This research develops a methodology for determining farm scale land managementunits (LMUs) using soil sampling data, high resolution digital multi-spectral imagery (DMSI) and a digital elevation model (DEM). The LMUs are zones within a paddock suitable for precision agriculture which are managed according to their productive capabilities. Soil sampling and analysis are crucial in depicting landscape characteristics, but costly. Data based on DMSI and DEM is available cheaply and at high resolution.The design and implementation of a two-stage methodology using a spatiallyweighted multivariate classification, for delineating LMUs is described. Utilising data on physical and chemical soil properties collected at 250 sampling locations within a 1780ha farm in Western Australia, the methodology initially classifies sampling points into LMUs based on a spatially weighted similarity matrix. The second stage delineates higher resolution LMU boundaries using DMSI and topographic variables derived from a DEM on a 10m grid across the study area. The method groups sample points and pixels with respect to their characteristics and their spatial relationships, thus forming contiguous, homogenous LMUs that can be adopted in precision agricultural applications. The methodology combines readily available and relatively cheap high resolution data sets with soil properties sampled at low resolution. This minimises cost while still forming LMUs at high resolution.The allocation of pixels to LMUs based on their DMSI and topographic variables has been verified. Yield differences between the LMUs have also been analysed. The results indicate the potential of the approach for precision agriculture and the importance of continued research in this area.

Synthetic Vision Systems (SVS) provide an aircraft pilot with a virtual 3-D image of surrounding terrain which is generated from a digital elevation model stored in an onboard database. SVS improves the pilot's situational awareness at night and in inclement weather, thus reducing the chance of accidents such as controlled flight into terrain. A terrain database integrity monitor is needed to verify the accuracy of the displayed image due to potential database and navigational system errors. Previous research has used existing aircraft sensors to compare the real terrain position with the predicted position. We propose an improvement to one of these models by leveraging the stream computing capabilities of commercial graphics hardware. "Brook for GPUs," a system for implementing stream computing applications on programmable graphics processors, is used to execute a streaming ray-casting algorithm that correctly simulates the beam characteristics of a radar altimeter during all phases of flight.

The use of Light Detection and Ranging (LiDAR) information is gaining popularity, however its use has been limited in deciduous forests. This thesis describes two studies using LiDAR data in an Eastern Kentucky deciduous forest. The first study quantifies vertical error of LiDAR derived digital elevation models (DEMs) which describe the forests terrain. The study uses a new method which eliminates Global Positioning System (GPS) error. The study found that slope and slope variability both significantly affect DEM error and should be taken in to account when using LiDAR derived DEMs. The second study uses LiDAR derived forest vegetation and terrain metrics to predict terrestrial Plethodontid salamander abundance across the forest. This study used night time visual encounter surveys coupled with zero-inflation modeling to predict salamander abundance based on environmental covariates. We focused on two salamander species, Plethodon glutinosus and Plethodon kentucki. Our methods produced two different best fit models for the two species. Plethodon glutinosus included vegetation height standard deviation and water flow accumulation covariates, while Plethodon kentucki included only canopy cover as a covariate. These methods are applicable to many different species and can be very useful for focusing management efforts and understanding species distributions across the landscape.

The aim of this study was to map and date glacial flutings with ice flows deviating from the predominating northwesterly ice flow direction in the southern part of Norrbotten County in northern Sweden, and also to investigate if parts of the glacial landscape are older than previously thought. The traditional view is that most landforms in the area were formed during the late Weichselian (W3). Analysis of the new high resolution elevation model (2 m grid) derived from laser scanning was performed after treating the data with a hillshade tool in ArcMap to reveal terrain features such as flutings. The analysis resulted in a map showing four main groups of deviating ice flows (N-S, NO-SV, SO-NV and S-N) and several westerly ice flows. The majority of flutings with deviating ice flows were found in low terrain. This, together with studies suggesting a cold based late Weichselian ice sheet in Norrbotten, implies an old age of the deviating ice flows. The deviating ice flows are interpreted to originate from the first early Weichselian (W1), or predate the onset of the Weichselian glaciation. Some NV-SO flutings were located in high terrain, which implies a younger age relative to the low terrain flutings. They represent the youngest ice flow found in the area, possibly from the second early Weichselian (W2). The new elevation model clearly offers new possibilities for studying small scale landforms and shows that the traditional view of the Weichselian glaciation in northern Swedish needs to be reconsidered.

Thesis (MSc (Geography and Environmental Studies))--University of Stellenbosch, 2007. / Due to the relative scarcity of weather stations, the climate conditions of large areas are not adequately represented by a weather station. This is especially true for regions with complex topographies or low population densities. Various interpolation techniques and software packages are available with which the climate of such areas can be calculated from surrounding weather stations’ data. This study investigates the possibility of using the software package ANUSPLIN to create accurate climate maps for the Western Cape, South Africa. ANUSPLIN makes use of thin plate smoothing splines and a digital elevation model to convert point data into grid format to represent an area’s climatic conditions. This software has been used successfully throughout the world, therefore a large body of literature is available on the topic, highlighting the limitations and successes of this interpolation method. Various factors have an effect on a region’s climate, the most influential being location (distance from the poles or equator), topography (height above sea level), distance from large water bodies, and other topographical factors such as slope and aspect. Until now latitude, longitude and the elevation of a weather station have most often been used as input variables to create climate grids, but the new version of ANUSPLIN (4.3) makes provision for additional variables. This study investigates the possibility of incorporating the effect of the surrounding oceans and topography (slope and aspect) in the interpolation process in order to create climate grids with a resolution of 90m x 90m. This is done for monthly mean daily maximum and minimum temperature and the mean monthly rainfall for the study area for each month of the year. Not many projects where additional variables have been incorporated in the interpolation process using ANUSPLIN are to be found in the literature, thus further investigation into the correct transformation and the units of these variables had to be done before they could be successfully incorporated. It was found that distance to oceans influences a region’s maximum and minimum temperatures, and to a lesser extent rainfall, while aspect and slope has an influence on a region’s rainfall. In order to assess the accuracy of the interpolation process, two methods were employed, namely statistical values produced during the spline function calculations by ANUSPLIN, and the removal of a selected number of stations in order to compare the interpolated values with the actual measured values. The analysis showed that more accurate maps were obtained when additional variables were incorporated into the interpolation process. Once the best transformations and units were identified for the additional variables, climate maps were produced in order to compare them with existing climate grids available for the study area. In general the temperatures were higher than those of the existing grids. For the rainfall grids ANUSPLIN’s produced higher rainfall values throughout the study region compared to the existing grids, except for the Southwestern Cape where the rainfall values were lower on north-facing slopes and high-lying area

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The requirement for quantitative soil information has increased as a consequence of the global scenarios. The digital soil mapping (DSM) seeks to produce consistent data with the current needs through the generation of functional soil maps in multi-scales. The aim of this study was to evaluate the altimetry quality and limitations of digital elevation model (DEM) in order to assist in choosing the most suitable DEM to derive terrain attributes (TA) to develop spatial prediction functions to be applied to digital mapping of soil organic carbon (SOC) of farm scale in the Plateau of the state of Rio Grande do Sul (RS). The study was conducted on a 937 ha area located in the municipality of Giruá, RS, Brazil. They collected 243 sampling points in the 0-5 cm layer and an accomplished planialtimetric survey (PS) considered in this study the truth of the ground of altitude values. DEM evaluated were: DEM-PS (generated from the PS), DEM-LETTER (generated by interpolating the level of topographic map curves), DEM-ASTER, DEM- SRTM and DEM-TOPODATA. The DEM were evaluated for precision altimetry through statistical test value of the square root of the mean square error (RMSE) and application of the Brazilian Cartographic Standard for defining the scale of each DEM based on the accuracy of the altitude. TA derived from each DEM were faced with the AT derived from the DEM-PS. The results showed that the DEM-PS presented the best quality of elevation data (RMSE = 1.93 m), followed by DEM-SRTM (RMSE = 5.95 m), DEM- (RMSE = 8.28 m), DEM-TOPODATA (RMSE = 9.78 m) and DEM-ASTER (RMSE = 15.57 m). The size of the area and gently rolling relief were the main factors that influenced the results. The DEM-PS is suited in scale 1: 10,000 Class D, while DEM-LETTER and DEM-SRTM are suited in scale 1: 50,000 class B, the DEM-TOPODATA the scale 1: 50,000 class D and the DEM-ASTER scale 1: 100,000 Class B. With regard to TA, the DEM-SRTM and DEM-TOPODATA present results closer to the DEM-PS and smaller RMSE values for each TA assessed. The prediction function constructed from the DEM-PS derived from the TA and vegetation index Landasat-7 obtained images explained only 16% of the variance in SOC area. The small spatial resolution of DEM-PS and images associated with the use only of these predictors were the main factors that influenced the results. Based on these results, the DEM-SRTM and DEM-TOPODATA can be used in DSM semi-detailed soil classes. In the case of the SOC DSM suggest the use of these DEM associated with field control points to verify the precision altimetry and the inclusion of variables related to soil management practices. / A demanda por informações quantitativas de solos em nível detalhado de bacias hidrográficas vêm aumentado em decorrência dos cenários globais. O mapeamento digital de solos (MDS) visa gerar dados compatíveis com essas necessidades por meio da geração de mapas funcionais de solos em multi-escalas. O objetivo desse trabalho foi avaliar a qualidade altimétrica e limitações de MDE com a finalidade de auxiliar na escolha do MDE mais adequados para derivar atributos do terreno (AT) para desenvolver funções de predição espacial para serem aplicadas ao mapeamento digital do carbono orgânico do solo em escala de propriedade rural no Planalto do Estado do Rio Grande do Sul (RS). O estudo foi realizado em uma área de 937 ha localizada no município de Giruá, RS, Brasil. Foram coletados 243 pontos amostrais na camada de 0-5 cm e realizado um levantamento planialtimétrico (LP) considerado neste estudo a verdade do terreno dos valores de altitude. Os MDE avaliados foram: MDE-LP (gerado a partir do LP), MDE-CARTA (gerado pela interpolação das curvas de nível da carta topográfica), MDE-ASTER, MDE-SRTM e MDE-TOPODATA. Os MDE foram avaliados quanto à precisão altimétrica por meio de teste estatísticos, valor da raiz quadrada do erro médio quadrático (RMSE) e aplicação da Norma Brasileira de Cartografia para definição da escala de cada MDE com base na precisão da altitude. Os AT derivados de cada MDE foram confrontados com os AT derivados do MDE-LP. Os resultados mostraram que o MDE-LP apresentou a melhor qualidade dos dados de altitude (RMSE = 1,93 m), seguido dos MDE-SRTM (RMSE = 5,95 m), MDE-CARTA (RMSE = 8,28 m), MDE-TOPODATA (RMSE = 9,78 m) e MDE-ASTER (RMSE = 15,57 m). O tamanho da área e relevo suave ondulado foram os principais fatores que influenciaram nos resultados. O MDE-LP se adequou na escala 1:10.000 classe D, enquanto os MDE-CARTA e MDE-SRTM se adequaram na escala 1:50.000 classe B, o MDE-TOPODATA a escala 1:50.000 classe D e o MDE-ASTER escala 1:100.000 classe B. Em relação aos AT, os MDE- SRTM e MDE-TOPODATA apresentam resultados mais próximos do MDE-LP e os menores valores de RMSE para cada AT avaliado. A função de predição construída a partir dos AT derivados do MDE-LP e índice de vegetação obtido de imagens Landasat-7 explicou apenas 16% da variância do COS na área. A resolução espacial pequena do MDE-LP e das imagens associado ao uso apenas dessas variáveis preditoras foram os principais fatores que influenciaram nos resultados. Com base nesses resultados, os MDE- SRTM e MDE-TOPODATA podem ser utilizados no MDS semidetalhado de classes de solos. No caso do MDS do COS sugere-se o uso desses MDE associado com pontos de controle de campo para verificação da precisão altimétrica e a inclusão de variáveis relacionadas a práticas de manejo do solo.

Submitted by JANAINA NATALI ANTONIO null (janaina51@gmail.com) on 2018-02-15T16:54:59Z No. of bitstreams: 2 TESE_JanainaAntonio.pdf: 41977459 bytes, checksum: 3fa0898cf5b3dd50324d815bd11bf520 (MD5) TESE_JanainaAntonio.pdf: 41977459 bytes, checksum: 3fa0898cf5b3dd50324d815bd11bf520 (MD5) / Approved for entry into archive by ALESSANDRA KUBA OSHIRO ASSUNÇÃO (alessandra@fct.unesp.br) on 2018-02-16T11:20:59Z (GMT) No. of bitstreams: 1 antonio_jn_dr_prud.pdf: 41977459 bytes, checksum: 3fa0898cf5b3dd50324d815bd11bf520 (MD5) / Made available in DSpace on 2018-02-16T11:20:59Z (GMT). No. of bitstreams: 1 antonio_jn_dr_prud.pdf: 41977459 bytes, checksum: 3fa0898cf5b3dd50324d815bd11bf520 (MD5) Previous issue date: 2017-11-14 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A expansão de áreas urbanas e os diferentes tipos de uso da terra, nestas áreas, causam modificações nas características naturais dos solos, pois no ambiente urbano há a ação de diversos processos mecânicos, como a retirada, transporte e deposição de materiais de diversas origens e composições. As alterações no solo são significativas, de forma que muitos países inseriram novas categorias de solos aos seus sistemas de classificação. No Brasil, os solos resultantes de ações antrópicas, foram conceituados como Antropossolos, caracterizados pelas alterações na paisagem e na composição física e química, incluindo a presença de artefatos e materiais contaminantes. Para realizar a caracterização e o mapeamento dos Antropossolos, inicialmente foi realizado o levantamento das características dos solos naturais, sua relação com os atributos do relevo no município de Presidente Prudente – SP, e o mapeamento preditivo de solos, com uso de redes neurais artificiais. A compreensão da relação existente entre os solos e os atributos do relevo derivados de um modelo digital de elevação forneceu informações para relacionar os principais padrões de ocorrência de tipos de solos aos atributos de elevação, declividade, curvatura do relevo, geoformas e aspecto. Entre as variáveis utilizadas para o mapeamento preditivo dos solos, as que tiveram destaque foram declividade e geoformas, apresentando similaridade de padrão de ocorrência. As áreas de ocorrência dos Neossolos estão, principalmente, relacionadas às áreas de declividades de 20% ou acima, os Latossolos têm padrão de ocorrência nas áreas com declividades inferiores a 8%, os Argissolos variam em declividades médias acima de 3% e abaixo de 20% e os solos hidromórficos (Gleissolos e Planossolos) estão localizados nos fundos de vale com declividades abaixo dos 3%. As redes neurais artificiais se mostraram uma técnica eficiente para o delineamento das unidades de solos e permitiram a identificação de componentes da paisagem por meio do estabelecimento de padrões gerados a partir das coletas de amostras. Com base nos atributos do relevo e do mapeamento preditivo dos solos foi realizada a caracterização das áreas de antigos depósitos de resíduos sólidos urbanos na área urbana de Presidente Prudente – SP, as quais estão predominantemente localizadas nos compartimentos de fundos de vale, em curvaturas côncavas, declividades de relevo ondulado e forte ondulado e em solos Argilosos e hidromóficos (Gleissolos e Planossolos). Os Antropossolos em antigas áreas de disposição de RSU são classificados no segundo nível como Líxicos, devido à presença de materiais orgânicos e artefatos de origem e composições diversas, e podem conter substâncias contaminantes. Para a classificação no terceiro e quarto níveis foi delimitada uma área de influência a partir de uma das antigas áreas de disposição de RSU, localizada no Parque Furquim. Foram realizadas análises granulométricas e de presença de metais pesados nos solos. Os elementos analisados foram Arsênio (As), Cádmio (Cd), Chumbo (Pb) e Crômio (Cr). Os resultados foram comparados com os Valores de Referência de Qualidade utilizados no estado de São Paulo, e indicaram a presença de Chumbo (Pb) e Crômio (Cr) acima dos Valores de Referência de Qualidade em alguns pontos, localizados à montante da área delimitada, em fundos de vale próximos ao curso d’água. A área foi classificada pela ocorrência de Antropossolos Líxicos Áquicos e Órticos com presença de elementos tóxicos e de Antropossolos potenciais. Por se tratar de um conceito recente, os estudos para o conhecimento das características dos Antropossolos, são fundamentais para a compreensão da sua dinâmica e para propor medidas de recuperação e de planejamento para o uso adequado. / The expansion of urban areas and different types of land use in these areas cause modifications in the natural characteristics of the soils, since in the urban environment there are several mechanical processes, such as the removal, transportation, and deposition of materials of various origins and compositions. The alterations in the soil are significant, with many countries inserting new soil categories into their classification systems. In Brazil, soils resulting from anthropic actions are considered as Anthroposols, characterized by changes in the landscape and physical and chemical composition, including the presence of artifacts and contaminating materials. In order to carry out the characterization and mapping of the Anthroposols, initially a survey of the characteristics of the natural soils was carried out, including their relation with the attributes of the relief in the municipality of Presidente Prudente - SP, and the predictive mapping of soils, using artificial neural networks. Understanding of the relationship between the soils and relief attributes derived from a digital elevation model provided information to relate the main patterns of occurrence of soil types to the attributes of elevation, slope, relief curvature, geoforms, and aspect. Among the variables used for the predictive mapping of soils, those that stood out were slope and geoforms, presenting similarities in patterns of occurrence. The areas of occurrence of the Neosols are mainly related to the slope areas of 20% or above, the Oxisols present a pattern of occurrence in areas with slopes lower than 8%, the Argisols vary in average slopes above 3% and below 20%, and the hydromorphic soils (Gleysols and Planosols) are located in valley bottoms with gradients below 3%. Artificial neural networks proved to be an efficient technique for the delineation of soil units and allowed identification of landscape components by establishing patterns generated from sample collections. Based on the attributes of soil relief and predictive mapping, characterization of areas of former urban solid waste deposits in the urban area of Presidente Prudente – SP was carried out, predominantly located in valley bottom compartments, in concave curves, slopes of undulating relief and strong undulation and in clayey and hydromorphic soils (Gleysols and Planosols). Anthroposols in former USW disposal areas are classified in the second level as Líxicos, due to the presence of organic materials and artifacts of various origins and compositions, which may contain contaminating substances. For classification in the third and fourth levels, an area of impact from one of the former USW disposal areas was delimited, located in Parque Furquim. Granulometric analyzes and evaluation of the presence of heavy metals in the soils were carried out. The analyzed elements were Arsenic (As), Cadmium (Cd), Lead (Pb), and Chromium (Cr). The results were compared with the Quality Reference Values used in the state of São Paulo and indicated the presence of Lead (Pb) and Chromium (Cr) above the Quality Reference Values at some points, located upstream of the delimited area, in valley bottoms near the watercourse. The area was classified by the occurrence of Líxicos Áquicos and Órticos Anthroposols with the presence of toxic elements and potential Anthroposols. As it is a recent concept, studies aiming to increase knowledge on the characteristics of Anthroposols are fundamental to the understanding of their dynamics and to propose measures of recovery and planning for appropriate use. / 2013/03505-6

Resumo: Desde o advento dos primeiros satélites de Sensoriamento Remoto, vários são os estudos desenvolvidos com o intuito de utilizar as imagens produzidas por estes sensores para fins cartográficos. Apesar das imagens de baixa e média resolução não possuírem a precisão requerida para aplicações cartográficas em escalas grandes, existem vantagens como: serem imagens multiespectrais, possuírem periodicidade e menores custos para a sua aquisição, quando comparadas com as obtidas através dos tradicionais levantamentos aerofotogramétricos. Uma melhoria presente nos satélites de alta e média resolução é a capacidade de visada off nadir, o que permite à formação de pares estereoscópicos e a reconstrução 3D da cena imageada, a geração de modelos digitais de elevação (MDE) e a produção de imagens ortorretificadas, dentre outros produtos. Com os primeiros pares estereoscópicos adquiridos pelo sensor HR-CCD (High Resolution Charge-Coupled Devices) do CBERS-2 (2004), surgiu a possibilidade de realizar estudos objetivando a geração de produtos cartográficos a partir desses estereopares... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Since the advent of the first Remote Sensing satellites, many studies have been developed with the intention of using the images produced by these sensors for cartographic purpose. Although these images of the average resolution do not possess the accuracy required for cartographic applications in big scales, their advantages include being multispectral, periodic repetition of acquisition, and lower cost when compared to images obtained through traditional aerial photogrammetric surveys. An improvement present in medium and high resolution satellites is their off nadir capacity, which allows 3D reconstruction based on stereoscopy, the generation of digital elevation models (DEM) and the production of orthorectified images, among others products. With the first stereoscopic pairs acquired by the CBERS-2 (2004) HR-CCD (High Resolution Charge-Coupled Device) sensor, the possibility now exists of realizing studies whose goal is generating cartographic products from these stereo pairs. Within this context, this work evaluated the geometric quality of a CBERS-2 HR-CCD stereo pair making use of the DLT (Direct Linear Transformation) mathematical model and Polynomial-Based Pushbroom model, available from the Leica Photogrammetry Suite (LPS) digital photogrammetry system by Leica Geosystems, classifying them in accordance with the Cartographic Accuracy Standards... (Complete abstract click electronic access below) / Orientador: Júlio Kiyoshi Hasegawa / Coorientador: Maurício Galo / Banca: João Fernando Custódio da Silva / Banca: Hideo Araki / Mestre

Submitted by Aline Batista (alinehb.ufpel@gmail.com) on 2018-06-18T19:24:16Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Maira_Moura.pdf: 30957776 bytes, checksum: e0ff4cced3cbe165233684b6434e4ce9 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-06-18T19:47:11Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Maira_Moura.pdf: 30957776 bytes, checksum: e0ff4cced3cbe165233684b6434e4ce9 (MD5) / Made available in DSpace on 2018-06-18T19:47:18Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Maira_Moura.pdf: 30957776 bytes, checksum: e0ff4cced3cbe165233684b6434e4ce9 (MD5) Previous issue date: 2018-03-01 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / A água é um recurso natural indispensável à vida e primordial ao desenvolvimento econômico de uma região. Devido às mudanças climáticas, associadas às ações antrópicas e ao crescimento populacional, a ocorrência de problemas relacionados a cheias em bacias hidrográficas tem aumentado. O estudo de cheias em bacias hidrográficas permite a quantificação da magnitude das vazões de pico e do hidrograma de escoamento superficial direto oriundos de um ou mais eventos de chuva. No entanto, tais estimativas dependem de dados de séries históricas, o que pode ser problemático nos países em desenvolvimento devido a existência de um número insuficiente de seções com monitoramento fluviométrico, tornando a modelagem hidrológica de cheias uma ferramenta imprescindível. Diferentes métodos para estimativa de cheias vêm sendo apresentadas e utilizadas na literatura, com destaque para a do Hidrograma Unitário (HU), a do Hidrograma Unitário Instantâneo (HUI) e a do Hidrograma Unitário Instantâneo Geomorfológico (HUIG). Um modelo de HUI amplamente utilizados é o de Nash (HUIN), para o qual diversas propostas geomorfológicas vêm sendo desenvolvidas, estabelecendo relações para seus parâmetros a partir da caracterização física da bacia hidrográfica e da rede de drenagem. Durante a caracterização de bacias hidrográficas em softwares de geoprocessamento, a principal informação é a do relevo, obtida a partir de um Modelo Digital de Elevação (MDE), que pode ser obtido a partir de cartas topográficas, ou de imagens de radar (ex. SRTM) e sensor (ex. ASTER). O principal objetivo deste estudo foi avaliar a aplicabilidade e confiabilidade de diferentes fontes e escalas de informação do relevo visando à modelagem de cheias através do modelo de HUIN fundamentado em parâmetros geomorfológicos, tomando como base cinco bacias hidrográficas experimentais de diferentes características fisiográficas e dotadas de monitoramento hidrológico. Os MDEs utilizados foram obtidos de cartas topográficas na escala 1:50.000, de imagens SRTM com 30m e 90m, de imagens do banco de dados TOPODATA, de imagens ASTER, e somente para a menor bacia, de dados de um levantamento planialtimétrico. Foram selecionadas quatro propostas geomorfológicas para o HUIN, sendo duas delas baseadas na teoria do HUIG, e as outras duas em estudos empíricos realizados em diferentes bacias hidrográficas. Com base nos resultados obtidos para as bacias analisadas, as principais conclusões deste estudo foram: a) os parâmetros mais impactados pela fonte e escala da informação do relevo são a declividade do curso d’água principal e as razões de Horton e de Schumm; b) as bacias planas são mais suscetíveis a erros altimétricos e estes aumentam conforme a área da bacia diminui; c) não é possível observar uma combinação de proposta-MDE que descreva melhor ou pior o conjunto de bacias analisadas, nem levando em consideração a declividade, nem o tamanho da área das bacias; d) as propostas geomorfológicas que não dependem de informação da velocidade do escoamento apresentaram bons resultados em relação as baseadas na teoria do HUIG; e) a combinação de diferentes propostas permite estimar de forma satisfatória o comportamento do hidrograma de escoamento superficial direto e o tempo e a vazão de pico nas bacias estudadas. / Water is a natural resource indispensible to life and essential to regional economic development. Due to climate change, anthropic interferences, and rapid population growth, the occurrence of flood-related natural hazards in watersheds has increased. Watershed flood-related studies allow the estimation of peak streamflow and direct surface runoff hydrograph resulting from single or multiple rainfall events. However, such estimations are directly dependent on existing streamflow historical series, which might be troublesome in developing countries due to the lack of streamflow gauging stations. In this context, indirect flood estimation methods stand out. Among the different flood estimation methods presented in the literature, the Unit Hydrograph (UH), Instantaneous Unit Hydrograph (IUH), and Geomorphological Instantaneous Unit Hydrograph (GIUH) have caught researchers’ attention. The Nash’s IUH (NIUH) is one of the most widely used IUH models. Several geomorphological approaches have been developed for NIUH, thus relating its parameters to watershed and drainage network physical characteristics. During the characterization of watersheds in geoprocessing softwares, the main information is that of relief obtained from a Digital Elevation Model (MDE) which can be obtained from topographic maps or from radar images (e.g. SRTM) and sensor images (e.g. ASTER). The main objective of this study was to evaluate the applicability and reliability of different relief data sources and scales for determination of geomorphological parameters required to estimate floods from NIUH. This study took into account data sets from five experimental watersheds with different physiographical characteristics, which have hydrological monitoring. The DEMs analysed in this study were obtained from topographical maps in the 1:50,000 scale, SRTM images with 30 and 90-meter spatial resolution, TOPODATA database, ASTER images. For the smallest watershed, an in situ topographic survey was also carried out for DEM derivation. Four geomorphological approaches for the NIUH were selected; two of them were based on the GIUH theory, whereas, the others were adjusted from empirical studies conducted in different watersheds. Based on the results obtained for the analysed watersheds, the main conclusions were: a) the main watercourse’s slope and Horton’s and Schumm’s ratios are the most sensitive parameters to relief data sources and scales; b) flat watersheds are the most susceptible to altimetry errors, which increase as the watershed area decreases; c) it is not possible to identify any combinations of geomorphological approach-DEM that better or worse describe all the analyzed watersheds when assessing watershed slope or drainage area independently; d) the geomorphological approaches which do not depend on streamflow speed information presented satisfactory results when compared to those based on GIUH theory; and e) the combination of different approaches enables to satisfactorily estimate the behavior of direct surface runoff hydrographs and their peak streamflow and time in all the considered watersheds.

O uso de geotecnologias pode contribuir de forma muito significativa para os estudos em geomorfologia. Considerando os principais componentes desta ciência, morfografia, morfometria, morfogênese e morfocronologia, os modelos digitais para a representação da superfície da Terra podem ser amplamente utilizados na aquisição de muitas destas informações. O uso de Modelos Digitais de Elevação (MDE) há alguns anos, já é uma realidade em estudos envolvendo geomorfologia. A sua utilização permite a aquisição de variáveis e parâmetros objetivos que podem servir à definição de critérios para o agrupamento de unidades geomorfológicas. Podendo, portanto, ser um instrumento valioso para mapeamento de áreas amplas em escalas de 1:50.000 e 1:100.000. Para tanto, é necessário definir os critérios coerentes e os algoritmos de segmentação que oferecem os melhores resultados para as diversas áreas de estudo. Os MDE gerados pela missão Shuttle Radar Topography Mission (SRTM) são de vasta abrangência e contemplam todo o território nacional brasileiro. Portanto, os dados gerados pela missão podem ser uma importante fonte de informação para mapeamentos com metodologia única. O alcance deste objetivo não garante avanços metodológicos na cartografia geomorfológica, tendo em vista que a possibilidade de comparação entre diferentes cartas geomorfológicas de detalhe ainda é restrita. / Geotechnologies can contribute significantly to geomorphology studies. Whereas the main principles of this science, mophography, morphometry, morphogenesis and morphochronology, the digital models used to represent the Earth surface can be widely utilized in a bunch of these data. Lately, the use of Digital Elevation Model (DEM) can be considered a reality in geomorphology studies. The utilization allows the acquisition of objective variables and parameters that can be suitable for definition of geomorphological units. Hence, can be a valuable tool for wide area mapping using 1:50.000 and 1:100.000 scales. For that reason, it is necessary to define coherent criteria and the proper segmentation algorithm in order to reach better results for different study cases. DEM provided by Shuttle Radar Topography Mission (SRTM) are wide range and cover the whole national territory. Therefore, data provided by this mission can be an important information for a single methodology mapping project.