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Late cenozoic landforms, stratigraphy and history of sea level oscillations of southeastern Virginia and northeastern North CarolinaPeebles, Pamela Crowson 01 January 1984 (has links)
A depositional model accounting for the stratigraphic sequences which accumulate during a marine transgression across a dissected coastal plain aids in understanding the geologic history of southeastern Virginia and northeastern North Carolina. Application of this model to the Shirley Formation (middle Pleistocene) and the Sedgefield and Lynnhaven members of the Tabb Formation (late Pleistocene) allows delineation of (1) the facies within, (2) the areal extent of, and (3) the landforms associated with these lithostratigraphic units. Facies within each lithostratigraphic unit consist of (1) a vertical succession from local, basal, channel-fill deposits and coarse, basal, lag deposits which grade upward into finer-grained deposits of estuaries or protected embayments or into medium to coarse sands of former barriers and (2) a lateral succession seaward from estuarine deposits to sediments of protected embayments and barriers. Sediment textures, sedimentary bedding-structures, fossils and plant detritus aid in interpreting paleoenvironments within each lithostratigraphic unit. Each lithostratigraphic unit corresponds to a separate marine transgression. Valleys formed during low stands of sea level subsequently widened and filled during the succeeding marine transgression. Coarse sediments accumulated along the shoreline as the sea advanced landward, forming a discontinuous sheet of basal lag deposits. Finer-grained deposits accumulated in estuaries or protected embayments and intertongue with or are covered by landward-migrating barrier deposits along the seaward margin of each lithostratigraphic unit. Three middle and late Pleistocene sea level oscillations are thus recorded in deposits of southeastern Virginia and northeastern North Carolina.
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A Mathematical Model of Chincoteague Bay, VirginiaVaccaro, John Joseph 01 January 1976 (has links)
No description available.
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Ambientes de confluência no contexto da rede de drenagem : exemplo da bacia hidrográfica do rio Ivaí - estado do Paraná /Santos, Vanessa Cristina dos. January 2015 (has links)
Orientador: José Cândido Stevaux / Banca: Laurent Polidori / Banca: Maurício Meurer / Banca: Maurício Guerreiro Martinho dos Santos / Banca: Isabel Terezinha Leli / Resumo: As confluências de canais constituem ambientes com alterações contínuas na estrutura de fluxo e no transporte de sedimentos. São locais na rede de drenagem em que operam complexas interações entre matéria e energia, proporcionadas pela combinação de fluxos de padrões diferentes. Esta dinâmica peculiar pode influenciar desde aspectos ecológicos até questões de planejamento espacial e de ocupação do espaço. O objetivo principal desta pesquisa foi analisar os ambientes de confluência considerando os aspectos geomorfológicos e hidrossedimentares, e avaliar a influência de fatores locais e regionais sobre estes aspectos. Esta pesquisa parte do pressuposto que a morfologia das confluências está condicionada aos aspectos da rede de drenagem como os geomorfométricos (área, índice de circularidade, densidade de drenagem, ângulo de confluência e entre outros), hidrossedimentólogicos (regime de descarga líquida e sólida, e carga transportada) e geológicos. Para alcançar tal objetivo, primeiramente avaliou-se a qualidade dos dados geomorfométricos extraídos de diferentes Modelos Digitais de Elevação considerando os distintos métodos de aquisição (sensores) e a escala (resolução), para em seguida avaliar aspectos geomorfométricos da rede drenagem. Realizou-se também a regionalização e estimativa de vazões médias e da produção de sedimentos suspensos, tanto para o canal principal da bacia hidrográfica estudada, quanto para os seus afluentes. Também foram avaliadas algumas confluências em campo, a fim de obter dados relativos à estrutura do fluxo, a morfologia e a composição granulométrica, essenciais para a compreensão da dinâmica local das confluências. E por fim, todos os resultados obtidos foram analisados por meio de técnicas de mineração de dados para a avaliação da influência dos aspectos regionais e locais na configuração das confluências. Para este estudo, tomou-se como exemplo a bacia... / Abstract: River channel confluences are sites with continuous changes in the flow structure and the sediment transport. Confluences are also places in the river network operating complex interactions between material and energy, provided by the combination of different patterns flows. This particular dynamic can influence since ecological aspects to spatial planning considerations and occupation of space. The main objective of this research is to analyse the confluence environments considering the geomorphological and hydro-sedimentary aspects and evaluate the influence of local and regional factors on these aspects. This research assumes that the morphology of confluences is conditioned by aspects of river network as geomorphometric (basin size, circularity, drainage density, confluence angle and others), hydrosedimentological (liquid and solid discharge regime and load transported) and geological. To achieve this objective, first it evaluated the quality of geomorphometric data extracted from different Digital Elevation Models considering the different acquisition methods (sensors) and the scale (resolution), to then evaluate geomorphometric aspects of river networks. It also conducted regionalization and estimation average flow and production of suspended load, both the main channel of the studied watershed, and for its tributaries. Also it was evaluated some confluences in the field work to obtain data concerning about flow structure, morphology and granulometric composition essential for understanding the local dynamics of the confluences. Finally, all the results were analysed using data mining techniques for assessing the influence of regional and local aspects in the configuration of confluences. For this study, it took as example the Ivaí watershed, as this has a dam free condition on your main channel and the heterogeneity of its physiographics properties that influence the variability in geomorphological and hydro-sedimentary aspects... / Resume: Les points des confluents des rivières constituent-ils comme d'environnements lesquels les changements dans la structure de flux et dans le transport des sédiments sont considérés continus. Sont des locaux où les réseaux de drainage sont complexes, surtout, dans la relation entre la matière et l'énergie. Une échange proportionné par la combinaison des flux et de standards différents. Cette dynamique particulière peut être influencée par des aspects écologiques, jusqu'à la planification spatiale et l'occupation de l'espace. L'objectif principal de cette recherche a été d'analyser l'environnement des points du confluent en considéraient les aspects géomorphologiques et hydrosédimentaires, et d'évaluer l'influence de ces aspects sur les échelles locales et régionales. Cette recherche considère que la morphologie des points du confluent est conditionnée aux aspects du réseau du drainage comme les géogrammétriques (surface, circularité, densité du drainage, angule de la confluent), hydrosédimentologiques (régime de la décharge liquide et solide, et charge transporté) et géologiques. Pour répondre à tel objectif, nous avons premièrement évalué la qualité des données géomorphométrique extraite à partir des modèles variés : Modèle Numérique de Terrain (MNT) qui considère des méthodes distinctes pour l'acquisition des donnes (capteur) commme l'échelle utilisée (résolution), ensuite nous avons évalué les aspects géomorphométriques du réseau de drainage. Nous avons effectué la régionalisation et estimé les débits moyens et de la production des sédiments suspendus, tant pour le drain principal du bassin versant présenté dans l'étude, autant que pour ses affluents. Également ont été évalués les confluents sur le terrain, pour obtenir les données relatives à la structure de flux, la morphologie, et la composition granulométrique, importants pour la... / Doutor
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Protéger la nature à l'ère de l'anthropocène : Géo-graphies de l'archipel des Galapagos (Equateur) / Nature protection in the Anthopocene era : geo-graphies of the Galapagos (Ecuador)Guyot-Tephany, Josselin 10 September 2019 (has links)
La présente thèse a pour ambition d’interroger les fondements de la protection de la nature à l’ère de l’anthropocène. Le postulat de départ est que l’incapacité à répondre aux enjeux écologiques reflète les contradictions de l’ontologie naturaliste, laquelle s’est imposée comme la conception hégémonique des rapports entre humains et non humains (Descola 2005). L’argumentaire repose sur une analyse critique des politiquesdéveloppées dans un territoire emblématique du naturalisme : l’archipel des Galapagos (Équateur). Lieu fondateur des sciences naturelles, il représente l’archétype le plus abouti des figures, elles-mêmes archétypales, de l’île-laboratoire et de l’île-conservatoire. Il abrite depuis 1959 un parc national couvrant 97% des terres émergées et depuis 1998 une réserve marine parmi les plus vastes au monde. Archipel tropical le mieux conservé du monde, c’est aussi celui qui connaît la dégradation écologique la plus rapide (Snell et al. 2002). Les territoires protégés ont servi de support au développement d’un tourisme de naturequi a enclenché une intégration croissante des îles à l’économie-monde et au reste de l’espace équatorien, rompant ainsi brutalement l’isolement géographique qui garantissait leur intégrité écologique (Grenier 2000). Le tourisme a surtout été le moteur d’une croissance économique et démographique ayant engendré une rapide anthropisation des enclaves peuplées et une profonde transformation de l’espace archipélagique. Bref, les Galapagos représentent un condensé, dans le temps et l’espace, des logiques ayant conduit à entrer dans anthropocène.La thèse propose d’aborder, à travers l’exemple des Galapagos, les enjeux environnementaux de notre époque par une approche renouvelée de la géographie. Fondée comme la science des relations entre les sociétés et leur environnement, cette discipline a été une victime tardive du grand partage entre Nature et Culture se matérialisant actuellement, à propos des questions environnementales, par un tiraillement entre une géographie naturaliste et une géographie du naturalisme. Le présent travail esquisse une voie alternative à ce dualisme en posant les bases d’une géo-graphie de l’anthropocène, c’est-à-dire une étude conjointe des empreintes humaines sur terre et des récits que les acteurs et les sociétés construisent autour de celles-ci. La première partie traite successivement du rôle des territoires insulaires dans l’émergence et l’évolution des politiques de conservation, de la progressive naturalisation des Galapagos et du cadre théorique et méthodologique qui a guidé l’analyse. La deuxième partie montre comment l’ouverture géographique impulsée par l’essor du tourisme de nature a propulsé l’archipel dans l’anthropocène, mettant ainsi à l’épreuve le modèle conservationniste. La dernière partie s’intéresse à la manière dont la nature et le fait insulaire participent à l’affirmation d’un sentiment identitaire (Ospina Peralta 2001) et à des logiques multiformes et multiscalaires l’insularisation entraînant une archipellisation des Galapagos. / The emergence of the conservation movement in the late XIXth century in North America turned natural protected areas into a privileged tool for preserving the living. Designed in the first place as islands of nature shielded from human hold,they were progressively integrated in the 1970s to global environmental policies aiming at reconciling conservation and development. Such a dynamics both led to the increase and diversification of protected areas. However, until now, the development of those structures did not prevent from stopping the reduction of biodiversity, a paradoxical situation that isapplying to all the ecological issues. In spite of a strong global environmental consciousness and an increase of actions, measures and environment-oriented policies, we would have entered into a new epoch characterized by the general and irreversible mark of human activities on the earth : the Anthropocene (Crutzen et Stoermer 2000).This thesis aims at questioning the foundations of nature protection in the Anthropocene era. The starting postulate is that the incapacity to meet environmental issues reflects the contradictions of the naturalist ontology which stood out as thehegemonic conception of the relationships between humans and non-humans (Descola 2005). The argumentation is based on a critical analysis of the policies developed in a territory which is quite emblematic of naturalism, i.e. the Galapagos Archipelago in Ecuador. Being a founding place of natural sciences, it represents the most accomplished archetype of the figures (themselves very archetypical) of the laboratory-island or theconservatory-island. Since 1959, the Galapagos have been sheltering national park covering 97% of the land areas and since 1998 a marine reserve, which is among the largest in the world. As the best-preserved tropical archipelago on earth, it also is the place where the environment deteriorates most rapidly (Snell et al. 2002). The protected areas were used to develop a nature-based tourism leading to an increasing integration of the islands to the world-economy and the rest of the Ecuadorian territory, thus breaking up brutally the geographical isolation that was securing their ecological integrity (ibid.). Above all, tourism was the driving force of the demographic and economic growth, which led to a quick anthropization of populated enclaves and a deep change of the archipelago’s space. In other words, the Galapagos can be seen as a concentrate, in time and space, of the logics leading to the Anthropocene.Through the example of the Galapagos, the thesis deals with the environmental issues of our epoch in order to propose a renewed approach of geography. This discipline, originally founded as the science of the relationships between societies and their environment, was later victim of the great share between Nature and Culture, whichpresently expresses itself by conflicts between a naturalist geography and a geography about naturalism. The present research suggest an alternative way to such a dualism and sets down the bases of a geography of the Anthropocene, i.e. a joint study of the human marks on the earth and the narratives that stakeholders and societies produce about them. The first part successively tackles the role played by insular territories in building conservation policies, the progressive naturalization of the Galapagos and the theoretical and methodological framework conducting our analysis. The second part deals with the way the geographical opening threw the archipelago into the Anthropocene, thus challenging conservation policies. The third part shows how nature and the insular issues pertain to multiform and multiscalar logics, leading to the archipelization of the Galapagos.
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Analysis of the Port of Portland facility hinterlandsWilson, Timothy D. 01 January 1975 (has links)
Most of the United States port authorities delineate their hinterland by the use of freight rate schedules used by inland carriers. The hinterland is defined as that region having favorable rates to and from a port. The use of freight rate schedules can be applied to a) individual commodities or to b) all the commodities moving through a port. The freight rate method is built on the “rational man” concept. That is, a situation is assumed where there is “perfect knowledge” and a desire to minimize transportation costs. This assumption does not always coincide with reality.
This paper classifies commodities according to the facilities required to handle them. This is most relevant to port authorities who decide what special facilities may be needed. This classification is also highly relevant to the delineation of port hinterlands. If a port does not provide a given facility for loading and unloading, commodities requiring that type of facility for handling cannot move through that port.
The delineation of “facility hinterlands” has two advantages. First, it more closely approximates reality than does the use of freight rates. Second, while it is more time consuming than using freight rates, it does not require expenditures of time and money as large as with the determination of individual commodity hinterlands. Facility hinterland delineation, thus, offers an alternative for port authorities.
The Port of Portland has four main groups of facilities for handling imports and exports: dry bulk, break-bulk, containerized cargo and liquid bulk. In addition, the Port of Portland has special import facilities for steel and automobiles, and special export facilities for grain and logs. The major source of data used to obtain the domestic origins and destinations, by tonnage, for each facility group was the 1973 Export and Import Domestic City Origin and Destination Report Quarterly Reports.
The origins and destinations are, in most cases, warehousing and distribution points. Therefore, the hinterlands, as identified, are not necessarily ultimate origin and destination hinterlands, but rather they are hinterlands of transshipment points. A port city is a focal point, a gateway, for inbound and outbound cargo. It is expected, therefore, that Portland should have a larger warehousing sector in its economy, than cities which are not ports, which handles a great deal of cargo that does not originate in, nor is destined for, Portland.
In an attempt to ascertain the volume, by facility group, of cargo that actually originated in or was destined for Portland, a questionnaire was sent to the exporters and importers who handled cargo originating in or destined for Portland. The questionnaire was sent to all exporters and/or importers who handled 100 tons or more in any given quarter of 1973. The data from the responses to the questionnaires was combined with the original data to delineate the Port of Portland's hinterlands.
Edward Ullman's three-factor typology fits the flow of export goods from domestic origins, through the Port of Portland, to foreign destinations. Complementarity, transferability, and intervening opportunity, each represent factors making the northwest quadrant of the United States the Port of Portland's export hinterland. Oregon, Washington, Idaho, Montana, and Wyoming make up the heart of this hinterland to varying degrees generally correlated to distance. The states bordering the hinterland tend to be less important than those in the hinterland, but more important than states even more distant. The three-factor typology, also, fits the flow of import goods from the Port of Portland to domestic destinations. The three factors combine to place the Port of Portland's import hinterland primarily in Oregon and Washington. However, complementarity provides a basis for an extended commodity flow in terms of distance and magnitudes for imports.
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Shared landscape, divergent visions? transboundary environmental management in the Northern Great PlainsBruyneel, Shannon Marie 16 August 2010
The 49th parallel border dividing the Great Plains region has been described since its delimitation as an artificial construct, as no natural features distinguish the Canadian and American portions of the landscape. While the border subjects the landscape to different political, legal, philosophical, and sociocultural regimes on either side, the regions contemporary and emerging environmental problems span jurisdictional boundaries. Their mitigation requires new forms of environmental management capable of transcending these borders. In this dissertation, I examine the prospects for implementing ecosystem-based approaches to environmental management in the Frenchman River-Bitter Creek (FRBC) subregion of the Saskatchewan-Montana borderland. First, I interrogate the extent to which residents perceive the FRBC region as a borderland. Then, I examine the range of implications of ecosystem-based management approaches for institutional arrangements, environmental governance, and traditional property regimes and livelihoods in the region.<p>
The research methodology includes an extensive literature review; multiple site visits to the FRBC region; a series of semi-structured interviews with employees of government agencies and environmental nongovernmental organizations, and with local agricultural producers; the analysis of historical maps and of selected ecoregional planning documents; and attendance at public meetings in the FRBC region. The research results are presented in a series of four manuscripts. The first manuscript describes perceptions of the border and the borderland through time. The second manuscript examines changes to the border and the relationships across it instigated by the September 11, 2001 terrorist attacks and the 2003 BSE Crisis. The third manuscript examines the extent to which a shared landscape transcends the border, and describes how the different regimes across the border create divergent visions for landscape and species management. The fourth manuscript investigates the ways in which incorporating a broader range of actors and disciplines could reconceptualize environmental management as an inclusive processes that is cognizant of local history and values.<p>
By examining the imbrications of the fields of environmental management, border studies, and political ecology, this research advocates adopting an historical approach to environmental geography research so that contemporary problems may be understood within their local contexts. It emphasizes the importance of including a range of stakeholders in environmental management processes. It identifies the difficulties inherent to adopting ecosystem-based approaches to management, and stresses the practical value of transboundary collaboration for goal setting so that the tenets of ecosystem-based management may be achieved under the existing jurisdictional frameworks in place. It provides significant insights for policy makers, in that it presents residents reflections upon their involvement in environmental management processes, and upon the impacts that recent changes to border and national security policies have had upon borderland residents. Moving forward, this research uncovers the need for continued investigations of the impacts of border security policies and legislation on borderland communities and species, for more study of the ability of state agencies to meaningfully incorporate local actors in environmental management, and for investigations of trinational environmental management efforts in the North American Grasslands.
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Shared landscape, divergent visions? transboundary environmental management in the Northern Great PlainsBruyneel, Shannon Marie 16 August 2010 (has links)
The 49th parallel border dividing the Great Plains region has been described since its delimitation as an artificial construct, as no natural features distinguish the Canadian and American portions of the landscape. While the border subjects the landscape to different political, legal, philosophical, and sociocultural regimes on either side, the regions contemporary and emerging environmental problems span jurisdictional boundaries. Their mitigation requires new forms of environmental management capable of transcending these borders. In this dissertation, I examine the prospects for implementing ecosystem-based approaches to environmental management in the Frenchman River-Bitter Creek (FRBC) subregion of the Saskatchewan-Montana borderland. First, I interrogate the extent to which residents perceive the FRBC region as a borderland. Then, I examine the range of implications of ecosystem-based management approaches for institutional arrangements, environmental governance, and traditional property regimes and livelihoods in the region.<p>
The research methodology includes an extensive literature review; multiple site visits to the FRBC region; a series of semi-structured interviews with employees of government agencies and environmental nongovernmental organizations, and with local agricultural producers; the analysis of historical maps and of selected ecoregional planning documents; and attendance at public meetings in the FRBC region. The research results are presented in a series of four manuscripts. The first manuscript describes perceptions of the border and the borderland through time. The second manuscript examines changes to the border and the relationships across it instigated by the September 11, 2001 terrorist attacks and the 2003 BSE Crisis. The third manuscript examines the extent to which a shared landscape transcends the border, and describes how the different regimes across the border create divergent visions for landscape and species management. The fourth manuscript investigates the ways in which incorporating a broader range of actors and disciplines could reconceptualize environmental management as an inclusive processes that is cognizant of local history and values.<p>
By examining the imbrications of the fields of environmental management, border studies, and political ecology, this research advocates adopting an historical approach to environmental geography research so that contemporary problems may be understood within their local contexts. It emphasizes the importance of including a range of stakeholders in environmental management processes. It identifies the difficulties inherent to adopting ecosystem-based approaches to management, and stresses the practical value of transboundary collaboration for goal setting so that the tenets of ecosystem-based management may be achieved under the existing jurisdictional frameworks in place. It provides significant insights for policy makers, in that it presents residents reflections upon their involvement in environmental management processes, and upon the impacts that recent changes to border and national security policies have had upon borderland residents. Moving forward, this research uncovers the need for continued investigations of the impacts of border security policies and legislation on borderland communities and species, for more study of the ability of state agencies to meaningfully incorporate local actors in environmental management, and for investigations of trinational environmental management efforts in the North American Grasslands.
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Environmental Change and Place-Based Identities: Sponge Fishing in Tarpon Springs, FloridaSuver, Michael 01 January 2012 (has links)
Abstract
As the environmental consequences of urbanization and climate change become apparent in coastal communities, it has become important to understand how residents of these communities experience and approach their changing environments. This becomes especially significant in places where nature-based livelihoods constitute a major part of the economy. This thesis focuses on the city of Tarpon Springs, located along the Gulf of Mexico in Florida, where sea sponge fishing is an important contributor to the local economy while also being central to place-based tourist and ethnic identities. It seeks to understand how environmental changes in the sea sponge economy will affect the coastal economy of Tarpon Springs.
Based on interviews conducted with people closely connected with the sponge fishing economy, including sponge fishers and shops selling sponges, the thesis delves into (i) local perspectives on changing environmental conditions, (ii) how such changes will impact the future of sponge fishing and (iii) the extent to which local governmental support has been sought by sponge fishers and shops. Sponge fishing in Tarpon Springs is connected to its Greek identity so changes in the sponge economy could potentially affect whether tourist experiences which highlight Greek identity linked to sponge fishing continue to be connected to an actual Greek economic presence or reflect nostalgia for a Greek past.
The interview responses showed concerns about declining sponge hauls which were connected to more immediate experiences of environmental change and pollution, including red tide events and phosphate runoff. Respondents also reflected on how climate change will exacerbate such environmental issues through rising water temperatures. Respondents viewed Tarpon Springs as a community with a strong Greek identity and sponge shop owners especially seemed to be dependent on links with an active sponge fishing economy to enhance the value of their sponges for tourists. In terms of government support, those involved in the sponge economy had very little interaction with city officials and did not seem keen to enhance such interactions.
This thesis thus reveals that the economy of Tarpon Springs continues to be shaped by sponge fishing livelihoods that are directly dependent on nature. However, it seems that concerns related to environmental change remain within the local community and are not being voiced through more public forums, such as through active engagement with local government. The future of Tarpon Springs and its sponge fishing economy therefore remains uncertain, even as local participants in the sponge economy continue to work towards maintaining their unique identity.
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Examining Land Use/Land Cover Change and Potential Causal Factors in the Context of Climate Change in Sagarmatha National Park, NepalHumagain, Kamal 01 December 2012 (has links)
In the context of growing tourism and global warming, the fragile landscape of the Himalayas is under immense pressure because of rapid land cover changes in developing countries like Nepal. Remotely sensed data combined with ethnographic knowledge are useful tools for studying such changes. The quantitative change can be measured analyzing satellite images whereas local people’s perceptions provide supportive information. To measure such changes in Sagarmatha National Park of Nepal, Multispectral Scanner (MSS) and Thematic Mapper (TM) images since 1972 were used. Normalized Difference Vegetation Index (NDVI) was calculated for different elevation classes and land cover types. These measurements, along with land cover change (1992- 2006) analysis, shows a significant conversion of the areas covered by ice, shrub and grass to rock and soil. Factors including political conflict due to a Maoist rebellion group, inactive park management, increasing tourist demand, and consequent natural resources exploitation helped to explain the change in the forested areas. This is supported by the information from short, informal, semi-structured interviews with local people. However, the local people are unaware of global warming, which has caused the ice melting and glacial lake expansion. Although global causes are out of the immediate control of land managers, better management practices and managed tourism might help alleviate deteriorating Himalayan ecosystems.
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Ambientes de confluência no contexto da rede de drenagem: exemplo da bacia hidrográfica do rio Ivaí - estado do ParanáSantos, Vanessa Cristina dos [UNESP] 29 October 2015 (has links) (PDF)
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000865825.pdf: 33966612 bytes, checksum: 6d6b38cef8dfccb96168a99545797b93 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Les points des confluents des rivières constituent-ils comme d'environnements lesquels les changements dans la structure de flux et dans le transport des sédiments sont considérés continus. Sont des locaux où les réseaux de drainage sont complexes, surtout, dans la relation entre la matière et l'énergie. Une échange proportionné par la combinaison des flux et de standards différents. Cette dynamique particulière peut être influencée par des aspects écologiques, jusqu'à la planification spatiale et l'occupation de l'espace. L'objectif principal de cette recherche a été d'analyser l'environnement des points du confluent en considéraient les aspects géomorphologiques et hydrosédimentaires, et d'évaluer l'influence de ces aspects sur les échelles locales et régionales. Cette recherche considère que la morphologie des points du confluent est conditionnée aux aspects du réseau du drainage comme les géogrammétriques (surface, circularité, densité du drainage, angule de la confluent), hydrosédimentologiques (régime de la décharge liquide et solide, et charge transporté) et géologiques. Pour répondre à tel objectif, nous avons premièrement évalué la qualité des données géomorphométrique extraite à partir des modèles variés : Modèle Numérique de Terrain (MNT) qui considère des méthodes distinctes pour l'acquisition des donnes (capteur) commme l'échelle utilisée (résolution), ensuite nous avons évalué les aspects géomorphométriques du réseau de drainage. Nous avons effectué la régionalisation et estimé les débits moyens et de la production des sédiments suspendus, tant pour le drain principal du bassin versant présenté dans l'étude, autant que pour ses affluents. Également ont été évalués les confluents sur le terrain, pour obtenir les données relatives à la structure de flux, la morphologie, et la composition granulométrique, importants pour la... / As confluências de canais constituem ambientes com alterações contínuas na estrutura de fluxo e no transporte de sedimentos. São locais na rede de drenagem em que operam complexas interações entre matéria e energia, proporcionadas pela combinação de fluxos de padrões diferentes. Esta dinâmica peculiar pode influenciar desde aspectos ecológicos até questões de planejamento espacial e de ocupação do espaço. O objetivo principal desta pesquisa foi analisar os ambientes de confluência considerando os aspectos geomorfológicos e hidrossedimentares, e avaliar a influência de fatores locais e regionais sobre estes aspectos. Esta pesquisa parte do pressuposto que a morfologia das confluências está condicionada aos aspectos da rede de drenagem como os geomorfométricos (área, índice de circularidade, densidade de drenagem, ângulo de confluência e entre outros), hidrossedimentólogicos (regime de descarga líquida e sólida, e carga transportada) e geológicos. Para alcançar tal objetivo, primeiramente avaliou-se a qualidade dos dados geomorfométricos extraídos de diferentes Modelos Digitais de Elevação considerando os distintos métodos de aquisição (sensores) e a escala (resolução), para em seguida avaliar aspectos geomorfométricos da rede drenagem. Realizou-se também a regionalização e estimativa de vazões médias e da produção de sedimentos suspensos, tanto para o canal principal da bacia hidrográfica estudada, quanto para os seus afluentes. Também foram avaliadas algumas confluências em campo, a fim de obter dados relativos à estrutura do fluxo, a morfologia e a composição granulométrica, essenciais para a compreensão da dinâmica local das confluências. E por fim, todos os resultados obtidos foram analisados por meio de técnicas de mineração de dados para a avaliação da influência dos aspectos regionais e locais na configuração das confluências. Para este estudo, tomou-se como exemplo a bacia... / River channel confluences are sites with continuous changes in the flow structure and the sediment transport. Confluences are also places in the river network operating complex interactions between material and energy, provided by the combination of different patterns flows. This particular dynamic can influence since ecological aspects to spatial planning considerations and occupation of space. The main objective of this research is to analyse the confluence environments considering the geomorphological and hydro-sedimentary aspects and evaluate the influence of local and regional factors on these aspects. This research assumes that the morphology of confluences is conditioned by aspects of river network as geomorphometric (basin size, circularity, drainage density, confluence angle and others), hydrosedimentological (liquid and solid discharge regime and load transported) and geological. To achieve this objective, first it evaluated the quality of geomorphometric data extracted from different Digital Elevation Models considering the different acquisition methods (sensors) and the scale (resolution), to then evaluate geomorphometric aspects of river networks. It also conducted regionalization and estimation average flow and production of suspended load, both the main channel of the studied watershed, and for its tributaries. Also it was evaluated some confluences in the field work to obtain data concerning about flow structure, morphology and granulometric composition essential for understanding the local dynamics of the confluences. Finally, all the results were analysed using data mining techniques for assessing the influence of regional and local aspects in the configuration of confluences. For this study, it took as example the Ivaí watershed, as this has a dam free condition on your main channel and the heterogeneity of its physiographics properties that influence the variability in geomorphological and hydro-sedimentary aspects...
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