yes / Urban flooding is a combined product of the climate and watershed geomorphology. River system is one of the vital components of watershed geomorphology. The geomorphic characteristics of rivers have important effect on the formation of flooding. However, there have been few attempts so far to investigate the relationship between flooding frequency, the probability of flooding, and the geomorphological complexity of river system. Such relationship is essential in order to predict likely responses of flooding frequency to the large-scale changes in the complexity of the river networks induced by accelerating urbanization around river. In this study we investigate the correlation between geomorphological characteristics of river system and the probability of flooding. Hangzhou city in China, which has suffered severe flooding, is chosen as a case study to evaluate this correlation and to investigate the impact of changes of drainage networks morphology on the local flooding. The fractal dimension, which is used to quantitatively assess geomorphological complexity of river network, is calculated by using box-counting method based on fractal geometry for eight sub river networks in Hangzhou. A model based on the correlation of flooding frequency and fractal dimension is established. The model is applied to investigate the effect of the rapid urbanization induced changes of river geomorphology on the local flood frequency in two typical regions in Hangzhou. The results show that the flood frequency/events increases with the decrease of fractal dimension of the river network, indicating that the geomorphologic complexity of river network has an important effect on flooding. This research has great referential value for future flood quantitative investigation and provides new method for urban flood control and river system protection. / Key Scientific and Technical Project of Water Conservancy of Zhejiang Province (Grant No: RB1401)

A combination of geological and hydraulic techniques represents the most sensible approach to flood hazard analysis on alluvial fans. Hydraulic models efficiently yield predictions of flood depths and velocities, but the assumptions on which the models are based do not lead to accurate portrayals of natural fan processes. Geomorphological mapping, facies, mapping, and hydraulic reconstructions of past floods provide data on the location, types, and magnitude of flood hazards, respectively. Geological reconstructions of past floods should be compared with the results of hydraulic modeling before, potentially unsound, floodplain management decisions are implemented. The controversial Federal Emergency Management Agency procedure for delineating flood-hazard zones underestimated the extent, velocity, and depth of flow during recent floods on two alluvial fans by over 100, 25, and 70 percent, respectively. Flow on the alluvial fans occurs in one or more discontinuous ephemeral stream systems characterized by alternating sheetflood zones and channelized reaches. The importance of sheetflooding is greater on fans closer to the mountain front and with unstable channel banks. Channel diversions on five alluvial fans repeatedly occurred along low channel banks and bends where the greatest amount of overland flow is generated. Channel migration occurs through stream capture whereby overland flow from the main channel accelerates and directs erosion of adjacent secondary channels. The recurrence interval of major channel shifts is greater than 100 years, but minor changes occurred on all five fans during this century. Small aggrading flows are important, because they decrease bank heights and alter the location of greatest overland flow during subsequent floods. The results of this study demonstrate that (1) geological reconstructions of past floods can check the results of hydraulic models, (2) the character of flooding on alluvial fans can vary significantly in the same tectonic and climatic setting due to differences in drainage-basin characteristics, and (3) flood-hazard assessments on alluvial fans must be updated after each flood, because the location and timing of channel diversions can be affected by small floods.

MENVSC (Geography) / Department of Geography and Geo - Information Sciences / Detailed geomorphological mapping is important for monitoring environmental phenomena, it is therefore crucial that the methods employed for mapping are accurate. The basis of remote sensing for geomorphological work is moving from the consideration of whether satellite data are accurate for landform mapping to how surfaces of interest can be defined from remote sensing data, since earlier approaches of mapping are deemed costly and tedious. The aim of this study is to assess the suitability of ASTER and SRTM DEMs, and satellite imagery in detailed geomorphological mapping. Field survey and aerial photo interpretation were used to prepare a reference geomorphological map for comparisons. A similar approach of demarcating landform boundaries from aerial photographs was implemented to segment the DEMs into landform classes. The software packages that were used for processing the satellite data to create detailed geomorphological maps are QGIS with GRASS and SAGA plugins, and ENVI. The resultant geomorphological units’ maps from the DEMs when compared with the reference geomorphological map, show that the automated classification technique has advantages in terms of its efficiency and reproducibility. Nevertheless, distinct limitations of the technique are apparent and the technique is not suitable for detailed geomorphological mapping in the proposed study area. / NRF

David, D. (2010): Geomorphological analysis and development relief of central part in Troskovická vrchovina (Highland) (Bohemian Paradise). Charles University in Prague, Faculty of Sience, Department of Physical Geography and Geoecology. The central part of Troskovická vrchovina Highland lies between towns Turnov and Jičín in Jičínská pahorkatina (Hilly land) in Geopark Bohemian Paradise. It is a rugged rocky area mostly built of sedimetary rocks (Cretaceous quartz sandstones). The relief is cut by canyons and in the center of plateau is vulcanic neck Trosky. This book contains results of detailed geomorphological mapping and analysing of the area. The major product of this study is detailed geomorphological map 1:10 000. Key words: Bohemian Paradise, detailed geomorphological mapping, geomorphological analysis, Střeleč pit (main), sandstone relief, vulcanic rocks and Trosky neck.

This research has been focused on the characterisation and analysis of the deposits of large-scale mass movement events that shaped the North Sea Fan since the Mid-Pleistocene. Located at the mouth of the cross-shelf trough Norwegian Channel, the North Sea Fan is one of the largest through-mouth fans in the glaciated european margin with an area of approximately 142,000 km2. Submarine mass movement processed have occurred intermittenrly throughout the Quarternary history of the North Sea Fan, related to recurrent climate-related episodes of growth and retreat of the ice sheets. These processes can transport large amounts of sediment from the upper shelf up to the abyssal basins, playing an important role on the evolution of continental margins and can also reporesnet major geological hazards. This thesis uses mainly 3D seismic data to investigate the external geometry and internal structure of large-scale mass movement deposits. The high spatial resolution provided by the 3D seismic data has allowed a detailed geomorpholocial analysis of these deposits, This study involved the interpretation of the seismic data and the detailed pickling of key reflectors followed by tge extraction of both horizon and window-based seismic attributes. Digital elevation models of the key reflectors and their seismic attribute maps were then transferred to a geographical information system (GIS) where they were interactively interpreted using spatial analysis tools and the full visualisation potential of the software. The outcomes of this study highlight the importance of detailed horizon pickling and interactice interpretation followed by spatial analysis and visualisation in GIS environment. The identification of acoustic patterns within deposits that are normally described from 2D seismic as chaotic or acoustically transparent emphasizes the potential of detailed analysis of 3D seismic data. It gives an example of how this type of data can provide new insights into the mechanisms and processes associated with mass movements. In particular, amplitude and RMS amplitude maps provide remarkable detailed information of internal deformation structures whereas slope, shaded-relief and thickness maps allowed detailed characterisation of the external geometry. Various types of kinematic indicators can be recognized within the mass movement deposits through combined seismic analysis and detaield morphological mapping.

The aim of this master thesis is to create an application to generate smooth contours with the method of non-linear, so-called geomorphological interpolation over triangulated irregular network using patch technique. The introductory part consists of the state of art in the field of patch modelling and description of georelief in the form of digital terrain models. The core of the work comprises the mathematical background of Bézier triangle patches using barycentric coordinates and interpolation techniques with definition of continuity. The main contribution is a proper algorithm of balanced patch smoothing in order to generate smooth contours as form of georelief representation. Description of linear contour interpolation over triangulated irregular network as a method of indirect geomorphological interpolation is also part of the core. Finally, the last part describes the implementation of algorithms that forms the application, presents and evaluates the results on synthetic and real data.

Este estudo apresenta conhecimento geomorfológico sobre sistemas físicos meândricos e, em especial, busca o entendimento das atividades antrópicas sobre estes sistemas físicos, exemplificando assim um dos princípios fundamentais da Antropogeomorfologia ou Geomorfologia Antropogênica. A pesquisa tem como objetivo a análise qualitativa e quantitativa das mudanças produzidas pelas atividades de mineração de areia em um compartimento fluvial da planície meândrica do Rio Embu-Guaçu, setor sul do município de São Paulo (SP). O estudo das mudanças foi realizado com utilização da cartografia geomorfológica evolutiva como recurso analítico das condições do sistema físico em situação préintervenção e após 22 anos de extração de areia (situação durante intervenção). Para tanto, foram produzidos dois mapas geomorfológicos de detalhe da área de estudo: um, referente ao ano de 1981, e representa a morfologia original, o outro, referente à 2003, representa a morfologia antropogênica. A seleção e representação das formas, materiais e processos que constituem os mapas geomorfológicos, bem como sua análise comparativa baseiam-se em um conjunto de geoindicadores considerados como parâmetros para interpretação qualitativa e quantitativa. / This study presents the geomorphological knowledge about physical meandering systems and pursuits the understanding of the anthropic activities effects on these physical systems, so characterizing one of the main principles of a anthropogeomorphology and anthropogenic geomorphology. The main purpose of this research was the qualitative and quantitative analysis of the modifications performed by sand mining activities in a fluvial compartment of the meandering floodplain of the Embu-Guaçu river, in the southern sectin Sao Paulo county. This study was performed with the application of evolutionary geomorphological cartography mapping as analytical tool for the physical system conditions in a preintervention situation and after 22 year of sand extraction (state during intervention). Two detailed geomorphological maps were produced: one refers to 1981 and presents the original morphology and the other to 2003 including the anthropogenic morphology. The selection and representation of forms, materials and processes included in geomorphological maps as well as the comparative analysis were based upon a series of geoindicators considered as qualitative and quantitative interpretation parameters.

No presente trabalho analisam-se os aspectos geomorfológicos de três setores da bacia hidrográfica do rio Cotia, localizada a oeste da Região Metropolitana de São Paulo. Foram elaborados mapas com esboço geomorfológicos de cada setor a partir de base cartográfica na escala 1:25.000, imagens de satélite e fotografias aéreas. A análise das fotografias áreas e imagens de satélite, juntamente com a revisão bibliográfica da área de estudo, permitem a identificação e caracterização das feições geomorfológicas, bem como a sua dinâmica no intervalo de 40 anos (1962-2002). A planície fluvial é entendida como um sistema que reflete as mudanças ocorridas na bacia hidrográfica. As feições geomorfológicas estão localizadas na planície de inundação. Considera-se a planície fluvial como leito regular (leito maior). Essa delimitação estabelece o critério para aplicação de Área de preservação Permanente (APP). Os setores (A,B e C) estudados apresentam características geomorfológicas semelhantes. A expansão urbana sobre a planície fluvial dos setores é crescente. Faz-se necessário o estabelecimento de áreas de proteção na planície. A dinâmica fluvial estabelece os limites de expansão da urbanização. / This paper analyses the geomorphological features from three sectors in the Cotia Rivers basin, located in the western part of the metropolitan area of Sao Paulo. Some Maps have even been drawn starting from a cartographic base on the scale of 1:25.000, satellite images and aerial photographs. The scan of the aerial photographs andsatellite images, with a bibliographic review in this study area, allow the identification and characterization of the geomorphological features, as well as their dynamic during 40 years (1962 2002). The fluvial plain is understood how a system that reflects the changes occurring in the basin. The geomorphological features are located at the flood plain. The fluvial plain is considered like a regular riverbed (flood prone width). This delimitation provides criteria to the application of a Permanent Preservation Area (APP). The sectors (A, B and C) were studied contains similar geomorphological characteristics. The urban sprawl on the fluvial plain in the sectors is increase. It is necessary the establishment of protection areas at the plain. The fluvial dynamic establishes the urban sprawl limits.

Afim de se avaliar a dinâmica geomorfológica e social do município de Ubatuba, litoral norte do Estado de São Paulo, a pesquisa procurou levantar dados multidisciplinares das questões envolvidas, para a partir de então elaborar um banco de dados georreferenciados. A análise conjunta dos tipos de rocha, tipos de formas de relevo, dos graus de declividade, da concentração de aspectos morfotectônicos e o tipo de ocupação e concentração das distribuições urbanas do município culminou em um mapa de Risco Potencial de Acidentes Naturais. Os aspectos apresentados, quanto à avaliação de lineamentos, avaliação atualizada da distribuição censitária da região, e a inter-relação dos dados físicos e sociais, constituem aprofundamento do arcabouço fundamental para o pleno e racional desenvolvimento do município e região. Procurando estabelecer diálogo entre os dados concluídos e a sociedade que sofre com os riscos avaliados em Ubatuba, a pesquisa buscou que as avaliações sobre o material cartográfico final fossem discutidas por setores, divididos pelas sub-bacias que compõem o município. Desta forma, a apresentação dos dados obtidos apresenta um aspecto importante de individualização das questões particulares de cada bairro e cada área afetada, ou não, pelas diversas classes de risco avaliadas no mapa concluído / In order to assess the geomorphological and social dynamics of Ubatuba, northern coast of São Paulo, the research sought to raise multidisciplinary data of the issues involved, to thereafter prepare a georeferenced database. The municipality joint analysis of rock types, types of landforms, the degrees of slope, the concentration of morphotectonic aspects, occupancy type and concentration of urban distributions culminated in a Map of Potential Hazard of Natural Accidents. The aspects, regarding the evaluation guidelines, updated review of census region distribution, and the interrelationship of physical and social data, are deepening the fundamental framework for the full and rational development of the municipality and region. Seeking to establish dialogue between the concluded data and society that suffers from the assessed risks in Ubatuba, the research sought that evaluations on the final cartographic material were discussed by sectors, divided by sub-basins that make up the municipality. Thus, the presentation of data presents an important aspect of differentiating the particular issues of each neighborhood and each affected area, or not, for various categories evaluated in the final map

Os empreendimentos hidrelétricos são sistemas de engenharia empregados para extrair energia dos sistemas naturais e por isso, são alteradores de paisagem por excelência. Para compreender o histórico de derivações da paisagem, faz-se mister compreender o histórico de intervenções sobre os sistemas físicos (vales, encostas, rios lagos). Pela dimensão dos impactos causados por empreendimentos hidrelétricos nos sistemas físicos é que se define o objetivo principal da pesquisa que foi realizar uma leitura da História da Paisagem na área diretamente afetada pelas PCH Rio do Peixe I e II (área de estudo). A sub-bacia do rio do Peixe abrange o reservatório e as estruturas civis das usinas mencionadas, localizadas nos municípios de São José do Rio Pardo e Divinolândia, estado de São Paulo), tendo como pano de fundo conceitos e teorias Biogeográficas e da Geomorfologia Antropogênica). Realizou-se uma revisão bibliográfica ressaltando-se os conceitos de mudança e impacto por meio da abordagem Antropogeomorfológica, sendo possível compreender, assim, o processo de derivação da paisagem analisada, enaltecendo-se os impactos e mudanças de natureza geomorfológica típicas da intervenção do setor elétrico na paisagem. Para tal, foi feita uma sistematização de geoindicadores referentes às morfologias original semipreservada e antropogênica, de modo a promover uma avaliação de impactos em empreendimentos hidrelétricos. Na sequência, definiram-se, a partir dos geoindicadores nas condições de morfologia original semi-preservada e antropogênica, os conteúdos das legendas dos mapas correlatos, de modo a se elaborar uma cartografia geomorfológica de detalhe em ambas as condições. A partir dos mapeamentos mencionados, foi possível quantificar e comparar os impactos atribuídos à implantação das PCH Rio do Peixe I e II, demonstrando, assim, a magnitude das transformações na paisagem dos empreendimentos em estudo. Por fim, promoveu-se uma comparação dos mapeamentos geomorfológicos de detalhe realizados com a metodologia de Avaliação Ambiental Integrada de empreendimentos hidrelétricos, utilizada pelo Sistema Eletrobrás em estudos de viabilidade ambiental de obras relacionadas ao setor elétrico. Nesta metodologia são definidos índices e indicadores para avaliação do grau de sensibilidade, impactos e fragilidades ambientais decorrentes da implantação de empreendimentos hidrelétricos. De modo geral, os resultados contribuíram para o conhecimento dos impactos relacionados ao meio físico na paisagem diretamente afetadas pelas PCH Rio do Peixe I e II, resultando em indicações para um maior aprimoramento nas propostas metodológicas utilizadas na avaliação de viabilidade ambiental de empreendimentos hidrelétricos. / Hydroelectric Power Plants are engeneering systems to extract energy of natural systems and for that reason they highly modify the landscape. In order to understand the history of lansdcape derivations is it necessary understand the history of interventions upon physical systems (river valleys, slopes, rivers and lakes.) Considering the dimensions of impacts caused to hydroelectric ventures in physical systems, this research intends to perform a reading of the Hystorical Geography of Landscape in the direct affected area of Rio do Peixe I and II Small Power Plants (study area). The Rio do Peixe sub-basin wich includes reservoir and civil infrastructure of mentioned hydroelectric power plants, located in São José do Rio Pardo and Divinolândia municipalities, São Paulo State), having as background biogeographicals and of Anthropogenic Geomorphology concepts and theories. An extensive review of literature highlighting the concepts of environment changes and impacts through Anthropogeomorphology approach is made, leading to understand the process of derivation of the landscape analysed, exalting too, the impacts and environmental changes of geomorphological nature, typical of the intervention of electrical sector in the landscape.To achieve this goal, a systematization of geoindicators referring to semipreserved and anthropogenic morphologies is made, in order to promove an environmental impact assessment in hydroelectric ventures. On the way of research the content of legends of the maps is defined related to a list of geoindicators concerning the semi-preserved and anthropogenic morphologies conditions. This had led elaboration of a detailed geomorphological cartography under both conditions. From the mentioned maps it was possible quantifying and mapping the impacts assigned to the implantation of Rio do Peixe I and II Small Power Plants, demonstrating the magnitude of the landscape transformations of the ventures in study. Finally, a comparision among detailed geomorphological maps and the maps produced using the methodology of Integrated Environmental Assessment of Hydroelectric Ventures (applied by Eletrobras System in studies of environmental feasibility of ventures concerned to the electric sector) is made. In this methodology rates and indicators are defined to evaluate the environmental sensibilities, fragilities and impacts arising from the implantation of hydroelectric ventures. In general, the results of the research allows the identification of the impacts concerning the physical environment in the directly affected landscape by Rio do Peixe I and II Small Power Plants, providing contributions to deeper the methodological proposals used in studies of environmental feasibility of hydroelectrical ventures.