Tese
Aplicabilidade de imagens obtidas a partir de aerofotogrametria realizada com aeronave remotamente pilotada como subsídio à gestão ambiental
Fecha
2019-02-27Autor
Avila, Calinca Barão de
Institución
Resumen
The increasing use of natural resources, considering the significant impacts on the
environment that may result from this use, implies the need for carrying out studies,
especially using new technologies to understand these impacts broadly, thus
supporting the environmental management and indicating alternatives to minimize
adverse environmental effects. The justification for developing this doctoral
dissertation is based on these environmental issues and it focuses on the use of
remote sensing technology as a tool for the generation of aerial images with high level
of detail from the use of Remotely Piloted Aircraft (RPA). The purpose of this study
was to evaluate the applicability of the information obtained from RPA images for the
elaboration of environmental diagnosis as a support to the improvement of the
environmental management, considering the technical issues of the flight. Two sample
areas with different characteristics (vegetation and water physiognomy, and variation
in ground slope) were selected. The flights were carried out in both areas at heights of
50 m, 80 m and 110 m in relation to the ground level at a reference point; ground
control points were used in both areas. In the next step of the flight execution, the
Agisoft Photoscan software was used to process the images and to obtain the
products, orthophotomosaic and Digital Elevation Model - DEM. After that, statistical
analyzes of the data from the products were carried out to evaluate the accuracy in
situations of using or not the ground control points, and the classification of the
products according to the Brazilian Cartographic Accuracy Standard of Digital
Cartographic Products (PEC-PCD), by the use of GeoPEC software. It was also
verified the accuracy of flight heights regarding the classification of ground covering
physiognomies using the Support Vector Machine algorithm in R programming
language. The results obtained in this study converge to the need of using ground
control points to obtain more accurate products, when necessary. In addition,
according to the assessments of the planialtimetric positional accuracy of the products
for the different flight heights, it is suggested that the flights should be executed at 80
m and 110 m. Regarding the results of physiognomy classification, flight heights of 80
m and 110 m did not differ statistically. In this context, considering other technicaleconomic
aspects (coverage area, flight autonomy, data processing time in the
software), it is possible to indicate that the flight at 110 m has better efficiency for the
generation of orthophotomosaic as a support for environmental management.