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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.
41

Archaeological explorations in caves of the Point of Pines Region

Gifford, James C. January 1957 (has links)
No description available.
42

Human skeletal remains of the ancient Maya in the caves of Dos Pilas, Guatemala

Minjares, Amador, Jr. 30 September 2004 (has links)
This study focuses on the assessment of the depositional activity that occurred in six caves of the Petexbatun region of the Peten, Guatemala through a quantitative analysis of the human skeletal material recovered from them. Five of these caves are associated with the site of Dos Pilas; the sixth cave (Cueva de Los Quetzales) is located beneath the site of Las Pacayas. The cave is an important aspect of the Maya worldview, as evidenced in the artifactual and skeletal material found in caves by archaeological exploration. My study is specifically focused on the assessment of the primary and/or secondary burial of Maya dead within these caves via analyses of the relative skeletal element frequencies, the minimum and probable number of individuals, and the identification of human cut marks. Based on these lines of evidence and data from preliminary reports, between 100 and 150 individuals of both sexes and various age groups were primarily deposited/buried in these caves. Secondary activity may be inferred based on evidence of human-made cut marks on several elements. There is no osteological evidence to support the hypothesis of human sacrifice. I was unable to determine the status of the individuals deposited in the caves. The best interpretation is that several types of depositional activity occurred within these caves over time.
43

Ecology and Hydrology of a Threatened Groundwater-Dependent Ecosystem:The Jewel Cave Karst System in Western Australia

Stefan@calm.wa.gov.au, Stefan Eberhard January 2004 (has links)
Groundwater is a significant component of the world's water balance and accounts for >90 % of usable freshwater. Around the world groundwater is an important source of water for major cities, towns, industries, agriculture and forestry. Groundwater plays a role in the ecological processes and 'health' of many surface ecosystems, and is the critical habitat for subterranean aquatic animals (stygofauna). Over-abstraction or contamination of groundwater resources may imperil the survival of stygofauna and other groundwater-dependent ecosystems (GDEs). In two karst areas in Western Australia (Yanchep and Leeuwin-Naturaliste Ridge), rich stygofauna communities occur in cave waters containing submerged tree roots. These aquatic root mat communities were listed as critically endangered because of declining groundwater levels, presumably caused by lower rainfall, groundwater abstraction, and/or forest plantations. Investigation of the hydrology and ecology of the cave systems was considered essential for the conservation and recovery of these threatened ecological communities (TECs). This thesis investigated the hydrology and ecology of one of the TECs, located in the Jewel Cave karst system in the Leeuwin-Naturaliste Ridge. A multi-disciplinary approach was used to explore aspects pertinent to the hydrology and ecology of the groundwater system. Thermoluminescence dating of the limestone suggested that development of the karst system dates from the Early Pleistocene and that caves have been available for colonisation by groundwater fauna since that time. Speleogenesis of the watertable maze caves occurred in a flank margin setting during earlier periods of wetter climate and/or elevated base levels. Field mapping and leveling were used to determine hydrologic relationships between caves and the boundaries of the karst aquifer. Monitoring of groundwater levels was undertaken to characterise the conditions of recharge, storage, flow and discharge. A hydrogeologic model of the karst system was developed. The groundwater hydrograph for the last 50 years was reconstructed from old photographs and records whilst radiometric dating and leveling of stratigraphic horizons enabled reconstruction of a history of watertable fluctuations spanning the Holocene to Late Pleistocene. The watertable fluctuations over the previous 50 years did not exceed the range of fluctuations experienced in the Quaternary history, including a period 11,000 to 13,000 years ago when the watertable was lower than the present level. The recent groundwater decline in Jewel Cave was not reflected in the annual rainfall trend, which was above average during the period (1 976 to 1988) when the major drop in water levels occurred. Groundwater abstraction and tree plantations in nearby catchments have not contributed to the groundwater decline as previously suggested. The period of major watertable decline coincided with a substantial reduction in fire frequency within the karst catchment. The resultant increase in understorey vegetation and ground litter may have contributed to a reduction in groundwater recharge, through increased evapotranspiration and interception of rainfall. To better understand the relationships between rainfall, vegetation and fire and their effects on groundwater recharge, an experiment is proposed that involves a prescribed burn of the cave catchment with before-after monitoring of rainfall, leaf-area, ground litter, soil moisture, vadose infiltration and groundwater levels. Molecular genetic techniques (allozyrne electrophoresis and mitochondria1 DNA) were used to assess the species and population boundaries of two genera and species of cave dwelling Amphipoda. Populations of both species were largely panrnictic which was consistent with the hydrogeologic model. The molecular data supported the conclusion that both species of amphipod have survived lower watertable levels experienced in the caves during the Late Pleistocene. A mechanism for the colonization and isolation of populations in caves is proposed. Multi Dimensional Scaling was used to investigate patterns in groundwater biodiversity including species diversity, species assemblages, habitat associations and biogeography. Faunal patterns were related to abiotic environmental parameters. Investigation of hydrochemistry and water quality characterized the ecological water requirements (EWR) of the TEC and established a baseline against which to evaluate potential impacts such as groundwater pollution. The conservation status of the listed TEC was significantly improved by increasing the number of known occurrences and distribution range of the community (from 10 m2 to > 2 x lo6 m2), and by showing that earlier perceived threatening processes (rainfall decline, groundwater pumping, tree plantations) were either ameliorated or inoperative within this catchment. The GDE in the Jewel Cave karst system may not have been endangered by the major phase of watertable decline experienced 1975-1987, or by the relatively stable level experienced up until 2000. However, if the present trend of declining rainfall in southwest Wester,,Australia continues, and the cave watertable declines > 0.5 m below the present level, then the GDE may become more vulnerable to extinction. The occurrence and distribution of aquatic root mat communities and related groundwater fauna in other karst catchments in the Leeuwin-Naturaliste Ridge is substantially greater than previously thought, however some of these are predicted to be threatened by groundwater pumping and pollution associated with increasing urban and rural developments. The taxonomy of most stygofauna taxa and the distribution of root mat communities is too poorly known to enable proper assessment of their conservation requirements. A regional-scale survey of stygofauna in southwest Western Australia is required to address this problem. In the interim, conservation actions for the listed TECs need to be focused at the most appropriate spatial scale, which is the karst drainage system and catchment area. Conservation of GDEs in Western Australia will benefit fi-om understanding and integration with abiotic groundwater system processes, especially hydrogeologic and geomorphic processes.
44

Art, religion and politics Dunhuang Cave 220 /

Ning, Qiang. January 1997 (has links)
Thesis (Ph. D.)--Harvard University, 1997. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (p. 323-347).
45

Mogao Cave 254 a case study in early Chinese Buddhist art /

Abe, Stanley Kenji. January 1989 (has links)
Thesis (Ph. D.)--University of California, Berkeley, 1989. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (p. 160-175).
46

The Transvaal ape-man-bearing cave deposits.

Brain, C. K. January 1958 (has links)
Thesis--University of Cape Town. / Includes bibliographical references.
47

A GIS predictive model of prehistoric rockshelter selection in the Bighorn Mountains of Wyoming

Davey, Amanda M. January 2009 (has links)
Thesis (M.A.)--University of Wyoming, 2009. / Title from PDF title page (viewed on July 2, 2010). Includes bibliographical references (p. 94-105).
48

Análise da diversidade funcional e dos padrões de riqueza de aranhas cavernícolas do Brasil e um modelo de mapeamento / Analysis of functional diversity and richness patterns of cave spiders from Brazil and a mapping model

Igor Cizauskas 14 November 2017 (has links)
Um dos principais desafios no estudo da biodiversidade é o mapeamento de grupos faunísticos megadiversos. O mapeamento da biodiversidade auxilia na avaliação dos padrões de distribuição e riqueza de espécies e de suas comunidades, na compreensão de características ambientais e, consequentemente, dos fatores ecológicos por trás da especialização das espécies ao meio. Nesse trabalho foi avaliada a diversidade de aranhas (Araneae) coletadas em cavernas do Brasil, com o objetivo de determinar e classificar a araneofauna de cavernas. Um banco de dados composto por 29261 aranhas adultas oriundos de 3455 cavernas do Brasil foi elaborado. Foram determinadas 179 espécies nomeadas e 428 morfoespécies, totalizando 607 espécies, distribuídas em 59 famílias. Apresentamos os dados históricos dos estudos bioespeleológicos no Brasil com ênfase em aranhas entre 1972-2015, uma nova listagem das espécies nominadas e o mapeamento da distribuição dessas espécies, sendo este disponível para consulta em uma ferramenta virtual, o AppBio. Foi avaliada a diversidade funcional das espécies determinadas com base nos comportamentos de forrageamento conhecidos para as aranhas. Uma análise de guildas foi elaborada e as espécies foram classificadas ecológico-evolutiva em grupos funcionais, determinados pelo grau de relação das populações-fonte com o ambiente cavernícola (acidental, trogloxeno, troglófilo e troglóbio), categorias clássicas propostas por Schiner-Racovitza para as espécies subterrâneas. Características morfológicas que indicam preferência pelo ambiente hipógeo (ex. anoftalmia e despigmentação corporal) e especialização à vida no ambiente subterrâneo também foram avaliadas. Os padrões de riqueza tanto dos grupos funcionais como macroecológicos (ex. latitude e altitude) foram avaliados e discutidos de forma sucinta. A riqueza regional também foi avaliada sendo agrupada pela ocorrência das espécies em cavernas de diferentes Biomas brasileiros. Uma boa base de dados e um modelo de mapeamento e disponibilização desses dados de forma virtual foram elaborados para auxiliar nos estudos da fauna de aranhas cavernícolas e para definir propostas para preservação da fauna e conservação dos ambientes subterrâneos / One of the main challenges in the study of biodiversity is the mapping of megadiverse faunal groups. Biodiversity mapping assists in assessing patterns of distribution and species richness and their communities, understanding environmental characteristics and, consequently, ecological factors behind the species\' specialization to the environment. This work evaluated the diversity of spiders (Araneae) collected in caves in Brazil, with the objective of determining and classifying the araneofauna of caves. A database consisting of 29261 adult spiders from 3455 caves in Brazil was prepared. There were 179 named species and 428 morphospecies, totaling 607 species, distributed in 59 families. We present the historical data of the biospeleological studies in Brazil with a spider focus between 1972-2015, a new listing of the nominated species and the mapping of the species distribution, being available for consultation in a virtual tool, AppBio. It was evaluated the functional diversity of the determined species based on the known foraging behaviors for the spiders. An analysis of guilds was elaborated and the species were classified ecologically-evolutionary in functional groups, determined by the degrees of relation of the source populations with the cave environment (accidental, trogloxene, troglophile and troglobite), classical categories proposed by Schiner-Racovitza for subterranean species. Morphological characteristics indicating preference for the hypogeum environment (eg. anophthalmia and body depigmentation) and specialization in life in the underground environment were also evaluated. The richness patterns of both the functional and macroecological groups (eg. latitude and altitude) were evaluated and discussed succinctly. The regional richness was also evaluated by separating by the occurrence of the species in caves of different Brazilian Biomes. A good database and a model for mapping and making this data available in a virtual way were developed to assist in the study of cave spider fauna and to define proposals for preserving fauna and conserving underground environments
49

Chrotopterus auritus (Peters, 1856) (Chiroptera, Phyllostomidae): First Record for the State of Rio Grande Do Norte, Northeastern Brazil

Basílio, Gustavo Henrique Nunes, de Araujo, Jan Pierre Martins, Mena, Juan Carlos Vargas, da Rocha, Patrício A., Kramer, Marcelo Augusto Freitas 07 May 2017 (has links)
Chrotopterus auritus is a phyllostomid bat with a wide distribution in the Neotropics. It has been recorded in Brazil’s 6 biomes but with few records in the Caatinga. We provide the first record of C. auritus for Rio Grande do Norte state, northeastern Brazil, based on records from 2 caves, Três Inchu and Gruta da Carrapateira. The nearest records are ca. 400 km southeast in Ceará state and ca. 350 km northwest in Pernambuco state. Our new records fill the northeastern distributional gap of C. auritus in Brazil and South America.
50

Muknalia minima from the Yucatán of Mexico is Synonymous with the Collared Peccary, Pecari Tajacu (Artiodactyla: Tayassuidae)

ob, Blaine W., Samuels, Joshua X., Chatters, James C., Arroyo-Cabrales, Joaquin 01 January 2020 (has links)
Ongoing investigation of peccary remains from fossiliferous deposits in the Yucatán resulted in re-examination of previously identified tayassuid fossils from the region. This included the recently described new genus and species of peccary, Muknalia minima, which is based on a dentary from Muknal Cave near Tulum, Quintana Roo, Mexico. Diagnostic characters of this taxon include a concave notch along the caudal edge of the ascending ramus and a ventrally directed angular process. Our assessment of the holotype indicates that these characteristics are not a reflection of the original morphology, but are instead the result of breakage and polishing of the posterior aspect of the dentary. Measurements and intact morphological features indicate the Muknal Cave specimen belongs to the extant collared peccary, Pecari tajacu.

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