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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.
21

Características hidrogeoquímicas da bacia de drenagem do rio Sorocaba, SP: processos erosivos mecânicos e químicos / Hydrogeochemical characteristics of the Sorocaba River basin drainage, SP: mechanical and chemical erosion processes

Alexandre Martins Fernandes 08 August 2012 (has links)
A caracterização hidrogeoquímica da bacia do rio Sorocaba foi realizada a partir do estudo detalhado das cargas fluviais particulada e dissolvida, considerando a dinâmica dos transportes das principais espécies químicas, bem como os aportes atmosféricos e antrópicos, identificando os processos erosivos mecânicos e químicos predominantes na bacia de drenagem. A caracterização hidrológica permitiu identificar os principais mecanismos de recarga e descarga na bacia de drenagem e determinar o escoamento superficial rápido, revelando os períodos de maior potencial erosivo nos últimos 20 anos. O estudo da dinâmica da carga fluvial particulada mostrou a ocorrência de processos de remobilização e sedimentação ao longo da bacia, permitindo verificar um aumento do transporte fluvial específico em 2,5 vezes das nascentes até a foz. A erosão mecânica, calculada com base no transporte de sedimentos finos em suspensão junto à foz do rio Sorocaba, foi de 55,70 t km-2 a-1, indicando uma taxa de degradação física de 37,88 m Ma-1. A origem da matéria orgânica na carga particulada fluvial se mostrou associada aos efluentes domésticos após caracterização isotópica do 13C. O comportamento hidroquímico fluvial evidenciou uma diferença de predomínio de espécies químicas dissolvidas entre as cinco estações de amostragem, permitindo verificar a influência dos processos de diluição fluvial, de acordo com as relações concentração x vazão. O modelo geoquímico utilizado permitiu estimar o CO2 atmosférico/solo consumido durante o processo de alteração de rochas na bacia de drenagem em 198 x 103 moles km-2 a-1, dos quais 98% foi relacionado à alteração de silicatos. O modelo de reconstituição desse consumo nos últimos 59 anos mostrou-se pouco variável, entretanto o modelo associado exclusivamente aos silicatos indicou um aumento no mesmo período, a uma taxa de 2,7 x103 moles km-2 a-1. Comparada com a erosão mecânica, a erosão química se mostrou inferior em cerca de 2,5 vezes, enquanto que, ainda em termos de erosão química, as taxas de alteração de silicatos e carbonatos na bacia de drenagem foram de 9,4 e 5,3 m Ma-1, respectivamente. O índice de alteração de rocha RE, determinado a partir dos dados geoquímicos das águas fluviais, indicou a mudança de um possível domínio de estabilidade da caulinita para o das argilas 2:1, evidenciando a ocorrência do processo de bisialitização / The hydrogeochemical characterization of the Sorocaba River basin was performed from the detailed study of particulate and dissolved river loads. Considering the main chemical species transported, as well as the atmospheric and anthropogenic inputs, it ws identified the mechanical and chemical erosion processes prevailing in the drainage basin. The hydrologic characterization identified the main mechanisms of recharge and discharge in the drainage basin, and allowed to determine the quickly surface runoff, showing periods of increased erosion potential in the last 20 years. The study of the particulate load dynamics demonstrated the occurrence of sedimentation and remobilization processes in the basin, allowing to verify a specific fluvial transport increased by 2.5 times from headwaters to the mouth of the Sorocaba River. The mechanical erosion, calculated based on the fine suspended sediments transported at the mouth of the Sorocaba River, was 55.70 t km-2 yr-1, indicating a physical degradation rate of 37.88 m Myr-1. The origin of organic matter present in the particulate load was associated to domestic sewage, after isotopic characterization of the 13C. The fluvial hydrochemical performance revealed the predominance of different dissolved chemical species between the five sampling stations, enabling to verify the influence of fluvial dilution processes, according to the concentration-discharge relationships. The geochemical model used allowed us to estimate CO2 atmospheric / soil consumed during the alteration rocks process in the drainage basin of 198 x 103 mol-1 km2 yr-1, which 98% was related to silicates alteration. The reconstitution model of this consumption in the last 59 years has shown to be little variable, however the model exclusively associated with silicates demonstrated an increase during same period, in a rate of 2.7 x 103 moles km-2 yr-1. Compared to mechanical erosion, the chemical erosion was inferior to about 2.5 times, whereas, also in terms of chemical erosion, the silicate and carbonate alterations rates in the drainage basin were 9.4 and 5.3 m Myr-1, respectively. The rock alteration index RE, determined from the geochemical data, indicated a possible change in the kaolinite stability domain to the clays 2:1, indicating the occurrence of the bisialitization process
22

Avaliação do modelo digital de elevação Aster para analise morfometrica de bacias hidrograficas / Evaluation of ASTER digital elevation model for morphometric analysis of drainage basins

Jesus, Nilton de 14 August 2018 (has links)
Orientador: Marcos Cesar Ferreira / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Geociencias / Made available in DSpace on 2018-08-14T14:48:41Z (GMT). No. of bitstreams: 1 Jesus_Niltonde_D.pdf: 15378244 bytes, checksum: 3da945d16f0c7c0709889469e6205293 (MD5) Previous issue date: 2009 / Resumo: Nos últimos anos, as aplicações da tecnologia SIG têm contribuído às pesquisas geomorfológicas com uma série de novas possibilidades para quantificação das formas de relevo. Ênfase particular tem sido dada à extração de parâmetros morfométricos de bacias hidrográficas, a partir de Modelos Digitais de Elevação (MDE). As aplicações da tecnologia SIG vêm se tornando importante ferramenta para modelagem de processos geomorfodinâmicos, a partir destes parâmetros quantitativos. Neste contexto, a presente pesquisa tem como objetivo apresentar um procedimento para extração da rede de drenagem e dos divisores de bacias hidrográficas, de modo automatizado, a partir do modelo digital de elevação de imagens estereoscópicas do sensor óptico orbital ASTER. Com estes resultados foi calculado parâmetros morfométricos para comparar com parâmetros morfométricos calculados de forma analógica a partir de cartas topográficas do IBGE na escala de 1:50.000. A metodologia utiliza trabalhos no campo da geomorfometria com destaque para a adoção do algoritmo Dinf na definição da rede e de bacias hidrográficas apoiado pelo SIG MapWindow versão 4.4 com plug-in TauDEM (software livre) e pelo SIG Idrisi 32 no cálculo e comparação dos parâmetros morfométricos. Os resultados mostraram que é possível a extração da rede de drenagem e das bacias hidrográficas a partir dos dados do MDE ASTER sem a perda da qualidade para os parâmetros morfométricos tais como, o Índice de Circularidade, Declividade Média, Freqüência de Canais de Primeira Ordem e Fator Topográfico. / Abstract: In the last years, the applications of the Geographical Information System (GIS) technology have been contributing for the geomorphologic researches bringing several new possibilities for quantification landform surface. A particular emphasis has been to the extraction morphometric parameters in watershed supported by Digital Elevation Models (DEM). The applications of the technologies GIS are becoming an important tool for modelling geomorphodinamics processes, based on quantified parameters. In this context, the research focus on the extraction of automated drainage networks and watersheds with DEM from stereoscopic images of the optical sensor orbital ASTER, in order to compare and calculate morphometric parameters with DEM from topographic maps of IBGE, in scale of 1:50.000. This method is based in the field of the geomorphometric with prominence for the adoption of the algorithm Dinf in the determination of drainage network and watershed by GIS MapWindow version 4.4 and plug-in TauDEM (free software) and by GIS Idrisi 32 in the calculation and comparison of the morphometric parameters. It was verified that ASTER DEM extraction morphometric is possible without losing quality for the morphometric parameters as the Circularity Ratio, Medium Slope for watershed, Frequency of First Order Stream and Topography Factor. / Doutorado / Análise Ambiental e Dinâmica Territorial / Doutor em Ciências
23

Using GIS and LiDAR DTMs to Characterize Terrain Features associated with Gopher Tortoise (Gopherus Polyphemus) Burrows

Mosley, Robert Luke 14 August 2015 (has links)
Limited knowledge exists of the terrain variables that have an influence on gopher tortoise (Gopherus polyphemus) burrow locations. Previous studies suggest that terrain features may play a role in preference of burrow location. LiDAR- (Light Detection and Ranging) derived terrain features can be evaluated through GIS (Geographic Information System) analysis at a fine spatial scale. LiDAR data acquired at 0.5 meter post spacing over three locations on Camp Shelby Joint Forces Training Center, MS were used to develop DTMs (Digital Terrain Models) for use in burrow site characterization. Terrain variables (e.g. elevation, slope, aspect) were developed from the LiDAR DTM in ArcGIS. Burrows and randomly allocated non-burrow points were used in logistic regression analysis to model the relationship between burrow occurrence and terrain features. Four models correctly classified more than 83% of the burrow locations. The R2 were 34.83%, 49.31%, 28.09%, and 31.51%.
24

Aspects of Cyclic Sedimentation in the Upper Mississippian, Mauch Chunk Group, southern West Virginia and southwest Virginia

Buller, Ty Bradford 27 May 2014 (has links)
Late Mississippian, Mauch Chunk Group strata constitute a westward-thinning clastic wedge of strata up to 1000m thick that developed in the Central Appalachian Basin over a ~ 7 million year time interval. Included within the Mauch Chunk Group are multiple incised-valley fills and a distinctive prodeltaic succession of laminated sandstones and mudstones. Calculated estimates of drainage basin areas for incised-valley fills in the Mauch Chunk Group range from > 1,000,000 km2 for the Stony Gap Sandstone to < 100,000 km2 for the Princeton Formation. Drainage area estimates are consistent with detrital zircon geochronology and petrographic data and suggest that the Stony Gap and Ravencliff incised-valley fills were derived from distal, northern and northwestern cratonic sources that dispersed sediment into NE-SW-oriented, longitudinal incised-valley drainages and that the Princeton Formation was derived from proximal tectonic highland sources along the eastern margin of the Appalachian Basin which dispersed sediment into a transverse incised-valley. The Pride Shale overlies the Princeton incised valley fill and records a hierarchy of tidal periodicities is preserved in the Pride Shale. Microlaminated, semi-diurnal sandstone-siltstone/shale couplets record the dominant ebb tide of the day. Up to 17 semi-diurnal couplets are stacked into neap-spring (fortnightly) tidal cycles. Neap-spring cycles are arranged in thickening and thinning that record seasonal cycles driven by the annual monsoon. Total organic carbon (TOC) values are a proxy for annual climatic cycles. TOC contents are higher within intermonsoonal and lower within monsoonal components of annual cycles reflecting, respectively, lesser and greater dilution by terrestrial flux. / Master of Science
25

Hydrological and Geomorphological Observations on a High Latitude Drainage Basin: "Jason's Creek", Devon Island, N.W.T.

Cogley, John Graham 05 1900 (has links)
<p> "Jason's Creek" is a stream draining 2.2 km^2 of arctic limestone terrain. Its annual regime consists of a ten-month period in which it is frozen to its bed, a short spring flood which occurs shortly after tenperatures cross the freezing-point in late June, and a period of about two months during which discharge is relatively low and fluctuates diurnally in response to inputs of radiative and heat energy to the snowpack. In 1970, the spring flood occupied the first two weeks of July and effected the discharge of some nine-tenths of total annual runoff. Tne low flow period was punctuated by rainstorms which generated sharply-defined floods: basin response was rapid and efficient, for storm runoff is facilitated over the unvegetated ground and through the shallow active layer above the permafrost table. Covariance and spectral analyses suggest a basin lag time of five hours, both for low discharges of snowmelt water and flood discharge of rainwater. It appears, from the spectra of the time series, that radiation is a better index of snowmelt discharge than is temperature.</p> <p> Most of the annual removal of sediment from the basin takes place during the spring flood, when the stream is turbid and movement of channel bed material is vigorous, In the longer period after the flood the main component of stream load is the solute load. The concentration of dissolved material varies inversely while suspended sediment concentration varies directly with discharge. Solute concentrations are lower than those commonly found in limestone streams at lower latitudes, suggesting that in "Jason's Creek" the increased solubility of CO2 at low temperatures is more than counteracted by a decrease in the rate of solution of CaCO3. There are also indications that the concentration of CO2 in snowmelt water 2 may be smaller, in absolute terms, than in rainwater.</p> <p> The role of water is crucial in many processes acting on slopes and delivering detritus to stream channels; rills, for example, remove ions in solution and fine particles in suspension, notably from the base of talus slopes, and lubrication of the active layer after rainstorms generates bowl-slide and mudflow activity.</p> / Thesis / Master of Science (MSc)
26

Análise temporal do uso e ocupação do solo da microbacia hidrográfica do córrego do Itaperu/Itapocu, no município de Piracicaba / Temporal analysis of soil use and occupation of Itaperu/Itapocu stream watershed in the municipality of Piracicaba

Batagin, Bruna 10 July 2017 (has links)
O presente trabalho foi desenvolvido com o objetivo de analisar, por meio da técnica de fotointerpretação, o uso e ocupação do solo na microbacia hidrográfica do córrego do Itaperu/Itapocu, no município de Piracicaba (SP), do período de 1940 até 2016. Foram utilizadas fotografias aéreas dos anos de 1940, 1978, 2000 e 2005 e imagens dos satélites Rapid Eye e Cbers 4 dos anos de 2011 e 2016. Para tanto, o estudo foi dividido em três etapas que consistiram em primeiro analisar o uso e ocupação do solo na microbacia hidrográfica em todo sua extensão; na sequência foi analisada a evolução de áreas urbanas na microbacia e por último foram verificadas as Áreas de Preservação Permanente. Como resultado da primeira etapa foi identificada uma grande mudança da ocupação dos usos do solo ao longo das décadas estudadas. Na segunda etapa, foi constatado o avanço urbano para a área da microbacia hidrográfica que era totalmente rural e ao longo dos anos passou a ser incorporada no perímetro urbano. Na última etapa ao analisar as Áreas de Preservação Permanente, com o crescimento urbano ocorrido no local, houve a extinção de cinco nascentes e alguns cursos d\'água tiveram seu comprimento reduzido. / The present work was developed with the purpose to analyze, by the photointerpretation technique, the use and occupation of the soil in the watershed of the Itaperu/Itapocu stream in the municipality of Piracicaba (SP), between 1940 and 2016. Aerial photographs from the years 1940, 1978, 2000 and 2005 were used, as well as satellite images of Rapid Eye and Cbers 4 from 2011 and 2016. The study was divided into three steps. First, the use and occupation of the soil in the watershed drainage basin in all its extension were analyzed. Next, the evolution of urban areas in the watershed were investigated. Finally, the Permanent Preservation Areas were studied. In the first stage, it was identified a major shift of the occupation of soil uses over the decades studied. In the second, it was found the urban advance into the hydrographic watershed area, which used to be entirely rural and, over the years, became incorporated into the urban area. In the last step, there was the extinction of five springs and some watercourses had their lengths reduced due to urban growth in the area.
27

Os recrutamentos militares e as relações sociedade-Estado na Capitania/Província de São Paulo (1765-1828)

Silva, Karina da [UNESP] 21 March 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-03-21Bitstream added on 2014-06-13T19:25:45Z : No. of bitstreams: 1 silva_k_me_fran.pdf: 726758 bytes, checksum: c4e24ce2489fb6fb6f6cd0df2b13ce9f (MD5) / Os recrutamentos militares foram uma realidade na Capitania de São Paulo, desde o século XVIII. Os conflitos na Bacia do Prata, na busca de delimitar as fronteiras da América portuguesa e espanhola, exigiram a organização de uma estrutura militar no Brasil. Para sediar essa estrutura foi escolhida a referida Capitania. A união de interesses, de segmentos da elite paulista e da Coroa portuguesa, possibilitou a consolidação da militarização da Capitania ao longo da segunda metade do século XVIII. Todavia, a dinamização da economia e da sociedade paulista, a partir das últimas décadas do século XVIII e início do XIX, entrou em conflito com a militarização ali desenvolvida. O presente trabalho buscou analisar as diferenças entre os recrutamentos realizados em São Paulo nesses dois momentos, focando as relações entre a sociedade e o Estado na organização e manutenção da estrutura militar. / The military recruitment had been a reality in São Paulo, since the 18th century. The conflicts at the Silver Drainage Basin, in search to delimit the Portuguese and Spanish America borders, they had demanded to orgazine the military structure in Brazil. Hosting this structure São Paulo Captainship was chosen. The union of interests, segments of São Paulo s elite and the Portuguese Crown, made it possible the militarization of Captainship consolidation throughout the second half of 18th century. However, the joining of the economy and the paulista society, from the last decades from the 18th and beginning of 19th century, it got in conflict with the militarization developed there. The current paper searched to analyze the differences between the recruitment fulfilled in São Paulo at these two moments, focusing the relations between the society and the State over the organization and maintenance of the military structure.
28

Análise temporal do uso e ocupação do solo da microbacia hidrográfica do córrego do Itaperu/Itapocu, no município de Piracicaba / Temporal analysis of soil use and occupation of Itaperu/Itapocu stream watershed in the municipality of Piracicaba

Bruna Batagin 10 July 2017 (has links)
O presente trabalho foi desenvolvido com o objetivo de analisar, por meio da técnica de fotointerpretação, o uso e ocupação do solo na microbacia hidrográfica do córrego do Itaperu/Itapocu, no município de Piracicaba (SP), do período de 1940 até 2016. Foram utilizadas fotografias aéreas dos anos de 1940, 1978, 2000 e 2005 e imagens dos satélites Rapid Eye e Cbers 4 dos anos de 2011 e 2016. Para tanto, o estudo foi dividido em três etapas que consistiram em primeiro analisar o uso e ocupação do solo na microbacia hidrográfica em todo sua extensão; na sequência foi analisada a evolução de áreas urbanas na microbacia e por último foram verificadas as Áreas de Preservação Permanente. Como resultado da primeira etapa foi identificada uma grande mudança da ocupação dos usos do solo ao longo das décadas estudadas. Na segunda etapa, foi constatado o avanço urbano para a área da microbacia hidrográfica que era totalmente rural e ao longo dos anos passou a ser incorporada no perímetro urbano. Na última etapa ao analisar as Áreas de Preservação Permanente, com o crescimento urbano ocorrido no local, houve a extinção de cinco nascentes e alguns cursos d\'água tiveram seu comprimento reduzido. / The present work was developed with the purpose to analyze, by the photointerpretation technique, the use and occupation of the soil in the watershed of the Itaperu/Itapocu stream in the municipality of Piracicaba (SP), between 1940 and 2016. Aerial photographs from the years 1940, 1978, 2000 and 2005 were used, as well as satellite images of Rapid Eye and Cbers 4 from 2011 and 2016. The study was divided into three steps. First, the use and occupation of the soil in the watershed drainage basin in all its extension were analyzed. Next, the evolution of urban areas in the watershed were investigated. Finally, the Permanent Preservation Areas were studied. In the first stage, it was identified a major shift of the occupation of soil uses over the decades studied. In the second, it was found the urban advance into the hydrographic watershed area, which used to be entirely rural and, over the years, became incorporated into the urban area. In the last step, there was the extinction of five springs and some watercourses had their lengths reduced due to urban growth in the area.
29

Managing Water Resources in the Tigris and Euphrates Drainage Basin: An Inquiry into the Policy Process

Al-Himyari, Abbas Hussien 08 1900 (has links)
The Tigris and Euphrates are international rivers vital to the four countries through which they flow: Turkey, Syria, Iraq, and Iran. The population in the region has more than doubled in less than thirty years, and irrigated agriculture, hydroelectric power generation, industrialization, and urbanization have increased. All of these developments require more water, and the dependence of the riparian nations on the waters of the Tigris and Euphrates Rivers has become apparent, as has the need for comprehensive, basin-wide management of water resources. At present the riparians have shown some concern about the management of water in the two rivers, although no consensus exists as to the precise nature of the problem or what should be done to resolve it. This policy-oriented dissertation attempts to help frame the policy issues of managing the waters of the Tigris and Euphrates basin. It also seeks to provide an understanding of the policy process and to meet the intelligence needs of policy-makers with regard to the future management of these international waterways. Finally, it provides strategies for developing and implementing a cooperative water policy for this international basin.
30

Lithologic Controls on Karst Groundwater Flow, Lost River Groundwater Basin, Warren County, Kentucky

Groves, Christopher 01 January 1987 (has links)
The Lost River Groundwater Drainage Basin in Warren County, Kentucky, is a karst drainage system encompassing 55 square miles (143 square kilometers) developed within the Mississippian St. Louis and Ste. Genevieve Limestones. Near the contact between these two formations are two bedded chert units, the Lost River Chert Bed (Elrod, 1899) within the Ste. Genevieve and the Corydon Chert Member (Woodson, 1983) of the St. Louis, which appear to be perching layers to shallow karst groundwater flow. Groundwater may be seen flowing on top of these beds in various cave streams and at swallets and springs throughout the basin. In order to compare the vertical positions of these layers to shallow karst groundwater flow, geologic structure maps of the Lost River Chert Bed and the Corydon Chert Member were prepared for the basin, along with a contour map of the water table (at or near which shallow karst groundwater flow is assumed to take place) over the same area. These surfaces were digitized, then contoured and compared using SURFACE II and DISSPLA computer graphics systems. Correlation was accepted for points where the water table is either 20 feet (6.1 meters above or below the top of the two chert layers. The water table (at baseflow conditions) was found to correlate with the Lost River Chert Bed over 42.6% of the basin, as well as 40.7% for the Corydon Member. Shallow karst groundwater flow is found to correlated with bedded chert layers over 83.3% of the study area, and therefore it is concluded that chert layers have a dominant effect on the vertical position of groundwater flow within the Lost River Groundwater Drainage Basin.

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