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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.
1

Estudo da dinâmica atmosférica subterrânea na determinação da capacidade de carga turística na caverna de Santana (Petar, Iporanga, SP)

Lobo, Heros Augusto Santos [UNESP] 21 November 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:19Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-11-21Bitstream added on 2014-06-13T20:23:29Z : No. of bitstreams: 1 lobo_has_dr_rcla.pdf: 7427395 bytes, checksum: e2b8d2ead0e1727cf9fb0f097e0d296b (MD5) / O manejo do turismo em cavernas é um procedimento de organização do uso do espaço cavernícola, visando resguardar sua integridade e, simultaneamente, possibilitar o seu conhecimento e fruição. Em níveis mundiais, este tipo de procedimento vem sendo desenvolvido com base em parâmetros científicos, tendo na capacidade de carga turística um de seus principais enfoques. Todavia, os métodos para a determinação de capacidade de carga existentes, ou atendem apenas a situações muito específicas – como as cavernas que abrigam pinturas rupestres –, ou foram adaptados de situações análogas de manejo turístico em áreas naturais – como trilhas –, o que dificulta a inserção das especificidades do ambiente subterrâneo na obtenção de limites adequados de uso. Partindo deste cenário, foi realizada uma pesquisa de determinação de capacidade de carga na caverna de Santana (Parque Estadual Turístico do Alto Ribeira, Iporanga-SP), com base no estudo de sua dinâmica atmosférica. Para tanto, foram executadas três fases de monitoramento espeleoclimático, além de procedimentos complementares de análise de vetores atmosféricos de dispersão e acúmulo e da interação entre atmosfera e rocha. Quanto aos dados monitorados, a média anual (2009-2010) da temperatura do ar no ambiente externo foi de 19,99 °C e a moda foi 17,9 °C. Os extremos registrados foram entre 32,9 °C (máxima, na estação Externa) e 6,1 °C (mínima, na estação Boca). A máxima no período mais chuvoso foi de 32,9 °C e a mínima de 13,8 °C. No período menos chuvoso, que coincide nesta região com o inverno, a máxima registrada foi de 29,4 °C e a mínima de 6,1 °C. A maior diferença, no entanto, se revelou na média, sendo de 21,35 °C no período mais chuvoso (verão) e de 18,06 °C no período menos chuvoso (inverno). A umidade... / The management of tourism in caves is a procedure which aims to guarantee the cave integrity in a long term basis and, simultaneously, make feasible its sustainable use. In many countries, these procedures are been developed based on scientific parameters and methods, considering the tourist carrying capacity as one of its main focus. However, the existent methods used to determinate the carrying capacity are used just for some specific situations (e.g. the caves which shelter rock art or were adapted from other kind of tourist attractions, as trails and pathways), which difficult the insertion of each cave environment specificities in the procedures of obtaining the carrying capacity. Starting with this scenario, a research was carried out in the cave of Santana (State Tourist Park of Upper Ribeira River – PETAR – Iporanga city, State of São Paulo, southeast of Brazil) to determinate its tourist carrying capacity using the cave atmosphere dynamics. Three phases of speleoclimate monitoring were made, besides of complementary procedures to the analysis of the air flow and its pattern of accumulation and dispersion, together with the interaction between air, rock and water temperature. The annual mean in the period 2009-2010 of air temperature in the external environment was 19,99 °C, and the mode was 17,9 °C. The extreme values were 32,9 °C and 6,1 °C in the external area of the cave. Considering the absence of a drought period in the region, the maximum temperature in the rainy season (south hemisphere summer) was 32,9 °C and the minimum registered was 13,8 °C. In the less rainy season (south hemisphere winter), the maximum and minimum values were, respectively, 29,4 °C and 6,1 °C. The biggest difference, however, was in the mean: 21,35 °C in the summer and 18,06 °C in the winter. The mean of the relative... (Complete abstract click electronic access below)
2

Estudo da dinâmica atmosférica subterrânea na determinação da capacidade de carga turística na caverna de Santana (Petar, Iporanga, SP) /

Lobo, Heros Augusto Santos. January 2011 (has links)
Anexo 1 CD-ROM - apêndice A / Orientador: José Alexandre de Jesus Perinotto / Coorientador: Paulo César Boggiani / Banca: Paulo Milton Barbosa Landim / Banca: João Afonso Zavattini / Banca: Ivo Karmann / Banca: William Sallun Filho / Resumo: O manejo do turismo em cavernas é um procedimento de organização do uso do espaço cavernícola, visando resguardar sua integridade e, simultaneamente, possibilitar o seu conhecimento e fruição. Em níveis mundiais, este tipo de procedimento vem sendo desenvolvido com base em parâmetros científicos, tendo na capacidade de carga turística um de seus principais enfoques. Todavia, os métodos para a determinação de capacidade de carga existentes, ou atendem apenas a situações muito específicas - como as cavernas que abrigam pinturas rupestres -, ou foram adaptados de situações análogas de manejo turístico em áreas naturais - como trilhas -, o que dificulta a inserção das especificidades do ambiente subterrâneo na obtenção de limites adequados de uso. Partindo deste cenário, foi realizada uma pesquisa de determinação de capacidade de carga na caverna de Santana (Parque Estadual Turístico do Alto Ribeira, Iporanga-SP), com base no estudo de sua dinâmica atmosférica. Para tanto, foram executadas três fases de monitoramento espeleoclimático, além de procedimentos complementares de análise de vetores atmosféricos de dispersão e acúmulo e da interação entre atmosfera e rocha. Quanto aos dados monitorados, a média anual (2009-2010) da temperatura do ar no ambiente externo foi de 19,99 °C e a moda foi 17,9 °C. Os extremos registrados foram entre 32,9 °C (máxima, na estação Externa) e 6,1 °C (mínima, na estação Boca). A máxima no período mais chuvoso foi de 32,9 °C e a mínima de 13,8 °C. No período menos chuvoso, que coincide nesta região com o inverno, a máxima registrada foi de 29,4 °C e a mínima de 6,1 °C. A maior diferença, no entanto, se revelou na média, sendo de 21,35 °C no período mais chuvoso (verão) e de 18,06 °C no período menos chuvoso (inverno). A umidade... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The management of tourism in caves is a procedure which aims to guarantee the cave integrity in a long term basis and, simultaneously, make feasible its sustainable use. In many countries, these procedures are been developed based on scientific parameters and methods, considering the tourist carrying capacity as one of its main focus. However, the existent methods used to determinate the carrying capacity are used just for some specific situations (e.g. the caves which shelter rock art or were adapted from other kind of tourist attractions, as trails and pathways), which difficult the insertion of each cave environment specificities in the procedures of obtaining the carrying capacity. Starting with this scenario, a research was carried out in the cave of Santana (State Tourist Park of Upper Ribeira River - PETAR - Iporanga city, State of São Paulo, southeast of Brazil) to determinate its tourist carrying capacity using the cave atmosphere dynamics. Three phases of speleoclimate monitoring were made, besides of complementary procedures to the analysis of the air flow and its pattern of accumulation and dispersion, together with the interaction between air, rock and water temperature. The annual mean in the period 2009-2010 of air temperature in the external environment was 19,99 °C, and the mode was 17,9 °C. The extreme values were 32,9 °C and 6,1 °C in the external area of the cave. Considering the absence of a drought period in the region, the maximum temperature in the rainy season (south hemisphere summer) was 32,9 °C and the minimum registered was 13,8 °C. In the less rainy season (south hemisphere winter), the maximum and minimum values were, respectively, 29,4 °C and 6,1 °C. The biggest difference, however, was in the mean: 21,35 °C in the summer and 18,06 °C in the winter. The mean of the relative... (Complete abstract click electronic access below) / Doutor
3

The seasonality, diversity and ecology of cavernicolous guano dependent arthropod ecosystems in southern Australia

Moulds, Timothy A. January 2006 (has links)
Thesis (Ph.D.)--University of Adelaide, School of Earth and Environmental Sciences, Discipline of Environmental Biology, 2006. / "January 2006" Includes copies of author's previously published works. Includes bibliographical references. Also available in print form.
4

Epikarst Hydrogeochemical Changes in Telogenetic Karst Systems in South-central Kentucky

Jackson, Leah 01 July 2017 (has links)
Telogenetic epikarst carbon sourcing and transport processes and the associated hydrogeochemical responses are often complex and dynamic. Among the processes involved in epikarst development is a highly variable storage and flow relationship that is often influenced by the type, rate, and amount of dissolution kinetics involved. Diffusion rates of CO2 in the epikarst zone may drive hydrogeochemical changes that influence carbonate dissolution processes and conduit formation. Most epikarst examinations of these defining factors ignore regional-scale investigations in favor of characterizing more localized processes. This study aims to address that discrepancy through a comparative analysis of two telogenetic epikarst systems under various land uses to delineate regional epikarst behavior characteristics and mechanisms that influence carbon flux and dissolution processes in south-central Kentucky. High-resolution hydrogeochemical and discharge data from multiple data loggers and collected water samples serve to provide a more holistic picture of the processes at work within these epikarst aquifers, which are estimated to contribute significantly to carbonate rock dissolution processes and storage of recharging groundwater reservoirs on the scale of regional aquifer rates. Data indicate that, in agricultural settings, long-term variability is governed by seasonal availability of CO2, while in urban environments extensive impermeable surfaces trap CO2 in the soil, governing increased dissolution and conduit development in a heterogonous sense, which is often observed in eogenetic karst development, as opposed to bedding plane derived hydraulic conductivity usually observed in telogenetic settings. These results suggest unique, site-specific responses, despite regional geologic similarities. Further, the results suggest the necessity for additional comparative analyses between agricultural settings and urban landscapes, as well as a focus on carbon sourcing in urban environments, where increased urban sprawl could influence karst development
5

Controls on Speleogenesis in the Upper-Mississippian Pennington Formation on the Western Cumberland Plateau Escarpment

Steinmann, Hali 01 October 2018 (has links)
Much of the pioneering work on caves of the Cumberland Plateau (province spanning Tennessee, Kentucky, Alabama, and Georgia) has been stratigraphically located within the Mississippian Bangor and Monteagle Limestones, wherein some of the region’s largest and most spectacular caves occur. Of interest to the understanding of this karst landscape, but severely underrepresented in the literature thereof, are caves and karst features in a heterogeneous sequence of clastics and carbonates known collectively as the Pennington Formation (Upper Mississippian). This work consisted of a regional study of Pennington caves on the western Cumberland Plateau escarpment (Alabama and Tennessee), and a case study of Pennington caves in Savage Gulf State Natural Area (Grundy County, Tennessee). The objective of this research was to determine controls on speleogenesis in the Pennington Formation, using cave geomorphology, dye tracing, and GIS to explore lithologic, hydrologic, and structural influences on karst processes. This resulted in a conceptual model for speleogenesis in the Pennington Formation, with the major controls being: 1) direct and diffuse recharge from the caprock, undersaturated with respect to calcite; 2) thin, horizontally bedded limestones sandwiched by shales and other insoluble rocks; and 3) networks of stress release fractures oriented parallel to major stream valleys. Our present understanding of the Cumberland Plateau could be advanced by further study of karst dynamics in the Pennington Formation.
6

Distribuição da fauna de colêmbolos cavernícolas em matriz de minério de ferro no Quadrilátero Ferrífero, Minas Gerais, sudeste do Brasil

Machado, Thais Gomes 29 April 2016 (has links)
Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2017-07-12T13:17:44Z No. of bitstreams: 1 PDF - Thaís Gomes Machado.pdf: 11679483 bytes, checksum: 13fe8295fee9cbfeadaed5751b61b3f1 (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2017-07-20T12:19:59Z (GMT) No. of bitstreams: 1 PDF - Thaís Gomes Machado.pdf: 11679483 bytes, checksum: 13fe8295fee9cbfeadaed5751b61b3f1 (MD5) / Made available in DSpace on 2017-07-20T12:19:59Z (GMT). No. of bitstreams: 1 PDF - Thaís Gomes Machado.pdf: 11679483 bytes, checksum: 13fe8295fee9cbfeadaed5751b61b3f1 (MD5) Previous issue date: 2016-04-29 / Vale S. A. / In general, cave species have changes in their morphology and physiology as way of adaptation to the environment and are classified as troglobites; eutroglophiles; subtroglophiles and trogloxenes. Compared to epigean ecosystem, the cave ecosystem has low species diversity, dependence of nutrients from the external environment, humidity and stable temperature in the year, therefore, this environment is strongly influenced by external environmental changes, such as mining, deforestation, urbanization, etc. This study examines the distribution of troglobite species of Collembola caves in different lithologies in areas of mining interest. Located in Minas Gerais, the Quadrilátero Ferrífero represents one of the main metallogenetic provinces of Brazil. We examined the biological material deposited in the Reference Collection in the Paraíba Soil Fauna in the Universidade Estadual da Paraíba. Held up the organization of a database with records of occurrence and geographical distribution of species, for the geo-referencing of all wells. We performed the analysis of 1.589 specimens, divided into 16 families, 59 genera and 131 species. Of these, 13 were considered possible troglobites. The species Pararrhopalites sp4, Pararrhopalites sp7, Pseudosinella sp4, Trogolaphysa sp6, Troglobius ferroicus e Troglobius sp2 were confirmed troglobite. Arrhopalites sp2 and Arrhopalites sp3 can be the same specie and is believed that Pseudosinella sp4 move around on MSS and Trogolaphysa sp6 may be experiencing a vicarious process. Human activities and the use of natural resources in this environment entails degradation and local or regional extinction of species. The cave environment acts as excellent places for ecological studies and frequently have endemic species, so it is extremely important to preserve this environment and your fauna. / Em geral, espécies cavernícolas possuem alterações em sua morfologia e fisiologia como forma de adaptação ao ambiente e podem ser classificadas como troglóbias, eutroglófilas, subtroglófilas e trogloxenas. Quando comparados a ecossistemas epígeos, ecossistemas cavernícolas possuem baixa diversidade de espécies, dependência de nutrientes provenientes do meio externo e condições de umidade e temperatura estáveis ao longo do ano. Desta forma, este ambiente é fortemente influenciado por alterações ambientais externas, como a mineração, desmatamento, urbanização, entre outras. O presente estudo tem como objetivo avaliar a distribuição das espécies troglóbias de Collembola em cavernas inseridas em diferentes litologias em áreas de significativo interesse minerário. Localizado em Minas Gerais, o Quadrilátero Ferrífero representa uma das principais províncias metalogenéticas do Brasil. Analisamos o material biológico depositado na Coleção de Referência em Fauna de Solo da Paraíba da Universidade Estadual da Paraíba. Foi realizada a organização de um banco de dados com os registros da ocorrência e a distribuição geográfica das espécies, para o georreferenciamento de todas as cavidades. Foram analisados 1.589 espécimes, divididos em 16 famílias, 59 gêneros e 131 espécies. Destas, 13 foram consideradas possivelmente troglóbias. As espécies Pararrhopalites sp4, Pararrhopalites sp7, Pseudosinella sp4, Trogolaphysa sp6, Troglobius ferroicus e Troglobius sp2 foram consideradas troglóbias. Arrhopalites sp2 e Arrhopalites sp3 podem ser a mesma espécie. Acredita-se que Pseudosinella sp4 locomove-se pelo MSS e Trogolaphysa sp6 pode estar passando por um processo vicariante. As atividades antrópicas e o uso dos recursos naturais nestes ambientes acarretam degradação e extinção local ou regional das espécies. O ambiente cavernícola funciona como locais excelentes para estudos ecológicos e frequentemente abrigam espécies endêmicas, portanto é de fundamental importância à conservação deste ambiente e consequentemente de sua fauna.
7

Influence of Spring Flow Reversals on Cave Dissolution in a Telogenetic Karst Aquifer, Mammoth Cave, KY

Kipper, Chelsey 01 October 2019 (has links)
An often overlooked connection between karst groundwater systems and surface water is spring flow reversal, the flow of river water into karst springs caused by changes in hydraulic gradient. Karst aquifers are subject to the intrusion of river water when the hydraulic head of a base level river is higher than the hydraulic head of a base level spring. When this occurs, the flow out of the spring reverses, allowing river water to enter base level conduits. River water thus becomes a source of recharge into karst basins, transporting both valuable nutrients and harmful contaminants into karst aquifers. The rapid recharge of meteoric water, brief groundwater residence times, and the interconnection of surface and subsurface waters through a variety of karst features necessitates studying groundwater and surface water in karst landscapes as a unified system. This study examines the influence of spring flow reversal on cave dissolution in a telogenetic karst aquifer in Mammoth Cave, Kentucky. Spring flow reversals in Mammoth Cave National Park (MCNP) were first recorded nearly one-hundred years ago, but a high-resolution study measuring the effects of spring flow reversals on dissolution in MCNP, or any other telogenetic karst system, had not been conducted until recently. In this study, high-resolution data were collected for pH, SpC, temperature, and stage, as well as weekly samples for major ion concentrations, alkalinity, and carbon isotopes, from June 2018 to December 2018. Surface water and groundwater data were used to quantify the complex hydrologic processes associated with the spring flow reversals, including seasonal changes in karst geochemistry and dissolution taking place between the Green River, River Styx Spring, and Echo River Spring. Data show distinct changes in geochemical parameters as flow reversals occur, with temperature being the principal indicator of flow direction change. During this study, all ten stable reverse flows coincided with increased discharge from the Green River Dam. The predominant drivers of dissolution in the River Styx and Echo River karst basins are storm events and seasonal changes in the hydrologic regime, rather than seasonal CO2 production, normal baseflow conditions, or stable reverse flow events. Estimated dissolution rates generally show that stable reverse flows contribute no more to dissolution than normal baseflow conditions – the highest amount of dissolution during a single stable reverse flow was only 0.003 mm. This is contrary to flow reversal studies in an eogenetic karst system in Florida, which estimated 3.4 mm of wall retreat during a single spring flow reversal. These contrasting results are likely due to significant differences in pH of river water, matrix porosity of the bedrock, basin morphology, and flow conditions.
8

Landscape Evolution of the Central Kentucky Karst

Bosch, Rachel 04 October 2021 (has links)
No description available.
9

Groundwater Flow Tracing in Carter Saltpeter Cave and Toll Branch, Carter County, TN

Doyka, Aaron G 01 August 2017 (has links) (PDF)
Groundwater tracing studies have shown a well-developed conduit system in the karst aquifer beneath the Buffalo Creek Watershed of Carter County, TN. Groundwater can quickly travel beneath topographic divides, transporting contaminants. Using GIS and field reconnaissance, two sites were selected for a two phase dye trace study. In May-June 2016 groundwater resurgences were located using activated carbon samplers, and in October-December 2016 flow velocities were measured using ISCO automatic water samplers. In study 1, a stream sinking in the back of Carter Saltpeter Cave was traced to its resurgence at Cave Springs Cave. In study 2, the dye mass centroid passed the resurgence 23.2 hours after injection. During study 1, dye injected into a sinkhole near the headwaters of Toll Branch rapidly diffused into multiple conduits. In study 2, dye from the Toll Branch site was not recovered, indicating that groundwater follows different flow paths dependent on water table level.
10

GREENHOUSE GASES AND HYDROCLIMATE VARIABILITY IN THE CARIBBEAN: A NEW SPELEOTHEM RECORD SHEDDING LIGHT ON MILLENNIAL AND ORBITAL-SCALE CHANGES

Zhang, Meilun 01 September 2023 (has links) (PDF)
Hydroclimate evolution in the northern Caribbean region has been investigated by several studies, but they offer contradicting results and none of them cover a full glacial-interglacial transition to examine orbital climate forcing. Here we present refined U-Th dating and oxygen isotope (δ18O) data from a stalagmite named Katún collected from Rio Secreto cave in the Yucatan Peninsula that discontinuously spans the time interval between 198 thousand years (kyr) before present (BP) to 320 kyr BP. Stalagmite δ18O is interpreted to reflect precipitation amount variability as established by previous studies from this cave. On orbital timescales, we identified marine isotope stages (MIS) 7, 8, and 9 in the Katún stalagmite δ18O record. The average stalagmite δ18O value during MIS 7 and 9 interglacial intervals is ~-4.5‰, suggesting wetter conditions than the glacial MIS 8 with an average δ18O value of ~-3‰. The stalagmite δ18O record exhibits higher amplitude δ18O and thus precipitation variability, and an increase in the frequency and intensity of drought events during the drier glacial interval. The record suggests a strong link between atmospheric greenhouse gases, CO2 andCH4, and precipitation variability in the Caribbean, which affects hydroclimate via changes in tropical Atlantic sea surface and air temperature. We propose that changes in North Atlantic high latitude climate are connected to regional hydroclimate, as evidenced by concurrent Caribbean precipitation and atmospheric methane variability, similar to Greenland D-O events. The broader implication of this study is that human activities may alter the fundamental relationship between Caribbean hydroclimate and greenhouse gases, which have likely sustained tropical wetlands and modulated methane production for millennia.

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