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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.
201

Projekt cyklistické naučné stezky v Chráněné krajinné oblasti Český kras / Project of Educational cycle trail in the Protected Landscape Area in Bohemian Karst

Tesařová, Alena January 2013 (has links)
Title: Project of Educational cycle trail in the Protected Landscape Area in Bohemian Karst Objective: The objective of this work was to create an Educational cycle trail in the Protected Landscape Area of the Bohemian Karst. The trail, natural and cultural attractions and other information process into guidebook which will be available at tourist information centers and on the Internet. Methods: Collecting and sorting information about the natural and cultural wealth of the region. Summarizing information in guidebook and creating a trail. Subsequent test the applicability of a booklet form of a questionnaire to a group of cyclists who created the route with the completed booklets. Results: The results of this work are two proposal of Educational cycle trail in the Protected Landscape Area of the Bohemian Karst, which are processed into guidebook that contains trail description, information about each trail and map material. The final form of the trail is also based on results of questionnaires and direct responses of testees. The guidebook can be offered to information centers in the area of Bohemian Karst or through them be available in electronic form on the Internet. Keywords: cycling, Educational trail, Protected Landscape Area, Bohemian Karst.
202

Zakládání geoparků v konceptu udržitelného rozvoje na příkladu kandidátského Geoparku Joachima Barranda / Establishing geoparks in concept of sustainable development on the example of Joachim Barrande Geopark

Červinková, Romana January 2014 (has links)
The diploma thesis deals with the application of a new instrument for landscape protection and nature conservation which is the foundation of Geoparks, with a particular focus on the candidate Joachim Barrande Geopark. The aim of this paper is not only to assess the impacts of tourism on this area. Management of establishment of the geopark is discussed, too. The thesis emphasizes the current relations, cooperation and attitudes of the actors. Proposals to improve the efficiency of establishment of Geoparks are an integral part of the paper, too. It also critically appreciates the phenomenon of Geoparks, which is widely discussed in the concept of sustainable tourism. The thesis gives an overview of the legislative restrictions related to the protection of nature and implies the confrontation of the nature conservation interests with the interests of tourism. Key words: sustainable development, tourism, geotourism, geopark, Bohemian Karst
203

Approche pseudo-génétique pour la simulation stochastique de la géométrie 3D de réseaux fracturés et karstiques / Genetic-like approach for 3D stochastic modeling of fractrue and karst networks

Henrion, Vincent 11 July 2011 (has links)
Les réseaux de fractures et les karsts constituent des discontinuités au sein de la roche qui affectent considérablement les écoulements de fluides, ce qui engendre des problèmes spécifiques dans divers domaines des géosciences. La problématique générale consiste à déterminer les caractéristiques géométriques et hydrauliques des réseaux de fractures ou de karsts. La caractérisation et la modélisation de ces structures se heurtent cependant à leur complexité géométrique et à leur distribution spatiale hétérogène. De plus, les observations et données directes concernant aussi bien les fractures et karsts que leur encaissant rocheux restent largement insuffisantes pour décrire avec certitudes leurs caractéristiques. Pour ces raisons, la modélisation de réseaux de fractures ou de karsts est le plus souvent réalisée dans un cadre probabiliste. Des simulations stochastiques de type objet ou pixel sont généralement mise en œuvre pour générer des modèles 3D de fractures ou karsts. Cependant les mécanismes sur lesquels repose ce type d'approche ne permet pas de reproduire toutes la complexité de ces objets naturels et fournit des modèles manquant de réalisme géologique.Dans ces travaux de thèse, nous proposons d'aborder la problématique de la modélisation des fractures et des karsts suivant une approche pseudo-génétique. Il s'agit de contraindre le processus de simulation stochastique de fractures et karsts par des règles géométriques et heuristiques qui imitent les processus physiques gouvernant leur formation. Deux méthodes poursuivant cet objectif ont été développées, l'une adressant la simulation des fractures et la seconde celle des karsts. Les modèles ainsi générés exposent des caractéristiques similaires à celles des réseaux de fractures et karsts naturels. / Fractures and karstic networks are known to significantly affect flow paths and therefore raise specific issues in a wide variety of geoscience fields. The common question beyond these problems isto determine whether there is a network of fractures and/or karstic conduits and if yes what are itsgeometrical and hydraulic characteristics. Characterization and modeling of these features is a challenge for it usually displays complex geometries and heterogeneous spatial distribution. Moreover, in most cases, neither fracture and karst nor their host environment can be observed or described with certainty at all scales and location of relevance. For these reasons, fractures and karstic networks are usually integrated into 3D geological model through a probabilistic framework. Stochastic object- or pixel-based simulations are commonly performed to generate 3D models of fractures and karst but failed to reproduce the whole complexity of these natural objects and 3D models often lack geological realism.To address the issues related to fracture and karst modeling, we present two genetic-like approaches. The motivation of this work is to constrain the stochastic simulation of fractures and karsts by geometrical and heuristic rules which mimic the physical processes governing their formation. The resulting fracture and karst models display similar characteristics as those of natural pattern.
204

Sukcese měkkýších společentev v lomech Českého krasu / Succession of mollusk assemblages in quarries of Bohemian Karst

Kocurková, Alena January 2012 (has links)
Molluscan succession was studied in 18 abandoned limestone quarries of different age in Bohemian Karst. The number of species in studied quarries increases in the time. The less species were found in the oldest quarries. This trend was probably caused by habitat diversity decline although it is not conclusive. The best predictors of mollusk species composition are type of surrounding vegetation, light and the cover of tree layer. It is important to take into account correlations of the other environmental variables with light and the cover of tree layer. Compositions of mollusk assemblages of north and south-facing slopes differ, but these differences diminish with ongoing succession. Quarries represent suitable model sites for the study of succession.
205

Prostorová a letová aktivita mateřské kolonie vrápence jižního Rhinolophus euryale ve Slovenském krasu / Spatial and flight activity of the maternity colony of the Mediterranean horsheshoe bat Rhinolophus euryale in Slovak Karst

Jehličková, Veronika January 2013 (has links)
In the pre-lacation, lactation and post-lactation periods in 2010 and 2011 and the pre-lactation period in 2012 we used radio-telemetry to determine changes in home range and habitat activity and preference of the maternity colony of the Mediterranean horseshoe bat (Rhinolophus euryale) in Slovak Karst. The colony roosted in the attic of the monastery in Jasov. This area represents the northern margin of the species distribution range. In total, we tagged 35 females that were radio-tracked for 31 nights. For the all pre- lactation periods 17 females were marked, in the lactation periods 12 females were marked, and 6 females were marked in the post-lactation periods. The females were marked with radiotags and the VHF telemetry (radio telemetry using very high frequencies) was used. We compared the spatial and habitat preferences in the above defined seasons of the annual reproductive cycle. The total number of recorded locations was 858 for all reported periods. We compared the varios aspects of activity of the females during the night in the particular periods. We have shown that the females left their roost in the pre-lactation periods as the most late. These were followed by the females in the lactation periods and as the most early after the sunsetthe roost was left by the females in the...
206

Jeskyně a jejich ochrana v právu / Caves and their legal protection

Chvátalová, Eva January 2017 (has links)
This diploma thesis aims at Czech legislation related to conservation of caves both in terms of its link to the protection of caves as subterranean spaces and parts of the natural environment and of its relation to other fields of expertise, including legal studies (e.g., mining law) and other disciplines (e.g., geology, carsology). First, our attention is paid to definition of the term "cave" and to links of the term to natural sciences. Further, we analyse the development of legal conservation of caves and approaches to caves as a subject of legislation per se. The example of Slovenia - being a prominent speleological country with recognized legislation in terms of its quality and detail - is used in order to compare Czech approaches to cave conservation. Concerning the practical issues, we present an example of conservation effort devoted to one single cave in Czechia, which enables to describe functioning of legal conservation tools, including the themes where these tools overlap. We also present and discuss the only one Czech case-law dealing with the legal aspect of caves.
207

Možnosti krasovění v přechodní facii České křídové pánve / Possibilities of Karstification in the Transitional Facies of the Bohemian Cretatious Basin

Balák, František January 2015 (has links)
In the region of Bohemian Cretaceous Basin can be found some springs with specific yield over 100 l/s. The doyen of Czech hydrogeology Prof. Hynie described some of those springs to be of karst origin and as the most permeable area he described the so-called transitional facies between shallow-water sandstones and deep-water marlstones. Possibilities of karstification have not yet been studied for rocks in the BCB, so the origin of well-permeable pathways in the BCB is a subject of speculations. This thesis deals with the question of which sedimentary rocks potentially allow the generation of karst permeability in the BCB. To do so, rock samples drilled from outcrops in the BCB were subjected to a fast dissolution simulation by leaching in hydrochloric acid. Carbonate content is measured by a standard and one's own method. Mineral composition, grain size and microscopic structure of rocks are studied with SEM. As is shown, the border of rock karstification is not defined just by the carbonate content, but also the grain size, rock structure and by the occurrence of fine secondary silicate content. Concerning the amount of dissolvable compounds, the border of total disintegration can be at 30 % of carbonate content for some rocks, but the most resistant rocks (mostly fine rocks with SiO2 matrix) stay intact...
208

The Lower Reaches of Long Creek, Kentucky: A Karst Anomaly in Allen County

Conner, Doral 01 June 1976 (has links)
A field study of the lower reaches of the Long Creek drainage area in southeastern Allen County, Kentucky, established the karst character of that area. The area heretofore had been described as a non-karst area. Four swallow holes, which individually or collectively totally pirate Long Creek, were identified. Two major resurgences of the pirated flow were located and described. A detailed study of a portion of the Long Creek drainage area revealed thirty-four springs, all of which were pirated at least once, and no flow from these springs reached Long Creek by surficial routes. The field survey also revealed dolines and a major cavern, Carpenter’s Cave. The geologic formation responsible for the karst features within the Long Creek drainage area is the Louisville limestone of Silurian age. These strata are characteristically karstic wherever exposed. The impermeability of the Chattanooga shale which overlies the Louisville limestone was established by the analysis of spring piracy and resurgence. The phreatic character of the Carpenter’s Cave and other karst features led to the conclusion that these karst features were developed prior to the deposition of the impermeable Chattanooga shale during Devonian time.
209

Processos de formação de um depósito fossilífero em abismo na gruta Cuvieri (MG): taxonomia, tafonomia e distribuição espacial de fósseis de mamíferos do Pleistoceno / Formation processes of a fossiliferous pitfall deposit in Gruta Cuvieri (MG): taxonomy, taphonomy and spacial distribution of mammal fossils from the Pleistocene

Mayer, Elver Luiz 30 June 2011 (has links)
A ausência de informações sobre a fauna de mamíferos do Pleistoceno brasileiro que vão além de estudos taxonômicos/descritivos e a carência de escavações com um controle estratigráfico mínimo motivaram as intervenções nos depósitos da Gruta Cuvieri (Lagoa Santa, Minas Gerais, Brasil) aplicando-se um método de escavação refinado. Este método registrou em detalhe a distribuição espacial dos fósseis, bem como o contexto sedimentar em que estavam depositados, representando uma investida pioneira para a paleomastozoologia nacional. O objetivo deste trabalho foi caracterizar parte dos fósseis exumados de um dos depósitos escavados, um abismo denominado Locus 3, e compreender melhor os processos relacionados com a formação do pacote fossilífero. Para isso, o material fóssil foi analisado sob duas perspectivas: 1) como elementos esqueléticos, através da análise anatômica e taxonômica e 2) como bioclastos, através da análise tafonômica. Em ambos os casos também foram considerados aspectos da distribuição espacial dos fósseis. Os resultados da análise taxonômica indicaram a presença de 16 indivíduos de Tayassuidae, 9 de Cuniculus paca, 8 de Cervidae, 7 de Cuniculus major e 1 de Panthera onça. Considerando-se estes animais e aqueles identificados em outros trabalhos sobre o Locus 3, a variedade taxonômica representada neste babismo é pequena, indicando uma forte seleção dos grupos incorporados. Com relação ao peso corporal, verificou-se a presença de animais de pequeno, médio e grande porte, sugerindo pouca seleção para esta característica. De acordo com a distribuição espacial dos remanescentes de meso e megamamíferos, os últimos foram depositados apenas mais recentemente, indicando que o potencial para o aprisionamento de animais do Locus 3 tornou-se mais abrangente ao longo do tempo. Os resultados da análise tafonômica indicam que a formação do depósito fossilífero foi complexa, envolvendo processos cuja ação foi muitas vezes simultânea e sobreposta. Dentre os processos analizados, a fragmentação foi o mais intenso, agindo desde a necrólise das carcaças até depois do soterramento final do material. O pisoteio foi identificado como o principal agente de fragmentação do material, seguido pela queda de animais e de blocos de calcário e pela compactação da coluna sedimentar. O intemperismo foi o segundo fator mais importante na alteração das condições originais do material. Este fator modificou a superfície dos ossos de todo o pacote fossilífero, sugerindo que a taxa ii de sedimentação no Locus 3 foi baixa. A abrasão, outro fator analisado, teve uma contribuição modesta na alteração do material, ocorrendo principalmente na superfície e devido à ação da água, que por sua vez foi importante para o retrabalhamento do material. Carnívoros e roedores também tiveram uma pequena contribuição na formação do pacote fossilífero. A distribuição espacial das peças remontadas indica predominância da dispersão de ossos em superfície e em diferentes momentos da formação do pacote fossilífero. Além disso, as mudanças pós-deposicionais dos sedimentos foram importantes para a dispersão vertical de peças remontadas. Por último, a natureza confinada do abismo, a alta densidade de fósseis e a baixa taxa de sedimentação favoreceram a mistura vertical e horizontal de ossos/dentes de diferentes indivíduos e táxons. A complexidade identificada na formação do depósito tem implicações para o estudo de sítios em cavernas, especialmente no que diz respeito ao uso da associação espacial de fósseis para subsidiar interpretações deposicionais e paleoambientais. / The absence of information from the Brazilian Pleistocene mammalian fauna that goes beyond the taxonomic/descriptive studies and the lack of excavations with minimal stratigraphic control motivated the interventions in the Gruta Cuvieri (Lagoa Santa, Minas Gerais, Brazil) deposits applying a fine resolution excavation method. This method recorded in detail the spacial distribution of fossils as well as the sedimentologic context where the fossils were embedded, representing a pioneering foray to the national paleomastozoology. The objective of this work was to characterize part of the fossils exhumed from one of the excavated deposits, a pit named Locus 3, and to better understand the processes related with the development of this fossiliferous package. In order to do so, I analyzed the fossil material under two perspectives: 1) as skeletal elements, through the anatomic and taxonomic analysis and 2) as bioclasts, through the taphonomic analysis. In both approaches I also considered aspects of the spacial distribution of fossils. The results of the taxonomic analysis indicate the presence of 16 individuals of Tayassuidae, 9 of Cuniculus paca, 8 of Cervidae, 7 of Cuniculus major and 1 of Panthera onca. Considering these animals and those identified in other studies of Locus 3 the taxonomic variety represented in this pit is small, indicating a strong selection of groups incorporated therein. With regard to body weight there was the presence of animals of small, medium and large size, suggesting little selection for this feature. According to the spacial distribution of the remains of meso and megamammals, the latter were deposited only more recently, indicating that the Locus 3 potential for trapping animals had become more inclusive over time. The results of the taphonomic analysis indicate that the formation of the fossiliferous deposit was complex, involving processes that were acting often simultaneously and superimposed. Among the processes evaluated, the fragmentation was the most intense, acting from the necrolysis of the carcasses to after the final burial of the material. Trampling was identified as the main agent of material fragmentation, followed by the fall of animals and limestone blocks and by the compression of the sedimentary column. Weathering was the second most important factor in altering the original condition of the material. This feature modified the surfaces of the bone remains all over the fossiliferous package, suggesting slow sedimentation rate in Locus 3. Abrasion, another factor analysed, had a modest contribution in shaping the material, occurring iv mainly in the surface and due to the action of water, which in turn was important for the reworking of the material. Carnivores and rodents had also a small contribution to the fossiliferous package formation. The spacial distribution of the refitted pieces indicates predominance of bones dispersion on surface and at different times of the fossiliferous package formation. In addition, the post-depositional changes of the sediments were important to the vertical dispersion of refitted pieces. Lastly, the confined nature of the pit, the high density of fossils and the slow sedimentation rate favored vertical and horizontal mixture of bones/teeth of different individuals and taxa. The complexity identified in the deposit formation has implications for the study of cave sites, especially with regard to the use of spacial fossils association to subsidize depositional and paleoenvironmental interpretations.
210

Planalto carbonático do André Lopes (SP): geomorfologia cárstica e geoespeleologia da Gruta da Tapagem (Caverna do Diabo) / not available

Cordeiro, Bruna Medeiros 17 December 2013 (has links)
A Serra do André(SAL) Lopes constitui um planalto carbonático de natureza dolomítica desenvolvido no Mármore da Tapagem (Grupo Açungui - Mesoproterozoico) localizada no alto vale do rio Ribeira de Iguape, sul do Estado de São Paulo. Constitui uma das áreas cársticas menos estudadas da região do ponto de vista geomorfológico e geoespeleológico. Dentre as feições mais notáveis estão o Vale Cego da Tapagem, a Gruta da Tapagem (Caverna do Diabo), grandes depressões poligonais e depósitos de tufas. Este trabalho buscou o entendimento da configuração do relevo cárstico da SAL a partir de um mapeamento morfológico de detalhe baseado em fotointerpretação, modelos de terreno, morfometriae zoneamento morfológico. O estudo geoespeleológico da Gruta da Tapagem foi feito a partir da investigação morfológica em planta e seção transversal, correlacionando com a estrutura geológica e topografia. A área cárstica ocupa 46,11% do mármore, o restante é dominado por processos fluviais típicos. O sistema apresenta recarga hidrológica mista, porém em sua maior parte autogênica (82%). A água do carste é drenada por bacias distintas, que têm o rio Pardo como nível de base, no setor sudoeste e o rio Ribeira no setor nordeste da lente carbonática. A análise na escala 1:25.000 permitiu identificar três unidades morfológicas, os vales fluviais, o carste poligonal e o vale cego da Tapagem. O carste poligonal é a feição predominante, em planta constitui um mosaico de polígonos composto por 53 depressões poligonais, em geral amplase delimitadas por divisores e cones cársticos. Representam à fonte de recarga do aqüífero cárstico que drena em direção as unidades de vales fluviais instaladas sobre o mármore. As direções predominantes NE-SW e NW-SE, bem marcadas nas redes de drenagem, arranjo espacial das depressões fechadas, estão relacionadas, respectivamente, aos planos de foliação do mármore e aos diques básicos mesozóicos e fraturas associadas. A dissecação do relevo e o desenvolvimento da porosidade secundária do mármore se deram de forma mais intensa na área que tem o rio Ribeira como nível de base. Neste setor se desenvolvem vales mais entalhados, depressões de maior amplitude e feições marcantes como o vale cego do rio Tapagem. O vale cego sugere uma captura de drenagem pelo desenvolvimento da Gruta da Tapagem em direção ao vale fluvial do rio das Ostras, acarretando no entalhamento de um sistema subterrâneo ímpar no planalto carbonático. A Gruta da Tapagem está inserida no flanco noroeste da sinforma do mármoree localmente ocorre um anticlinal, onde próximo do sumidouro as camadas mergulham para NW e do meio para ressurgência para SE. Quimicamente os carbonatos da caverna foram classificados como dolomitos e dolomitoscalcíticos. Quatro diques de diabásio mesozóicos cortam a caverna de forma quase perpendicular e foram rompidos durante sua evolução. A caverna apresenta uma morfologia meandrante em planta, com 1,3 de sinuosidade, e predomínio de cânions subterrâneos vadosos e salões de abatimento, em seção transversal. Os dados estruturais indicam que o condicionamento estrutural da caverna se dá principalmente pelo bandamento do mármore, fraturas NW-SE, pelo gradiente hidráulico regional e por mudanças pontuais no gradiente hidráulico geradas por obliteração do conduto a partir de processos de abatimento. / The Serra do André Lopes (SAL) constitutes a carbonate dolomitic plateau developed in Tapagem Marble (Açungui Group - Mesoproterozoic) located in the upper valley of the Ribeira de Iguape River, in the south of the State of São Paulo. It is one of the least studied karst areas in the region. Its most notable features include the Tapagem Blind Valley, the Tapagem Cave (Devil\'s Cave), extensive polygonal depressions and tufa deposits. This study sought to understand the configuration of the karst landforms of the SAL through detailed morphological mapping based on photointerpretation, terrain models, morphometry and morphological zoning. The geospeleological study of the Tapagem Cave was conducted based on a plan view and cross-section morphological investigation, correlating this with geological structure and topography, on which this study also focused. The karst area occupies 46.11% of the marble, the remainder being dominated by typical fluvial processes. The system shows mixed hydrological recharge, although most of this is autogenic (82%). The karst water is drained by different basins, which have the Pardo River as a base level in the southwestern sector, and the Ribeira River in the northeastern sector of the carbonate body. Analysis on a scale of 1:25,000 made it possible to identify three morphological units, namely: river valleys, the polygonal karst and the Tapagem blind valley. The polygonal karst is the predominant feature, constituting, in plan view, a mosaic of polygons composed of 53 polygonal depressions, generally ample and delimited by water divides and karst cones. These represent the source of recharge of the karst aquifer, which drains in the direction of river valley units installed upon the marble. The predominant directions of NE-SW and NW-SE, well marked in drainage networks and the spatial arrangement of closed depressions are related, respectively, to marble foliation planes and basic Mesozoic dikes and associated fractures. Dissection of the landscape and development of secondary porosity of the marble came about in a more intense manner in the area that has the Ribeira River as its base level. In this sector, more deeply cut valleys developed, as well as depressions of greater amplitude and such notable features as the blind valley of the Tapagem River. The blind valley suggests drainage capture through development of the Tapagem Cave, in the direction of the Ostras River valley, resulting in the carving out of an unmatched subterranean system on the carbonate plateau. The Tapagem Cave lies on the northwestern flank of the marble synform and, locally, an anticline occurs where, in the vicinity of the sinkhole, layers dip to the NW and from the middle for resurgence to the SE. Chemically, the cave carbonates were classified as dolomites and calcareous dolomites. Four Mesozoic diabase dikes cut through the cave in an almost perpendicular manner and were ruptured during their evolution. In plan view, the cave shows meandering morphology, with a sinuosity of 1.3, and a predominance of vadose underground canyons and breakdown chambers, in transverse section. The data indicate that the cave structure is principally conditioned by banding of the marble and NW-SE fractures, as well as the regional hydraulic gradient and localized changes in the hydraulic gradient generated by obliteration of the conduit as a result of subsidence processes.

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