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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.
1

Modelagem hidrolÃgica da bacia hidrogrÃfica do rio granjeiro â Crato-CE: composiÃÃo do cenÃrio atual e simulaÃÃes de uso e ocupaÃÃo do solo / Hydrological modeling of river basin farmer - Crato-CE: composition of the present scenario and simulations for use and occupation of land

Adolfo Ãtila Cabral Moreira 23 August 2013 (has links)
nÃo hà / O trabalho apresenta um modelo hidrolÃgico inÃdito para a bacia hidrogrÃfica do rio Granjeiro (BHG), com uma Ãrea de contribuiÃÃo de 18,54 kmÂ, altitude variando de 399 a 953 metros acima do nÃvel do mar, localizada no municÃpio do Crato, regiÃo sul do estado do CearÃ, regiÃo de grande relevÃncia econÃmica no estado, destacando-se o comÃrcio e o turismo. O modelo foi desenvolvido utilizando o software HEC-HMS do Centro de Engenharia HidrolÃgico (CEIWR-HEC), do corpo de engenheiros do exercito dos Estados Unidos da AmÃrica (USACE). A metodologia utilizada foi composta por trÃs partes. A primeira parte tratou de extrair os dados geogrÃficos, fÃsicos e hidrolÃgicos, utilizando modelos digitais de elevaÃÃo, imagens de satÃlites e mapas temÃticos de caracterizaÃÃo territorial do estado do CearÃ, por meio do software ArcGIS e sua extensÃo HEC-GeoHMS, para exportÃ-los para o HEC-HMS. A segunda parte se concentrou na construÃÃo dos hietogramas, utilizando a equaÃÃo de chuva do municÃpio do Crato e o mÃtodo dos blocos alternados. E por fim, na terceira etapa foi simulado o escoamento superficial, provocado por chuvas com vÃrios tempos de retornos, tanto para o cenÃrio atual, quanto para vÃrios cenÃrios fictÃcios da BHG, utilizando o mÃtodo desenvolvido pelo ServiÃo de ConservaÃÃo do Solo (SCS) do Departamento de Agricultura dos Estados Unidos (USDA), conhecido como o modelo SCS. Verificou-se que as Sub-bacias SB4, SB5 e SB9 contribuem com 46% do escoamento total no exutÃrio, alÃm de um crescimento de ocupaÃÃo da BHG em 15%, praticamente dobrarà a probabilidade de cheias no canal do rio Granjeiro, enquanto a diminuiÃÃo desta ocupaÃÃo em 15%, praticamente reduz a possibilidade de cheias no canal do rio Granjeiro pela metade. Contudo, à importante frisar, que o modelo hidrolÃgico apresentado à o primeiro modelo elaborado para a BHG, dando aos gestores municipais do Crato a possibilidade de estudar a construÃÃo de obras hidrÃulicas para contenÃÃo das cheias, alÃm de implementaÃÃo de polÃticas pÃblicas de ocupaÃÃo das Ãreas em contidas na BHG, com o objetivo de reduzir as enchentes ocorridas no canal do rio Granjeiro. / The paper proposes a novel model for hydrological river basin Granjeiro (BHG), with a contribution area of 18.54 kmÂ, altitude ranging 399-953 meters above sea level, located in the county of Crato, southern the state of Cearà of great economic importance in the state, especially trade and tourism. The model was developed using the software HEC-HMS Hydrologic Engineering Center (CEIWR-HEC), the engineer corps of the army of the United States (USACE). The methodology used was composed of three parts. The first part dealt with data extraction geographic, physical and hydrological using digital elevation models, satellite images and thematic maps of territorial characterization of the state of CearÃ, through the ArcGIS software and its extension HEC-GeoHMS to export them for HEC-HMS. The second part focused on building the hietogramas, using the equation of rain Crato and the method of alternating blocks. And finally, the third step was simulated runoff caused by rain several times with returns, both for the current scenario, as for several fictional scenarios BHG, using the method developed by the Soil Conservation Service (SCS) Department of Agriculture (USDA), known as the SCS model. It was found that the sub-basins SB4, SB5 and SB9 contribute 46% of the total flow in river mouth, end an increase in occupancy of BHG 15%, nearly double the likelihood of flooding in the river channel Granjeiro, while this occupation decreased by 15 %, almost reduces the likelihood of flooding in the river channel Granjeiro by half. However, it is important to note that the hydrological model presented is the first model designed for BHG, giving municipal managers Crato the possibility to study the construction of hydraulic containment of floods, as well as implementation of policies of occupation of areas contained in BHG, with the goal of reducing the flooding that occurred in the river channel Granjeiro.
2

Surface water hydrologic modeling using remote sensing data for natural and disturbed lands

Muche, Muluken Eyayu January 1900 (has links)
Doctor of Philosophy / Department of Biological & Agricultural Engineering / Stacy L. Hutchinson / The Soil Conservation Service-Curve Number (SCS-CN) method is widely used to estimate direct runoff from rainfall events; however, the method does not account for the dynamic rainfall-runoff relationship. This study used back-calculated curve numbers (CNs) and Normalized Difference Vegetation Index (NDVI) to develop NDVI-based CNs (CN[subscript]NDV) using four small northeastern Kansas grassland watersheds with average areas of 1 km² and twelve years (2001–2012) of daily precipitation and runoff data. Analysis indicated that the CN[subscript]NDVI model improved runoff predictions compared to the SCS-CN method. The CN[subscript]NDVI also showed greater variability in CNs, especially during growing season, thereby increasing the model’s ability to estimate relatively accurate runoff from rainfall events since most rainfall occurs during the growing season. The CN[subscript]NDVI model was applied to small, disturbed grassland watersheds to assess the model’s ability to detect land cover change impact for military maneuver damage and large, diverse land use/cover watersheds to assess the impact of scaling up the model. CN[subscript]NDVI application was assessed using a paired watershed study at Fort Riley, Kansas. Paired watersheds were identified through k-means and hierarchical-agglomerative clustering techniques. At the large watershed scale, Daymet precipitation was used to estimate runoff, which was compared to direct runoff extracted from stream flow at gauging points for Chapman (grassland dominated) and Upper Delaware (agriculture dominated) watersheds. In large, diverse watersheds, CN[subscript]NDVI performed better in moderate and overall flow years. Overall, CN[subscript]NDVI more accurately simulated runoff compared to SCS-CN results: The calibrated model increased by 0.91 for every unit increase in observed flow (r = 0.83), while standard CN-based flow increased by 0.506 for every unit increase in observed flow (r = 0.404). Therefore, CN[subscript]NDVI could help identify land use/cover changes and disturbances and spatiotemporal changes in runoff at various scales. CN[subscript]NDVI could also be used to accurately estimate runoff from precipitation events in order to instigate more timely land management decisions.
3

Simulação e gestão da disponibilidade hídrica em bacia hidrográfica representativa do bioma Cerrado / Simulation and management of water availability in basin representative of the cerrado biome

Gotardo, Jackeline Tatiane 10 February 2011 (has links)
Made available in DSpace on 2017-07-10T19:25:24Z (GMT). No. of bitstreams: 1 Jackeline Gotardo parte 1.pdf: 5941044 bytes, checksum: e7a46324b06508bcbeab16411c56e75d (MD5) Previous issue date: 2011-02-10 / The simulation study of water availability and management of the basin was addressed in two ways. First estimate the water demand in climatological experimental catchment representative of the Savannah. Defined by the difference in the occurrence of potential evapotranspiration and precipitation minimal likely to occur on a scale ten days. In the estimation of potential evapotranspiration compared to the empirical equations of the methods Blaney-Criddle, Hargreaves, ASCE Penman-Monteith, Penman, Priestley-Taylor method with the standard Penman-Monteith FAO 56. The method presented Blaney-Criddley is recommended when there is limited availability of climatological data. To estimate the probability distribution used the gamma distribution for the time series of precipitation and evapotranspiration and precipitation time series with zero values, we used the incomplete gamma function. The adhesion of the estimated probabilities to the observed data was verified by testing, non-parametric Kolmogorov-Smirnov test, with significance level (α-0, 05) which fitted well the model distributions. The occurrence of precipitation and evapotranspiration decendial likely P (X ≥ x) for different probability levels showed drought periods of ten days between 4:32, with critical values 25-39 mm, on a scale ten days, the months from May to September. In a second stage it was considered the the reservoir of soil water management and proposes a model allowing to calculate the irrigation water demand of crops of beans and corn planting dates in two different in drought and rainy. The bowl was hydrology by the method of the turn number (CN). Simulated the water demand and availability required in ascertaining what is the risk of meeting the irrigated area. The proposed model was effective for water management in the basin throughout the year. It was found that corn and beans require different amounts of water throughout the year, and that optimizing the additional water demand is a management tool able to minimize conflicts over water use. hydrology of the basin presents risks of not having met the demand required in the dry period is necessary to establish infraestrurura water for water storage / O estudo da simulação e da gestão da disponibilidade hídrica da bacia foi abordado de duas formas. Primeiramente, foi estimada a demanda hídrica climatológica em bacia hidrográfica experimental representativa do Cerrado, definido pela diferença da ocorrência da evapotranspiração potencial e precipitação mínima provável de ocorrer, em escala decendial. Na estimativa da Evapotranspiração potencial comparou-se as equações empíricas dos métodos Blaney-Criddle, Hargreaves, Penman-Monteith ASCE, Penman, Priestley-Taylor com o método padrão de Penman-Monteith FAO 56. O método Blaney- Criddley é recomendado quando há limitação na disponibilidade de dados climatológicos. Para estimativa da distribuição de probabilidade, utilizou-se a distribuição gama para a série histórica de precipitação e evapotranspiração e, para série histórica de precipitação com valores nulos, utilizou-se a função gama incompleta. A aderência das probabilidades estimadas aos dados observados foi verificada através do teste, não-paramétrico, de Kolmogorov-Smirnov, com nível de significância (􀄮-0,05), o qual ajustou-se bem aos modelos de distribuições. A ocorrência de precipitação e evapotranspiração decendial provável P (X 􀂕 x) para diferentes níveis de probabilidades demonstrou déficit hídrico entre os decêndios 4 e 32, apresentando valores críticos de 25 a 39 mm, em escala decendial, nos meses de maio a setembro. Em um segundo momento, considerou-se o reservatório de água do solo propondo um modelo de manejo de irrigação permitindo calcular a demanda hídrica das culturas de feijão e milho em duas datas de plantio diferentes em período de seca e chuvoso. O comportamento hidrológico da bacia foi através do método do número da curva (CN). Simulou-se a demanda hídrica requerida e a disponibilidade, averiguando qual o risco de atender a área irrigada. O modelo proposto foi eficaz para a gestão hídrica da bacia ao longo do ano. Verificou-se que culturas de milho e feijão requerem diferentes quantidades de água ao longo do ano e que a otimização pela demanda hídrica complementar é um instrumento de gestão capaz de minimizar conflitos pelo uso da água. O comportamento hidrológico da bacia apresenta riscos de não ter a demanda requerida atendida no período seco, sendo necessário a implantação de infraestrutura hídrica para armazenamento de água
4

Simulação e gestão da disponibilidade hídrica em bacia hidrográfica representativa do bioma Cerrado / Simulation and management of water availability in basin representative of the cerrado biome

Gotardo, Jackeline Tatiane 10 February 2011 (has links)
Made available in DSpace on 2017-05-12T14:48:47Z (GMT). No. of bitstreams: 1 Jackeline Gotardo parte 1.pdf: 5941044 bytes, checksum: e7a46324b06508bcbeab16411c56e75d (MD5) Previous issue date: 2011-02-10 / The simulation study of water availability and management of the basin was addressed in two ways. First estimate the water demand in climatological experimental catchment representative of the Savannah. Defined by the difference in the occurrence of potential evapotranspiration and precipitation minimal likely to occur on a scale ten days. In the estimation of potential evapotranspiration compared to the empirical equations of the methods Blaney-Criddle, Hargreaves, ASCE Penman-Monteith, Penman, Priestley-Taylor method with the standard Penman-Monteith FAO 56. The method presented Blaney-Criddley is recommended when there is limited availability of climatological data. To estimate the probability distribution used the gamma distribution for the time series of precipitation and evapotranspiration and precipitation time series with zero values, we used the incomplete gamma function. The adhesion of the estimated probabilities to the observed data was verified by testing, non-parametric Kolmogorov-Smirnov test, with significance level (α-0, 05) which fitted well the model distributions. The occurrence of precipitation and evapotranspiration decendial likely P (X ≥ x) for different probability levels showed drought periods of ten days between 4:32, with critical values 25-39 mm, on a scale ten days, the months from May to September. In a second stage it was considered the the reservoir of soil water management and proposes a model allowing to calculate the irrigation water demand of crops of beans and corn planting dates in two different in drought and rainy. The bowl was hydrology by the method of the turn number (CN). Simulated the water demand and availability required in ascertaining what is the risk of meeting the irrigated area. The proposed model was effective for water management in the basin throughout the year. It was found that corn and beans require different amounts of water throughout the year, and that optimizing the additional water demand is a management tool able to minimize conflicts over water use. hydrology of the basin presents risks of not having met the demand required in the dry period is necessary to establish infraestrurura water for water storage / O estudo da simulação e da gestão da disponibilidade hídrica da bacia foi abordado de duas formas. Primeiramente, foi estimada a demanda hídrica climatológica em bacia hidrográfica experimental representativa do Cerrado, definido pela diferença da ocorrência da evapotranspiração potencial e precipitação mínima provável de ocorrer, em escala decendial. Na estimativa da Evapotranspiração potencial comparou-se as equações empíricas dos métodos Blaney-Criddle, Hargreaves, Penman-Monteith ASCE, Penman, Priestley-Taylor com o método padrão de Penman-Monteith FAO 56. O método Blaney- Criddley é recomendado quando há limitação na disponibilidade de dados climatológicos. Para estimativa da distribuição de probabilidade, utilizou-se a distribuição gama para a série histórica de precipitação e evapotranspiração e, para série histórica de precipitação com valores nulos, utilizou-se a função gama incompleta. A aderência das probabilidades estimadas aos dados observados foi verificada através do teste, não-paramétrico, de Kolmogorov-Smirnov, com nível de significância (􀄮-0,05), o qual ajustou-se bem aos modelos de distribuições. A ocorrência de precipitação e evapotranspiração decendial provável P (X 􀂕 x) para diferentes níveis de probabilidades demonstrou déficit hídrico entre os decêndios 4 e 32, apresentando valores críticos de 25 a 39 mm, em escala decendial, nos meses de maio a setembro. Em um segundo momento, considerou-se o reservatório de água do solo propondo um modelo de manejo de irrigação permitindo calcular a demanda hídrica das culturas de feijão e milho em duas datas de plantio diferentes em período de seca e chuvoso. O comportamento hidrológico da bacia foi através do método do número da curva (CN). Simulou-se a demanda hídrica requerida e a disponibilidade, averiguando qual o risco de atender a área irrigada. O modelo proposto foi eficaz para a gestão hídrica da bacia ao longo do ano. Verificou-se que culturas de milho e feijão requerem diferentes quantidades de água ao longo do ano e que a otimização pela demanda hídrica complementar é um instrumento de gestão capaz de minimizar conflitos pelo uso da água. O comportamento hidrológico da bacia apresenta riscos de não ter a demanda requerida atendida no período seco, sendo necessário a implantação de infraestrutura hídrica para armazenamento de água
5

Modelling of nonpoint source pollution in the Kuils River Catchment, Western Cape - South Africa

Ayuk, James Ayuk January 2008 (has links)
>Magister Scientiae - MSc
6

Modelling of nonpoint source pollution in the Kuils River catchment, Western Cape - South Africa

Ayuk, James Ayuk January 2008 (has links)
>Magister Scientiae - MSc / The Kuils River Catchment is an urban river catchment that forms part of the larger Kuils-Eerste River system draining the eastern half of the Cape Metropolitan Authority area and Stellenbosch Municipality. Rapid urbanisation has resulted in the encroachment of residential and industrial areas into the river system through channelization and sewage disposal. This research project intends to assess the quality of surface runoff in the Kuils River catchment and determining non-point source pollutant loading rates in the catchment using GIS-based modelling. The study results show how modelled potential sources of surface runoff and NPS pollutants using desktop GIS analysis tools in a sequential process that involved different levels of software applications could explain the characteristics of the catchment. With the help of the Expected Mean Concentration (EMC) values associated with surface runoff from land use/covers, NPS pollutant loads were assessed downstream towards the Kuils River Catchment outlet using the Nonpoint Source Pollution and Erosion Comparison Tool (N-SPECT) based in ArcGIS. The outputs from this model consist of predicted annual pollutant loading (mg/mvyear) for each Kuils-Eerste River that occurs in the catchment. The results have shown clearly the spatial distribution of sources of particular pollutants in the catchment. Further or advanced processing knowhow with this model might provide far reaching insights into the problem and it is however recommended that these results produced using N-SPECT be compared to those of other hydrologic models using the same inputs.

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