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This article presents the results of mapping the flow routes of surface runoff in an area characterized by profound changes in relief caused by anthropic interventions. We chose the Tucum stream upper basin (Sao Pedro, São Paulo - Brazil) as a case study because it is marked by the advance of urbanization on land with strong susceptibility to erosion, with the presence of linear erosive features (ravines and gullies) and a complex history of interventions seeking to control them. We obtained primary data from a topographic survey in the field and carried out operations to develop a Hydrologically Consistent Digital Elevation Model (HCDEM) in the ArcGIS 10.1 program. Then, the Concentrated Flow Map of the area was elaborated from the modeling using the Multiple Flow algorithm in the ArcView 3.2 program. The results showed that topographic features of detail, especially technogenic terraces, have exercised marked control over the flow routes of surface runoff, contributing to generating erosive advance vectors of the ravines and gullies. Resumo Este artigo apresenta os resultados do mapeamento das rotas de fluxo do escoamento superficial em área caracterizada por intensas modificações do relevo causadas por intervenções antrópicas. Como estudo de caso foi escolhida a alta bacia do córrego Tucum (São Pedro - SP), por apresentar um cenário marcado pelo avanço da urbanização sobre terrenos com forte suscetibilidade à erosão, com a presença de feições erosivas lineares (ravinas e voçorocas), e um complexo histórico de intervenções buscando o controle de tais processos. Foram utilizados dados primários, obtidos a partir de levantamento topográfico em campo, e executadas operações visando à elaboração de um Modelo Digital de Elevação Hidrologicamente Consistente (MDEHC), no programa ArcGIS 10.1. Em seguida, foi elaborada a Carta de Fluxo Concentrado da área, a partir da modelagem através do algoritmo Multiple Flow, no programa ArcView 3.2. Os resultados permitiram constatar que feições topográficas de detalhe, em especial, terraços tecnogênicos, têm exercido controle marcante sobre as rotas de fluxo do escoamento superficial, contribuindo para a geração de vetores de avanço erosivo das ravinas e voçorocas existentes na área.

Different studies of geomorphological science are dedicated to understanding the effect of human action on the natural dynamics of environments. Following it, this article aims to identify the effect of agriculture and conservation techniques on the dynamics of slope and bottoms of valley processes in a degraded rural area. We selected, for it, the sub-basins of Areia Dourada stream, located in the city of Marabá Paulista (SP), as objects of study, in which we used the principles of retrospective mapping, with the mapping of land use and superficial surface cover and the geomorphological features of 1963, 1979, 1997, 2011 and 2016. For the analysis, along with the mappings and field records, we used the Pearson’s Correlation Coefficient (p), together with quantified data, to evaluate the changes of the forms of relief from land use in the five mapped years. As a result, we verified: joint development of the erosive processes in different topographic compartments; feedback system between slope and bottoms of valley processes; the low efficiency of the agricultural terraces, both in the cultivated areas, but especially in the pasture areas, in order to contribute to the erosive dynamics by feeding erosive subsurface processes, while not containing the surface ones. Resumo Distintos estudos da ciência geomorfológica se dedicam a compreender o efeito da ação humana na dinâmica natural dos ambientes. Nessa perspectiva, o presente artigo objetiva identificar o efeito da agricultura e das técnicas conservacionistas sobre a dinâmica dos processos de vertentes e de fundos de vale em uma área rural degradada. Para tanto, como objeto de estudo foram selecionadas subbacias do ribeirão Areia Dourada, localizadas no município de Marabá Paulista (SP), nas quais se utilizaram de princípios da cartografia retrospectiva, com o mapeamento do uso e cobertura superficial da terra e das feições geomorfológicas nos anos de 1963, 1979, 1997, 2011 e 2016. Para análise, junto aos mapeamentos e registros de campo, buscou-se com o Coeficiente de Correlação de Pearson (p) avaliar conjuntamente, com dados quantificados, as alterações das formas de relevo a partir do uso da terra nos cinco anos mapeados. Como resultado, constatou-se: desenvolvimento conjunto dos processos erosivos em distintos compartimentos topográficos; sistema de retroalimentação entre os processos de vertentes e fundos de vale; a baixa eficiência dos terraços agrícolas, tanto nas áreas de cultivo, mas, sobretudo nas áreas de pasto, de modo a contribuírem com a dinâmica erosiva ao alimentar processos erosivos de subsuperfície, ao mesmo tempo que não contém os de superfície.

This work aimed to evaluate the relief features of the Taturi River watershed Paraná state, Brazil, seeking to identify the interrelationship between the lithologies, the linear features linked to fractures and faults, erosive features and types of landforms. For that, the geomorphological mapping of the area and the survey of morphostructural data were cattied out, through the elaboration of the drainage density, dissection depth, slope and lineation maps. The analysis of these maps made it possible to identify different sectors, mostly determined by the lithological variation and by the lineaments. In this way, the hydrographic basin of the Taturi River, despite its low slope morphology, has morphological and, therefore, varied procedural characteristics, wich are linked to lithology and lineaments. Thus, the domain sectors of sandy lithologies present morphologies that indicate greater intensity of erosive processes, which must be considered when using and occupying the land. Este trabajo tuvo como objetivo evaluar los rasgos de relieve de la cuenca del Río Taturi estado de Paraná, Brasil, buscando identificar la interrelación entre las litologías, los rasgos lineales vinculados a fracturas y fallas, los rasgos erosivos y los tipos de accidentes geográficos. Para ello, se realizó el mapeo geomorfológico del área y el levantamiento de datos morfoestructurales, mediante la elaboración de los diagramas de densidad de drenaje, profundidad de disección, pendiente ylineamiento. El análisis de estas letras permitió identificar diferentes sectores, en su mayoría determinados por la variación litológica y por los lineamientos. De esta forma, la cuenca hidrográfica del Río Taturi, a pesar de su morfología de baja pendiente, presenta características morfológicas y, por tanto, procedimentales variadas que están ligadas a la litología y los lineamentos. Así, los sectores de dominio de las litologías arenosas presentan morfologías que indican mayor intensidad de procesos erosivos, los cuales deben ser considerados a la hora de utilizar y ocupar el terreno. Este trabalho teve como objetivo avaliar as feições do relevo da bacia do Rio Taturi (PR), buscando identificar a inter-relação entre as litologias, as feições lineares vinculadas a fraturas e falhas, as feições erosivas e os tipos de forma de relevo. Para isso, foi realizado o mapeamento geomorfológico da área e o levantamento de dados morfoestruturais, por meio da elaboração das cartas de densidade de drenagem, profundidade de dissecação, clinográfica e lineamentos. A análise dessas cartas possibilitou identificar diferentes setores, determinados em sua grande maioria pela variação litológica e pelos lineamentos. Desta maneira, a bacia hidrográfica do Rio Taturi, apesar de sua morfologia de baixo declive, possui características morfológicas e, portanto, processuais, variadas, as quais estão vinculadas à litologia e aos lineamentos. Assim, os setores de domínio de litologias arenosas apresentam morfologias que indicam maior intensidade dos processos erosivos, o que deve ser considerado quando do uso e ocupação da terra.

Made available in DSpace on 2022-04-28T19:41:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-07-01 This study aimed to discuss the coastal geomorphological dynamics and their implications for the adequate management. Thus, from the geomorphological mapping, the morphodynamic processes that characterize the relief compartments are pointed out and important aspects to proper planning of these terrains. The study area covers the municipalities of the Costa das Baleias Region (south coast of Bahia State), geomorphologically marked by Coastal Tablelands. The lack of studies on this scenario, very frequent on the Brazilian coast, justified our choice, in order to contribute effectively to the study of these environments. The geomorphological map was prepared based on aerial photographs with a scale of 1: 25,000 and field data. The results showed the concentration of erosional forms on the exposed slopes to the east/southeast tablelands. In addition to the trays, there are alluvial terraces and quaternary coastal plains that demonstrate morphologies still in the sedimentation phase, a fact that determines limitations for use due to the instability of the terrain and the occurrence of periodic flooding. Thus, this work intends to subsidize planning proposals for the land use and occupation of Coastal Tablelands. Colegiado de Geografia Universidade Federal do Vale do São Francisco - UNIVASF. Senhor do Bonfim Instituto de Geociências e Ciências Exatas Universidade Estadual Paulista Júlio de Mesquita Filho - UNESP Departamento de Geografia Instituto de Geociências Universidade Estadual de Campinas - UNICAMP Instituto de Geociências e Ciências Exatas Universidade Estadual Paulista Júlio de Mesquita Filho - UNESP

Made available in DSpace on 2022-04-28T19:41:55Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 The alterations caused by the man in the landforms have been dynamized during the process of urban growth, resulting different environmental damages mainly intensification of erosive process, silting of rivers and consequently the occurrence flooding. Thereby, the aim of this work is to analyze the alterations caused by the urban growth of Araras city (SP) in the slopes of low course of Facão’s stream watershed from 1997 to 2016. To understand the geomorphological implications coming from anthropogenic activities in the study area in this time, the principles of Systems General Theory which allowed the comprehension of area as controlled system due to anthropic interference. The confection of geomorphological map, land cover map and declivity map as well as fieldwork allowed to collect data whose analyses made it possible to identify the geomorphological features brought by the urban growth. Therefore, the main changes observed refer to alteration in the feature of waterway due to process of channeling, decrease natural topographic breaks and advent erosive features. Universidade Estadual Paulista-UNESP UNESP Universidade Estadual Paulista-UNESP UNESP

Made available in DSpace on 2021-06-25T10:30:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 The geomorphological cartography at a scale of detail in the Brazilian semiarid presents several aspects to be considered, in order to consistently subsidize geomorphological research in local contexts. In this paper, we aim to present a methodological proposal for detailed geomorphological mapping in crystalline sectors of the Sertaneja Depression (Brazilian semi-arid), developed through a case study. The methodological procedures involved the preparation of the database, analysis of pre-existing geomorphological mapping manuals, fieldwork, elaboration of the geomorphological interpretation key, and the graphic representation of the landforms. In this way, morphographic and morphometric attributes were represented, as well as hydrography, topography, anthropogenic landforms, lithology, chronology, and structural elements. The geomorphological mapping contributed to the understanding of the spatial organization of landforms in the study areas, in addition to contributing to the interpretation of geomorphological facts. Thus, we believe that technical procedures can be used in similar areas or even adapted to different contexts in the semiarid itself. Universidade de Pernambuco (UPE) Departamento de Geografia Universidade Estadual Paulista (UNESP) Departamento de Geografia e Planejamento Ambiental Universidade Estadual Paulista (UNESP) Departamento de Geografia e Planejamento Ambiental

Made available in DSpace on 2021-06-25T10:21:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) A B S T R A C T The relief of São Paulo is characterized by the presence of long cuesta, whose origin causes discussion until the present day. Thus, the objective of this research is to analyze the morphostructural characteristics of the Passa Cinco River watershed, situated at transition zone of Cuestas-Peripheral Depression, constituting significative example of this relief system, taking in consideration the complexity of existing forms, that include extense continuous cuesta scarp and buttes of different sizes, extensions and characteristics. The data to analyze the study area were obtained through the integrated interpretation of the Geomorphological, Declivity, Drainage Density, Depth of Drainage and Lineation maps, in 1:50.000 scale. Beyond circumdenudation, considered the classic process of origin of these two relief macrocompartments, tectonic factors also need to be evaluated in order to have a better understanding of these relief forms. These factors are responsible for the acceleration of erosive processes promoted by river courses in some sectors, collaborating with the circumdenudation process, as with the local variation of the Cuesta Front and buttes. Thus, it is understood that the technical procedures allowed to obtain data that demonstrate the complexity involved in the elaboration of the relief in this transition sector, being able to be extended to others areas of the interior of the state of São Paulo with this same relief characteristics. UNESP Campus de Rio Claro, Avenida 24A n. 1515 UNESP Campus de Rio Claro, Avenida 24A n. 1515 CNPq: 155332/2016-3 FAPESP: 2016/25231-1

As imagens orbitais disponibilizadas gratuitamente por meio de globos digitais têm auxiliado diversas pesquisas geomorfológicas, principalmente em regiões com pouca cobertura de produtos em nível de detalhe. Nesse trabalho, foram utilizadas imagens orbitais disponibilizadas pelo Google EarthTM, como forma de avaliar a sua aplicabilidade no mapeamento de feições antrópicas em rede de drenagem no semiárido brasileiro. Por meio de diferentes imagens, foi possível a classificação dos segmentos de drenagem, a identificação de pequenos barramentos e cacimbas em escala temporal e em nível de detalhe. Ainda, as imagens auxiliaram na interpretação de processos geomorfológicos antropogênicos, típicos de drenagens com características similares.

Made available in DSpace on 2020-12-10T19:40:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-10-01 Ephemeral drainage basins and their alluvial deposits may have characteristics that contribute to the understanding of Holocene time-scale climate dynamics. Although widely studied in semiarid contexts of different countries, their paleoclimatic significance is still poorly understood in Brazil. In this research, we analyzed the characteristics of alluvial deposits in two small drainage basins, located in the southern semi-arid, central-north sector of the Sertaneja Depression - State of Bahia/Brazil. Our purpose also included interpreting the Holocene climatic conditions that contributed to the processes of alluvial deposit formation. We performed the geomorphological mapping, allostratigraphic layers identification on field trip, Particle Size Distribution (PSD) analysis, sediment morphology analysis, and Optically Stimulated Luminescence (OSL) dating. Alluvial deposits showed characteristics associated with crystalline rocks and ephemeral streams such as [i] spatial discontinuity along the drainage channel; [ii] depositional architecture indicative of bedding lateral migration and laminar flows; [iii] predominance of gravel and coarse sand, poorly sorted and; [iv] statistical parameters that suggest past episodes flows. The depositional events occurred in the Middle Holocene - Upper Holocene transition, between 4.4 kyr - 3.5 kyr B.P. and between 1.1 kyr B.P. to the present. These deposits have relations with dry climatic conditions established in the last 4 kyr. Univ Estadual Julio Mesquita Filho, Dept Geog, Av 24 A,1515, BR-13506900 Rio Claro, SP, Brazil Univ Estadual Julio Mesquita Filho, Dept Planejamento Terr & Geoproc, Av 24 A,1515, BR-13506900 Rio Claro, SP, Brazil Univ Estadual Julio Mesquita Filho, Dept Geog, Av 24 A,1515, BR-13506900 Rio Claro, SP, Brazil Univ Estadual Julio Mesquita Filho, Dept Planejamento Terr & Geoproc, Av 24 A,1515, BR-13506900 Rio Claro, SP, Brazil

Made available in DSpace on 2019-10-05T04:09:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-09-01. Added 1 bitstream(s) on 2021-07-15T15:05:01Z : No. of bitstreams: 1 S1413-41522018000500923.pdf: 4842619 bytes, checksum: 41954fdbb7e0a4e0ea55e34ef13447ef (MD5) In this paper, infiltration distribution rates were evaluated on areas affected by accelerated erosive processes and covered by anthropogenic material. Infiltration tests were performed at several samples distributed in the area. The data were adjusted to the Horton decay function, and its parameters were correlated with attributes of the physical environment and the terrain digital model, using the Pearson correlation coefficient (r). Results pointed out great variability of infiltration rates, due to the complexities generated by several structural interventions in the different sectors sampled, with different morphological, granulometric and land use variables. The analysis made sector by sector here proposed allowed verifying the main variables that interfere in the parameters that represent the infiltration rates, in spite of the spatial variability for infiltration rates. In low-slope sectors, there was a strong correlation between infiltration rates and sand, as well as between these rates and river distance. In high slope and grassland areas, such correlations are high between the final infiltration rates and the fine materials (clay and clay + silt). In high-slope areas with no vegetation coverage, the strongest correlations occur between the final infiltration and the cumulative runoff flow. Therefore, results here presented emphasize that both the characteristics of the cover materials and the morphology of the land are determinant for data analysis. Univ Fed Mato Grosso, Cuiaba, MT, Brazil Univ Estadual Paulista, Rio Claro, SP, Brazil Univ Estadual Paulista, Rio Claro, SP, Brazil