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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.
91

Restauration d'une communauté végétale avec potentiel d'accumulation de tourbe sur substrat minéral d'une tourbière perturbée par une route

Guérin, Pascal 19 July 2022 (has links)
La forêt boréale canadienne est fragmentée par plusieurs centaines de milliers de kilomètres de routes. Ces routes sont souvent construites sur des tourbières, un type de milieu humide caractérisé par son accumulation de tourbe, ce qui peut avoir plusieurs impacts sur l'environnement, comme la perturbation de la circulation de l'eau, la perte locale de séquestration du carbone et l'enrichissement en nutriments du site adjacent à la perturbation. Une nouvelle approche de restauration a été testée sur une tourbière affectée par un chemin utilisé dans le cadre de l'extraction des sables bitumineux dans la région de Fort McMurray en Alberta. Cette nouvelle approche consiste en l'extraction partielle du substrat minéral formant la route, l'application de matériel végétal directement sur le substrat minéral résiduel exposé, et la création de canaux souterrains pour favoriser la circulation de l'eau au niveau de la nappe phréatique à travers la route. Le succès de la méthode de restauration a été évalué en fonction de quatre objectifs : 1) rétablir l'homogénéité de la nappe phréatique de part et d'autre de la route; 2) établir de conditions de surface favorables à des communautés végétales typiques des fens; 3) limiter l'impact de la route sur les conditions physico-chimiques de la tourbière entourant la route; et 4) favoriser le retour de communautés végétales typiques des tourbières de la région. Les résultats de cette étude démontrent que la technique de restauration employée permet une meilleure circulation de l'eau et des conditions de surface favorables aux espèces ciblées. Malgré ces améliorations, la route continue à exercer un léger effet de barrage dans les six premiers mètres de la tourbière adjacente. Un effet d'enrichissement en nutriments de la tourbière a été constaté jusqu'à une distance de 2 m d'éloignement de la route. Le succès du rétablissement des communautés végétales n'a pu être confirmé au cours de cette étude se déroulant les deux premières années post-restauration, comme la régénération de communautés ciblées peut prendre plus de trois années. Comme ce projet est l'un des premiers à tester le transfert de la couche muscinale directement sur substrat minéral d'une route, une expérience en serre a également été effectuée afin de déterminer quelles espèces de sphaignes et d'autres mousses sont les mieux adaptées à la colonisation du substrat minéral dans le nord de l'Alberta. Le taux de survie de sept espèces de bryophytes a été évalué sur une période de quatre mois en fonction de la présence ou l'absence d'ombrage. Toutefois, d'autres expériences en serre seront nécessaires pour corroborer ces résultats, et pour étudier un plus grand nombre d'espèces de mousses et ainsi déterminer quels taxons sont plus aptes à coloniser un substrat minéral. Bien que davantage de recherches soient nécessaires, les connaissances acquises lors de cette étude permettront à l'industrie, à des instances gouvernementales et d'autres organismes œuvrant dans les milieux humides à continuer de développer des techniques de restauration prometteuses sur substrat minéral en milieu humide et ainsi promouvoir un développement plus durable en réduisant leur empreinte écologique. / The Canadian boreal forest is fragmented by several hundreds of thousands of kilometers of roads. These roads are often built on peatland, a type of wetland characterized by its accumulation of peat. Roads can have several impacts on the environment, such as the nutrient enrichment of the nearby peatland and the disruption of the water flow. A new reclamation approach was tested on a bog disturbed by a road used for oil sands extraction in the Fort McMurray region, in Alberta. This new approach consists in the partial extraction of the road mineral substrate (in order to rewet the road), the application of the Moss Layer Transfer Technique directly on the residual mineral substrate, and the creation of channels to induce a better water flow at the water table level through the road. The success of the restoration technique is assessed on the basis of four objectives: 1) restoring the homogeneity of the water table on both sides of the road; 2) establishing surface conditions favorable to the target plant communities; 3) mitigating the impact of the road on the physicochemical conditions of the adjacent peatland; 4) restoring plant communities typical of the region's peatlands. The results of this study show that the restoration technique used makes it possible to induce better water flow and surface conditions favorable for the targeted species. However, despite these improvements, the road continues to have a dam effect on the water flow coming from the adjacent peatland. Additionally, an enrichment effect for several chemical elements and components up to a distance of 2 m from the road have been measured in the peatland. As this project is one of the first of its kind to apply the Moss Layer Transfer Technique directly on mineral substrate of a road, a greenhouse experiment was carried out to determine which Sphagnum and other moss species are best suited for the colonization of mineral substrate in northern Alberta. The survival of seven bryophyte species was assessed over a four-month period based on the presence or absence of shading. Further greenhouse experiments will be needed to corroborate these results, to study a greater number of moss species and thus determine which taxa are more apt to colonize a mineral substrate. Although more research is needed, the knowledge acquired during this study will allow industry, government and other organizations working in wetlands to continue to develop promising wetland restoration techniques on mineral substrate and thus promote a more sustainable development by reducing their ecological footprint.
92

Developing an exploration model by investigating the geological controls on reservoir production within the Fort Scott limestone, Ness county, Kansas

Flenthrope, Christopher January 1900 (has links)
Master of Science / Department of Geology / Matthew W. Totten / Ness County, Kansas is situated along the western flank of the Central Kansas uplift, and has been an active center of oil exploration since the 1920’s. It currently ranks fourth among Kansas counties in oil production, largely from Mississippian-age carbonate reservoirs. Some production has been realized from lower Pennsylvanian-age carbonate formations, although the distribution of these reservoirs appears sporadic. The goals of this study were to develop an exploration model that predicts the development of reservoir conditions within the Marmatonage Fort Scott Limestone. A two-township area was studied to examine relationships between production rates and subsurface variations. No core was available through the Fort Scott, hence drill cuttings were thin-sectioned and examined under a petrographic microscope to see details of porosity type not easily visible under a binocular microscope. Production appears to be defined by stratigraphic variations in porosity controlled by original depositional environment. The best wells are within an oolitic limestone, with subsequent development of secondary, vuggy porosity. These conditions occur in bands along the Mississippian paleo-topographic highs. I interpret these bands to be ancient ooid shoals, with geometries and scales analogous to those previously reported from Lansing/Kansas City reservoirs in Russell County, Kansas. This study provides insights into production trends within the Fort Scott Limestone, and should be included during exploration in Ness County, Kansas.
93

Subsurface stratigraphy of the Supai Formation in east central Arizona

Passmore, Virginia Louise, 1942- January 1969 (has links)
No description available.
94

Geologic setting and reservoir characterization of Barnett Formation in southeast Fort Worth Basin, central Texas

Liu, Xufeng 28 October 2014 (has links)
The Mississippian Barnett Formation is a prolific shale-gas reservoir that was deposited in the Fort Worth Basin, Texas. Many previous studies of the Barnett Formation have been conducted in the main production area; few studies have been made of the Barnett Formation in the southern part of the basin, which is a less productive area. In the present research, several cores from the Barnett Formation in Hamilton County, southeast Fort Worth Basin, are studied in detail. Two vertical, continuous cores from Hamilton County, Texas, were studied to delineate the depositional setting, lithofacies, pore types, and reservoir quality of the Barnett Formation in the area. Five lithofacies were defined by analysis of the two cores: (1) laminated clay-rich silty and skeletal peloidal siliceous mudstone; 2) laminated skeletal silty peloidal siliceous mudstone; 3) nonlaminated silty peloidal calcareous mudstone; 4) laminated and nonlaminated skeletal calcareous mudstone; and 5) skeletal phosphatic packstone to grainstone. As indicated from this study, the dominant organic matter type is a mixture of Type II (major) and Type III (minor) kerogen having a mean TOC content of approximately 4%. Analysis of Rock Eval data shows that most of the interval is within the oil window; calculated Ro is approximately 0.9%. Organic geochemistry shows that the hydrocarbon generation potential of the abundant oil-prone kerogen was excellent. Mineralogical analysis reveals that the two types of siliceous mudstone, which are similar in composition to the siliceous mudstone in the main producing area in the northern Fort Worth Basin, are good for hydraulic fracturing and production, but they are also limited by their marginal thickness. Organic matter pores, which are the dominant pore types in these two cores, are consistent with pore types found in currently producing wells in the Newark East Field. This research also suggests that the deposition of Barnett Formation was controlled largely by basinal geometry, suspension settling, and slope-originated gravity-flow events. Skeletal deposits and carbonate-silt starved ripples suggest gravity-flow deposits and bottom-current reworking during deposition. Redox-sensitive elements and degree of pyritization both indicate anoxic/euxinic conditions during the deposition of the Barnett Formation. / text
95

The succesful [i.e. successful] reuse of Fort Harrison / Successful reuse of Fort Harrison

Knable, Daniel January 2000 (has links)
This study provided a broad overview of military base closures and the problems surrounding communities have when redeveloping them. The focus of the study was to analyze the success of the Fort Harrison Transitional Task Force and the Fort Harrison Reuse Authority in their attempt to redevelop Fort Benjamin Harrison, Indiana. The information collected has led me to the conclusion that the base has been successfully redeveloped. The base had a number of fixed geographical and environmental factors that aided in developing a successful plan for redevelopment. The redevelopment plan was comprehensive in nature and followed sound urban planning practices. The plan has been successfully implemented to this point in time. The project will come to completion some time in the next ten years. A final review of the project will have to be done at that time to measure their complete success. / Department of Urban Planning
96

Alcohol and Other Drugs: Attitudes and Use Among Graduate/Professional Students at a Health Science Center

Moorman, Mark Thomas 08 1900 (has links)
Alcohol and other drug use continue to be a major issue on college and university campuses. Few studies have examined alcohol and other drug related issues for a graduate or professional student population. This study examines attitudes, incidents, and consequences of alcohol and other drug use among students enrolled at an academic heath science center. This study incorporated a descriptive research design and utilized the CORE Alcohol and Drug Survey for the collection of data. The data were then analyzed using descriptive statistics and represented in tables as frequencies and percentages. The survey was mailed to all students enrolled in didactic course work at the University of North Texas Health Science Center (UNTHSC) during the fall 2001 semester. This included master's students in physician assistant studies, master's and doctoral students in the biomedical sciences, master's and doctoral students in public health, as well as first and second year medical students. Of the 565 students enrolled in didactic course work, 321 responded to the survey for a return rate of 56.8 %. Statistically significant findings are reported for students at UNTHSC in relation to perceptions of use, actual use, reasons for use, and consequences for use. Similar findings are shown relative to age, gender, marital status, ethnicity, and academic program. Additionally, the UNTHSC students reported statistically significant lower levels of alcohol and drug use, as well as consequences of use than the students represented in the CORE Institutes 2000 national data set. This study identifies the need to investigate alcohol and drug related attitudes, behaviors, and consequences among students studying for professions in health related fields. However, the findings are only relevant to UNTHSC and cannot be generalized to any other population. The study provides personnel at UNTHSC a guide for the development of prevention and intervention programs.
97

From Stockyards to Defense Plants, the Transformation of a City: Fort Worth, Texas, and World War II

Pinkney, Kathryn Currie 12 1900 (has links)
World War II represented a watershed event in the history of the United States and affected political, economic, and social systems at all levels. In particular, the war unleashed forces that caused rapid industrialization, immigration, and urbanization in two regions, the South and the West. This study examines one community's place in that experience as those forces forever altered the city of Fort Worth, Texas. Prior to World War II, Fort Worth's economy revolved around cattle, food-processing, and oil, industries that depended largely on an unskilled labor force. The Fort Worth Stockyards laid claim to the single largest workforce in the city, while manufacturing lagged far behind. After an aggressive campaign waged by city civic and business leaders, Fort Worth acquired a Consolidated Aircraft Corporation assembly plant in early 1941. The presence of that facility initiated an economic transformation that resulted in a major shift away from agriculture and toward manufacturing, particularly the aviation industry. The Consolidated plant sparked industrial development, triggered an influx of newcomers, trained a skilled workforce, and stimulated an economic recovery that lifted the city out of the Depression-era doldrums. When hostilities ended and the United States entered the Cold War period, Consolidated and the adjacent airfield, designated as Carswell Air Force Base in 1948, provided the framework for Fort Worth's postwar industrial expansion and economic prosperity. Fort Worth emerged from World War II as one of the nation's premier aviation production centers and as a linchpin of America's defensive strategy. In the process, it became what historian Roger Lotchin has labeled a "martial metropolis." Ties developed during the war between the city and the military extended into the postwar period and beyond as Fort Worth became part of the growing military/industrial complex. From stockyards to defense plants, World War II transformed Fort Worth from agriculture and mavericks to manufacturing and the military.
98

Projecting Occupational Employment in 1980 in the Dallas and Fort Worth SMSAs

Hughes, Mark R. 12 1900 (has links)
The purpose of the paper is to develop projections of occupational employment in the Dallas and Fort Worth Standard Metropolitan Statistical Areas (SMSA) using Area Projection Method A, developed by the U.S. Bureau of Labor Statistics (BLS) . An objective of the paper is to determine whether reasonable projections can be made for the Dallas and Fort Worth areas using the method. The projections and results can be used by local manpower and education planners to satisfy their planning requirements. The final chapter concludes that Method A does produce reasonable projections, but points out that the projections lack detail. Their value lies in projecting the overall trend and direction of the composition of employment, and their usefulness is primarily in policy making.
99

A Study to Determine the Need for Industrial Arts Activities for Enriching the Elementary Curriculum in the Fort Worth Public Schools

Leeth, James C. 08 1900 (has links)
Industrial arts has been taught in varying degrees in the elementary schools of Texas for a number of years. In some cases, industrial arts activities have been integrated with other subject matter areas, and in some cases they have been taught as a separate subject. There have been several studies made concerning what the nature and extent of industrial arts activities should be at the elementary level. Research indicates, however, that there has been no study made to determine if industrial arts activities could be used to enrich the elementary curriculum in the Fort Worth Independent School District. The problem of this study is to determine if there is a need for industrial arts activities to enrich the elementary curriculum in the Fort Worth Independent School District, Fort Worth, Texas.
100

Assessing the hydrologic impacts of military maneuvers

Pugh, Ginger E. January 1900 (has links)
Master of Science / Department of Biological and Agricultural Engineering / Stacy Hutchinson / Military land management is vital to the future health and usability of maneuver training areas. As land disturbance increases, runoff from the area also increases and may create significant erosion potential. Determining the relationship between what is safe training versus what is harmful to the environment can be done by determining runoff potential at different disturbance percentages given different training intensities. Various studies have shown that soil density, soil structure, plant biodiversity, animal biodiversity, and many other essential ecosystem factors are greatly damaged by continuous training. These ecosystem factors influence runoff amounts and likewise erosion potential in that area. The primary factor examined in this study was the Curve Number (CN). Since military procedures do not have predefined CNs, representative CNs were created based off of CNs for agricultural use and supplemental research about training impacts on the land. Training intensity was broken into four classes: undisturbed, light use, moderate use, and heavy use. Five sample watersheds on Fort Riley were used as replications for the study. Disturbance intensity indexes were broken into 10% increments, and changes in runoff amount and peak rate modeled with TR-55. Statistical analysis was done comparing watersheds, training intensities and disturbance percentages for different storm magnitudes to assess statistically significance of changes in runoff amount and peak rate. This analysis showed that runoff amount and rate were both significantly impacted at every 10% increase on disturbance percentage. Results also showed that at the lower disturbance percentage (less than 30%), runoff amount and rate were not significantly impacted by training use classes. From this it can be seen that even with very little training done to the land increased erosion can be expected.

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