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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.
331

The challenge of implementing integrated water resources management (IWRM) in the Lower Okavango River Basin, Ngamiland district, Botswana.

Kgomotso, Phemo Karen January 2005 (has links)
Water resources management practice has undergone changes in management approaches and principles over time. It was previously characterised by what scholars refer to as the hydraulic mission where ‘extreme engineering’ was the order of the day (Allan, 2003). As Radif (1999) argues, water resources managers and policy makers were initially driven to manage and supply water to people for its direct use / these included drinking, growing food, and providing power for domestic and industrial use. This modus operandi continued until the end of the 1970s. Over two decades later, this focus is still prevalent in many countries in southern Africa including Botswana. As Swatuk and Rahm (2004) state, “augmenting supply is a continuing focus of government activity”. The National Water Master Plan (NWMP) is the current policy document guiding water resources management in Botswana and it focuses on supply-side interventions in response to increasing water demand. According to SMEC et al. (1991), the consulting company that conducted the NWMP study, “the investigation and studies... indicated the need for the continuing development of water supplies throughout Botswana over the next 30 years”. Based on these observations, government has developed significant human and technical capacity in exploiting both surface and groundwater resources (Swatuk and Rahm, 2004).
332

Arqueologia guarani na bacia do rio Santo Anastácio-SP: estudo do sítio Célia Maria / Guarani Archaeology the River Basin Santo Anastácio - SP: Study Site Célia Maria

Pereira, David Lugli Turtera 29 February 2012 (has links)
A pesquisa realizada na área do Sítio Arqueológico Célia Maria, localizado na região da Bacia do Rio Santo Anastácio (afluente da Bacia do Paraná), Estado de São Paulo, demonstrou uma ocupação guarani pré-colonial. A cerâmica foi datada por termoluminescência, situando a ocupação em torno de 450±60 anos atrás. Este trabalho traz dados referentes à cerâmica identificada na área do Sítio Célia Maria, que também apresentou três manchas pretas, lítico polido e possível estrutura de combustão. A partir da análise tecno-tipológica da cerâmica, demonstramos a sequência dos gestos técnicos para a produção dos artefatos, assim como reconstituímos graficamente a forma de vasos, a partir de fragmentos de bordas. Essas reconstituições possibilitaram inferir a forma e a função dos antigos recipientes guarani. Os dados espaciais somados às características dos atributos cerâmicos do Sítio Célia Maria foram confrontados com outras pesquisas disponíveis que versaram sobre a presença dos guarani na Bacia do Paraná e Paranapanema. / The research conducted in the archaeological site area Célia Maria, located in the River Basin Santo Anastácio (tributary of the Paraná Basin), State of São Paulo, demonstrated a precolonial Guarani occupation. The pottery was dated by thermoluminescence, standing occupation around 450±60 years ago. This work has data concerning pottery indentified in Site Célia Maria, who also had three black spots, polished lytic and as possible combustion structure. From the techno-typological ceramics analysis, we demonstrated the gestures sequence to the production of technical artifacts, as well as graphically reconstitute the form of vessels, from fragments of edges. These reconstructions allowed inferring the shape and function of the ancient Guarani containers. The data added to the spatial characteristics of ceramics tributes of Site Célia Maria were compared with other available research that focused on the presence of the Guarani in the Basin of Paraná and Paranapanema.
333

Revisão sistemática, tafonomia, distribuição geográfica e estratigráfica da classe Tentaculitoidea no Devoniano brasileiro / Systematic review, taphonomy, geographic and stratigraphic distribution of Tentaculitoidea class in Brazilian Devonian.

Comniskey, Jeanninny Carla 01 July 2016 (has links)
Os tentaculitoideos são invertebrados marinhos extintos comumente encontrados nos estratos devonianos brasileiros. São reconhecidos pelo formato da concha coniforme carbonática com pequenas dimensões. Na América do Sul, o registro dos primeiros tentaculitoideos ocorreu durante o início do Siluriano, com o gênero Tentaculites. Representantes das ordens Dacryoconarida e Homoctenida foram encontrados a partir do Devoniano Inferior. No Brasil o grupo possui registro nas bacias do Paraná (Formações Ponta Grossa e São Domingos), Amazonas (Formações Maecuru e Ererê) e Parnaíba (Formação Cabeças). As análises sistemáticas demonstraram a presença dos gêneros Tentaculites e Styliolina (foram constatados nas Bacias do Amazonas, Paraná e Parnaíba) e Uniconus e Homoctenus (registro apenas para a Bacia do Paraná). Foram reconhecidos 8 representantes da ordem Tentaculitida, 2 da ordem Homoctenida e 2 dacryoconarídeos. As espécies Tentaculites crotalinus, Tentaculites jaculus, Tentaculites kozlowskius, Tentaculites paranaensis, Uniconus ciguelius, Homoctenus katzerius e Styliolina cf. Styliolina fissurella foram encontradas na Bacia do Paraná. Já as espécies Tentaculites eldredgianus, Tentaculites trombetensis e Styliolina clavulus encontradas nas Bacias do Amazonas e do Parnaíba. Enquanto que a espécie Tentaculites stubeli somente registrada para a Bacia do Amazonas e Tentaculites oseryi apenas para a Bacia do Parnaíba. Nas bacias do Amazonas e do Parnaíba só existe registro das ordens Tentaculitida e Dacryoconarida. Verificaram-se dois padrões de preservação: espécimes isolados e agrupados, desses padrões foram estabelecidas 6 classes tafonômicas, as quais foram distribuídas de acordo com a paleobatimetria, foram registradas em ambientes de shoreface, offshore transicional e offshore. Foi observado que os tentaculitoideos do Devoniano da Bacia do Paraná possuem uma preferência por ambientes mais calmos, localizados entre o Nível de Base de Tempo Bom (NBOTB) e o Nível de Base de Tempestade (NBOT). As classes analisadas encontram-se distribuídas entre as sequências B e E do Devoniano da Bacia do Paraná. Não foram encontradas feições bioestratinômicas como incrustação e predação. As análises com Espectroscopia de Energia Dispersiva (MEV-EDS) e Energia Dispersiva de Fluorescência de Raios-X (EDXRF) evidenciaram a presença de crômio e pirita nas amostras, características de ambientes anóxicos, corroborando com a hipótese que a extinção da classe esteja relacionada a uma grande extinção global. / The Tentaculitoidea are extinct invertebrates, exclusively marine, commonly found in Brazilian Devonian strata. They are recognized by the conic shell shape, this being, carbonate with small dimensions. In South America, the record of the first tentaculitoideos occurred during the early Silurian, with Tentaculites genus. Representatives of Dacryoconarida and Homoctenida orders were found from the Lower Devonian. In Brazil, the group is registered in the Paraná basins (Ponta Grossa and São Domingo Formations), Amazonas (Maecuru and Ererê Formations) and Parnaíba (Cabeças Formation). Systematic analysis showed the presence of Tentaculites and Styliolina genus (were found in the Amazon, Paraná and Parnaíba Basin) Uniconus and Homoctenus (registration only for the Paraná Basin). Were registered 8 representatives of Tentaculitida order, 2 Homoctenida order and 2 dacryoconarídeos. The species Tentaculites crotalinus, Tentaculites jaculus, Tentaculites kozlowskius, Tentaculites paranaensis, Uniconus ciguelius, Homoctenus katzerius e Styliolina cf. Styliolina fissurella were found in the Paraná Basin. Already species Tentaculites eldredgianus, Tentaculites trombetensis and Styliolina clavulus found in the Amazonas and Parnaíba Basin. While Tentaculites stubeli only recorded for the Amazonas Basin and Tentaculites oseryi only for the Parnaíba Basin. In the Amazonas and Parnaíba basins exists only record of Tentaculitida and Dacryoconarida orders. Two preservation patterns were observed: isolated and grouped specimens. Were established 6 Taphonomic classes, which were distributed according to paleobathymetry were recorded in shoreface environments, offshore transitional and offshore. It was observed that the Tentaculitoidea of the Paraná Basin have a preference for quieter environments, located between the Fair Weather Wave-Base (FWWB) and Storm Wave-Base (SWB). The analyzed classes are distributed among the sequences B and E in the Devonian of the Paraná Basin. There were no biostratinomy features as incrustation and predation. The analysis with energy dispersive spectroscopy (SEM-EDS) and Energy Dispersive Fluorescence X-rays (EDXRF) revealed the presence of chromium and pyrite in the samples, characteristic of anoxic environments, supporting the hypothesis that the extinction of the class is related a major global extinction.
334

Sequence stratigraphy of the Paleocene to Miocene Gambier Sub-basin, southern Australia / Rosalie M. Pollock.

Pollock, Rosalie Miranda January 2003 (has links)
Maps in pocket inside back cover. / Includes published papers and abstracts of works by the author / "November 2003" / Includes bibliographical references. / Various paging : ill. (chiefly col.), maps, plates, charts (some folded) ; 30 cm. + 2 scaled seismic survey maps / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, School of Earth and Environmental Sciences, National Centre for Petroleum Geology and Geophysics and Discipline of Geology and Geophysics, 2004
335

En studie av retentionen i floden Oder och dess avrinningsområden, Polen. / Investigation on the riverine retention in the Odra River, Poland

Dorozynska, Dorota January 2004 (has links)
<p>Nutrient enrichment is the main cause of the increasing eutrophication process in the Baltic Sea during last century. A prerequisite counteract this process the load of nutrients to the Sea must be investigated. The large contribution of nutrients to the Sea is caused by emission from the rivers within the drainage basin. For the total emission of nutrient into the Sea the retention process in the rivers has big influence. This process in the river system has been assumed as a not important part of the nutrient cycle. However some investigators have pointed out that the retention process occurs in the river and be an important part of the nutrient dynamics in the river. For the object of investigation the Odra River Basin was chosen, as an example of a large river basin in the Baltic Sea Drainage Basin. The Odra River is mainly localized in Poland and contributes substantially to the eutrophication of the Baltic Proper. The Odra River is one of the least dammed major rivers of the Baltic Proper and as such of especial interest in retention studies. The phosphorus was chosen as an example of nutrient in the eutrophication process. The purpose of the investigation is to determine the phosphorus retention within the river. Two different models were used to calculate the retention process in the river. The"Multiple Regression Model"turned out to be insignificant, therefore the results were computed by using a “similarity model”, based on similarities between load from monitored tributary basins and the rest of the sub-basin. The retention in the Odra River in the amounted to -4608 t yr-1, which is 43% of the total phosphorus emission to the Odra River. There is also stated that in the Notec and the Warta rivers the retention process occur in the amount of -1940 t yr-1 and -3007 t yr-1 respectively.</p>
336

En studie av retentionen i floden Oder och dess avrinningsområden, Polen. / Investigation on the riverine retention in the Odra River, Poland

Dorozynska, Dorota January 2004 (has links)
Nutrient enrichment is the main cause of the increasing eutrophication process in the Baltic Sea during last century. A prerequisite counteract this process the load of nutrients to the Sea must be investigated. The large contribution of nutrients to the Sea is caused by emission from the rivers within the drainage basin. For the total emission of nutrient into the Sea the retention process in the rivers has big influence. This process in the river system has been assumed as a not important part of the nutrient cycle. However some investigators have pointed out that the retention process occurs in the river and be an important part of the nutrient dynamics in the river. For the object of investigation the Odra River Basin was chosen, as an example of a large river basin in the Baltic Sea Drainage Basin. The Odra River is mainly localized in Poland and contributes substantially to the eutrophication of the Baltic Proper. The Odra River is one of the least dammed major rivers of the Baltic Proper and as such of especial interest in retention studies. The phosphorus was chosen as an example of nutrient in the eutrophication process. The purpose of the investigation is to determine the phosphorus retention within the river. Two different models were used to calculate the retention process in the river. The"Multiple Regression Model"turned out to be insignificant, therefore the results were computed by using a “similarity model”, based on similarities between load from monitored tributary basins and the rest of the sub-basin. The retention in the Odra River in the amounted to -4608 t yr-1, which is 43% of the total phosphorus emission to the Odra River. There is also stated that in the Notec and the Warta rivers the retention process occur in the amount of -1940 t yr-1 and -3007 t yr-1 respectively.
337

Shelf-edge deltas : stratigraphic complexity and relationship to deep-water deposition

Dixon, Joshua Francis 08 November 2013 (has links)
This research investigates the character and significance of shelf-edge deltas within the sedimentary source-to-sink system, and how variability at the shelf edge leads to different styles of deep-water deposition. Because the shelf-edge represents one of the key entry points for terrigenous sediment to be delivered into the deep water, understanding of the sedimentary processes in operation at these locations, and the character of sediment transported through these deltas is critical to understanding of deep-water sedimentary systems. The research was carried out using three datasets: an outcrop dataset of 6000 m of measured sections from the Permian-Triassic Karoo Basin, South Africa, a 3D seismic data volume from the Eocene Northern Santos Basin, offshore Brazil and a dataset of 29 previously published descriptions of shelf-edge deltas from a variety of locations and data types. The data presented highlight the importance of sediment instability in the progradation of basin margins, and deep-water transport of sediment. The strata of the Karoo Basin shelf margin represent river-dominated delta deposits that become more deformed as the shelf-edge position is approached. At the shelf edge, basinward dipping, offlapping packages of soft-sediment-deformed and undeformed strata record repetitive collapse and re-establishment of shelf-edge mouth bar packages. The offlapping strata of the Karoo outcrops record progradation of the shelf margin through accretion of the shelf-edge delta, for over 1 km before subsequent transgression. The Eocene Northern Santos Basin shelf margin, in contrast, exhibits instability features which remove kilometers-wide wedges of the outer shelf that are transported to the basin floor to be deposited as mass-transport packages. In this example, shelf-edge progradation is achieved through „stable. accretion of mixed turbidites and contourites. The data also emphasize the importance of the role of shelf-edge delta processes in the delivery of sediment to the basin floor. A global dataset of 29 examples of shelf-edge systems strongly indicates that river domination of the shelf-edge system (as read from cores, well logs or isopach maps) serves as a more reliable predictor of deep-water sediment delivery and deposition than relative sea level fall as traditionally read in shelf-edge trajectories or sequence boundaries. / text
338

INDIAN CONTINENTAL MARGIN GAS HYDRATE PROSPECTS: RESULTS OF THE INDIAN NATIONAL GAS HYDRATE PROGRAM (NGHP) EXPEDITION 01

Collett, Timothy S., Riedel, Michael, Cochran, J.R., Boswell, Ray, Kumar, Pushpendra, Sathe, A.V. 07 1900 (has links)
Studies of geologic and geophysical data from the offshore of India have revealed two geologically distinct areas with inferred gas hydrate occurrences: the passive continental margins of the Indian Peninsula and along the Andaman convergent margin. The Indian National Gas Hydrate Program (NGHP) Expedition 01 was designed to study the occurrence of gas hydrate off the Indian Peninsula and along the Andaman convergent margin with special emphasis on understanding the geologic and geochemical controls on the occurrence of gas hydrate in these two diverse settings. NGHP Expedition 01 established the presence of gas hydrates in Krishna- Godavari, Mahanadi and Andaman basins. The expedition discovered one of the richest gas hydrate accumulations yet documented (Site 10 in the Krishna-Godavari Basin), documented the thickest and deepest gas hydrate stability zone yet known (Site 17 in Andaman Sea), and established the existence of a fully-developed gas hydrate system in the Mahanadi Basin (Site 19).
339

Mercury biomagnification in the upper South Saskatchewan River Basin

Brinkmann, Lars, University of Lethbridge. Faculty of Arts and Science January 2007 (has links)
In this thesis mercury concentrations in biota of the upper South Saskatchewan River Basin are assessed in three non-industrialized systems. Mercury levels in large sport fish (northern pike, walleye, lake trout) frequently exceeded the consumption limit of 0.5ppm. Goldeye and mooneye of the Oldman River and lake whitefish of Waterton Lakes were below 0.5ppm total mercury. Agricultural and urban effluents constituted no sources of significant mercury loadings to the Oldman River. A doubling of mercury biomagnification factors between longnose dace and their food suggests bioenergetic heterogeneity of these fish along the river gradient. Basin-specific mercury levels were detected for the upper and middle basins in Waterton Lakes, and are associated with food web characteristics, and fish bioenergetics. High mercury levels in a new reservoir were in part attributed to increased loadings from flooded soils, as is commonly observed, but also to bioenergetic constraints and growth inefficiency as a result of non-piscivory of this population. / xiii, 130 leaves : ill. ; 29 cm. --
340

The challenge of implementing integrated water resources management (IWRM) in the Lower Okavango River Basin, Ngamiland district, Botswana.

Kgomotso, Phemo Karen January 2005 (has links)
Water resources management practice has undergone changes in management approaches and principles over time. It was previously characterised by what scholars refer to as the hydraulic mission where ‘extreme engineering’ was the order of the day (Allan, 2003). As Radif (1999) argues, water resources managers and policy makers were initially driven to manage and supply water to people for its direct use / these included drinking, growing food, and providing power for domestic and industrial use. This modus operandi continued until the end of the 1970s. Over two decades later, this focus is still prevalent in many countries in southern Africa including Botswana. As Swatuk and Rahm (2004) state, “augmenting supply is a continuing focus of government activity”. The National Water Master Plan (NWMP) is the current policy document guiding water resources management in Botswana and it focuses on supply-side interventions in response to increasing water demand. According to SMEC et al. (1991), the consulting company that conducted the NWMP study, “the investigation and studies... indicated the need for the continuing development of water supplies throughout Botswana over the next 30 years”. Based on these observations, government has developed significant human and technical capacity in exploiting both surface and groundwater resources (Swatuk and Rahm, 2004).

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