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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Storm Sampling to Assess Inclement Weather Impacts on Water Quality in a Karst Watershed: Sinking Creek, Watauga Watershed, East Tennessee

McCurdy, Porcha 01 May 2020 (has links)
Escherichia coli changes in Sinking Creek, an impaired water body in the Watauga watershed of northeast Tennessee, were assessed during storm events using water samples collected with ISCO automated samplers during eight storms at two locations. Turbidity and electrical conductivity (EC) data loggers were deployed in the creek, and dissolved oxygen (DO) was measured in situ to test the stream’s water quality and reaction to inclement weather. Cotton fabric was deployed at both locations and sent to an external lab to test for the presence of Optical Brighteners (OB), which are indicators of residential wastewater. E. coli and turbidity at the creek generally increased within 2.5 hours of a rain event, remaining above the single sample standard for several hours during the storm. At the spring, E. coli became elevated within 30 minutes of precipitation onset, but generally decreased below the standard during the event.
72

Factors Affecting Emergency Manager, First Responder, and Citizen Disaster Preparedness

Cooks, Tiffany 01 January 2015 (has links)
Despite the increased frequency of natural and man-made disasters, there is a problem in the level of preparedness of emergency managers, responders, and citizens to address them. The purpose of this grounded theory study was to explore the factors that affect these groups' preparedness to inform the development of better emergency plans to handle emergency incidences. The conceptual framework for the study was knowledge management, which was used with a grounded theory approach. The study was guided by primary research questions that focused on understanding psychological, material, temporal, organizational, and other factors that affect the preparedness of emergency managers, first responders, and citizens, and on identifying measures for improving those levels of preparedness. Interview data were collected from a purposeful sample of emergency managers (n = 11), first responders (n = 26), and citizens (n = 26) from South Carolina who had experienced disasters. Secondary data from 6 disasters, 3 emergency operations plans, and 2 standard operating procedure guides were also collected. The constant comparative method was used to analyze data, informing the development of a theory that suggests emergency managers, first responders, and citizens must act collaboratively to prepare for and respond more effectively to disasters, in addition to their independent work. This study promotes positive social change by providing emergency management agencies with information necessary for developing better emergency preparedness plans, thus reducing the personal and economic impact of future disasters.
73

Studies of ecological factors that affect the population and distribution of the western gray squirrel in northcentral Oregon

Foster, Susan Ann 01 January 1992 (has links)
The western gray squirrel (Sciurus griseus griseus Ord) occur only in the Pacific states and in a small corner of extreme western Nevada. Field studies of aspects of the ecology of the most widely distributed subspecies of western gray squirrel (S. griseus) were conducted at three sites in the ponderosa pine-Oregon white oak zone on the eastern slopes of Mt. Hood, Wasco County, Oregon, between 1981 and 1989. From 1981 through 1987, a Hunter Cooperation Program provided remains of squirrels shot during the annual late summer-early autumn hunting season. Other data were gathered through capture and release studies, radiotelemetry, and habitat analysis. The age structure of these populations, as revealed by examination of squirrels killed by hunters, is predominantly mature animals. Also, the population as estimated by hunter success during the Hunter Cooperation Program and by field observations appears to be declining. In the sites studied, western gray squirrels have two seasons of reproductive activity annually. Some individuals mate from January through March; their young emerge from the nest in May and June. Other individuals mate during May and June; their young emerge in August and September. The latter matings are usually the most productive. Analysis of nest trees and their surroundings revealed that nests are most likely to be located in mature trees that have well-developed crowns and occur in stands with a high degree of canopy closure. Nest trees were usually located within approximately 180 meters of permanent water and on sites with a south-southeasterly exposure. Home ranges of squirrels examined in this study were usually large compared to home ranges reported for this species elsewhere in its range. Given the cost of having large home ranges, it seems possible that the squirrels at these study sites exist in less than optimal ecological circumstances. Human factors that may have contributed to the decline of the populations in this study may include the nature of logging activities and the timing of the annual hunting season. Limiting factors other than human activities may include competition with other mast-consuming animals (mule deer, elk, wild turkeys, and three other species of squirrels) for limited and variable mast crops.
74

Geochemical Impacts From Permanganate Oxidation Based on Field Scale Assessments.

Moore, Kelly Ann 13 December 2008 (has links) (PDF)
In situ chemical oxidation (ISCO) using permanganate is a technology for treatment of organic hazardous wastes. This research is a review of 30 permanganate (MnO4-) ISCO sites to determine whether there are long term impacts on groundwater quality due to the introduction of the oxidant into the subsurface. A second objective is to determine if manganese concentration can be predicted by trends in specific pre and postoxidation monitored parameters (i.e., pH and oxidation reduction potential (ORP)). The final objective is to identify the effects of site and design conditions on groundwater conditions postoxidation. Results indicate that (1) there are limited long term groundwater impacts due to oxidant introduction (i.e., water quality indicators begin to approach preoxidation levels by 2 years postoxidation), (2) manganese concentrations can be predicted and (3) site and design conditions have pronounced short term impacts on geochemical parameters (i.e., especially site media type, mass of oxidant injected, and initial ORP).
75

Environmental Justice in the Elizabeth River Watershed: Exploring the Utility of Environmental Justice Screening Tools

Ramirez, Julianna M. 01 January 2022 (has links) (PDF)
The Environmental Justice (EJ) movement has long highlighted the disproportionate exposure to environmental hazards experienced by Black, Indigenous, People of Color (BIPOC) and low-income communities across the country. Environmental practitioners have recently focused on utilizing EJ screening tools, which combine environmental and social data to visualize vulnerable communities, to begin to address environmental injustice rampant in BIPOC and low-income communities. This project explores EJ theoretical frameworks and the historical context of social oppression and environmental pollution in the Elizabeth River watershed (ERW) of Virginia to: 1) understand the social, political, and economic context behind environmental injustice; and 2) generate goals to address environmental injustice with a particular focus on utilizing EJ screening tools. This project highlights five EJ theoretical frameworks that can be used to explain disproportionate exposure to environmental hazards: 1) Racism and Discrimination; 2) Exploitation, Manipulation, Enticement, and Intimidation; 3) Institutional Practices; 4) Economics; and 5) Physical Characteristics and provides an overview of the history of the ERW to highlight the operation of these frameworks. Further, this project suggests three major goals to address environmental injustice: 1) empowering communities through equitable and just community engagement; 2) mapping distributions of environmental hazards, social factors, and institutional practices using EJ screening tools; and 3) ensuring that environmental amenities, burdens, and practices are equitably distributed and target vulnerable communities using EJ screening tools. This project serves as a framework for exploring the social, political, and economic contexts that give rise to environmental injustice and how EJ screening tools can be used to begin addressing them.
76

Three Essays on Racial Disparities in Infant Health and Air Pollution Exposure

Scharber, Helen 01 September 2011 (has links)
This three-essay dissertation examines racial disparities in infant health outcomes and exposure to air pollution in Texas. It also asks whether the EPA's Risk-Screening Environmental Indicators Geographic Microdata (RSEI-GM) might be used to assess the effects of little-studied toxic air pollutants on infant health outcomes. Chapter 1 contributes to the ``weathering'' literature, which has shown that disparities in infant health outcomes between non-Hispanic black and non-Hispanic white women tend to widen with age. In this study, we ask whether the same patterns are observed in Texas and among Hispanic women, since other studies have focused on black and white women from other regions. We find that black and Hispanic women in Texas do ``weather'' earlier than white mothers with respect to rates of low birthweight and preterm birth. This differential weathering appears to be mediated by racial disparities in the distribution and response to socioeconomic risk factors, though a large gap between black and white mothers across all ages remains unexplained. Chapter 2 extends the statistical environmental justice literature by examining the distribution of toxic air pollution across infants in Texas. We find that, within Texas cities, being black or Hispanic is a significant predictor of how much pollution one is exposed to at birth. We further find that, among mothers who move between births, white mothers tend to move to significantly cleaner areas than black or Hispanic mothers. In Chapter 3, we use geocoded birth records matched to square-kilometer pollution concentration estimates from the RSEI-GM to ask whether the pollution-outcome relationships that emerge through regression analysis are similar to the effects found in previous research. If so, the RSEI-GM might be used to study the health effects of nearly 600 chemicals tracked in that dataset. We conclude, based on instability of results across various specifications and lack of correspondence to previous results, that the merged birth record-RSEI data are not appropriate for statistical epidemiology research.
77

The Biological, Physical And Chemical Response Of The Little Creek Watershed To The 2020 CZU Lighting Complex Fire

Fontana, Natalie 01 December 2023 (has links) (PDF)
This post-fire study was conducted to characterize and observe fire induced changes in physical habitat parameters, water-quality conditions and macroinvertebrate assemblages in the Little Creek watershed, a tributary to Scotts Creek located in Cal Poly’s Swanton Pacific Ranch in Davenport, California. Pre-fire data was collected by a Cal Poly student, John Hardy, for his 2017 thesis. Post-burn bioassessment surveys for this study were repeated at four of the same study sites used by Hardy to provide comparisons to the California Stream Condition Index via a modified version of the State of California’s Surface Water Ambient Monitoring Program protocol. Macroinvertebrates were taxonomically identified to the family level. Commonly used bioassessment indices were utilized in conjunction with Stepwise regression and Analysis of Variance on both pre- and post-fire datasets to illustrate how physical habitat and water quality parameters changed after the fire and to determine the significance of collected environmental variables (stream shading, cross sectional area, and median particle size) as predictors of macroinvertebrate community structure. Despite most of Little Creek having moderate and high burn severities, it was found that physical habitat, water quality and benthic macroinvertebrate populations were not greatly disturbed by the 2020 CZU lighting complex fire. Proportions of highly disturbance/pollution sensitive taxa and increased following the wildfire and there was a dramatic shift from collector-gatherer to predator organisms. Comparison of pre- and post-fire data in this study showed fire having a minimal effect on the studied watershed. Difference in study goals and associated protocols used in the pre- and post-fire studies and the low water year following the wildfire, complicates statistical comparisons and poses threat to the validity of results. However, there is opportunity for further investigation about the ability of an ecosystem to successfully recover from natural disasters and disturbances, specifically when there is little human impact (or influence) on the ecosystem.
78

Paukščių populiacijų gausos indekso naudojimas bioindikacijai Europos Sąjungoje / Use of bird population indices as biological indicators in the European Union

Platovienė, Teresa 29 June 2009 (has links)
Paukščiai laikomi gerais biologinės įvairovės ir aplinkos kokybės indikatoriais. Kasmetinės paukščių apskaitos vykdomos visose ES šalyse ir kai kuriuose kitose Europos valstybėse. Paukščių populiacijų gausos indeksai apjungia informaciją apie atrinktų paukščių rūšių populiacijų bendrus gausos pokyčius. Paukščių rūšys parenkamos atsižvelgiant į šalies paukščių rūšinę sudėtį. Europoje plačiausiai naudojami įprastų rūšių paukščių indeksai, kurie yra paremti paukščių populiacijų gausos pokyčių tendencijų vidurkio skaičiavimu. Jungtinės Karalystės ir Nyderlandų mokslininkai pirmauja skaičiuojant ir naudojant paukščių populiacijų indeksą biologinei inikacijai vertinti. Plačiai paplitusių ir įprastų miško paukščių populiacijų tendencijos rodo – kad jie visoje Europoje nežymiai nyksta. Agrarinio kraštovaizdžio paukščių populiacijų indeksai atskleidžia, kad Vakarų Europoje paukščių populiacijų sumažėja per pastaruosius 25 m. apie 40 proc., miškingo kraštovaizdžio- apie 20 proc., o dažnų paikščių populiacijų gausa beveik nepakyto. Surinkta po įvairius šaltinius išsibarščiusi informacija rodo, kad svarbiausia paukščių nykimo priežastis yra nepakankamai palanki žemės ir miškų ūkio politika. / Birds are considered as good biodiversity and environment quality indicators. Annual bird surveys are being performed in all European Union and in some other European countries. Bird population indices integrate information on changes of numbers of populations of selected species. National lists of the species to be used when calculating bird population indices are formed depending on country specific bird fauna. In Europe common bird indices are used most widely. They are based on calculation of average changes of local population numbers. Scientists of United Kingdom and the Netherlands are leading methodological studies when calculating bird population index with the goal of biological indication. Trends of the common forest bird populations show their insignificant decrease in all the Europe. During recent 25 years in West Europe indices of bird populations of high specialised species discover their big decrease (about 40 %) in agricultural landscape and reasonable decrease (about 20 %) in forest landscape. Meanwhile populations of very common non-specialised species have remained near stabile. Collected rather scare and dispersed scientific literature shows that not enough environmentally friendly agriculture and forestry have to be considered as a main reason of bird population decline in Europe.
79

San Diego’s Options for Alternate Sources of Water: A comparative analysis of water recycling and desalination as alternative methods to importing water

Pokorny, Alana O 01 January 2015 (has links)
This paper describes the processes, methods, backgrounds, and economic challenges, of Desalination and Water Recycling and provide current examples of both. To create a baseline with which to compare the two methods, I will also delve into the history of California water policy. This complicated past is the reason water importation into Southern California remains the main method of obtaining water. Yet, as the current drought continues and technology advances, the need for imported water will become obsolete as the methods for recycling and desalinating water become less expensive, more convenient and more equitable. In the conclusion, all the methods will be compared and I will give suggestions on potential solutions for solving San Diego’s water dependence.
80

"Mining" for a Reference Condition in Southern West Virginia Streams

Rouch, Matthew 01 January 2014 (has links)
Quarterly samples were used to estimate assemblage-level (all species combined) fish production within three minimally-impacted, southern West Virginia streams. The total annual fish production estimate was highest in Slaunch Fork (37.52 kg∙ha-1∙y-1), a tributary of the Tug Fork River, and lowest in Cabin Creek (10.59 kg∙ha-1∙y-1), a Guyandotte River tributary. Creek Chub Semotilus atromaculatus, Mottled Sculpin Cottus bairdii and Blacknose Dace Rhinicthys atratulus were the most abundant species among sites, accounting for >90% of all sampled individuals. Reference condition criteria were also selected and metrics calculated for each of the three stream sites using a variety of established metrics. According to established criteria, all three of our sites scored high enough to be listed as “reference” sites. Third, a comprehensive GIS analysis was conducted in order to determine land use patterns and predict where similar assemblages would be present using various climatological and physical characteristics of our stream sites. These analyses revealed rapid expansion of surface mining activities putting many stream systems at risk.

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