Métodos de levantamentos topográficos por sensores de radar da bacia hidrográfica do Rio Capivara, Botucatu-SP.

The objective of the present study was to analyze the quality and accuracy of the data generated by radar sensors, which offer the Digital Elevation Model (MDE) and its local derivations, comparing by means of the Kappa index its accuracy to the topographic truth Of the catchment area of the Capivara watershed. A detailed analysis was performed to detect, improve, validate and correct some errors related to the altimetric dimensions belonging to the respective level curves, where the TIN interpolation tool (irregular mesh of triangulation) was applied, thus generating the Digital Elevation Model (MDE) in matrix format representing the Earth Truth. The TOPODATA database altimetry MDE was imported into the QGIS 2.2.0 software, isolating the areas of real interest, resulting in a new representative matrix file for crossing the matrix of confusion and validation through the Kappa Index. Some places with flat relief, such as the case of classes 1 and 2, TOPODATA presented some overestimations of the topographic classes and, in relation to areas with rugged relief and marked slope, the data analyzed showed an underestimation of the topographic classes. Based on the results obtained, the evaluation of the accuracy of TOPODATA processed to the Topographical Truth of the Capivara watershed presents a MDT of good classification with more than 50%, which enables such a product as an economically feasible and fast alternative for mapping and environmental modeling .