This article juxtaposes results from an unmanned aerial vehicle (UAV) and a terrestrial laser scanning (TLS) survey conducted to determine land relief. The determination of terrain relief is a task ...that requires precision in order to, for example, map natural and anthropogenic uplifts and subsidences of the land surface. One of the problems encountered when using either method to determine relief is the impact of any vegetation covering the given site on the determination of the height of the site's surface. In the discussed case, the site was covered mostly in low vegetation (grass). In one part, it had been mowed, whereas in the other it was 30–40cm high. An attempt was made to filter point clouds in such a way as to leave only those points that represented the land surface and to eliminate those whose height was substantially affected by the surrounding vegetation. The reference land surface was determined from dense measurements obtained by means of a tacheometer and a rod-mounted reflector. This method ensures that the impact of vegetation is minimized. A comparison of the obtained accuracy levels, costs and effort related to each method leads to the conclusion that it is more efficient to use UAV than to use TLS for dense land relief modeling.
The authors undertook to examine and analyse the changes in the relief in Łódź city centre over a period of over one hundred years. Archival cartographic resources containing morphometric information ...and contemporary laser scanning data (LIDAR) are used to analyse changes. This required appropriate transformation of these data to generate a differential relief map. Information on the geographical environment (waters, relief) is linked to the spatial development of the city. The analyses revealed several characteristic types of changes occurring in the area, which are presented in the form of case studies.
The selection of appropriative geomedia attributes for constructing natural and suggestive perspective visualizations of historical non-cartometric manuscript topographic works is investigated, to ...enable an intuitive perception of relief landforms. The main objective of the study is to demonstrate geomedia parameters for representing the third dimension in topographic watercolor maps from the eighteenth century, using cartographic rules and geoinformation operations for transforming graphic means of expression. The following methods were used: the choice of representative map fragments with specific painterly means of expression; the analysis of main relief forms on historical and modern maps; the rectification; vectorization of contour lines, and the transformation to a GRID model; the use of parameter variations: elevation rise, azimuth and altitude, contrast of illumination; and the creation of the final bird’s-eye-view visualization, with appropriate parameters. It is found that the parameters for the visualization of the non-cartometric water-colored topographic image on a 3D model can be selected in turn. However, what matters is maintaining their complementarity. The proposed parameters for the three maps work well for creating the general static bird’s-eye-view visualization, with the natural and suggestive perception of the landscapes’ relief.
The paper presents a range of geomorphometric analyses of Polish territory using both classical and new approaches. The classical outcomes include maps of hypsometry, relative altitude, angle of ...slope and exposure, as well as altitudes broken down into ranges and angle of slopes in percentages broken down by administrative province. The new approach included the presentation of land relief through standard deviations of relative elevation in regular geometric fields. Maps of hypsometry, elevation difference, angle of slope, exposure and standard deviation were also presented. The survey involved elevation data from the SRTM-3 satellite with a resolution of 3x3' (60-65x90 m), which were converted for research purposes into a grid of 125x125 m and then into hexagons with a surface area of 0.14 and 3 km1. This level of detail makes the data particularly useful in morphometric analyses, including in applied research. Certain terrain coverage elements, such as forests, especially in lowland and flatland areas, affected the data and would have to be filtered out in applications requiring even higher accuracy.
Extract from the Proceedings of the Malaga Society of Physical and Natural Sciences
Memoirs of the Geological Institute of Spain/by Domingo de Orueta
Artificial selection points for the province of ...Malaga/by Luis Parody
Extracto de las Actas de la Sociedad Malagueña de Ciencias Fisicas y Naturales
Ded. autógr. del aut.
Memorias del Instituto Geologico de España / por Domingo de Orueta
Apuntes de seleccion artificial para la provincia de Malaga / por Luis Parody
Caracteristicas geologicas de los materiales bituminosos de la Serrania de Ronda (Malaga) / por Francisco Hernandez Pacheco
Land Reliefs That Are True to Nature Curtis, George Carroll
Bulletin of the American Geographical Society,
01/1911, Volume:
43, Issue:
6
Journal Article
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