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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.
271

Dating human occupation and adaptation in the southern European last glacial refuge: The chronostratigraphy of Grotta del Romito (Italy)

Blockley, S., Pellegrini, M., Colonese, A.C., Lo Vetro, D., Albert, P.G., Brauer, A., Di Giuseppe, Z., Evans, Adrian A., Harding, P., Lee-Thorp, J., Lincoln, P., Martini, F., Pollard, M., Smith, V., Donahue, Randolph E. 10 February 2020 (has links)
Yes / Grotta del Romito has been the subject of numerous archaeological, chronological and palaeoenvironmental investigations for more than a decade. During the Upper Palaeolithic period the site contains evidence of human occupation through the Gravettian and Epigravettian periods, multiple human burials, changes in the pattern of human occupation, and faunal, isotopic and sedimentological evidence for local environmental change. In spite of this rich record, the chronological control is insufficient to resolve shifts in subsistence and mobility patterns at sufficiently high resolution to match the abrupt climate fluctuations at this time. To resolve this we present new radiocarbon and tephrostratigraphic dates in combination with existing radiocarbon dates, and develop a Bayesian age model framework for the site. This improved chronology reveals that local environmental conditions reflect abrupt and long-term changes in climate, and that these also directly influence changing patterns of human occupation of the site. In particular, we show that the environmental record for the site, based on small mammal habitat preferences, is chronologically in phase with the main changes in climate and environment seen in key regional archives from Italy and Greenland. We also calculate the timing of the transitions between different cultural phases and their spans. We also show that the intensification in occupation of the site is chronologically coincident with a rapid rise in Mesic Woody taxa seen in key regional pollen records and is associated with the Late Epigravettian occupation of the site. This change in the record of Grotta del Romito is also closely associated stratigraphically with a new tephra (the ROM-D30 tephra), which may act as a critical marker in environmental records of the region. / Leverhulme Trust (F/0 0235/I) and by a Natural Environment Research Council ORADS radiocarbon dating award (NF/2011/2/7).
272

A “Drastic” Evaluation of the Ground-Water Pollution Potential of Karst Terrain: Lost River Ground-Water Basin, Warren County, Kentucky

Baize, David 01 April 1990 (has links)
Karst terrains, such as the Lost River Karst Ground-Water Basin, are extremely vulnerable to ground-water contamination. Seven physical factors: depth to water, recharge, aquifer media, soil media, topography, impact of the vadose zone, and hydraulic conductivity, are evaluated using the DRASTIC system to determine the ground-water pollution potential of the study area. A numerical value is calculated for each of the seven factors, and a map layer for each factor is produced. These layers are then “added” together to produce a DRASTIC ground-water pollution potential map. The effectiveness of each factor in evaluating the pollution potential of karst terrain is discussed. It was determined that small scale hydrogeologic features unique to karst areas provide significant influences on contaminant transport that are not addressed by the DRASTIC methodology. Therefore, it is recommended that modifications to the DRASTIC system be made by the users of the DRASTIC system when evaluating the pollution potential of a karst terrain.
273

The Third-phase of the Yungang Cave Complex—Its Architectural Structure, Subject Matter, Composition and Style

Yi, Lidu 05 September 2012 (has links)
Abstract The Yungang Cave Complex in Shanxi province is one of the largest Buddhist sculpture repositories produced during the Northern and Southern Dynasties. This thesis argues that the iconographic evolution of the Yungang caves underwent three developing phases which can be summarized as the five Tan Yao Caves phase, the transitional period, and the sinicized third-phase under the reigns of five Northern Wei (386-534) emperors Wencheng 文成 (452-465), Xianwen 獻文 (466-471), Xiaowen 孝文(471-499), Xuanwu 宣武 (500-515) and Xiaoming 孝明 (516-528). This dissertation studies the Yungang third-phase caves, namely those caves executed after the capital was moved from Pingcheng 平城 to Luoyang 洛陽in the year 494. It focuses primarily on what we call the western-end caves, which are composed of all the caves from cave 21 to cave 45, and as cave 5-10 and cave 5-11 are typical representations of the third-phase and even today are well preserved, they are also included in this study. Using typology method, as well as primary literary sources, this study places the western-end caves in their historical, social and religious context while focusing on four perspectives: architectural lay-out, iconographic composition, subject matter and style of representation. It deals with such questions as: what these images represent, what is their connection with Buddhist literature, what is the origin of the style of the western-end caves, what is the relationship between sculpture and painting, what is the relationship between the monastic life and Buddhist art, what was the status of Yungang after the transfer of the capital to the south, and who were the patrons. This study sheds new light on the changes in the iconographic motifs over the time from the first-phase to the third-phase and constructs a timeline for the sequence of construction of the western-end caves. The study also investigates the iconographical inter-relationship between the Yungang third-phase caves and those in the Longmen and to a lesser extent, the Gongxian complexes, as well as some relatively small caves in Shanxi province in order to trace the spread of the “Yungang Style.” This will map out the evolution in Buddhist iconographical style throughout the Central Plain of China. Although the caves of the first two phases have been studied extensively, this study is the first comprehensive examination of the Yungang third-phase caves. It is also the first investigation of the interrelationship between the Yungang style and that of other sites such as Longmen and Gongxian, as well as individual caves in the Shanxi area. This work is based on a broad consultation of primary text material and, most importantly, on first hand site observations by the researcher, which are documented by an extensive photographic record.
274

The Third-phase of the Yungang Cave Complex—Its Architectural Structure, Subject Matter, Composition and Style

Yi, Lidu 05 September 2012 (has links)
Abstract The Yungang Cave Complex in Shanxi province is one of the largest Buddhist sculpture repositories produced during the Northern and Southern Dynasties. This thesis argues that the iconographic evolution of the Yungang caves underwent three developing phases which can be summarized as the five Tan Yao Caves phase, the transitional period, and the sinicized third-phase under the reigns of five Northern Wei (386-534) emperors Wencheng 文成 (452-465), Xianwen 獻文 (466-471), Xiaowen 孝文(471-499), Xuanwu 宣武 (500-515) and Xiaoming 孝明 (516-528). This dissertation studies the Yungang third-phase caves, namely those caves executed after the capital was moved from Pingcheng 平城 to Luoyang 洛陽in the year 494. It focuses primarily on what we call the western-end caves, which are composed of all the caves from cave 21 to cave 45, and as cave 5-10 and cave 5-11 are typical representations of the third-phase and even today are well preserved, they are also included in this study. Using typology method, as well as primary literary sources, this study places the western-end caves in their historical, social and religious context while focusing on four perspectives: architectural lay-out, iconographic composition, subject matter and style of representation. It deals with such questions as: what these images represent, what is their connection with Buddhist literature, what is the origin of the style of the western-end caves, what is the relationship between sculpture and painting, what is the relationship between the monastic life and Buddhist art, what was the status of Yungang after the transfer of the capital to the south, and who were the patrons. This study sheds new light on the changes in the iconographic motifs over the time from the first-phase to the third-phase and constructs a timeline for the sequence of construction of the western-end caves. The study also investigates the iconographical inter-relationship between the Yungang third-phase caves and those in the Longmen and to a lesser extent, the Gongxian complexes, as well as some relatively small caves in Shanxi province in order to trace the spread of the “Yungang Style.” This will map out the evolution in Buddhist iconographical style throughout the Central Plain of China. Although the caves of the first two phases have been studied extensively, this study is the first comprehensive examination of the Yungang third-phase caves. It is also the first investigation of the interrelationship between the Yungang style and that of other sites such as Longmen and Gongxian, as well as individual caves in the Shanxi area. This work is based on a broad consultation of primary text material and, most importantly, on first hand site observations by the researcher, which are documented by an extensive photographic record.
275

Léčebna se speleoterapií Ostrov u Macochy / Sanatorium with Speleotherapy Ostrov u Macochy

Hendrych, Pavel January 2016 (has links)
The diploma project proposes The Children´s Sanatorium with Speleotherapy Ostrov u Macochy which is to take place in the Císařská Cave. Site is located close to the mentioned cave in an exposed natural environment adjacent by urban housing which is represented by dispersed detached houses. An ambition of project is connecting an existing down-entrance to Císařská Cave with design new up-entrance, building of speleotherapy and existing development. There is created a new interconnection which respects and supports a local morphology. The building is situated on the end of connector in direct continuity with existing roads and development which suitably complements because of architecture form based on an archetyp of traditional cottage. The complex offers services for rehabilitation, sanatorium, accommodation and sports for childrens clients and general public too. A project intention was an effort to maximize incorporation the volume to feature of town, townscape with gabled roofs and natural surroundings with preservation high users comfort.
276

The Dominance of the Archaea in the Terrestrial Subsurface

Johnston, Michael David January 2013 (has links)
No description available.
277

The Significance of Access: Students with Mobility Impairments Constructing Geoscience Knowledge Through Field-Based Learning Experiences

Atchison, Christopher Lawrence 22 July 2011 (has links)
No description available.
278

Casas cueva de la Comarca del Vinalopó Medio (Alicante)

Martínez Antón, Alicia 02 September 2021 (has links)
[ES] El trabajo aquí desarrollado pretende sacar a la luz un valioso patrimonio de 1.018 casas-cueva existentes en la comarca del Vinalopó Medio en la provincia de Alicante, con escasas referencias publicadas hasta el momento por los investigadores dedicados a la materia. Abordar el conocimiento de este extenso conjunto excavado ha supuesto un extraordinario reto para el que ha sido necesario estructurar la investigación en diversas fases, la primera, ineludible, la localización y censado de todas ellas. A partir de esta primera etapa se desarrolla toda una labor que tiene como fin último la puesta en valor de las casas-cueva de la comarca y sentar las bases para lograr el reconocimiento y la debida protección patrimonial por parte de las administraciones. Así, el estudio llevado a cabo se centra en la identificación de las características de los núcleos de cuevas hasta definir la tipología propia de los asentamientos de la zona y la morfología interna del espacio excavado, para, seguidamente, establecer un análisis comparativo con otros conjuntos de España. Se completa la investigación con la evaluación del estado actual de conservación de estas viviendas a través de la identificación de los daños y lesiones y con la aportación de técnicas y actuaciones de restauración. Igualmente, se verifican las extraordinarias condiciones de confort ambiental interior de las casas-cueva. El trazado de todo este trabajo culmina con la propuesta de dos estrategias de intervención que procuran aprovechar los recursos de la comarca y promocionar la recuperación del uso como vivienda de estas cuevas. / [CA] El treball ací desenvolupat pretén traure a la llum un valuós patrimoni de 1.018 cases-cova existents a la comarca del Vinalopó Mitjà a la província d'Alacant, amb escasses referències publicades fins al moment pels investigadors dedicats a la matèria. Abordar el coneixement d'aquest extens conjunt excavat ha suposat un extraordinari repte per al qual ha sigut necessari estructurar la investigació en diverses fases, la primera, ineludible, la localització i censat de totes elles. A partir d'aquesta primera etapa es desenvolupa tota una labor que té com a fi última la posada en valor de les cases-cova de la comarca i establir les bases per a aconseguir el reconeixement i la deguda protecció patrimonial per part de les administracions. Així, l'estudi dut a terme se centra en la identificació de les característiques dels nuclis de coves fins a definir la tipologia pròpia dels assentaments de la zona i la morfologia interna de l'espai excavat, per a, seguidament, establir una anàlisi comparativa amb altres conjunts d'Espanya. Es completa la investigació amb l'avaluació de l'estat actual de conservació d'aquests habitatges a través de la identificació dels danys i lesions i amb l'aportació de tècniques i actuacions de restauració. Igualment, es verifiquen les extraordinàries condicions de confort ambiental interior de les cases-cova. El traçat de tot aquest treball culmina amb la proposta de dues estratègies d'intervenció que procuren aprofitar els recursos de la comarca i promocionar la recuperació de l'ús com a habitatge d'aquestes coves. / [EN] This work has the aim of bring to light a valuable heritage of 1.018 cave-houses located at the Vinalopó Medio in the province of Alicante, with few published works to date by researchers in the field. To address the knowledge of this huge excavated complex has led a tremendous challenge and, in consequence, it has been necessary to divide the research along different phases, first of all, unavoidable, the location and census of all of them. After this first stage, a long task has been carried out with the ultimate goal of calling attention to the value of the cave-houses at this area and lay the basis to achieve the recognition and the correct equity protection by the public administrations. In this way, the work performed is focused in the identification of characteristics of the cave areas to define the representative typology of the settlements in the area and the internal morphology of the excavated complex and, then, carry out a comparative analysis with other cave areas in Spain. The thesis work is completed with the evaluation of the current conservation status of these dwellings through the identification of damages and the proposal of techniques and actions for their restoration. In the same way, the extraordinary indoor environmental comfort conditions of cave-houses are confirmed. All this work finalizes with the proposal of two intervention strategies which seek to leverage the resources of the area and facilitate the original use of these cave-houses as dwellings. / Martínez Antón, A. (2021). Casas cueva de la Comarca del Vinalopó Medio (Alicante) [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/171457
279

Determining the effect of polluted mine water on the ecosystem health of a karstic cave environment in the Witwatersrand Basin / Gerhard Cornelis du Preez

Du Preez, Gerhard Cornelis January 2014 (has links)
The Wonderfontein Cave is located within the Witwatersrand Basin (Gauteng province, South Africa) and is associated with the river banks of the Wonderfontein Spruit. This cave system has for many years been subjected to the influx of polluted mine water. Since subterranean environments remain poorly studied, it is unknown what the effect of this might be on the associated ecosystem. Furthermore, water that enters the Wonderfontein Cave poses a severe health threat as it drains into the underlying aquifer, which is abstracted for human and animal use. The general aim of this study was to determine the extent of metal pollution (enrichment), as well as to study the toxicity hazard potential of the soils and sediments associated with the Wonderfontein Cave. The objectives of this study were to (1) quantify the extent of anthropogenic metal pollution of water, soils and sediments associated with the Wonderfontein Cave (2) and assessing the toxicity hazard potential of these substrates; (3) determining whether nematode taxa and C. gariepinus individuals represent isolated communities and a population within the Wonderfontein Cave, respectively; (4) measuring the effect of mining-associated pollutants on the soil and sediment health of the Wonderfontein Cave by making use of nematodes to serve as bioindicators; (5) evaluating and comparing biomarker responses to metal bioaccumulation in C. gariepinus populations associated with the Wonderfontein Cave and epigean (surface) environments and lastly (6) comparing the results of the above identified assessments over both a temporal and spatial scale. Sampling was undertaken during April (1st sampling interval) and September (2nd sampling interval) 2013, which respectively represented the end of the high and low flow periods. Also, sampling of the subterranean (Wonderfontein Cave) and associated surface (Wonderfontein Spruit) environments were undertaken. The findings of this study suggested that especially the sediments associated with the Wonderfontein Cave have been subjected to severe nickel, copper, zinc, cobalt, aluminium, cadmium, lead and uranium enrichment. Also, the concentrations of many of the studied metals exceeded the respective water, soil and sediment environmental quality guidelines. Thus, also taking into consideration that most of the sediments were classified as being toxic, a severe threat is posed to the health of the associated biota. Although 60 nematode genera were identified from soil and sediments samples collected from the respective sampling sites associated with the Wonderfontein Cave and Spruit, it was concluded that most of these genera were likely only temporary residents of the subterranean environment. Even though plant-parasitic and nonparasitic nematodes were present, most of the collected soil and sediment samples were dominated by bacterivores (non-parasitic nematodes). Zero genetic divergence was recorded between the C. gariepinus populations associated with the Wonderfontein Cave and Stoffels Dam (Wonderfontein Spruit). However, significant temporal and spatial variation was observed in some bioaccumulated metals and biomarker responses within and between the respective C. gariepinus populations. Furthermore, the metal bioaccumulation levels present in both these fish populations pose a substantial threat to human health and are thus not fit for consumption. Also, no significant fish condition differences were observed between the C. gariepinus populations associated with the Wonderfontein Cave and Spruit. This study served as an initiative to create awareness and promote the conservation of Africa’s karst landscapes. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015
280

Determining the effect of polluted mine water on the ecosystem health of a karstic cave environment in the Witwatersrand Basin / Gerhard Cornelis du Preez

Du Preez, Gerhard Cornelis January 2014 (has links)
The Wonderfontein Cave is located within the Witwatersrand Basin (Gauteng province, South Africa) and is associated with the river banks of the Wonderfontein Spruit. This cave system has for many years been subjected to the influx of polluted mine water. Since subterranean environments remain poorly studied, it is unknown what the effect of this might be on the associated ecosystem. Furthermore, water that enters the Wonderfontein Cave poses a severe health threat as it drains into the underlying aquifer, which is abstracted for human and animal use. The general aim of this study was to determine the extent of metal pollution (enrichment), as well as to study the toxicity hazard potential of the soils and sediments associated with the Wonderfontein Cave. The objectives of this study were to (1) quantify the extent of anthropogenic metal pollution of water, soils and sediments associated with the Wonderfontein Cave (2) and assessing the toxicity hazard potential of these substrates; (3) determining whether nematode taxa and C. gariepinus individuals represent isolated communities and a population within the Wonderfontein Cave, respectively; (4) measuring the effect of mining-associated pollutants on the soil and sediment health of the Wonderfontein Cave by making use of nematodes to serve as bioindicators; (5) evaluating and comparing biomarker responses to metal bioaccumulation in C. gariepinus populations associated with the Wonderfontein Cave and epigean (surface) environments and lastly (6) comparing the results of the above identified assessments over both a temporal and spatial scale. Sampling was undertaken during April (1st sampling interval) and September (2nd sampling interval) 2013, which respectively represented the end of the high and low flow periods. Also, sampling of the subterranean (Wonderfontein Cave) and associated surface (Wonderfontein Spruit) environments were undertaken. The findings of this study suggested that especially the sediments associated with the Wonderfontein Cave have been subjected to severe nickel, copper, zinc, cobalt, aluminium, cadmium, lead and uranium enrichment. Also, the concentrations of many of the studied metals exceeded the respective water, soil and sediment environmental quality guidelines. Thus, also taking into consideration that most of the sediments were classified as being toxic, a severe threat is posed to the health of the associated biota. Although 60 nematode genera were identified from soil and sediments samples collected from the respective sampling sites associated with the Wonderfontein Cave and Spruit, it was concluded that most of these genera were likely only temporary residents of the subterranean environment. Even though plant-parasitic and nonparasitic nematodes were present, most of the collected soil and sediment samples were dominated by bacterivores (non-parasitic nematodes). Zero genetic divergence was recorded between the C. gariepinus populations associated with the Wonderfontein Cave and Stoffels Dam (Wonderfontein Spruit). However, significant temporal and spatial variation was observed in some bioaccumulated metals and biomarker responses within and between the respective C. gariepinus populations. Furthermore, the metal bioaccumulation levels present in both these fish populations pose a substantial threat to human health and are thus not fit for consumption. Also, no significant fish condition differences were observed between the C. gariepinus populations associated with the Wonderfontein Cave and Spruit. This study served as an initiative to create awareness and promote the conservation of Africa’s karst landscapes. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015

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