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[EN] The three-dimensional (3D) visualization of historical and cultural heritage in the province of Cáceres is essential for tourism promotion. This study uses panoramic spherical photography and terrestrial laser scanning (TLS) for the geometric characterization and cataloguing of sites of cultural interest, according to the principles of the Charter of Krakow. The benefits of this project include improved knowledge dissemination of the cultural heritage of Cáceres in a society that demands state-of-the-art tourist information. In this sense, this study has three specific aims: to develop a highly reliable methodology for modeling heritage based on a combination of non-destructive geomatics methods; to design and develop software modules for interactive 3D visualization of models; and to promote knowledge of the historical and cultural heritage of Cáceres by creating a hypermedia atlas accessible via the Internet. Through this free-of-charge hypermedia atlas, the tourist accesses 3D photographic and interactive scenes, videos created by 3D point clouds obtained from laser scanning and 3D models available for downloading in ASCII format, and thus acquire a greater knowledge of the touristic attractions in the province of Cáceres., [ES] La visualización tridimensional (3D) del patrimonio histórico-cultural en la provincia de Cáceres es una herramienta vital para su promoción turística. Este trabajo emplea la fotografía panorámica esférica y el uso del escáner láser terrestre para la caracterización geométrica de los bienes de interés cultural, así como su catalogación, de acuerdo a los principios de la Carta de Cracovia. El beneficio de este proyecto es alcanzar un mayor conocimiento del patrimonio cultural de Cáceres para una sociedad que demanda información turística actualizada. En este sentido, hay tres objetivos específicos en el trabajo: desarrollar una metodología de alto grado de fiabilidad para la modelización del patrimonio basado en la combinación de diferentes métodos geomáticos no destructivos; diseñar y desarrollar módulos de software para la visualización interactiva de modelos 3D; y promover el conocimiento del patrimonio histórico de Cáceres mediante la creación de un atlas hipermedia accesible en Internet. A través del atlas hipermedia, el turista accede gratuitamente a los escenarios fotográficos tridimensionales e interactivos, los videos a partir de las nubes de puntos 3D adquiridas con láser escáner y a la descarga de los modelos 3D en formato ASCII, adquiriendo un mayor conocimiento de los atractivos turísticos de la provincia de Cáceres.

At present there is a wide variety of geomatic techniques available to determine the dynamics of glaciers, rock glaciers and ice patches. Between 1991 and 2012, different geomatic techniques – total station, global positioning system, close-range photogrammetry and terrestrial laser scanner – were applied to monitor the movement of cryosphere landforms in the high mountains of the Iberian Peninsula. The applied techniques must be adapted to the dynamic conditions of cryospheric environments, and so there is no ideal general technique, and depending on the characteristics of the geomorphological structure to be studied, different geomatic techniques can be used. However, there are situations in which certain instruments cannot be used: global positioning system–real time kinematics shows difficulties when the presence of vertical walls cause a ‘multipath’ effect. The technique that provides the best results in each case must be chosen, although they can all give good results in measuring and monitoring geomorphological processes. This paper analyses the techniques used and results on vertical and horizontal changes of glaciers, rock glaciers and ice patches in the Sierra Nevada, Pyrenees and Picos de Europa, and differences among them by location and topoclimatic setting. All glaciers and rock glaciers show a thinning tendency and annual variations in the flow velocity. In addition to the specific dynamic analysis, the geomatic techniques can be used to detail scale and volume changes and perimeter of the analysed landforms.

[EN] The detailed description of processing workflows in Structure from Motion (SfM) surveys using unmanned aerial vehicles (UAVs) is not common in geomorphological research. One of the aspects frequently overlooked in photogrammetric reconstruction is image characteristics. In this context, the present study aims to determine whether the format or properties (e.g., exposure, sharpening, lens corrections) of the images used in the SfM process can affect high-detail surveys of complex geometric landforms such as rock glaciers. For this purpose, images generated (DNG and JPEG) and derived (TIFF) from low-cost UAV systems widely used by the scientific community are applied. The case study is carried out through a comprehensive flight plan with ground control and differences among surveys are assessed visually and geometrically. Thus, geometric evaluation is based on 2.5D and 3D perspectives and a ground-based LiDAR benchmark. The results show that the lens profiles applied by some low-cost UAV cameras to the images can significantly alter the geometry among photo-reconstructions, to the extent that they can influence monitoring activities with variations of around ±5 cm in areas with close control and over ±20 cm (10 times the ground sample distance) on surfaces outside the ground control surroundings. The terrestrial position of the laser scanner measurements and the scene changing topography results in uneven surface sampling, which makes it challenging to determine which set of images best fit the LiDAR benchmark. Other effects of the image properties are found in minor variations scattered throughout the survey or modifications to the RGB values of the point clouds or orthomosaics, with no critical impact on geomorphological studies.