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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.
281

Effects of Urbanization on the Quantity and Quality of Storm Water Runoff Recharging Through Caves into the Edwards Aquifer, Bexar County, Texas

Veni, George 01 July 1985 (has links)
Eighty-nine caves and sinkholes were investigated in the Edwards Aquifer recharge zone in Bexar County, Texas. The study examined their hydrogeologic and topographic origins and distribution, relationships to major fracture traces, quantity of recharge into the aquifer and degree of sensitivity towards degradation of the aquifer’s water quality. Groundwater traces were attempted to determine aquifer flow routes, time of groundwater travel, groundwater volume within conduits, and the aquifer’s capacity for dilution and dispersion of recharged contaminants. Trends in water quality were examined to quantify the volume and variety of contaminants recharged into the aquifer and to determine the effects of urbanization upon the Edwards Aquifer. The Edwards recharge zone was hydrogeologically assessed to rate the sensitivity of its areas. Socio-political impacts on recharge zone development were also examined. Based on the results of the above outlined research method, the conclusions of this investigation are that caves and sinkholes contribute substantial recharge into the Edwards Aquifer, rapidly transmit that recharge to the aquifer and are sensitive sites for potential contamination. The entire recharge zone was determined to be very sensitive to contamination. No significant differences were found between areas within the recharge zone to scale their degree of sensitivity. Major conduit flow networks were found to exist within the aquifer and their groundwater flow paths could be traced. Urban development of the Edwards recharge zone was shown to decrease the volume of recharge and degrade the aquifer’s water quality. No significant detrimental effects on the aquifer were observed. The volume of diminished recharge and the concentration of recharged contaminants that were necessary to produce significant adverse effects on the aquifer were not determined due to lack of precipitation during the study period and inconclusive groundwater tracings. It was recommended that further development of the recharge zone be suspended until the effects of urbanization are quantified.
282

Mechanisms Responsible for Sinkhole Flooding on an Urbanized Karst Terrain: South Sunrise / Media Drive, Bowling Green, Kentucky

Feeney, Thomas 01 December 1986 (has links)
Sinkhole flooding on the urban karst area of Bowling Green, Kentucky, was studied by investigating past flood events in the South Sunrise/Media Drive Sinkhole. The actual flood levels of four floods were compared to levels calculated by an empirical runoff determination method. Outflow capacity tests and dye tracing revealed the nature of drainage within the karst depression. The Soil Conservation Service runoff determination method and the three-hour maximum rainfall event were used to estimate the level of flooding. Three of the four flood events studied provided deviations between the actual and calculated flood levels of less than 0.26 feet (0.08 meters). The fourth event produced a deviation of 1.45 feet (0.44 meters) which was explained by the intense nature of the precipitation event. Analysis of the data resulted in the conclusion that surface storm water runoff exceeded the outflow capacity of the sinkhole drains during all four flood events and that the peak flood elevations were not related to the level of the water table in the area. Evidence also suggested that drainage from the base of the South Sunrise/Media Drive Sinkhole occurs through interconnecting voids associated with a cave roof breakdown pile, and not through an efficient system of solution conduits.
283

Les bâtiments du monde viti- vinicole en Languedoc-Roussillon des années 1860 à nos jours : étude d'une infrastructure privée et communautaire / Non communiqué

Ganibenc, Dominique 14 December 2012 (has links)
Cette étude porte sur les différentes constructions du monde vitivinicole en Languedoc-Roussillon, des années 1860 à nos jours. Elle a pour objectif l’étude de leur place et impact dans le paysage languedocien. Une partie de la recherche porte sur les constructions privées, qu’elles soient d’habitation ou d’exploitation. L’analyse des bâtiments coopératifsvinicoles se veut plus exhaustive : elle est tournée vers les caves et les distilleries. La réalisation d’un corpus de ces structures, qu’elles soient privées ou communautaires, a permis d’en analyser l’évolution typologique et architecturale. La réflexion s’axe principalement sur les nécessités de la création d’un réseau coopératif vinicole, les formes et conditions de son développement ainsi que sur la mise en place des organismes de tutelle. Sa répartition, territoriale comme chronologique, a été analysée à l’échelle d’une région, avec les caves coopératives de la Gironde comme point de comparaison. Les principaux maîtres d’oeuvre des réseaux ont également été répertoriés, leurs oeuvres énumérées et leur vocabulaire architectural, étudié. Enfin, l’analyse typologique et architecturale de ces bâtiments du monde vitivinicole, tant privés que communautaires, ainsi que leur actualité en prise avec une restructuration sévère du réseau coopératif, amène à se questionner sur leur valeur historique et symbolique. Il s’agit donc désormais d’évaluer les moyens d’insérer ce riche héritage viticole dans le patrimoine régional, d’en assurer la protection et la mise en valeur. / This study concerns the different constructions used in the making of wine in Languedoc-Roussillon from the 1860s to the present day. It aims at studying their place and impact in ‘Languedocian’ landscape. Part of the research focuses on private buildings, whether residential or commercial. The analysis of cooperative winery buildings is more exhaustive and oriented towards wine cellars and distilleries. The implementation of a corpus of these private or community structures has been done in order to present the evolution and architectural typology. The study is centered mainly on the necessities of creating a wine cooperative network, forms and conditions of its development as well as the establishment of regulatory bodies.Distribution through the period was analyzed across an area with cooperatives of the Gironde as a point of comparison. The main contractor networks have also been identified, and their works listed and there has also been a focus on architectural vocabulary. Finally, a cluster analysis and the architecture of these buildings connected to the wine industry, both private and community, as well as their current engagement with a severe restructuring of the cooperative network, raises the question of their historical and symbolic value. It is time to assess how to ensure this rich viticultural heritage in the region's history is preserved and indeed enhanced.
284

Radon Contamination of Residences in a City Built Upon a Karst Landscape Bowling Green, Warren County, Kentucky

Webster, James William 01 December 1990 (has links)
The United States Environmental Protection Agency (EPA) estimates that 8 to 12% of U.S. homes have radon concentrations that equal or exceed 4 picocuries per liter (pCi/l). A statewide screening of Kentucky by EPA resulted in an average residential radon concentration of 2.8 pCi/l with 17% of the homes at or above 4 pCi/l. EPA requires routine monitoring and maintenance or worker health records in mines and caves having radon daughter concentrations at or above 0.30 working levels (WL). Bowling Green is a city located in a karst region of south central Kentucky. Residents of Bowling Green have been subjected to various environmental hazards that are closely linked with the landscape. Of particular concern has been the recurring problem of chemical fumes rising from contaminated caves and collecting in buildings. The author has recorded radon daughter concentrations in excess of 5 WLs in caves beneath Bowling Green. A preliminary screening of residential radon concentrations in Bowling Green resulted in an average concentration of 25.8 pCi/l. Two of the test results were above 100 pCi/l and were recorded in homes that were known to have a history of fume problems. These results spurred this thesis which addresses the magnitude of residential radon contamination in Bowling Green and its association with the karst landscape. The investigation involved radon daughter testing in Bowling Green caves and residential radon testing. A total of 84 measurements were conducted in order to establish a working average residential radon concentration for the city. Twelve other tests were performed in buildings known to have a history of chemical fume problems. The resulting average residential radon concentration was 9.06 pCi/l. First floor measurements averaged 4.73 pCi/l, and basement measurements averaged 22.92 pCi/l. The overall average for buildings with a history of fume problems was 35.15 pCi/l with first floors and basements averaging 29.75 and 57.40 pCi/l respectively. Forty-six percent of the homes comprising the sample population equaled or exceeded 4 pCi/l. The results of the investigation indicate that: Bowling Green Caves sometime have radon daughter concentrations far in excess of 0.30 WL. The average residential radon concentration for Bowling Green exceeds the average for Kentucky obtained by EPA. The percentage of houses that have radon concentrations at or above 4 pCi/l for the study area exceeds the estimated national average of 8 to 12% and the statewide average. The author suggests that insufficient data was collected to determine whether radon concentrations in Bowling Green homes with a history of chemical fume problems are higher than for the city as a whole.
285

Fossil lizards (squamata,reptilia) from the early Pleistocene of Cooper's Cave (South Africa): taxonomy and further implications for the herpetofaunal studies of the plio-pleistocene sites from the Cradle of Humankind

Vilakazi, Nonhlanhla 01 July 2014 (has links)
South Africa is well known for its many, important fossil bearing deposits of Plio-Pleistocene age. Many of these sites contain abundant remains of extinct and extant animals including hominins. Non-herpetological fauna have been used to reconstruct important information about past environments and for chronological data. This study tried a different method; using herpefauna to establish past environments of Cooper’s Cave. Herpetological fauna potentially have numerous advantages in their use for such questions, including typically limited ranging behaviors, and specific temperature requirements. Despite these advantages only a few studies have even mentioned the presence of squamate fauna in the fossil assemblages of these sites. This study has demonstrated that herpefauna exists, in reasonable levels of abundance and with adequate preservation within the fossil record of the dolomitic region now known as the Cradle of Humankind. It has also demonstrated for the first time the presence of a relative abundance of herpefauna at numbers far greater than any previous study has recognized. The present study was however, handicapped in not being able to fully utilize the material at hand to interpret past environments, owing to the lack of comparative material needed to move beyond the family or generic level in most cases with any degree of confidence. However, Agamids and Pseudocordylids were described to generic level. However, the many shortcomings that this work highlighted should not be seen as reason not to pursue the study of herpefauna, but to improve present comparative collections and collecting methods around the fossils themselves.
286

Macro-faunal exploitation in the Cape Floral Region (Fynbos Biome) of the southern Cape, South Africa c. 75-60 ka: case studies from Blombos Cave and Klipdrift Shelter

Reynard, Jerome Peter January 2016 (has links)
A thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy. 2016 / The analysis of faunal remains from archaeological sites can reveal much about past behaviour, palaeoenvironments and bone technology. This is especially pertinent for the Middle Stone Age (MSA): a period that corresponds to both the behavioural and anatomical development of Homo sapiens. In this thesis, I examine the faunal remains from Blombos Cave (BBC) and Klipdrift Shelter (KDS), two significant MSA sites about 45 km apart along the present-day southern Cape coast. The focus of the analyses is on the Still Bay (SB) layers (c. 75 – 68 thousand years ago [ka]) at BBC and the Howiesons Poort (HP) layers (c. 65 – 59 ka) at KDS. The aim of this thesis is to explore subsistence behaviour and environmental conditions during the SB and HP in the fynbos region of the southern Cape. I also investigate the effects of trampling on bone and whether trampling and other types of taphonomic modification can be used to infer occupational intensity in cave and rock shelter sites. Taphonomic data indicate that significant differences exist between the SB and HP faunal assemblages at BBC and KDS, respectively. Carnivores and scavengers had a greater effect on the SB than on the KDS assemblage. Furthermore, subsistence activities at KDS focused on marrow extraction while filleting was probably an important strategy at BBC. Taxonomic analyses indicate that the representative fauna from both sites is generally consistent with what is expected in the fynbos biome but with some noticeable differences. Grazers, for example, are significantly more prevalent at KDS than BBC while seal is more common at BBC. Other zooarchaeological data also show differences in prey selection strategies. Diet breadth is more extensive at KDS than at BBC, although bovid mortality profiles at BBC are more juvenile-dominated. I propose that many of these contrasting patterns imply that subsistence intensification is more evident in the HP layers at KDS than in the SB at BBC. Moreover, the taphonomic data suggest that the SB at BBC was a low-intensity, sporadically occupied period in contrast to the high-intensity occupations, particularly during the middle layers of the HP at KDS. The results of the KDS analysis also indicate a shift in environmental conditions during the HP and show links between prey selection, the environment and occupational intensity during this period. Trampling experiments indicate that trampling can generally be distinguished from butcherymarks, although bioturbation in shelly deposits can sometimes result in marks that mimic cutiii marks. More importantly, experiments show that pitting and abrasion are a more significant indicator of trampling than lines that resemble cut-marks. Based on these experiments, I argue that trampling modification can be used to infer occupational intensity at archaeological sites. Trampling marks in the KDS assemblage, for example, correspond well with the high occupational periods as indicated by other taphonomic data. Trampling and taphonomic data support the notion that BBC was a low-intensity, sporadically occupied site during the SB. By incorporating taxonomic, taphonomic and novel methods of skeletal-part analyses, this study contributes to our knowledge of human subsistence and palaeoenvironments during the SB and HP in the southern Cape. This thesis strengthens and adds to other research that has demonstrated variability in subsistence behaviour during the MSA. / LG2017
287

Testing Crayfish Evolutionary Hypotheses with Phylogenetic Methods

Breinholt, Jesse W. 16 May 2012 (has links)
This dissertation focuses on increasing the understanding of the evolution processes that have contributed to the diversification of freshwater crayfish. Chapter one estimates the divergence time of the three crayfish families and tests the hypothesis that diversification is tied to the break-up of Pangaea, Gondwanna, and Laurasia. I find that the families of crayfish diverged prior to or in association with the break-up of the three super continents. Chapter two addresses the evolutionary history of the genus Cambarus, using molecular data to test hypotheses of relationships based on chela and carapace morphology. The results provide evidence that the morphology used to determine Cambarus relationships do not reflect evolutionary history and that convergent evolution of morphological traits is common in crayfish. Chapter three addresses evolution at the population level and tests for differences in the genetic population structure of two crayfish with different physiological needs. I find that physiological requirements of these crayfish have influenced their population genetic structure. The last chapter addresses a molecular based hypothesis that rates of mitochondrial evolution are reduced in cave crayfish that have increased longevity, reduced metabolism, and restricted diets compared to surface crayfish. I find that cave crayfish rates of mitochondrial evolution do not significantly differ from surface crayfish. Therefore, increased longevity, reduced metabolism, and restricted diets do not slow the rate of mitochondrial evolution as predicted in this group of cave crayfish.
288

Development of a Karst Tourism Management Index to Assess Tourism-Driven Degradation of Protected Karst Sites

Semler, Keith R 01 July 2019 (has links)
The intent of this research was to create and evaluate a karst tourism management index (KTMI). This index is intended to be a new management tool designed to quantify environmental disturbances caused specifically by tourism activities in karst regions, particularly show caves and springs. In an effort to assess the effectiveness of the index as a management tool in karst terrains, after development, the index was applied to six case study sites. A review of the management policies at each study site was conducted with the use of standard policy critique methods and semistructured interviews with managers at the study sites. After interviews were completed, the newly created index was applied to the study areas with the aid of park land managers. Including land managers in the application process allowed for active land managers to provide more meaningful feedback on potential improvements to the KTMI to ensure the most universally applicable and thoroughly field-tested index tool was created. Upon application and continual refinement of the index to the six study sites, a new data-driven management tool to measure disturbances to karst terrains by tourism was developed. The KTMI consist of an Overall Score category that is broken down into the two main categories of Management and Tourism. The KTMI contains 168 indicators that all need to be scored individually to obtain results, with Management containing 100 of the indicators and Tourism containing the other 68 indicators.
289

The Bachman Cave (10-OE0565) point typology, Owyhee County, southwestern Idaho

Chavarria, Juan C. 04 September 2002 (has links)
In the past, archaeological investigations have recovered material culture that have often been stored as museum property without a focused analysis or written report of the results. This study focuses on one such assemblage ofchipped stone projectile points from the Bachman Cave locality of southwestern Idaho that has been stored at the Southwest Idaho Regional Archaeological Center (SWIRAC) for over twenty years. The focus of this study outlines the approach used to develop the cultural chronology of the site by conducting an objective and subjective analysis of the projectile points, using previous and recent literature as well as field notes, level records, and published radiocarbon samples to corroborate the data. Overall, this study presents a cultural sequence of a site in southwestern Idaho as it is revealed by the identification and analysis of Bachman Cave projectile points. The Bachman Cave projectile point database is consistent with a known analytical scheme and this will greatly add to future archaeological investigations conducted in the Snake River Plain of Idaho and the Northern Great Basin region. / Graduation date: 2003
290

The search for ancient hair: a scientific approach to the probabilities and recovery of unattached hair in archaeological sites

Turner-Pearson, Katherine 15 May 2009 (has links)
A recent upsurge exists of archaeologists using ancient hair as a research tool, with new uses of this previously discarded archaeological material being introduced annually. Human hair deteriorates extremely slowly, and since the average modern human sheds approximately one hundred hairs per day, there should be copious amounts of hair debris left behind after humans leave a site; it is just a matter of how much of the hair survives in the archaeological environment. Most loose hair recovered from archaeological sites, however, is found fortuitously and in many cases, because archaeologists were not actively searching for ancient hair, it is possible they tainted the hair they later tested in ways that compromised their data, or more importantly contaminated their samples with modern hair and did not test ancient hair at all. No standardized method has previously been established for searching for ancient hair in an archaeological site. This paper considers (a) a method of soil extraction in the field that avoids contamination with modern hair and elements that might hinder later test data; (b) the processing of samples in the laboratory while continuing sample integrity; (c) identification of the types of soils and environments that are most favorable to hair preservation; and (d) an examination of the relevance of hair extraction from sites including the practicality and research potential. This paper examines five archaeological sites, using three different methods of hair extraction, examining the pros and cons of each. This should enable future researchers to find a method that works best for their particular site. It also analyzes the soil chemistry of the sites in order to study the soil and hair survival relationship, so that scientists can better determine which soils hold the best potential for hair survival. Laboratory methods that avoid contamination of the samples are also outlined in order to help researchers keep sample integrity after leaving the archaeological site.

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