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A GIS expert system for the delineation of watersheds in low-relief regions with rural infrastructureDuke, Guy D., University of Lethbridge. Faculty of Arts and Science January 2003 (has links)
Grid-based digital elevation models (DEMs) are used to simulate overland flow paths in hydrological models. The accuracy of these drainage patterns are dependent upon how well the DEM represents the terrain features that control runoff patterns. Often regional DEMs are not produced at scales small enough to represent rural infrastructure. The scale of runoff patterns that can be accurately modeled is, therefore, restricted, particularly when the terrain is relatively flat. The RIDEM (Rural Infrastructure Digital Elevation Model) model is presented that utilizes commonly available ancillary data to downscale grid-based runoff patterns. The resulting drainage patterns reflect drainage modifications imposed by rural infrastructure including: roads, ditches, culverts, and irrigation canals. Downscaling runoff patterns enables the completion of runoff studies at smaller scales. The model was implemented with the Oldman River watershed, Alberta, Canada to determine the spatial patterns of potential runoff contributing areas in three agricultural watersheds regularly contaminated by pathogens. / vii, 170 leaves : ill. (some col.) ; 29 cm.
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Implications of GRACE Satellite Gravity Measurements for Diverse Hydrological ApplicationsYirdaw-Zeleke, Sitotaw 09 April 2010 (has links)
Soil moisture plays a major role in the hydrologic water balance and is the basis for most hydrological models. It influences the partitioning of energy and moisture inputs at the land surface. Because of its importance, it has been used as a key variable for many hydrological studies such as flood forecasting, drought studies and the determination of groundwater recharge. Therefore, spatially distributed soil moisture with reasonable temporal resolution is considered a valuable source of information for hydrological model parameterization and validation. Unfortunately, soil moisture is difficult to measure and remains essentially unmeasured over spatial and temporal scales needed for a number of hydrological model applications.
In 2002, the Gravity Recovery And Climate Experiment (GRACE) satellite platform was launched to measure, among other things, the gravitational field of the earth. Over its life span, these orbiting satellites have produced time series of mass changes of the earth-atmosphere system. The subsequent outcome of this, after integration over a number of years, is a time series of highly refined images of the earth's mass distribution. In addition to quantifying the static distribution of mass, the month-to-month variation in the earth's gravitational field are indicative of the integrated value of the subsurface total water storage for specific catchments. Utilization of these natural changes in the earth's gravitational field entails the transformation of the derived GRACE geopotential spherical harmonic coefficients into spatially varying time series estimates of total water storage. These remotely sensed basin total water storage estimates can be routinely validated against independent estimates of total water storage from an atmospheric-based water balance approach or from well calibrated macroscale hydrologic models. The hydrological relevance and implications of remotely estimated GRACE total water storage over poorly gauged, wetland-dominated watershed as well as over a deltaic region underlain by a thick sand aquifer in Western Canada are the focus of this thesis.
The domain of the first case study was the Mackenzie River Basin wherein the
GRACE total water storage estimates were successfully inter-compared and validated with the atmospheric based water balance. These were then used to assess the WATCLASS hydrological model estimates of total water storage. The outcome of this inter-comparison revealed the potential application of the GRACE-based approach for the closure of the hydrological water balance of the Mackenzie River Basin as well as a dependable source of data for the calibration of traditional hydrological models.
The Mackenzie River Basin result led to a second case study where the GRACE-based total water storage was validated using storage estimated from the atmospheric-based water balance P-E computations in conjunction with the measured streamflow records for the Saskatchewan River Basin at its Grand Rapids outlet in Manitoba. The fallout from this comparison was then applied to the characterization of the Prairie-wide 2002/2003 drought enabling the development of a new drought index now known as the Total Storage Deficit Index (TSDI). This study demonstrated the potential application of the GRACE-based technique as a tool for drought characterization in the Canadian Prairies.
Finally, the hydroinformatic approach based on the artificial neural network (ANN) enabled the downscaling of the groundwater component from the total water storage estimate from the remote sensing satellite, GRACE. This was subsequently explored as an alternate source of calibration and validation for a hydrological modeling application over the Assiniboine Delta Aquifer in Manitoba. Interestingly, a high correlation exists between the simulated groundwater storage from the coupled hydrological model, CLM-PF and the downscaled groundwater time series storage from the remote sensing satellite GRACE over this 4,000 km2 deltaic basin in Canada.
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Implications of GRACE Satellite Gravity Measurements for Diverse Hydrological ApplicationsYirdaw-Zeleke, Sitotaw 09 April 2010 (has links)
Soil moisture plays a major role in the hydrologic water balance and is the basis for most hydrological models. It influences the partitioning of energy and moisture inputs at the land surface. Because of its importance, it has been used as a key variable for many hydrological studies such as flood forecasting, drought studies and the determination of groundwater recharge. Therefore, spatially distributed soil moisture with reasonable temporal resolution is considered a valuable source of information for hydrological model parameterization and validation. Unfortunately, soil moisture is difficult to measure and remains essentially unmeasured over spatial and temporal scales needed for a number of hydrological model applications.
In 2002, the Gravity Recovery And Climate Experiment (GRACE) satellite platform was launched to measure, among other things, the gravitational field of the earth. Over its life span, these orbiting satellites have produced time series of mass changes of the earth-atmosphere system. The subsequent outcome of this, after integration over a number of years, is a time series of highly refined images of the earth's mass distribution. In addition to quantifying the static distribution of mass, the month-to-month variation in the earth's gravitational field are indicative of the integrated value of the subsurface total water storage for specific catchments. Utilization of these natural changes in the earth's gravitational field entails the transformation of the derived GRACE geopotential spherical harmonic coefficients into spatially varying time series estimates of total water storage. These remotely sensed basin total water storage estimates can be routinely validated against independent estimates of total water storage from an atmospheric-based water balance approach or from well calibrated macroscale hydrologic models. The hydrological relevance and implications of remotely estimated GRACE total water storage over poorly gauged, wetland-dominated watershed as well as over a deltaic region underlain by a thick sand aquifer in Western Canada are the focus of this thesis.
The domain of the first case study was the Mackenzie River Basin wherein the
GRACE total water storage estimates were successfully inter-compared and validated with the atmospheric based water balance. These were then used to assess the WATCLASS hydrological model estimates of total water storage. The outcome of this inter-comparison revealed the potential application of the GRACE-based approach for the closure of the hydrological water balance of the Mackenzie River Basin as well as a dependable source of data for the calibration of traditional hydrological models.
The Mackenzie River Basin result led to a second case study where the GRACE-based total water storage was validated using storage estimated from the atmospheric-based water balance P-E computations in conjunction with the measured streamflow records for the Saskatchewan River Basin at its Grand Rapids outlet in Manitoba. The fallout from this comparison was then applied to the characterization of the Prairie-wide 2002/2003 drought enabling the development of a new drought index now known as the Total Storage Deficit Index (TSDI). This study demonstrated the potential application of the GRACE-based technique as a tool for drought characterization in the Canadian Prairies.
Finally, the hydroinformatic approach based on the artificial neural network (ANN) enabled the downscaling of the groundwater component from the total water storage estimate from the remote sensing satellite, GRACE. This was subsequently explored as an alternate source of calibration and validation for a hydrological modeling application over the Assiniboine Delta Aquifer in Manitoba. Interestingly, a high correlation exists between the simulated groundwater storage from the coupled hydrological model, CLM-PF and the downscaled groundwater time series storage from the remote sensing satellite GRACE over this 4,000 km2 deltaic basin in Canada.
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Investigation Of The Safe And Sustainable Yields For The Sandy Complex Aquifer System In Ergene River BasinOkten, Sebnem 01 July 2004 (has links) (PDF)
This study aims to determine the safe and sustainable development and management of groundwater resources in Ergene River Basin located in northwestern Turkey. A numerical groundwater model was developed for the Sandy Complex aquifer, which is the most productive and the most widespread aquifer in the basin. The finite difference model with 5900 cells was used to represent the steady and unsteady flow in the aquifer. The model was calibrated in two steps: a steady state calibration by using the observed groundwater levels of January 1970, followed by a transient calibration by using the observed groundwater levels for the period of January 1970 and December 2000.
The resulting model was used to develop groundwater pumping scenarios in order to predict the changes in the aquifer system under a set of different pumpage conditions for a planning period of 30 years between January 2001 and December 2030. A total of eight pumping scenarios were developed under transient flow conditions for the planning period and the results were evaluated to determine the safe and sustainable yields of the aquifer. The results, presented in the form of a trade-off curve, demonstrate that the continuation of the present pumping rates exceeds both the safe and the sustainable yields of the aquifer system.
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Mapping riparian vegetation functions using remote sensing and terrain analysis /Lymburner, Leo. January 2005 (has links)
Thesis (Ph.D.)--University of Melbourne, Dept. of Civil and Environmental Engineering, 2006. / Typescript. Includes bibliographical references (leaves [1]-[10])
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Evidence for fluival-controlled coal deposition in the upper Tongue River Member (Fort Union Formation, Paleocene), Powder River Basin, WyomingBauders, Coen M. January 2000 (has links)
Thesis (M.S.)--West Virginia University, 2000. / Title from document title page. Document formatted into pages; contains xii, 156 p. : maps (some col.) Includes abstract. Includes bibliographical references (p. 151-156).
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Estrutura das comunidades de peixes na bacia do rio Iguatemi-MSSúarez, Yzel Rondon [UNESP] January 2004 (has links) (PDF)
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suarez_yr_dr_rcla.pdf: 1415743 bytes, checksum: da926441413780941456f718c30f0694 (MD5) / Com o objetivo de descrever os principais padrões de organização das comunidades de peixes realizamos amostragens trimestrais em diferentes ambientes da bacia do rio Iguatemi. Os dados de abundância e ocorrência das espécies foram submetidos a métodos uni e multivariados procurando verificar a existência de um padrão longitudinal e sazonal para essas comunidades. Encontramos 72 espécies de peixes em toda a bacia, constatamos que existe variação longitudinal estatisticamente significativa na composição de espécies para os rios Jogui e Iguatemi, mas não existe variação sazonal. A diversidade de espécies não variou longitudinalmente no rio Iguatemi, mas sim no rio Jogui. As espécies apresentam um padrão determinístico de associação, com clara diferenciação ente espécies de riachos de cabeceira e de rios de maior volume. Existem diferenças significativas na composição de espécies entre os ambientes estudados. Contudo estas diferenças não foram relacionadas às características selecionadas dos ambientes estudados. / This paper aims to describe the main patterns of fish communities organization. Tree-monthly samples were realized in different environments of Iguatemi River basin. The abundance and occurrence of species were submitted to uni and multivariate statistical methods in order to verify the existence of a longitudinal and seasonal pattern in fish communities. Seventy two fish species were collected in all basin. We observed longitudinal differences in species composition for Jogui and Iguatemi Rivers. However we did not detect any seasonal variation. The species diversity did not show statistically significant longitudinal variation in Iguatemi River, contrary to Jogui River. Fish species presented a deterministic association pattern in both rivers, with a clear differentiation between headwaters and downstream. Albeit we detected a significant difference in species composition in the whole basin it is not correlated to selected environmental characteristics.
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Estudo ecossistêmico em uma vereda na região de Três Marias: com base em indicadores limnológicos e ecomorfológicosLópez, Cristiane Machado de [UNESP] 25 September 2009 (has links) (PDF)
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lopez_cm_dr_jabo.pdf: 22316757 bytes, checksum: f48afacc1bb98b5495a7a02038c3042b (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / O principal objetivo deste trabalho foi caracterizar a vereda Curral das Éguas, por meio da investigação de seus recursos naturais, o qual integra um conjunto de indicadores limnológicos e ecomorfológicos. A vereda está inserida na cabeceira de um afluente da bacia do rio São Francisco, situada na região de Três Marias/MG. As amostragens foram realizadas em cinco períodos representativos do ciclo hidrológico. Os recursos disponíveis nos habitats foram observados em quatro trechos selecionados com base nas diferenciações das zonas funcionais do sistema, ao longo do gradiente longitudinal da vereda. O protocolo de avaliação foi aplicado com o intuito de quantificar os atributos ecofísicos do leito, das margens e do ambiente no entorno. Os aspectos limnológicos foram pesquisados de forma concomitante por intermédio das variáveis físicas, químicas e biológicas das águas. As principais fontes de carbono orgânico foram estudadas por intermédio do potencial de lixiviação das macrófitas dominantes e das frações foliares de Mauritia flexuosa (buriti), sendo o aporte de carbono orgânico dissolvido mapeado nos trechos de amostragem. A composição, riqueza e abundância das comunidades de microinvertebrados fitófilos (Protista, Rotifera e Crustacea) foram pesquisadas e a distribuição espaço temporal dos organismos zooperifíticos descrita numa abordagem interativa com as variáveis limnológicas e ecofísicas da vereda / The main purpose of this work was to characterize the vereda Curral das Éguas in its state of conservation, by means of inquiring its natural resources, which integrate a set of limnological and ecomorfological indicators. This vereda is inserted in the headspring affluent of the São Francisco river basin, localized in the region of Três Marias, Minas Gerais State. For that intention were selected four stretches, based in the different functional zones, through the longitudinal gradient of vereda system. The samplings were collected in five representative periods of hidrological cycle, based on resource available in the habitat. The evaluation protocol was applied to semiquantify the physical attributes, and assess habitat quality of the stream bed, margins and surrounding environment. The limnological aspects had been searched through the physical, chemical and biological variables of the water. The principal sources of organic carbon had been studied by means leaching potential of the dominant macrophytes and buritis (Mauritia flexuosa) fractions of the leaves. The contributions of organic carbon dissolved were mapped in the sampling stretches. The composition, richness and abundance of microinvertebrates phytophylous community (Protista, Rotifera and Crustacea) were searched, and the spatial temporal distribution of the organisms, described in a interative abordation with the ecophysical and liminological variables
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Transfert de particules des versants aux masses d'eau sur le bassin Loire-Bretagne / Particle transfer from hillslope to water system in the Loire and britany river basinGay, Aurore 21 September 2015 (has links)
L’érosion et la redistribution des particules détachées représentent un enjeu environnemental, sociétal et économique majeur. Afin de mettre en place des mesures de protection, il est nécessaire d’identifier et quantifier les sources et puits de sédiments ainsi que leur dynamique spatiale et temporelle. L’objectif de cette thèse est donc de dresser le bilan sédimentaire d’un large bassin versant (Loire Bretagne, 155 000 km2) aux paysages contrastés. Sur les versants, les particules détachées issues des différentes sources (érosion diffuse, concentrée, mouvements de masse) représentent un apport de 1.5 * 107 t.an−1 (contribution respective au stock : 82.4%, 12.9%, 4.7%). La prise en compte de la distribution spatiale des processus mis en jeu dans le transfert particulaire et des caractéristiques du site d’étude (ruissellement par saturation en zone de plaine et présence de haies) dans un indice qualitatif permet d’évaluer la connectivité des versants. L’érosion de berge contribue également au stock sédimentaire à hauteur de 6.9 * 105 t.an−1. Au final, seuls 5% des particules détachées, toutes sources confondues, sont transportées jusqu’à l’exutoire du bassin versant et témoignent du fort taux de dépôt au sein du bassin. En parallèle, une valorisation de la base de données des éléments dissous permet de montrer l’importance des flux sédimentaires exportés sous forme dissoute (~ 90% des exports totaux). La représentation de l’ensemble de ces résultats à différentes résolutions spatiales permet de développer une approche qualitative du transfert particulaire et d'identifier les zones à risque. / Erosion and particles redistribution represent major environmental, societal and economic issues. To adopt protection measures, it is essential to identify and quantify sources and sinks of sediment and their spatial and temporal dynamic. The aim of this work is thus to establish a sediment budget for a large river basin (Loire and Brittany river basin 155,000 km2) with contrasted landscapes. On hillslopes, detached particles from the miscellaneous form of erosion (sheet and rill erosion, gullies and mass movements) represent a supply of 1.5 * 107 t.yr−1 (contribution to the stock of 82.4%, 12.9%, and 4.7% respectively). The consideration of the spatial distribution of processes involved in sediment transport and the characteristics of the study site (soil saturation and presence of hedgerows) in a qualitative landscape-based index allows us to assess the hillslope connectivity. Bank erosion also participates in the sediment budget with 6.9 * 105 t.yr−1 of material provided to the river network. In the end, only 5% of detached particles, from all sources of sediment, reach the basin outlet indicating a substantial deposition on the way from source to outlet. In parallel, the use of the database of dissolved elements allows us to highlight the importance of the dissolved sediment fluxes ( 90% of the total exports of the Loire river). The presentation of all results at different spatial scales permits to provide a qualitative approach of sediment source-to-sink transfers and to identify hotspots of erosion and transfers.
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Interfaces da gestão integrada de recursos hídricos e da zona costeira : uma aplicação na bacia hidrográfica do rio TramandaíLoitzenbauer, Ester January 2010 (has links)
Como um ambiente de transição e de grande concentração de atividades humanas, a zona costeira é uma das áreas de maior estresse ambiental do mundo. Esta concentração gera demanda por água para os mais diversos usos. A principal fonte de água na zona costeira é a bacia hidrográfica. O oceano, o estuário e as bacias hidrográficas interagem, formando um contínuo fluvial-marinho costeiro. Quando as atividades antrópicas retiram água doce da bacia, podem estar limitando a disponibilidade hídrica numa região costeira, pois a diminuição da afluência de água doce aos estuários aumenta a área de influência da salinidade. Esta dinâmica da salinidade em função da afluência de água doce pode ser compreendida através de um modelo de balanço de massa. Após compreender esta dinâmica, subsídios podem ser propostos para a gestão de um ambiente costeiro, visando prevenir possíveis limitações da disponibilidade de água doce devido à salinização das águas. Com base no artigo 3º da Política Nacional de Recursos Hídricos (PNRH), que prevê que a gestão dos recursos hídricos deve ser integrada com a das zonas costeiras e dos sistemas estuarinos, propõem-se a compreensão do balanço de salinidade como uma ferramenta para a gestão de recursos hídricos na zona costeira. Utilizando um modelo matemático integrado com geoprocessamento, como método de compreensão da dinâmica da salinidade, realiza-se um estudo de caso na bacia do Rio Tramandaí. Assim, subsídios para a gestão são discutidos, utilizando os instrumentos da PNRH e do Plano Nacional de Gerenciamento Costeiro (PNGC), para a bacia em questão. Com o modelo foram testados três cenários: dois de mudanças climáticas, seca e cheia, e um de aumento da área irrigada de arroz, visto que é a principal atividade econômica da bacia, juntamente com o abastecimento público. O resultado dos cenários atesta que a influência da salinidade é sentida até a Lagoa do Passo, limite interior do estuário. Observa-se que para os cenários de escassez hídrica, de seca e aumento na demanda de água, a salinidade do estuário aumenta, principalmente na Lagoa do Passo. No cenário de cheia, a salinidade diminuiu. Com o modelo de balanço de salinidade, observou-se a aplicabilidade dos instrumentos da PNRH e do zoneamento ecológico-econômico costeiro (ZEEC) do PNGC. O enquadramento, a salinidade pode ser introduzida como parâmetro a ser monitorado, pois compromete o uso dos recursos hídricos, além de ser integrada com o ZEEC que já existe na bacia. A outorga pode ser estabelecida, para manter uma vazão mínima que impeça a intrusão salina indesejada. A cobrança pode ser usada como meio de induzir os orizicutores a utilizar métodos de irrigação mais eficientes. A dinâmica da salinidade se mostrou uma ferramenta eficaz para gestão de recursos hídricos na zona costeira, por funcionar como um indicador da disponibilidade hídrica. No caso específico da bacia do Rio Tramandaí, esta ferramenta deve ser utilizada no nível do comitê de bacia (já existente), para resolver questões ligadas com a intrusão salina e a interação bacia – oceano. / As a transition environment of great human activities concentration, the coastal zone is an area of major environmental stress in the world. This merger creates a demand of water for different uses. The main source of water in this area is the river basin. The ocean, the estuary and the watersheds interact forming a continuous freshwater – coastal environment. When human activities remove freshwater from the basin they may be limiting the availability of water in a coastal region, since reduced freshwater inflow to estuaries increases the area of influence of the salinity. This dynamic function of salinity and fresh water inflow can be understood through a mass balance. Technical inputs can be proposed to manage a coastal environment, preventing possible limitations on the availability of fresh water due to the salinity. The article 3 of the National Water Resources Policy (PNRH) said that the management of water resources must be integrated with the coastal and estuarine systems. Based on this assumption a methodology is proposed: the understanding of salinity balance as a tool for management of water resources in the coastal zone. Using a mathematical model integrated with GIS for understanding the salinity dynamics a case study is done on the Tramandaí river basin. For this basin, management practices and technical inputs are discussed using the tools of PNRH and the National Coastal Management Plan (PNGC). With the model we tested three scenarios: two climate change, drought and flood, and an increased area of irrigated rice, as it is the main economic activity of the basin along with public provision. The result of the scenarios shows that the influence of salinity is felt unto the Passo Lagoon, the inner edge of the estuary. It is observed that in the water scarcity scenarios, drought and increased demand for water, the salinity of the estuary rises, especially in the Passo Lagoon. In the scenario of flood the salinity decreased. Using the salinity balance model, it was observed the applicability of the tools of PNRH and the coastal ecological-economic zoning (ZEEC) of the PNGC. In the classification of water bodies the salinity may be introduced as a parameter to be monitored, because it jeopardizes the use of water resource. Also it can be integrated with the ZEEC that already exists in the basin. The grant of water resources use can be established to maintain a minimum flow to prevent the unwanted salt intrusion. The water use charges can be used as a mean of inducing rice farmers to use more efficient methods of irrigation. The dynamics of salinity proved to be an effective tool for managing water resources in the coastal zone, acting as an indicator of water availability. In the specific case of Tramandaí river basin, this tool should be used in the basin committee level to solve issues related to salt intrusion and basin - ocean interaction.
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