Erosion Assessment at Earthen Archeological Sites by Morphometric Analysis of Digital Surface Models: The Case of Huaca Fortaleza (Pampa Grande, Peru, 600–750 AD)

GIS-based assessment of soil erosion risk in a post-nuclear landscape: A morphometric approach using ALOS PALSAR DEM

Morphometric analysis of terrain is widely recognized as one of the most effective approaches to investigating soil erosion processes. This study examines the relationship between terrain morphometry and soil erosion susceptibility within the Semipalatinsk Test Site (STS), Kazakhstan, using the ALOS PALSAR digital elevation model (DEM) at 12.5 m spatial resolution processed within ArcGIS 10.4. A series of thematic morphometric maps – including hypsometric, slope gradient, and slope aspect layers – were generated and used to develop a three-level hierarchical classification of theResults indicate that flat and very gentle terrain (slopes below 6°) accounts for approximately 51% of the STS territory; gentle to moderate slopes (6° – 25°) cover 44%; and steep slopes (above 25°) occupy only approximately 5% of the total area, concentrated within the Degelen Mountain Range. The dominant slope aspect is north-facing, contributing to pronounced microclimatic asymmetry. Integration of GIS-based morphometric parameters with land cover and soil data revealed distinct erosion-prone zones correlated with slope steepness and relative relief. The findings confirm that high-resolution DEM-based morphometric analysis is a reliable and efficient tool for landscape assessment, soil erosion monitoring, and sustainable land management planning in semi-arid regions with complex topography.

Spatially Explicit Erosion Severity as a Proxy for Landslide Susceptibility in a Mountainous Watershed

Mountainous watersheds often suffer from incomplete and spatially biased landslide inventories, which limit the reliability of conventional susceptibility modelling. This study examines whether the erosion coefficient Z of the Gavrilović Erosion Potential Method can provide a process-oriented indicator of slope-instability predisposition in the Portaikos watershed, Central Greece. The Z coefficient was derived from geospatial layers representing vegetation protection, lithological erodibility, erosion-process expression and slope gradient, using Copernicus land-cover products, tree-cover density data, Sentinel-2 imagery, FABDEM and national soil–geological information. A landslide inventory of 46 mapped occurrences from the Hellenic Survey of Geology and Mineral Exploration was then used as an independent reference layer. Erosion severity was classified into five classes and compared with the landslide distribution through Frequency Ratio analysis. Most of the basin was assigned to moderate, very slight and slight erosion classes, covering 34.7%, 30.1% and 28.2% of the area, respectively. By contrast, severe and excessive erosion occupied only 6.7% and 0.4% of the watershed, but contained a much larger proportion of the mapped landslides: 58.7% and 10.9%, respectively. This disproportion was also reflected in the Frequency Ratio analysis. When the severe and excessive classes were considered together, they occupied approximately 7.1% of the watershed but contained 69.6% of the mapped landslides, corresponding to an FR value of 9.79. The separate excessive class showed the highest FR, but it was interpreted cautiously because of its very limited spatial extent and small landslide count. These results indicate that high Z values coincide with terrain sectors where lithological weakness, steep slopes, reduced surface protection and erosion-related sediment-source conditions jointly favour slope instability. The Gavrilović Z coefficient should therefore not be interpreted as a substitute for rainfall-threshold analysis or inventory-based predictive models. Rather, it may serve as a useful first-order screening layer for field verification, spatial prioritization and ecosystem-based mitigation planning in data-scarce Mediterranean mountain watersheds.

Spatial assessment of soil erosion through the application of the RUSLE model and geospatial technologies in the upper and middle reaches of the Tafna watershed (northwestern Algeria)

Evaluating Slope Instability in a Volcanic Caldera Environment Using GIS-Based 3D Analysis: Mt. Bawakaraeng, South Sulawesi

Landslides in volcanic terrains pose significant hazards to downstream communities, infrastructure, and watershed systems, particularly where steep slopes and complex geological conditions coexist. This study presents a GIS-based three-dimensional (3D) deterministic slope stability analysis to evaluate landslide susceptibility within the Mt. Bawakaraeng caldera, Sulawesi Island, Indonesia. The analysis integrates geotechnical, geological, hydrological, and topographic parameters obtained from field investigations, laboratory testing, remote sensing data, and a high-resolution 5-m Digital Elevation Model (DEM). Slope stability was evaluated using the factor of safety (FS), calculated through a Hovland-based 3D column method implemented within a GIS environment. Two critical collapse zones were identified and corresponded closely with documented historical landslide events. The calculated minimum FS values of 0.825 and 1.000 indicate unstable to marginally stable slope conditions, respectively. Numerical simulations indicate a progressive failure mechanism in which the collapse of a major slope unit can reduce the stability of adjacent slope units, potentially generating cascading landslide events. Monte Carlo simulations were additionally employed to identify critical slip surfaces and assess potential failure configurations. The simulated slip surfaces showed good agreement with observed landslide morphologies, supporting the reliability of the modeling approach. Potential failure volumes were also estimated to assess the downstream sediment hazard to the Jeneberang watershed. The results demonstrate that integrating GIS, high-resolution terrain data, and 3D deterministic modeling provides an effective framework for spatially explicit slope stability assessment in complex volcanic environments. The approach can support landslide hazard mitigation, watershed management, infrastructure planning, and sustainable development in mountainous regions prone to slope failure.

Palaeo-Glacier Reconstruction and Surface Dynamics Analysis of Nef Glacier (Chile) Using Automated Open-Source Tools Based on Sentinel-1 Imagery and Digital Elevation Models

Evolution and Analysis of Landslides in Lowland Areas: The Case Study of Reuil in the Champagne Vineyard Region (Marne, France)

The slopes of the Champagne vineyards are regularly affected by landslides. Given the high societal and economic stakes, these processes cause significant damage and pose a major challenge for the wine industry, forestry and heritage preservation. Numerous studies have already been conducted to understand their behavior and hydrodynamic functioning. They show varied morphologies and a dominant influence of water resources. However, this forcing does not explain the spatial distribution of current landslides, which occur in upper-slope positions, on the steepest terrain recently planted with vines. Using the two shallow landslides at Reuil, located in the heart of the Marne Valley in the Champagne vineyards, as a study site, recent landslide activity is analyzed through a comparative analysis of three DTMs derived from LiDAR HD data and two UAV photogrammetric surveys. This study reveals the affected areas and displaced volumes, which can reach up to 900 m3. Landslide activity was then correlated with regional climatic data. This research shows that landslides are more likely to occur during a period of excessive rainfall following a drier period. Diachronic analysis of aerial images also demonstrates the influence of land use on landslide activity. In particular, land clearing and vineyard operations on the steepest plots constitute a significant anthropogenic forcing affecting slope stability. Taken together, these results provide greater insight into the changing geomorphological dynamics of the Champagne vineyards. On the one hand, they clarify how landslides occur at vineyard plot scale. On the other hand, they provide initial insights into the resilience of stakeholders (winegrowers, etc.) affected by these instabilities.