Geomorphology-oriented digital terrain analysis: Progress and perspectives

Abstract

Digital terrain analysis (DTA) is one of the most important contents in the research of geographical information science (GIS). However, on the basis of the digital elevation model (DEM), many problems exist in the current research of DTA in geomorphological studies. For instance, the current DTA research appears to be focused more on morphology, phenomenon, and modern surface rather than mechanism, process, and underlying terrain. The current DTA research needs to be urgently transformed from the study of landform morphology to one focusing on landform process and mechanism. On this basis, this study summarizes the current research status of geomorphology-oriented DTA and systematically reviews and analyzes the research about the knowledge of geomorphological ontology, terrain modeling, terrain derivative calculation, and terrain analytical methods. With the help of DEM data, DTA research has the advantage of carrying out geomorphological studies from the perspective of surface morphology. However, the study of DTA has inherent defects in terms of data expression and analytic patterns. Thus, breakthroughs in basic theories and key technologies are necessary. Moreover, scholars need to realize that DTA research must be transformed from phenomenon to mechanism, from morphology to process, and from terrain to landform. At present, the research development of earth science has reached the critical stage in which the DTA research should focus more on geomorphological ontology. Consequently, this study proposes several prospects of geomorphology-oriented DTA from the aspects of value-added DEM data model, terrain derivatives and their spatial relations, and macro-terrain analysis. The study of DTA based on DEM is at a critical period along with the issue on whether the current GIS technology can truly support the development of geography. The research idea of geomorphology-oriented DTA is expected to be an important exploration and practice in the field of GIS.

Gully Erosion Susceptibility Mapping in Highly Complex Terrain Using Machine Learning Models

“…The spatial resolution of all the factors we used was 1 m, at which scale it might be challenging to avoid the influence of the micro-topography on the analysis [59]. Some studies have shown that the best resolution did not necessarily provide the best information [35].…”

“…With the development of fine-resolution images all over the world [59], large-scale modeling of gully maps will be possible and would be an urgent need for research and management. The results of this research offered a time-efficient, interpretable, and relatively accurate method for gully mapping and would be well applied in future large-scale gully modeling.…”

OBIA-Based Extraction of Artificial Terrace Damages in the Loess Plateau of China from UAV Photogrammetry

“…The development of unmanned aerial vehicle (UAV) photogrammetry and light detection and ranging (LiDAR) remote sensing can guarantee the data accessibility of high-resolution images. Unlike satellite-based sensors, both aforementioned approaches can create high-resolution topographical data and orthophoto images [42] and simultaneously realise field survey and remote sensing [43,44]. Amongst both approaches, UAV photogrammetry is more flexible and entails a lower cost compared with LiDAR [45].…”

Quantification of Loess Landforms from Three-Dimensional Landscape Pattern Perspective by Using DEMs

“…For a long time, people have been committed to improving the methods of describing and expressing landforms to satisfy the requirements of practical applications, such as textual description, pictographic mapping, and contour maps [9]. Nevertheless, the previous methods are mainly for finer visualization of the landforms, and most of the descriptions of the landforms are qualitative [10,11].…”