Os reservatórios são causas significativas de alterações no ciclo hidrossedimentológico e, ao mesmo tempo, sofrem grandes impactos por efeitos de retroalimentação. A intensificação do processo de deposição de sedimentos com a presença de reservatórios gera impactos no ecossistema da bacia e no próprio reservatório, que pode ter sua capacidade reduzida pelo assoreamento. Neste contexto, a Agência Nacional de Águas (ANA) estabelece orientações para a atualização da curva Cota x Área x Volume (CAV), por meio da Resolução Conjunta ANEEL/ANA nº 03 de 2010, que visa monitorar as condições de assoreamento dos reservatórios; e pode subsidiar o gerenciamento dos recursos da bacia hidrográfica. Com isso, o objetivo deste estudo é avaliar o assoreamento e gerar nova curva CAV para o reservatório do Lobo – Itirapina/SP – a partir da comparação entre as batimetrias realizadas nos anos 2010 e 2018. O levantamento batimétrico de 2018 seguiu as recomendações da resolução citada, bem como os procedimentos realizados em 2010, a fim de se obter uma comparação entre dados de metodologias coincidentes. A coleta de dados foi feita a partir de 3 principais dispositivos: ecobatímetro, Differential Global Positioning System (DGPS) Real Time Kinematic (RTK) e software de levantamento hidrográfico. Em seguida, o processamento dos dados gerou mapas indicadores de áreas de assoreamento e volumes correspondentes. A atualização da curva CAV a partir dos dados finais encontrados mostra que o reservatório não sofreu perdas significantes de volume, sendo o volume em 2010 igual a 23,9 hm3 e, em 2018, 23,8 hm3, correspondendo a uma perda de 0,4% em volume. Diferentes ferramentas utilizadas no processamento dos dados possibilitaram a discretização da comparação entre os volumes, sendo possível identificar o volume de 2018 que se encontra abaixo ou acima da superfície de referência 2010. O volume localizado abaixo da referência representa 1,3% do volume total e o volume localizado acima, que indica áreas assoreadas, representa 1,7% do volume total. Assim, este trabalho pode contribuir com considerações sobre diversos fatores que podem alterar resultados de comparações de batimetrias, seguindo esta metodologia. As considerações sobre a configuração dos equipamentos e sobre as recomendações da Resolução nº 03 de 2010 são relevantes na busca por resultados cada vez mais precisos na análise do assoreamento de reservatórios. Logo, espera-se que este resultado possa servir como contribuição em futuros estudos relacionados à análise de assoreamento por meio de comparação de batimetrias; e possa auxiliar o planejamento e gestão dos recursos hídricos na bacia hidrográfica do ribeirão do Lobo. / Reservoirs are significant causes of changes in the hydrosedimentological cycle and, at the same time, suffer great impacts by feedback effects. The intensification of the sediment deposition process in the presence of reservoirs generates impacts on the basin ecosystem and on the reservoir itself, which may have its capacity reduced by silting. In this context, the National Water Agency (ANA) establishes guidelines for updating the Elevation x Area x Volume (CAV) curve, by means of ANEEL/ANA Joint Resolution No. 03 of 2010, which aims to monitor the silting conditions of reservoirs; and can support the management of river basin resources. The objective of this study was to evaluate the sedimentation and generate a new CAV curve for the Lobo reservoir - Itirapina/SP - from the comparison between the bathymetry performed in the years 2010 and 2018. The bathymetric survey of 2018 followed the recommendations of the resolution as well as the procedures carried out in 2010, in order to obtain a comparison between data from matching methodologies. The data collection was done with 3 main devices: Echo Sounder, Differential Global Positioning System (DGPS) Real Time Kinematic (RTK) and software for hydrographic survey. Then, the data processing generated maps indicating silting areas and corresponding volumes. The updating of the CAV curve with the final data found shows that the reservoir did not suffer significant losses of volume, since the volume in 2010 equals to 23.9 hm3 and, in 2018, to 23.8 hm3, corresponding to a loss of 0.4% in volume. Different tools used in the data processing allowed the discretization in the comparison between the volumes, and it is possible to identify the volume of 2018 that is below or above the 2010 reference surface. The volume located below the reference represents 1.3% of the total volume and the volume located above, which indicates silted areas, represents 1.7% of the total volume. Thus, this work can contribute with considerations about several factors that can alter results of comparisons of bathymetry, following this methodology. The considerations on the configuration of the equipment and on the recommendations of the Resolution nº 03 of 2010 are relevant in the search for more precise results in the analysis of reservoir siltation. Therefore, it is expected that this result may serve as a contribution for future studies related to the silting analysis by comparing bathymetry; and can assist in the planning and management of water resources in the catchment area of the Lobo stream.

Orientador: Mauricio Galo / Resumo: Um Levantamento Hidrográfico (LH) tem como principal meta a obtenção de dados para a edição e atualização de documentos náuticos, estes, voltados à segurança das atividades de navegação. Objetivando padronizar parâmetros de incerteza das cartas náuticas, a Organização Hidrográfica Internacional (OHI) define níveis mínimos de confiança para diferentes ordens. A sugestão dessas especificações foi internalizada pela Marinha do Brasil, responsável pela produção das cartas náuticas brasileiras, na NORMAM-25. Um desses parâmetros é a Incerteza Vertical Total máxima permitida, um indicador de qualidade da medição da profundidade. A informação de profundidade influencia no calado máximo permitido a uma embarcação para transitar em uma região com segurança, o que pode impactar inclusive nas limitações de transações comerciais em terminais portuários, uma vez que as profundidades estimadas com acurácia potencializam os parâmetros de operação dos portos. Por se tratar de um ambiente dinâmico, seja por ação da própria natureza ou devido a atividades antrópicas, a atualização de uma carta náutica deve ser uma preocupação constante. Como complemento à tradicional técnica de levantamento por meio de um ecobatímetro acoplado a embarcações, há a opção de se realizar um LH com o emprego da tecnologia LiDAR (Light Detection And Ranging) a partir de aeronaves, por meio de um aerolevantamento batimétrico por LiDAR (ALB – Airborne LASER Bathymetry), que operam com pulsos LASER na região verde do e... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: A Hydrographic Survey (HS) has as main goal to obtain data for editing and updating nautical documents, these, focused on the safety of navigation. In order to establish a standard of uncertainty parameters for nautical charts, the International Hydrographic Organization (IHO) defines minimum levels of confidence for different orders. The suggestion of these specifications was acknowledged by the Brazilian Navy, institution responsible to produce Brazilian nautical charts, as described in NORMAM-25. One such parameter is the maximum allowed Total Vertical Uncertainty, a quality indicator of the depth measurement. Depth information influences the maximum operational draft for a vessel to safely travel in a region, causing impact on port operations and limiting the commercial transactions. Accurately estimated depths enhance the operational parameters of the ports. Due to the aim of representing a dynamic environment, whether as consequence of the action of nature itself or because of anthropic activities, updating a nautical chart must be a constant concern. As a complement to the traditional survey technique conducted with a boat-coupled echosounder, there is the option of performing a HS using LiDAR (Light Detection And Ranging) technology from aircraft, through LiDAR aerial bathymetry (ALB - Airborne LASER Bathymetry), which operate with LASER pulses in the green region of the electromagnetic spectrum. Considering these points, this work analyzed the differences between the... (Complete abstract click electronic access below) / Mestre

Knowledge of water depth is a crucial for planning military amphibious operations. Bathymetry from remote sensing with multispectral or hyperspectral imagery provides an opportunity to acquire water depth data faster than traditional hydrographic survey methods without the need to deploy a hydrographic survey vessel. It also provides a means of collecting bathymetric data covertly. This research explores two techniques for deriving bathymetry and assesses them for use by those involved in providing support to military operations. To support this aim a fieldwork campaign was undertaken in May, 2000, in northern Queensland. The fieldwork collected various inherent and apparent water optical properties and was concurrent with airborne hyperspectral imagery collection, space-based multispectral imagery collection and a hydrographic survey. The water optical properties were used to characterise the water and to understand how they affect deriving bathymetry from imagery. The hydrographic data was used to assess the performance of the bathymetric techniques. Two methods for deriving bathymetry were trialled. One uses a ratio of subsurface irradiance reflectance at two wavelengths and then tunes the result with known water depths. The other inverts the radiative transfer equation utilising the optical properties of the water to derive water depth. Both techniques derived water depth down to approximately six to seven metres. At that point the Cowley Beach waters became optically deep. Sensitivity analysis of the inversion method found that it was most sensitive to errors in vertical attenuation Kd and to errors in transforming the imagery into subsurface irradiance reflectance, R(0-) units. Both techniques require a priori knowledge to derive depth and a more sophisticated approach would be required to determine water depth without prior knowledge of the area of interest. This research demonstrates that water depth can be accurately mapped with optical techniques in less than ideal optical conditions. It also demonstrates that the collection of inherent and apparent optical properties is important for validating remotely sensed imagery.

The Prairie Pothole Region (PPR) of North American contains millions of wetlands in shallow depressions that provide important hydrological and ecological functions. To assess and model these functions it is important to have accurate methods to quantify wetland water volume storage. Hayashi and van der Kamp (2000) developed equations suitable for calculating water volume in natural, regularly shaped wetlands when two coefficients are known. This thesis tested the robustness of their full and simplified volume (V) area (A) depth (h) methods to accurately estimate volume for the range of wetland shapes occurring across the PPR. Further, a digital elevation model (DEM) derived from light detection and ranging (LiDAR) data was used to extract the necessary data for applying the simplified V-A-h method at a broad spatial scale. Detailed topographic data were collected for 27 wetlands in the Smith Creek Research Basin and St. Denis National Wildlife Area, Saskatchewan that ranged in surface area shape. The full V-A-h method was found to accurately estimate volume (errors <5%) across wetlands of various shapes and is therefore suitable for calculating water storage in the variety of wetland shapes found in the PPR. Analysis of the simplified V-A-h method showed that the depression (p) and size (s) coefficients are sensitive to the timing of area and depth measurements and the accuracy of area measurements. Surface area and depth should be measured concurrently at two points in time to achieve volume errors <10%. For most wetlands this means measuring area and depth in spring when water levels are approximately 70% of hmax, and also in late summer prior to water depths dropping below 0.1 m. The wetted perimeter of the deepest water level must also be measured accurately to have volume errors less than 10%. Applying the simplified V-A-h method to a LiDAR DEM required GIS analysis to extract elevation contours that represent potential water surfaces. From these data the total wetland depth and s coefficient were estimated. Volume estimates through this LiDAR V-A-h method outperformed estimates from two volume-area equations commonly used in the PPR. Furthermore, the process to extract the wetland coefficients from the LiDAR DEM was automated such that storage could be estimated for the entire St. Denis National Wildlife Area. Applying the simplified V-A-h method according to the guidelines and data sources recommended here will allow for more accurate, time-effective water storage estimates at multiple spatial scales, thereby facilitating evaluation and modelling of hydrological and ecological functions.

The Prairie Pothole Region (PPR) of North American contains millions of wetlands in shallow depressions that provide important hydrological and ecological functions. To assess and model these functions it is important to have accurate methods to quantify wetland water volume storage. Hayashi and van der Kamp (2000) developed equations suitable for calculating water volume in natural, regularly shaped wetlands when two coefficients are known. This thesis tested the robustness of their full and simplified volume (V) area (A) depth (h) methods to accurately estimate volume for the range of wetland shapes occurring across the PPR. Further, a digital elevation model (DEM) derived from light detection and ranging (LiDAR) data was used to extract the necessary data for applying the simplified V-A-h method at a broad spatial scale. Detailed topographic data were collected for 27 wetlands in the Smith Creek Research Basin and St. Denis National Wildlife Area, Saskatchewan that ranged in surface area shape. The full V-A-h method was found to accurately estimate volume (errors <5%) across wetlands of various shapes and is therefore suitable for calculating water storage in the variety of wetland shapes found in the PPR. Analysis of the simplified V-A-h method showed that the depression (p) and size (s) coefficients are sensitive to the timing of area and depth measurements and the accuracy of area measurements. Surface area and depth should be measured concurrently at two points in time to achieve volume errors <10%. For most wetlands this means measuring area and depth in spring when water levels are approximately 70% of hmax, and also in late summer prior to water depths dropping below 0.1 m. The wetted perimeter of the deepest water level must also be measured accurately to have volume errors less than 10%. Applying the simplified V-A-h method to a LiDAR DEM required GIS analysis to extract elevation contours that represent potential water surfaces. From these data the total wetland depth and s coefficient were estimated. Volume estimates through this LiDAR V-A-h method outperformed estimates from two volume-area equations commonly used in the PPR. Furthermore, the process to extract the wetland coefficients from the LiDAR DEM was automated such that storage could be estimated for the entire St. Denis National Wildlife Area. Applying the simplified V-A-h method according to the guidelines and data sources recommended here will allow for more accurate, time-effective water storage estimates at multiple spatial scales, thereby facilitating evaluation and modelling of hydrological and ecological functions.

In March of 2000, March of 2001, and April of 2002, multibeam bathymetry and backscatter data were collected, which revealed several low-temperature hydrothermal submarine springs in the Mudhole Submarine Springs (MHSS) area that were investigated by SCUBA divers. High-resolution multibeam sonar provides a precise way of defining the geomorphology of the seafloor. The bathymetry data were used to understand (1) vent geomorphology and how it varied from vent to vent; (2) spatial patterns of active vents compared to extinct vents and known land springs identified by Kohout (1977) and Breland (1980); and (3) potential correlations between geochemical and geomorphological characteristics of the vents in the study area. SCUBA observations show that MHSS, Spring #3, New Spring, Northern Rusty, Rusty, and Near Rusty are active springs, while Dormant Spring and Sinister Spring were extinct or inactive at the time of the March 2001 cruise.During the April 2002 cruise the locations of Rusty Spring, New Spring and MHSS were confirmed. Two submarine springs, Creature Hole and Sparky Lee were also confirmed. Spring #3 is the deepest spring and Dormant Spring is the shallowest. There appears to be a rough spatial correlation between vents located on land and the vents on the seafloor, in which all known vents are either to the west or north of Lake Okeechobee. Vent distribution in the MHSS study area appears to correlate with the structural pattern of the local seafloor. Backscatter data and SCUBA observations show that fine to medium grain siliciclastic sediment bands overlie limestone hardbottom in a NE-SW orientation. Although vent geomorphologies are generally distinctive, vent activities generally correlate with the steepness of vent depressions.Most active vents had slopes of 6 degrees or greater, with the exception of Rusty Spring and Near Rusty Spring whose slopes ranged from 2.5 degrees and 6 degrees; whereas all the inactive vents had slopes of 5 degrees or less. Most active vents have "V"-shaped profiles versus the "U"-shaped profiles of most of the inactive vents. The inactive springs have shallower maximum depths and shallower ambient seafloor depths than the active vents.

Digital Elevation Models (DEM) are typically created through a variety of multi-step processes that are generally labour intensive. This thesis explores the trade-offs involved in automating these processes in order to produce a DEM at various resolutions, while minimizing artifacts and highlighting areas where artifacts or uncertainty may have been introduced. The iDEM system is a prototype design to automate the creation of customized DEM complete with a detailed audit-trail of metadata history. Originally conceived as a solution to creating DEM for tsunami modelling, iDEM is applicable to modelling any spherical surface. The proposed framework is highly generalizable in that it leverages existing applications in a plug-and-play manner, essentially integrating them into a new system. The creation of DEM in our prototype design utilizes an amalgamation of three existing fusion methods that allow tessellation without edge distortion and propagates data uncertainty for every DEM generated. The challenge of integrating data in different formats is tackled by automatically generating customized DEM based on the selection of any module providing data fusion techniques applied to the best measurements available. / Graduate

Tidally-influenced sandwaves are common coastal features present in various settings, including shipping channels. The main shipping channel in Tampa Bay under the Bob Graham Sunshine Skyway Bridge (a.k.a. the Skyway Bridge) contains such sandwave bedforms. Between the years 2000 and 2017, these bedforms have been surveyed with multibeam echosounders (MBES) on 21 occasions with ranging coverage and quality of returns. Surveys between 2000 and 2009 used a 300 kHz Kongsberg EM3000; surveys between 2015 and 2017 used a 400 kHz Reson Seabat 7125. For comparable surveys, bathymetry, backscatter, slope, curvature, planform curvature, and profile curvature maps were created and analyzed. Spectral analyses were completed on the same cross-section for usable surveys, providing a period and amplitude for the bedforms. Sediment samples were taken in September 2015 using a Shipek grab. The sediment samples were analyzed for grain size and carbonate content. A bottom-mounted ADCP recorded velocity data semi-continuously over the same time period. These data were analyzed in an effort to investigate the forcing mechanisms that influence the bedform morphology. Mean grain sizes in the shipping channel under the Skyway Bridge range from 0.01 φ (0.99 mm, coarse sand) to 1.55 φ (0.34 mm, medium sand). Calcium carbonate content ranges from 25% to 87%. The sediment sample site most representative of the sandwave bedforms has a mean grain size of 0.01 φ and a calcium carbonate content of 87%. The calculated mean current velocity required to initiate transport of the D50 and D84 grain size percentile of the representative sediment sample site is 0.70 m/s and 1.05 m/s, respectively. Analysis of the ADCP-recorded velocity data shows that the calculated D50 critical velocity is frequently reached by peak flood and peak ebb currents except during neap tides, while the D84 critical velocity is reached only intermittently, mostly during spring tides. Analysis of MBES backscatter shows similar spatial patterns in two larger MBES surveys in 2004 and 2015. Bathymetric analysis of the sandwaves shows consistent characteristics through time. Wave crest analysis reveals that bedforms migrate in both the ebb and flood directions. Spectral analysis shows primary wave spatial frequencies range from 0.13 m-1 to 0.22 m-1, and primary wave periods range from 4.5 m to 6.0 m. The predominant wavelength of sandwaves within the study area is about 5 m, with an average wave height of 0.47 m. The maximum wave height along the axial cross-section analyzed is 0.8 m, observed in April 2017. The sediments comprising the sandwave bedforms are likely winnowed by tidal currents resulting in larger grain size and carbonate content than other areas of the shipping channel and surrounding bay. Consistent patterns in MBES backscatter over time indicate that the sediment distribution pattern in the study area have not significantly changed. The size and shape of the bedforms in the shipping channel beneath the Skyway Bridge are have been in a quasi-dynamic equilibrium over the past 13 years. The bedforms are shown to migrate in both the ebb and flood directions despite an average faster ebb current velocity than a flood current velocity. More frequent and consistent MBES surveys as well as more continuous ADCP data availability would allow for better understanding of sediment transport via bedform migration in tidally-influenced environments.

Recent advances in through-water photogrammetry and optical imagery indicate that accurate, continuous bathymetric mapping may be possible in shallow, clear streams. This research directly compares the ability of through-water photogrammetry and spectral depth approaches to extract water depth for monitoring fish habitat. Imagery and cross sections were collected on a 140 meter reach of the Salmon River, Oregon, using an unmanned aerial vehicle (UAV) and rtk-GPS. Structure-from-Motion (SfM) software produced a digital elevation model (DEM) (1.5 cm) and orthophoto (0.37 cm). The photogrammetric approach of applying a site-specific refractive index provided the most accurate (mean error 0.009 m) and precise (standard deviation of error 0.17 m) bathymetric data (R2 = 0.67) over the spectral depth and the 1.34 refractive index approaches. This research provides a quantitative comparison between and within bathymetric mapping methods, and suggests that a site-specific refractive index may be appropriate for similar gravel-bed, relatively shallow, clear streams.

Made available in DSpace on 2014-06-11T19:32:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-03-03Bitstream added on 2014-06-13T20:23:25Z : No. of bitstreams: 1 bufon_agm_dr_rcla.pdf: 6403012 bytes, checksum: c784c56fb01a8bcc3cc685a03f66bd99 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Este trabalho teve como finalidade aplicar análise espacial, visando elaborar um modelo estocástico para determinação do tempo de vida útil de um reservatório de pequeno porte localizado no Centro de Pesquisa e Gestão de Recursos Pesqueiros Continentais (CEPTA/IBAMA)/Pirassununga (SP). Para elaboração do modelo foram utilizados dois métodos: densidade aparente do sedimento utilizando câmaras de sedimentação e batimetria do reservatório. As variáveis estudadas revelaram para o potencial hidrogeniônico (pH) concentrações entre 8,71 e 2,15; oxigênio dissolvido no fundo entre 12,48 e 0,20 mg.L-1; temperatura da água no fundo entre 28,85 e 16,00ºC; transparência da água entre 1,30 e 0,25 m; material em suspensão total entre 618,30 e 2,45 mg.L-1; material em suspensão inorgânico entre 425,80 e 0,20 mg.L-1; material em suspensão orgânico entre 192,60 e 2,15 mg.L-1 e condutividade elétrica da água no fundo entre 40,00 e 5,00 æS.cm-1. Quanto aos resultados da batimetria, verificou-se que houve perda significativa de profundidade durante o ano de 1998. Ao comparar as análises de batimetria e material em suspensão total (MST) verificou-se a perda da profundidade durante os 4 anos estudados de -1,32 m e pela câmara de sedimentação observou-se um ganho de sedimento de 584,05 mg.L-1. Como conclusão obteve-se o valor de 50 anos como o tempo de vida útil da represa. / The purpose of this work is to apply space analysis aiming elaborate a stochastic model for time determination of useful life of a small size reservoir at the Centre of Research and Administration of Continental Fishing Resources (CEPTA/IBAMA)/Pirassununga (SP). For model elaboration were used two methods: apparent density of the sediment using reservoir sedimentation and bathymetry cameras. The studied variables revealed for the pH concentrations between 8,71 and 2,15; oxygen dissolved in the bottom between 12,48 and 0,20 mg.L -1; water temperature in the bottom between 28,85 and 16,00ºC; water transparency between 1,30 and 0,25 m; material in total suspension between 618,30 and 2,45 mg.L-1; material in inorganic suspension between 425,80 and 0,20 mg.L-1; material in organic suspension between 192,60 and 2,15 mg.L-1 and electric conductivity of water in the bottom between 40,00 and 5,00 æS.cm-1. Regarding bathymetry results, it verified that there was significant loss of depth during the year of 1998. When comparing bathymetry and material analyses in total suspension it was verified depth loss during the 4 years studied of -1,32 m and by the sedimentation camera a sediment gain of 584,05 mg.L-1 was observed. As conclusion it obtained the value 50 year as time of useful life for dam.