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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

Análise taxonômica, cladística e biogeográfica de Spelaeochernes Mahnert, 2001 (Arachnida, Pseudoscorpiones, Chernetidae) / Taxonomic, cladistic and biogeographical analysis of Spelaeochernes Mahnert, 2001 (Arachnida, Pseudoscorpiones, Chernetidae)

Schimonsky, Diego Monteiro von 06 November 2018 (has links)
Dentre as ordens de Arachnida, Pseudoscorpiones é a quarta mais diversa. Os organismos deste grupo se assemelham aos escorpiões superficialmente, porém não possuem uma cauda com agulhão e são bem menores, com tamanhos variando entre 0,5 mm a 1,0 cm. São animais relativamente comuns e com hábitos criptobióticos, podendo ser encontrados em diferentes habitats, inclusive cavernas. A família Chernetidae é a mais diversa com cerca de 690 espécies ao redor do globo e contém o gênero Spelaeochernes Mahnert, 2001, descrito com oito espécies para mais de 100 cavernas ao longo do território brasileiro. Foi realizada uma análise filogenética do gênero Spelaeochernes, bem como uma análise biogeográfica, além da elucidação sobre a obrigatoriedade deste gênero no ambiente subterrâneo. A partir do estudo morfológico, foi verificada a ocorrência de uma nova espécie para o gênero, com a descrição desta. Ainda, foram elencados caracteres contínuos, merísticos e caracteres discretos para a realização das análises filogenéticas. Estas foram realizadas com todas as espécies de Spelaeochernes (9), mais espécies de Epichernes Muchmore, 1982, Hesperochernes Chamberlin, 1924, Neochelanops Beier, 1964, Maxchernes Feio, 1960, Austrochernes Beier, 1932 e Tuberochernes Muchmore, 1997, todas Chernetidae, como grupo interno e duas espécies de Progarypus Beier, 1931 (Olpiidae), como grupo externo, totalizando 18 táxons terminais e 71 caracteres. Ainda, foi mapeada a distribuição de Spelaeochernes e, a partir da análise biogeográfica, verificou-se que algumas espécies compõem e reforçam áreas de endemismo já propostas, enquanto outras espécies, com distribuições mais amplas, podem representar espécies crípticas. Spelaeochernes não foi recuperado como monofilético, é um gênero com caracteres conservativos e faz-se necessário estudos morfológicos aprofundados, principalmente na anatomia interna e moleculares para delimitar espécies crípticas. Este gênero tem relação com Austrochernes da Australasia e Hesperochernes do Neártico, ambos com ocorrência no ambiente subterrâneo. Ainda Spelaeochernes pode representar um relicto gonduânico. Foi verificado que a ocorrência deste gênero é exclusiva do ambiente subterrâneo e, portanto, foi considerado aqui como troglóbio. Por fim, as espécies deste gênero já se encontram sob ameaça devido diferentes impactos (e.g. mineração, hidrelétricas, agronegócio, turismo), especialmente em áreas não protegidas legalmente, onde a maioria das cavernas brasileiras ocorre / Among the Arachnida order, Pseudoscorpiones is the fourth more diverse. These organisms resemble scorpions morphologically, but they don´t have a tail with a needle and they are much smaller in size, ranging from 0.5 mm to 1.0 cm. They are relatively common and they have cryptobiotic habits, being able to be found in different habitats, including caves. The Chernetidae family is the most diverse with about 690 species around the world, and contains the genus Spelaeochernes Mahnert, 2001, described with eight species for more than 100 caves along the Brazilian territory. A phylogenetic analysis of Spelaeochernes was carried out, as well as a biogeographical analysis, besides the elucidation about the mandatory occurrence of this genus in the subterranean environment. From the morphological study the occurrence of a new species for the genus was verified with subsequent description of it. Also, continuous, meristic characters and discrete characters were included in the phylogenetic analysis. These analyses were made with all species of Spelaeochernes (9), and other species of Epichernes Muchmore, 1982, Hesperochernes Chamberlin, 1924, Neochelanops Beier, 1964, Maxchernes Feio, 1960, Austrochernes Beier, 1932 e Tuberochernes Muchmore, 1997, all Chernetidae, as ingroup and two species of Progarypus Beier, 1931 (Olpiidae) as outgroup, with 18 terminal taxa and 71 characters. Furthermore, the distribution of this species was mapped and based on the biogeographical analysis. It was verified that some species compose and reinforce areas of endemism already proposed, while other species with wider distributions may represent cryptic species. Spelaeochernes was not recovered as monophyletic, it is a genus with conservative characters and molecular studies are necessary to delimit cryptic species. This genus is related to Austrochernes from Australasia and Hesperochernes from the Nearctic that also occur in the subterranean environment. Spelaeochernes may still represent a Gondwanan relict. It was verified that the occurrence of this genus is unique to the subterranean environment and, therefore, it was considered here as a troglobite. Finally, species of this genus are already under threat due to different impacts (e.g. mining, hydroelectric powerplants, agribusiness, tourism), especially in non-legally protected areas, where most Brazilian caves occur
202

Estudo da História Natural do Grilo Cavernícola Strinatia Brevipennis (Ensifera: Phalangopsidae) em Laboratório / Natural History of Cave Cricket Strinatia brevipennis (Ensifera: Phalangopsidae) in Laboratory

Franco, Flavia Pellegatti 13 February 1998 (has links)
Este estudo foi realizado em laboratório entre fevereiro de 1995 e dezembro de 1997. Os grilos (Strinatia brevipennis) foram coletados de diversas cavernas do Parque Estadual Intervales, no Vale do Ribeira, SP, e mantidos no porão do Edifício Ernesto Marcus, Departamento de Zoologia do IBUSP para estudo da história natural da espécie. Outra espécie de grilos (Endecous itatibensis) foi acompanhada devido a uma coleta acidental da mesma. As duas espécies foram mantidas separadamente, uma vez que a primeira não sobrevive em contato com a segunda. A reprodução de S. brevipennis ocorreu com sucesso em caixas de isopor, principalmente no verão. A reprodução de E. itatibensis, por outro lado, ocorreu apenas entre indivíduos mantidos livremente na câmara de criação, onde observou-se grande sucesso reprodutivo, com várias gerações e uma grande população proveniente de apenas uma fêmea. O período embrionário médio de S. brevipennis foi de 56 dias. O desenvolvimento pós-embrionário também foi acompanhado, onde observou-se provável variação no número de mudas (10 ou 11) antes de tornarem-se adultos. A identificação de macho e fêmea é facilmente observada nos três últimos instares ninfais e nos adultos através do surgimento do ovipositor (para ambas espécies) nas fêmeas, e das tégminas no último instar ninfal para S. brevipennis e no penúltimo para E. itatibensis nos machos. As fêmeas são ápteras nas duas espécies estudadas. A caracterização morfométrica mostra que os primeiros estágios da vida podem se confundir quanto às dimensões corporais para S. brevipennis. Nos últimos instares e adultos a caracterização torna-se mais facilitada através das medidas do comprimento do fêmur e da tíbia da perna III, e dos dimorfismos sexuais. / This study was conduced in laboratory between February 1995 and December 1997. The crickets (Strinatia brevipennis) have been collected in several caves from Parque Estadual Intervales, Ribeira Valley, São Paulo state. They were kapt in a room in the basement of Edifício Ernesto Marcus, Departamento de Aoologia IBUSP, to develop a study focusing their natural history. Another species of crickets (Endecous itatibensis) was studied due to an accidental collection. The two species were maintained in different compartments because the first did not survive whem in direct contact with the second. Reproduction of S. brevipennis was successful inside boxes, mainly during summer. Reproduction of E. itatibensis was only successful when animals were kept freely inside the compartment, where a large reproductive success for several generations was originated from a single female. S. brevipennis showed a mean period of embryonic development of 56 days. Post-embryonic development showed a variation of 10-11 molting events to achieve adulthood. Telling males from females is an easy task during the last three nymphal stages and among adults because of the development of ovipositor among females of both species; and development of mesothoracic wings during the last nymphal stage os S. brevipennis or the penultimate nymphal stage of E. itatibensis among males. Females are wingless in both species. Morphometric characterization showed that the first nymphal stages are hardly told from each other. Last stages and adults can be distinguished both from sexual dimorphisms and length of femur and tibia of leg III.
203

Nonpoint Agricultural Pollution in a Karst Aquifer: Lost River Groundwater Drainage Basin, Warren County, Kentucky

Tucker, Nancy 01 June 1982 (has links)
Chemical analysis of samples collected from subsurface streams and wells were analyzed to identify nonpoint pollutants in karst aquifers resulting from agricultural land use. Major flow paths and travel times taken by nonpoint pollutants were identified. A land use limitation map showing areas where agricultural activities may results in nonpoint pollution of the karst aquifer was prepared. A groundwater susceptibility map was prepared to show areas of the karst aquifer most susceptible to groundwater contamination by nonpoint pollution resulting from agricultural land use. Research findings revealed that pollutant concentrations may reach levels thousands of times greater during high discharge events than during baseflow conditions. Approximately thirty-five percent of the drainage basin was considered to have serve limitations for conventional agricultural land use. Fifty-eight percent had moderate limitations while only seven percent had slight limitations and were considered acceptable for conventional agricultural land use. Lineaments, fracture traces and sinkholes were plotted on a map to revel those areas to the karst aquifer that are susceptible to groundwater contamination as a result of agricultural activities. Recommendations for agricultural best management practices were made in terms of reducing the potential for contributing pollutants to the karst aquifer.
204

Abrigo Maximiano: uma análise sob a ótica da geoarqueologia / Maximiliano Rock Shelter: a geoarchaeological aproach

Alexandre José Felizardo 12 December 2017 (has links)
Sem Efeito. / Sem Efeito.
205

Middle stone age rose cottage cave lithic points: Does technological change imply change in hunting techniques?

Mohapi, Moleboheng 17 November 2006 (has links)
Faculty of Science School of Geography,Archaeology and Enviromental Studies 0310392a smami2003@yahoo.co.uk / Points are often the most abundant retouched lithics in MSA collections yet very little research has been done on their functions, especially in southern Africa where it has always been assumed that points were spears. This paper reports on the results of a technological analysis of two types of points from Rose Cottage Cave, South Africa. The study aims at examining the possibility that thick, broad points from various post-Howiesons Poort layers dating between 50 000 and 28 000 years ago were used as spearheads that were thrust at prey, while the narrow, thin points from one of the final MSA layers, Dc, (between 31 000 and 29 000 years old), were used as arrowheads that may have transported poison to prey. The results indicate that the former type of points were more likely to have been used as spearheads while the latter type were more likely to have been arrowheads.
206

Landmark Analysis of Musteloid Carnassials Applied to Taxonomic Identification and Examination of Sexual Dimorphism and Regional Morphotypes

Christine, Joel Alvin 15 August 2012 (has links)
Guy Wilson Cave (GWC) in Sullivan County, Tennessee holds many late Pleistocene mammal fossils. Based on visual morphology, several partial mandibles with lower carnassial from GWC appeared to be musteloids. Geometric morphometrics has been successfully used to identify fragmentary fossils, so a landmark based, 2 dimensional technique was applied to identify the GWC musteloids using the lower carnassial. Digital images of several GWC fossils and of extant reference musteloids were combined using morphometric programs tpsDIG1, tpsUtil, and tpsSuper. Statistical data analysis was performed in PASW Statistics. Results successfully separated Mephitis mephitis (striped skunk) from M. macroura (hooded skunk) and Martes americana (American marten) from M. pennanti (fisher). Sex-based and geographical patterns were also found in the data. Sex separated all three species via the lower carnassial. Geographic divisions were found for Mephitis mephitis, Martes americana and M. pennanti populations that hint at interestingly unique biogeographical histories for each taxon.
207

Description, Taphonomy, and Paleoecology of the Late Pleistocene Peccaries (Artiodactyla: Tayassuidae) from Bat Cave, Pulaski County, Missouri

Woodruff, Aaron L 01 May 2016 (has links)
The late Pleistocene faunal assemblage from Bat Cave, central Ozarks, Missouri provides an opportunity to assess specific aspects of behavior, ecology, and ontogeny of the extinct peccary Platygonus compressus. All identifiable elements referable to this taxon were catalogued and examined, and a minimum number of individuals of 70 was determined for the sample. The presence of distinct, non-overlapping age groups suggests that P. compressus utilized Bat Cave on a seasonal basis. A predator-prey relationship with Canis dirus, the second most abundant vertebrate from the Bat Cave site, is also described in this study. Damage patterns suggest that the feeding patterns of C. dirus at Bat Cave were consistent with its extant relative, and that these predators would periodically enter the cave to hunt and/or scavenge peccaries. Overall, the fossil material from Bat Cave is virtually unweathered and represents one of the most extensive and well-preserved late Pleistocene faunas from the Ozarks.
208

Impact of Urban Stormwater Runoff on the Water Quality of the Subsurface Lost River, Bowling Green, Kentucky

Rice, Donald 01 July 1982 (has links)
Bowling Green, Kentucky is located in a distinctive karst region, characterized by subsurface drainage. The Lost River is a large subsurface stream which flows beneath the city. It receives much of the stormwater runoff from Bowling Green, since most of the city's runoff is directed underground. Significant pollutants in Bowling Green's stormwater runoff were identified from water quality test results of storm event grab samples, and a composite sample, of runoff entering the urban By-Pass Cave. Water quality test results were also obtained from storm event grab samples, and a composite sample, of the Lost River at the Blue Hole before it reached Bowling Green and at the Resurgence after it had passed beneath Bowling Green. Significant pollutant test results from the Blue Hole and Resurgence were analyzed to determine the impact of urban stormwater runoff on the water quality of the Lost River. Suspended solids were the only urban runoff pollutant identified as entering the Lost River in significant quantities. Animal waste, iron, and oil and grease were identified as stormwater runoff pollutants of the Lost River, but whose origin, either urban or rural, could not be conclusively determined from the available data.
209

Where Did They Go? Analysis of Out-Migration from Mammoth Cave National Park, 1920-1940

Eke, Collins U. 01 April 2019 (has links)
The 52,830-acre Mammoth Cave National Park, located in the karst region of south-central Kentucky, was formally established in July of 1941, culminating nearly three decades of park creation that displaced several thousand residents of the region. This thesis sampled residents using the 1920 manuscript census for the United States Census of Population and Housing and tracked their migration destinations using the 1930 and 1940 manuscript censuses. Migration patterns for the entire sample, as well as by race and homeownership status, were identified through mapping. Out-migrants generally chose locations north, west, and east of the proposed park area, noticeably neglecting the Deep South. Statistical analyses proved significant differences between proportions of Black out-migrants and White out-migrants moving to urban areas, as well as those of homeowners and renters who were not successfully tracked during analysis. The research underlines unintended consequences of the forced out-migration from the proposed Mammoth Cave National Park and several factors that contributed to it. In the process, the thesis fills a gap in research on Mammoth Cave National Park and sheds light on an important aspect of Kentucky’s history.
210

Caractérisation multi-échelle du milieu karstique non saturé. / Multi-scale caracterization of the unsaturated karst medium.

Verdet, Cecile 01 April 2019 (has links)
Le milieu karstique, et tout particulièrement sa partie superficielle, est caractérisé par une altération importante responsable sur le site de Lascaux de formations calcaires en plaquettes mais aussi de dissolutions importantes pouvant laisser place à des sables, argiles, etc. La présence de grottes ornées dans ce milieu nécessite la caractérisation du milieu environnant afin de protéger les grottes et contribuer à la conservation des œuvres pariétales. Cette thèse porte sur la caractérisation du milieu karstique à plusieurs échelles au moyen de deux méthodes : la géophysique avec la Tomographie de Résistivité Electrique (TRE), et la caractérisation pétrophysique, à l’échelle du laboratoire, avec la microscopie, la porosimétrie au mercure et des mesures électriques sur échantillons. A l’échelle du massif, nous avons caractérisé l’amont hydraulique de la grotte de Lascaux par un suivi temporel par TRE durant 6 ans et par trois modélisations géostatistique 3D, à trois dates. Le suivi temporel a permis de comprendre le fonctionnement hydrogéologique du site. Le couplage du suivi temporel avec le 3D complété par les mesures sur échantillons a en outre permis de comprendre le fonctionnement d’un drain situé dans l’épikarst susceptible d’alimenter l’émergence à l’entrée de la grotte de Lascaux. La modélisation 3D a aussi permis d’identifier un escarpement du promontoire calcaire au nord-est de la grotte de Lascaux qui laisse place à des formations argilo-sableuse. A l’échelle de la paroi et en lien avec des recherches menées sur la grotte Chauvet-Pont d’Arc, un dispositif original de micro-TRE a été mis en place à la paroi dans une carrière souterraine, permettant une mesure de TRE à une échelle submétrique et une résolution centimétrique. A cette résolution apparaît un effet d’électrode que nous corrigeons lors de l’inversion des données de TRE par l’utilisation d’une Electrode Equivalente Ponctuelle (EEP) placée à une profondeur caractéristique. La paroi étudiée a été soumise à des feux. On montre par un suivi TRE sur plusieurs mois et des analyses pétrophysiques complémentaires que les feux impactent de façon tangible les premiers centimètres de la paroi dont la porosité et la connectivité sont modifiées. On montre en outre que des variations saisonnières de saturation sont mises en évidence à cette petite échelle. Ce dispositif pourrait être appliqué au site de Lascaux pour, à terme, mesurer et prédire les arrivées d’eau à la paroi, en lien ou pas avec la circulation modélisée à l’échelle du massif. Une telle démarche pourrait devenir un outil de conservation de parois rocheuses support d’œuvres pariétales. / The karst environment and especially its superficial part is typified by an important alteration. At the Lascaux site, alteration is responsible for plate limestone and also detrital clayey-sands soils due to dissolution of limestones. The presence of painted caves in this altered environment raises the need to characterize the karst environment in order to protect the caves and contribute to mural paintings conservation. The aim of this PhD thesis is to characterize the karst environment at different scales using two main methods: (1) geophysics and in particular Electrical Resistivity Tomography (ERT) and (2), petrophysics at the Lab scale, including microscopy, mercury porosimetry and electrical measurements. At the field scale, we characterized the calcareous surroundings of the Lascaux cave relying on a 6 years-long time-lapse monitoring by ERT complemented by geostatistical 3D reconstructions of the resistivity values. The time-lapse monitoring permitted a better understanding of the hydrogeology of the site. Combining ERT time-lapse monitoring, 3D models of the resistivity distribution and additional measurements on samples allowed to identify a drain within the epikarst, which is most likely responsible for the emergence of water at the Lascaux cave entrance. The 3D modelling of the resistivity values also allowed to identify a scarp of unaltered limestones, northeast of the Lascaux cave, leaving room for clayey-sand detrital formations. In relation to a current research program on the Chauvet-Pont d’Arc cave, an original micro-ERT acquisition layout was fitted on the wall of an underground quarry, allowing measurements at a sub-metric scale with a centimetric resolution. At such a fine resolution, an unwanted electrode effect appeared. We remedied this electrode effect by inverting ERT data with an Equivalent Electrode Point (EEP) buried in the ground at a characteristic depth. The quarry wall was subjected to fires. Relying on a micro-ERT time-lapse monitoring during few months complemented by petrophysical analyses, we showed that the fires impacted the first centimeters of the quarry wall whose porosity and connectivity were modified. We also showed that seasonal water saturation variations could be detected at such a small scale. Thus, this small scale acquisition layout may ultimately be used at Lascaux to measure and predict water intakes directly at the cave walls in relation, or not, with the water flow modelled at the field scale. Such an approach may become a new tool for the conservation of painted cave walls.

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