Susceptibilidade à erosão na alta bacia do ribeirão Barreiro – Alexânia-GO

• Autor(a) principal: Medeiros, Glacielle Fernandes
• Data de Publicação: 2014
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• dARK ID: ark:/38995/0013000003952
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/4374
• topic: Susceptibilidade à erosão; Escoamento superficial; Erodibilidade; Erosive susceptibility; Runoff; Erodibility; ENGENHARIA CIVIL::GEOTECNICA

The present research inserts in the Project “Mapping and Geological and Geotechnical Characterization Applied in Assessing the Erodibility of Unconsolidated Material Along the Stretch of Duct OSBRA from Petrobras”. Sand river watershed is crossed by this stretch of ducts highlights, relatively, for the occurrence of accelerated erosive focuses. Soil water erosion is composed by a natural process, which occurs regards weather factors, geological, geomorphological and pedological. However, water erosion may by intensified by anthropic modification in one of this factors, becoming an accelerated process. Runoff may be considered part of water erosion process, which has its main origin in precipitations, over specific unconsolidated material, with specific disaggregation resistance and transportation (erodibility), located in specific form of terrain. In this context, this research aims the investigation of the terrains of the upper watershed of Barreiro creek, affluent located in the medium course of Areias river, in the county of Alexânia – GO, about erosion susceptibility, with emphasis in runoff in relation to erodibility of existing unconsolidated material. To achieve such goals, equipment like high precision GPS were used, for tracking, from the fast static method of the sample points and the stop and go method on the back road which gave access to the watershed limits and its interior, besides digital modeling of morphometric variables which interferes in runoff. In the same way, samples were collected and points observed, for non-alleatory characterization of the study area, from the rational method, as suggested by Zuquette and Gandolfi (2004). This research aimed to analyze soils resistance toward disaggregation and material transportation, related to runoff, with specific geotechnical tests, associated to basic cartographic documentation. Those consisted in Inderbitzen tests and disaggregation, in collected samples on chosen points according to different slopes, associated with erosive focuses occurrence. As results, were compiled and developed cartographic products such as: unconsolidated material maps, documentation, slope, curvatures, hipsometrics, soil use and occupation, susceptibility and potential to laminar and linear erosive process. During the test Inderbitzen was observed that the behavior of materials in relation to the slope of the standard ramp (10 °) and similar to the field slope better reflected the susceptibility of materials in the second case, showing greater loss of material at higher inclinations . As for the disaggregation test, the sample lateritic proved more resistant to flooding processes than saprolítica sample, both processes by total immersion, as the processes by partial immersion. During the disintegration test and the result Inderbitzen occur as expected, ie lateritic samples showed to be more resistant, especially because of cohesive forces existing in these types of soil.