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The Effects Of Regulatory Uncertainty On The U.S. Acid Rain Program, Narendra Paramanand

LSU Master's Theses

Title IV of the Clean Air Act Amendments of 1990 (CAAA 1990) created the first large scale cap-and-trade program as a means to control acid rain in the United States. The program regulated the emission of sulfur dioxide (SO2) and nitrous oxide (NOx) in the atmosphere—the precursor to acid rain (formerly acid deposition). Economists have long argued for the use of market-based incentive approach as oppose to the traditional command-and-control methods for its ability to be efficient and cost-effective. Title IV went into full effect in 1995 and has been lauded among one of the most successful regulation as it …

Movements And Habitat Use Of Southeastern Blue Sucker Cycleptus Merdionalis In The Lower Pearl River, Devon Charles Oliver

LSU Master's Theses

Riverine fisheries management programs often do not focus on non-sport and non-commercial fishes, such as catostomids, yet many suckers have become threatened or endangered throughout river systems in the United States because of habitat alterations. In the Pearl River, sedimentation, dam construction, and other hydrologic modifications have negatively impacted habitats used by southeastern blue suckers Cycleptus meridionalis, a species of concern in both Louisiana and Mississippi. The principal objective of this project was to investigate habitat use of likely historically abundant southeastern blue suckers in the lower Pearl River. During electrofishing surveys in 2010 and 2011, we observed no southeastern …

Composition And Physiological Characteristics Of The University Lake Ecosystem Phytoplankton Community: Impacts Of Seasonal And Episodic Events, Brianne Elizabeth Norris

LSU Master's Theses

This research determined the changes in phytoplankton community composition in a shallow subtropical lake, influenced by urban surroundings. Specifically this research focused on the effects of seasonal progression and episodic events on the changing inorganic nutrient dynamics and the effects those dynamics had on the phytoplankton community composition and productivity. This research quantified gross primary production and respiration to determine if seasonality or episodic events were acting as forcing functions of the phytoplankton community composition. Water samples were collected weekly at three sites on the lake’s perimeter, as well as following episodic events, to monitor nitrate (NO3), phosphate (PO4-3), ammonium …

Minchin Studies, Teaches Conservation Issues, Aldemaro Romero Jr.

Publications and Research

No abstract provided.

Jennings Studies Environmental Pollutants, Aldemaro Romero Jr.

Publications and Research

No abstract provided.

Changing Land Use On Unproductive Soils, Andrew Blake, Mike Clarke, Angela Stuart-Street

Resource management technical reports

A three year study completed in 2010 examined farming systems in the north-eastern agricultural region and eastern wheatbelt of Western Australia which experienced a succession of variable seasons from 2000. This culminated in severe drought in 2006 and 2007. At that time, farmers experienced labour shortages and declining terms of trade triggered by cost inflation outpacing growth in commodity prices. As a result, farm business equity was eroded as farm debt escalated. This left many farm businesses in a highly vulnerable state. At the time of the study many farmers were facing an uncertain future.

These experiences, coupled with a …

Stochastic Models For Evolutionary Genetic Problems, Wei Liao

Electronic Theses and Dissertations

Two stochastic models are designed for answering evolutionary genetic problems. The first study shows that inbreeding-environment interactions increase extinction risk. The second research demonstrates that 1) the carrying capacity and initial population growth rate is critical to determine the population persistence time; 2) increasing the advantageous mutation rate reduces the extinction risk although its effects are usually shadoby population size and fitness; 3) the new mutation correlation among environments rises during the evolution process, but it has compromised effects on population fate. Being able to accurately estimate the persistence time of populations of endangered plants and animals is central to …

The Effects Of Climate On The Growth Of Winter Wheat And Spring Barley In An Irish Context, Adrian Kennedy

Theses

The climate of earth is always changing due to natural events, however it is thought that the rapid warming period currently taking place is primarily due human activity to (environmental protection agency 2012). Climate change is altering the environment and this will have consequences for agriculture (Teagasc publications 2012). In this study we examine the relationship between weather and the yield of winter wheat and spring barley in an Irish context using data gathered from 2004-2010 at the Teagasc Oak Park research centre in Carlow. The data was analysed using a mixed effect model to test which if any weather …

Identifying Risk Factors For Disparities In Breast Cancer Mortality Among African-American And Hispanic Women, Nancy Tian, Pierre Goovaerts, F. Benjamin Zhan, T. Edwin Chow, Jeff Gaines Wilson

School of Earth, Environmental, & Marine Sciences Faculty Publications

Background: This study evaluated the risk factors associated with racial disparities in female breast cancer mortality for African-American and Hispanic women at the census tract level in Texas from 1995 to 2005.

Methods: Data on female breast cancer cases were obtained from the Texas Cancer Registry. Socioeconomic and demographic data were collected from Census 2000. Network distance and driving times to mammography facilities were estimated using Geographic Information System techniques. Demographic, poverty and spatial accessibility factors were constructed using principal component analysis. Logistic regression models were developed to predict the census tracts with significant racial disparities in breast cancer mortality …

Effects Of Hypoxia Exposure On Hepatic Cytochrome P450 1a (Cyp1a) Expression In Atlantic Croaker: Molecular Mechanisms Of Cyp1a Down-Regulation, Md. Saydur Rahman, Peter Thomas

School of Earth, Environmental, & Marine Sciences Faculty Publications

Hypoxia-inducible factor-α (HIF-α) and cytochrome P450 1A (CYP1A) are biomarkers of environmental exposure to hypoxia and organic xenobiotic chemicals that act through the aryl hydrocarbon receptor, respectively. Many aquatic environments heavily contaminated with organic chemicals, such as harbors, are also hypoxic. Recently, we and other scientists reported HIF-α genes are upregulated by hypoxia exposure in aquatic organisms, but the molecular mechanisms of hypoxia regulation of CYP1A expression have not been investigated in teleost fishes. As a first step in understanding the molecular mechanisms of hypoxia modulation of CYP1A expression in fish, we characterized CYP1A cDNA from croaker liver. Hypoxia exposure …

The Vascular Flora Of Breaks Interstate Park, Pike County, Kentucky, And Dickenson County, Virginia, Julie Bennett Clark

Online Theses and Dissertations

The vascular flora of Breaks Interstate Park was documented during two growing seasons, 2008 and 2009; with supplemental collections made in 2010 and 2011. The project area is located in eastern Kentucky and western Virginia at the northeastern terminus of Pine Mountain along the Appalachian Plateau. A total of 118 families, 341 genera, and 549 species, varieties, and subspecies were documented from Breaks Interstate Park. Six main vegetative communities were described: mesophytic forest, upper slopes and ridgetops, ponds/wetlands, river bottomland and floodplain/streamside, sandstone outcrops, and disturbed/open areas. Eleven rare species with state rankings were identified: Adlumia fungosa, Hydrastis canadensis, Juglans …

Cometabolic Degradation Of Halogenated Aliphatic Hydrocarbons By Aerobic Microorganisms Naturally Associated With Wetland Plant Roots, Madelyn M. Smith

Browse all Theses and Dissertations

Wetland systems provide both anaerobic (reducing) and aerobic (oxidizing) zones for the biodegradation of chlorinated aliphatic hydrocarbons (CAH). In particular, wetland plant roots provide micro-oxidizing environments for methanotrophic bacteria from the presence of methane, which is produced in anaerobic zones, and oxygen, which is brought to the subsurface by roots of wetland plants; this shows the potential for cometabolic degradation of common organic pollutants.

This study explored the natural attenuation of CAHs by methanotrophic bacteria naturally associated with roots of the common wetland plant, Carex comosa. Root microcosms were amended with varying concentrations of methane; trichloroethene; cis 1,2-dichloroethene; 1,2-dichloroethane; or …

Why Is There Such A High Concentration Of Vertebrate Remains Within A Bone-Bed Along Clapp Creek, Williamsburg County, South Carolina?, Jennifer R. Soehner

Browse all Theses and Dissertations

A phosphatic bone-bed occurs along Clapp Creek in Kingstree, South Carolina, within the east-central portion of the coastal plain. The location of the research site is within the Chicora Member of the Williamsburg Formation. The paleoenvironment of this site was most likely a complex estuary with microenvironments that included tidal channels, tidal deltas, tidal flats, marshes and subtidal bays. The high diversity and large time span in the bone-bed is explained by the transgressive environment and storm deposits. The phosphate content of the bone-bed is from the calcium phosphate occurring in the coprolites of carnivores and the higher concentration of …

Central Arctic Lithostratigraphy: Implication For Sediment Transport And Paleoceanography, Edward Augustus Council Iii

Browse all Theses and Dissertations

Multiple cores from the Arctic were analyzed by XRF methods to determine the western Arctic lithostratigraphy as expressed in its geochemistry. In general, glacial and interglacial events have distinctly different chemistry. During glacial events, the sediments have elevated Ti, Fe, Rb, and Zr concentrations and depressed Sr and Mn concentrations. The opposite is true of the brown layers, where Ti, Fe, Rb and Zr are lower with higher levels of Mn and Sr. These data indicate that there are 18 chemically unique lithologic units (LUs) that exist among MIS-1 to MIS-16 age sediments. Isopach maps indicate two general depositional patterns …

Among-Locus Heterogeneity In Genetic Diversity And Divergence In Two Pairs Of Duck Species (Genus: Anas), Kirandeep K. Dhami

Browse all Theses and Dissertations

Genetic diversity and divergence at a locus are the result of interactions among the fundamental evolutionary forces of mutation, genetic drift, gene flow and natural selection. Variation in the strength of these forces can cause high heterogeneity in diversity and divergence across the genome. The overall objective of this thesis was to examine the role of population history vs. selection in generating heterogeneity in genetic diversity and differentiation. In Chapter 1, I examine the role of dispersal behavior in causing genetic differentiation and population structure within and between two morphologically distinct Australian duck species that differ in ecology and life …

Assessing The Drivers Of Adaptive Radiation In A Complex Of Gall Midges: A Multitrophic Perspective On Ecological Speciation, Jeremy J. Heath

Browse all Theses and Dissertations

Natural enemies as selective forces maintaining and shaping morphological, physiological, and behavioral divergence in adaptive radiations have received very little attention. Until recently, the focus has been on primary resource competition as a major driver of trait divergence in adaptive radiations. Here I consider the role of natural enemies specifically in driving trait divergence in a complex of gall midges in the nominal species Asteromyia carbonifera (Diptera: Cecidomyiidae), which appears to be in the throes of an incipient adaptive radiation on its host plant, goldenrod (Solidago). This galler uses a symbiotic fungus (Botryosphaeria dothidae) as a …

Degradation Of Chlorinated Hydrocarbons In Groundwater Passing Through The Treatment Wetland At Wright-Patterson Air Force Base: Analysis Of Results Collected During 2001-'06, Annamarie F. Therrien

Browse all Theses and Dissertations

Constructed wetlands are an efficient and cost effective means for chlorinated aliphatic hydrocarbon remediation, and will therefore continue to gain momentum as an accepted treatment by the US EPA (U.S. EPA, 1995; Amarante, 2000; Lien, 2001; WETPOL, 2009). The treatment options for chlorinated aliphatic hydrocarbons (CAHs), including wetlands, capitalize on aerobic/anaerobic interfaces in which bacterially mediated reduction-oxidation reactions degrade pollutants (Li, 1997; Bradley, 1998; Lorah and Voytek, 2004; Amon, 2007; Imfeld, 2008). In August 2000, researchers at Wright State University (WSU) combined efforts with the United States Air Force Institute of Technology (AFIT) to construct a pilot-scale upward-flow treatment wetland …

Factors Controlling Nickel Bioavailability And Effects On Benthic Invertebrates In Hardwater Freshwater Streams, Kevin Wayne Custer

Browse all Theses and Dissertations

Sediments in aquatic ecosystems function ecologically as habitat, food, and refugia that aid in reproduction processes, and chemically as sources and sinks for contaminants. Sediment contamination from metals and organics has been linked to numerous health and ecological effects, extending from fish consumption advisories to endangered species listings. This dissertation research examines Ni bioavailability (simultaneously extracted metal (SEM)/acid volatile sulfide (AVS) models) and toxicity in five separate studies using Ni-spiked sediments in a variety of designs, and mainly with two different sediment types (low AVS, total organic carbon (TOC), and high AVS, TOC).

Two separate streamside mesocosm Ni experiments indicated …

Do Bioclimate Variables Improve Performance Of Climate Envelope Models?, James I. Watling, Stephanie S. Romanach, David N. Bucklin, Carolina Speroterra, Laura A. Brandt, Leonard G. Pearlstine, Frank J. Mazzotti

United States Geological Survey: Staff Publications

Climate envelope models are widely used to forecast potential effects of climate change on species distributions. A key issue in climate envelope modeling is the selection of predictor variables that most directly influence species. To determine whether model performance and spatial predictions were related to the selection of predictor variables, we compared models using bioclimate variables with models constructed from monthly climate data for twelve terrestrial vertebrate species in the southeastern USA using two different algorithms (random forests or generalized linear models), and two model selection techniques (using uncorrelated predictors or a subset of user-defined biologically relevant predictor variables). There …

Differences In Immune Defense Evasion Of Selected Inbred Lines Of Heterorhabditis Bacteriophora In Two White Grub Species, Ruisheng An, Marcio Voss, Ganpati B. Jagdale, Parwinder Grewal

School of Earth, Environmental, & Marine Sciences Faculty Publications

We determined virulence of seven Heterorhabditis bacteriophora strain GPS11 inbred lines possessing superior infective juvenile longevity, and heat and ultra violet radiation tolerance against white grubs Popillia japonica and Cyclocephala borealis. At 1 and 2 weeks after treatment, inbred line A2 was significantly more virulent towards P. japonica compared to the parent strain GPS11 and inbred lines A7, A8, A12 and A21; and line A2 caused significantly higher C. borealis mortality than lines A6 and A12. Penetration, encapsulation and survival of two inbred lines, A2 and A12, that showed the highest and lowest virulence against both grub species were then …

Method Development For Detecting And Characterizing Manufactured Silver Nanoparticles In Soil Pore Water Using Asymmetrical Flow Field-Flow Fractionation, Annie R. Whitley

Theses and Dissertations--Plant and Soil Sciences

Recent advances in nanotechnology have led to the production of materials with nanoscale dimensions (nm) and properties distinctly different from their bulk (>100 nm) counterparts. With increased use, it is inevitable that nanomaterials will accumulate in the environment and there is concern that the novel properties of nanomaterials could result in detrimental environmental and human health effects. In particular, there has been concern recently regarding the use of silver (Ag) based nanomaterials as antimicrobial agents in consumer and medical products. Current regulations dealing with the discharge of metals into the environment are based on total concentrations with no consideration …

An Environmental Systems Analysis Of Hydropower And Its Effects Upon Indigenous Settlements In Karnataka, India, Amy Joens

Honors Program Theses

Hydroelectricity is a very common method of energy production. Large dams are constantly being introduced to the river landscape in areas all over the world. There are definite benefits to hydropower, but the drawbacks may be even more evident. As modernization and development expand across developing nations like India, indigenous populations are often subject to the highest ration of negative impacts and consequences. This research explores both the costs and benefits of hydroelectricity, while using specific examples of dam construction projects to analyze aspects of the cumulative effects of a hydropower project. The Kabini Dam in southern Karnataka, India is …

Would Predatory Drillhole Frequency On Chione Spp. Increase Under The Suggested Climate Change Scenario? Comparing Pleistocene And Modern Rhodolith Beds, Carlos E. Cintra-Buenrostro

School of Earth, Environmental, & Marine Sciences Faculty Publications

The analysis of predatory drillholes allow paleontologists to reconstruct trophic relationships of ancient systems. To evaluate the potential effects of climate and sea level change on predation frequency by gastropods on bivalves, species of the genus Chione from the Gulf of California were selected because they are a commercially exploited resource - at least locally - and abundant in both modern and Pleistocene (sea level high stand of oxygen substage 5e) samples from rhodolith beds. The present study focused to answer a practical question: would predation on Chione spp. increase under the suggested climate - warming - change scenario? A …

Extensive Reproductive Disruption, Ovarian Masculinization And Aromatase Suppression In Atlantic Croaker In The Northern Gulf Of Mexico Hypoxic Zone, Peter Thomas, Md. Saydur Rahman

School of Earth, Environmental, & Marine Sciences Faculty Publications

The long-term impacts on marine ecosystems of the recent dramatic worldwide increase in the incidence of coastal hypoxia are unknown. Here, we show widespread reproductive disruption in Atlantic croakers collected from hypoxic sites approximately 120 km apart in the extensive northern Gulf of Mexico continental shelf hypoxic zone. Gonadal growth and gamete production were impaired in croakers from hypoxic sites compared with fish from reference normoxic sites east of the Mississippi River Delta. Male germ cells were detected in approximately 19 per cent of croaker ovaries collected in the hypoxic region, but were absent in ovaries from normoxic sites. In …

Using Participatory Scenarios To Stimulate Social Learning For Collaborative Sustainable Development, Kris A. Johnson, Genya Dana, Nicholas R. Jordan, Kathy J. Draeger, Anne Kapuscinski

Dartmouth Scholarship

Interdependent human and biophysical systems are highly complex and behave in unpredictable and uncontrollable ways. Social and ecological challenges that emerge from this complexity often defy straightforward solutions, and efforts to address these problems will require not only scientific and technological capabilities but also learning and adaptation. Scenarios are a useful tool for grappling with the uncertainty and complexity of social-ecological challenges because they enable participants to build adaptive capacity through the contemplation of multiple future possibilities. Furthermore, scenarios provide a platform for social learning, which is critical to acting in the face of uncertain, complex, and conflict-laden problems. We …

Integrated Assessment Of Anthropogenic, Climate, And Policy Induced Changes Of Phosphorus Export In The United States Laurentian Great Lakes Watersheds, Meredith Ballard Labeau

Dissertations, Master's Theses and Master's Reports - Open

Anthropogenic activities have increased phosphorus (P) loading in tributaries to the Laurentian Great Lakes resulting in eutrophication in small bays to most notably, Lake Erie. Changes to surface water quality from P loading have resulted in billions of dollars in damage and threaten the health of the world’s largest freshwater resource. To understand the factors affecting P delivery with projected increasing urban lands and biofuels expansion, two spatially explicit models were coupled. The coupled models predict that the majority of the basin will experience a significant increase in urban area P sources while the agriculture intensity and forest sources of …

Analysis Of A Wound-Induced Gene Family In Glycine Max, Gena Robertson

Masters Theses

Gene families in plants are important in understanding genome evolution indicating when and where genome duplications and segmental duplications occurred as well as subsequent divergence and subfunctionalization. A gene family in Glycine max that encodes a WI12 protein, wound-induced protein, was found to consist of ten genes on five chromosomes. Wound-induced proteins are activated in response to wounding in plants, and the WI12 protein in particular is thought to be involved in cell wall modifications at the wound site. A variety of bioinformatics tools have been used to analyze the expansion of this family in soybean as well as identify …

Challenging The “Man” In Mangroves: The Missing Role Of Women In Mangrove Conservation, Alyssa L. Bosold

Student Publications

Mangroves provide valuable ecosystem services including carbon sequestration, pollution filtration, and protection from tsunamis, tropical storms, and coastal erosion. They also supply coastal communities with important natural resources like firewood, medicine, timber, honey, and fodder for livestock. Unfortunately, the world’s mangroves are rapidly degrading due to rising coastal population, climate change, and destruction for coastal development, agriculture, and aquaculture. Considering their value for the environment and coastal communities, mangrove conservation should become a priority and effort must be invested to find new and successful methods for conserving mangrove ecosystems. As it has proven effective in other conservation contexts, a gendered …

Recent Changes In The Growth And Nutrient Limitation Of Benthic And Pelagic Algae In Arctic Tundra Ponds, Christina Hernandez

Open Access Theses & Dissertations

Arctic ponds are a dominant feature in Barrow, Alaska. Ponds may function as carbon sinks during the growing season from production of photosynthetic organisms like algae; however, little work has been done on this topic. Environmental changes have been occurring in the Arctic stemming from climate change and human perturbations. The focus of this study was to assess a historically studied region for changes in algal primary production that may have been produced due to increases in temperature over the past 40 years and increased human development. Additionally, this study aimed to determine nutrient limitation of algal production in the …

Sustainable Riparian Restoration - The Utilization Of Sewage Effluent To Construct Wetlands Along The Rio Grande: A String Of Pearls Approach To Replenishment, Michael Earl Landis

Open Access Theses & Dissertations

The Rio Grande, from Elephant Butte Dam to El Paso, has been transformed from a free-flowing wild river into a highly engineered irrigation system. The Rio Grande Project, authorized by Congress in 1905, mandated the Bureau of Reclamation to store and deliver water exclusively to farmers. The river, maintained by the International Boundary and Water Commission, has been straightened and channelized between levees. The laws and policies governing the use of the waters of the Rio Grande are prohibitive to ecological restoration. Prior Appropriation doctrine allows for the exclusive use of these waters.

One sustainable tactic for replenishing the denuded …