Landscape forms through drone documentation: rediscovering continuity of Torto river in Braga District, Portugal

This article proposes a proof of concept related to a methodology that uses an unmanned aircraft vehicles (UAV) as an investigation tool in landscape planning, which results can be used also in archaeology, cultural landscape, and heritage studies, to create a multidimensional approach for understanding relations between valuable assets and preserve fundamental qualities of the landscape. It is evaluated if UAV is appropriate as a research tool (through accessibility of equipment, software, and workflows of its application) capable of providing multidimensional views of the landscape that could be used to anticipate planning decisions. As an example, the Torto River, located in Braga, Portugal, starting from its intersection with Roman Via XIX, was studied. Research aims to show that the drone surveying can lead to raised awareness on disappearing continuity of landscape elements, and the value of their spatial relationships, which are not taken into consideration in development of places like researched area neighbouring nuclei of S. Frutuoso and Dume, nearby popular pilgrimage trail Camino de Santiago. The possibility of identifying and reflecting on the elements that ensure continuity of landscape is noted through videography recorded based on the visual line of sight (VLOS) mode. The research explores a variety of conditions that should be considered when preparing for research and recording chosen information (as local regulations, weather conditions, expected outputs), proposing a methodology of flight planning and execution with the most optimal setups, including –15° angle for capturing landscape elements and their relationship, and – 90° for photogrammetry and videogrammetry (here captured in maximal altitudes allowed for the research area, not overstepping 75 and 120 m limit).

This publication is based upon work from Lab2PT (Laboratório de Paisagens, Património e Território) research group at the University of Minho, Portugal. Part of the research was realised thanks to the grant with reference number: Lab2PT/UIDB-04509/11 funded by national funds (PIDDAC) and FCT/MCTES.