Applications of photogrammetry for environmental research (Editorial)

The applications of photogrammetry for environmental research benefits from the continuous and rapid evolution of sensors and methodologies in this field. The support of photogrammetric tools to a very wide range of research activities was previously confined to geomatic disciplines and the methodologies strictly based on terrestrial or traditional aerial photogrammetry. However, the timely investigation of natural or anthropogenic phenomena required more flexible tools and the ability of geoscientists and researchers involved in the study of natural resources to exploit photogrammetric methodologies in a more flexible way. In the last decade, new opportunities came from the possibility to acquire images using low-cost non-metric cameras from low-altitude unmanned aerial vehicles (UAVs), or fixed locations in terrestrial surveys, with a successive highly automated processing strategy. For instance, a huge amount of papers in the recent scientific literature refers to the structure from motion (SfM) technology in the reconstruction of three-dimensional features at very high spatial and temporal resolutions and with a surprisingly high positional accuracy. Point clouds obtained from best practices in novel approaches of close-range photogrammetry has proven to be of compatible spatial resolution and accuracy of those provided by terrestrial laser scanning and, very often, photogrammetry and laser scanning are combined to enhance the qualities of each other. The Special Issue aimed for papers including novelties and advances on the use of recent photogrammetric approaches to a wide range of environmental studies, including the following: photogrammetry for monitoring; UAV photogrammetry for environmental research; photogrammetry for disaster prevention and management; photogrammetry for real-time mapping; merging of data from dierent survey technologies; and novel uses of proximity surveys to geography, geomorphology, geotechnologies, landscape description, coastal studies, archaeology, etc.