to identify environmental variables that might influence these assemblages. Potential connectivity of the lake to parent river and wetland-lake area ratio in the watershed were related to the limnological conditions and fish communities. Lakes with greater potential connectivity tended to be deeper and had greater specific conductance and greater fish species richness including more riverine …

Development Of A Multi-Scale Management Perspective For Wadeable Stream Fisheries In Mississippi, John Brian Alford

Theses and Dissertations

I used multivariate, hierarchical analyses to examine the relative influence of watershed-, riparian- and channel-scale environmental characteristics on catch per unit effort (CPUE: fish/angler-hour) and species composition of sport fisheries in Mississippi wadeable streams. Partial canonical correspondence analyses indicated that riparian-scale variables (31.1%) explained more variation in sport fish relative abundances compared to watershed-scale (24.4%) and channel-scale variables (18.9%). Largemouth bass M. salmoides and longear sunfish Lepomis megalotis were more abundant in smaller-watershed streams with dense forest cover and greater woody debris, alkalinity and diverse substrates. Spotted bass M. punctulatus and bluegill L. macrochirus were more abundant in larger-watershed streams …

Arthropod And Plant Communities As Indicators Of Land Rehabilitation Effectiveness In A Semi-Arid Shrub-Steppe, Eric T. Gardner

Theses and Dissertations

We describe a case study evaluating the ecological impact of Bromus tectorum L. (cheatgrass) invasion following fire disturbance and the effectiveness of revegetation in improving ecological integrity in a degraded semi-arid shrub steppe system. The effectiveness of rehabilitation efforts was assessed from measurements of arthropod richness, vegetation and arthropod community composition, and ground cover characteristics in three habitats: undisturbed, burned and weed-infested (B. tectorum), and burned and rehabilitated with native and non-native vegetation. Arthropods were collected in each habitat using pitfall traps. Differences in arthropod richness were compared using rarefaction curves. Non-metric multidimensional scaling, and non-parametric multivariate statistical procedures including …

Stink Bugs On Grain Sorghum In Mississippi: Ecological Relationships With Host Plants And Crop Planting Dates And Crop Damage, Mario Ernesto Parada Jaco

Theses and Dissertations

This study was conducted to determine infestation levels of southern green stink bug, Nezara viridula (L.), and green stink bug, Acrosternum hilare (Say), on host plants including corn, cotton, soybean, sorghum, and non-crop vegetation in a multicrop ecosystem. Stink bug infestations responsible for crop damage on vegetative and panicle stages of grain sorghum planted on different dates were also investigated. Both N. viridula and A. hilare appeared to establish a first generation on non-crop grasses surrounding cultivated fields and then moved to soybean or cotton to begin a second generation. These stink bugs did not appear to be attracted to …

Greening American History: Incorporating An Environmental Perspective Into United States Survey Courses, Nelson Paul Rosit

Theses and Dissertations

To paraphrase a well-known historian, there is too little nature in the study of history. Although environmental history is a well established field, nature and the physical environment are still often excluded agents in history pedagogy. The following essay is an effort to remedy this problem. This dissertation has two main objectives. The first is to define and describe environmental history and present a rationale for its inclusion as a major component of survey history courses. The second is to outline ways college teachers can include an environmental perspective in their instructional strategies. It includes three sample lesson plans that …

Ecology Of Wood Frog (Rana Sylvatica) Parasites On The Northern Plains, Eric E. Pulis

Theses and Dissertations

No abstract provided.

The Association Between Adult Self-Reported Asthma & Potential Exposures To Asthma Triggers In Virginia Workplaces: An Ecological Study, Jeanette R. Bowman

Theses and Dissertations

Introduction: Work-related asthma (WRA) is thought to be the most common occupational lung disease in the U.S., but there is no standard case definition of WRA. Most states, including Virginia, do not require WRA diagnoses to be reported to health departments. At present, there is too little epidemiological data on WRA in Virginia to direct public health planning efforts. Objectives: The first objective of this study was to estimate potential exposure to workplace asthma triggers in each of Virginia's 35 health districts. The second objective was to examine associations at the health district level between workplace asthma triggers, other asthma …

The Impact Of Habitat Fragmentation And The Surrounding Landscape On Insect Communities In Prairie Patches, Sarah K. Fischer

Theses and Dissertations

No abstract provided.

Sinking Poor Decision-Making With Best Practices: A Case Study Of Artificial Reef Decision-Making In The Florida Keys, Thomas Wayne Williams

Theses and Dissertations

The natural reefs of the world are experiencing higher use and pressures, resulting in anthropogenic impacts that are deteriorating many coral stands and creating poor water quality. The Florida Keys rely primarily on the reef system that surrounds the archipelago for their socioeconomic health and successful future. The Florida Keys shares the symbiotic relationship of the terrestrial and marine realms with many other states and countries and the experience of higher demand on the resource. Artificial reefs could provide a substitute to the natural reefs for commercial and recreational users. An increased demand for derelict vessels of the U.S. Navy …

Urban Growth And Segregation In The Roanoke, Virginia, Metropolis: The Effects Of Low-Density Development On Low-Income Populations And Racial Minorities, Freed Etienne

Theses and Dissertations

This dissertation examines urban growth patterns in the Roanoke, Virginia, metropolis. It draws on the literature of contemporary human ecology and social area analysis to examine the effects of low-density development on low-income populations and racial minorities. The continuous spread of residential development beyond the boundaries of the central city and older suburbs into more distant, once rural areas is segregating the metropolitan area by race and income. Since the prominence of the so-called "Chicago School" of urban sociology (1913-1940), contemporary urban sociologists have outlined theories and methods to examine how American urban areas have changed and why. This dissertation …

Distribution Of Chemistry And Sexual Fecundity In The Lichenized-Fungi, Xanthoparmelia Cumberlandia And Xanthoparmelia Coloradoensis On Boulder Mountain, Aquarius Plateau, Ut, Heather Bird Jackson

Theses and Dissertations

Three aspects of Xanthoparmelia cumberlandia and Xanthoparmelia coloradoënsis populations found at two elevations are explored: clustering of secondary chemicals and the resulting implications for taxonomic distinctions, the usefulness of thallus size as an indirect measure of sexual fecundity, and the frequency of sexual reproduction.

First, we use clustering of 46 chemicals produced by X. cumberlandia and X. coloradoënsis to evaluate the adequacy of the current taxonomic distinction between them. Using principal components analysis and UPGMA, we find that the currently recognized species boundaries indicated by the presence of stictic acid in X. cumberlandia and salazinic acid in X. coloradoënsis are …

The Impact Of Urbanization On Macroinvertebrate Communities Of Creeks Within Western Georgia, Jeniffer Susan Lang

Theses and Dissertations

Urbanization is a major cause of stream impairment in the United States, altering stream ecological integrity in a variety of ways. While control of point source pollution has largely improved over the last twenty years, the control of non-point source pollution has proved to be more of a challenge. Urbanization in the area surrounding streams has been linked with elevated levels of sediment, heavy metals, organic matter, and nutrients within streams, as well as with other negative effects. Examining the macroinvertebrate communities within streams has proven to be an effective indicator of the effects of urbanization on water quality. This …

Ojibway Women In Transition : The Influence Of The Church On The Traditional Roles Of Objibway Women And Its Effects On Ojibway Society, Anastasia Bowe

Theses and Dissertations

No abstract provided.