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

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)

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.

Assessment of annual soil loss and soil erosion susceptibility in a tropical sub-basin of the Western Ghats, Southern India using RUSLE and AHP

The Western Ghats (WG) of southern India represent a geomorphologically sensitive terrain where soil erosion and landslides constitute major geohazards. The Chittar sub-basin (CSB) of the Achankovil River Basin (ARB) was selected for investigation owing to its steep slopes, high-intensity rainfall, and increasing anthropogenic pressure, which together accentuate erosional processes. This study employs remote sensing and GIS techniques in conjunction with the Analytical Hierarchy Process (AHP) and the Revised Universal Soil Loss Equation (RUSLE) to quantify annual soil loss and delineate erosion susceptibility zones. High erosion affects 684.11 ha (24.8%) of the basin, whereas low erosion is observed across 780.03 ha (28.3%). Multicriteria evaluation indicates that vegetation cover (NDVI), rainfall, soil texture, soil depth, slope, aspect, and elevation exert the greatest influence on erosion susceptibility. Spatial analysis reveals that the western sector of the basin is most vulnerable, the central region exhibits moderate susceptibility, and the northwestern part remains comparatively stable. The results provide a process-based understanding of erosion dynamics in tropical high-relief basins and furnish a decision-support framework for prioritizing soil and water conservation strategies in the WG.

Prioritizing soil erosion susceptible region of Kempty watershed-based on morphometric, hypsometry, forest, and soil using multi-criteria analysis

Soil erosion is the main driving force of several devastating natural hazards in the complex mountainous terrain of the Himalayas. The significant impact of soil erosion includes poor soil productivity and soil type, degraded water quality, land degradation, sedimentation, siltation and ultimately biodiversity losses. Hence, it is necessary to assess soil erosion and prioritize the susceptibility regions for effective control measures to serve as baseline data. The present study attempted to analyze the various morphometric, forest, and soil type parameters through Geographical Information System (GIS) and Multi-Criteria Analysis (MCA) techniques for the identification of soil erosion susceptible regions in forest-imparted Kempty watershed, Mussoorie (Dehradun, Uttarakhand, India). The watershed has been divided into four sub-watersheds (SWS1, SWS2, SWS3, and SWS4) using topographic maps (1:50,000 scale and 20 m contours) and ASTER DEM (30 m resolution). Ranking sub-watersheds that significantly influence erosion has been done based on the integrated analysis of morphometric parameters with forest cover, slope, soil, and hypsometric parameters using MCA. Ranks were integrated with MCA to give in four major classes, i.e., classified from 1 to 4 in which, rank 1 indicates the highest priority; while 4 indicates the lowest priority. Notably, MCA priority ranks depicted that SWS4 has the lowest Cp value (2.27) followed by SWS1 (2.36) suggesting very high priority; whereas, the highest Cp value (2.73) of SWS2 and SWS3 (2.52) showed low priority and medium priority, respectively. The prioritization findings identified as a soil erosion-susceptible area can be recommended for adequate control measures for soil erosion and to reduce surface runoff.

Geomorphological monitoring of erosion on restored slopes through the integration of drones, GIS, and LiDAR

Abstract. Mining is a strategic driver of economic development, yet it generates substantial impacts on landscape structure, soil integrity, and water systems. During ecological restoration, slope erosion remains a critical challenge for ensuring long-term geomorphological stability and ecosystem recovery. This study evaluates erosion dynamics on restored mining slopes by integrating Geographic Information Systems (GIS) and Unmanned Aerial Systems (UAS) for high-resolution terrain monitoring and quantification of soil loss. Research was conducted at the Lázaro quarry (Tarragona, Spain) using a fixed-wing UAS equipped with a multispectral camera to produce detailed orthophotos and Digital Elevation Models (DEMs), which were compared with historical LiDAR data. Height Difference Models (HDMs) and volumetric calculations were applied to quantify erosion and deposition. Statistical assessment included descriptive indicators, error metrics (ME, MAE, RMSE), distribution parameters (median, IQR, skewness), and spatial autocorrelation (Moran’s I). Three modelling approaches were developed and compared: a ridge-derived DEM (DEMp), a filtered DEM (DEMf), and a LiDAR-based DEM (DEMl). Their performance was evaluated in terms of accuracy, spatial resolution, and capacity to represent erosional microtopography. Results indicate that DEMp provides the most reliable volume estimates and best preserves pre-erosion morphology. In contrast, DEMf smooths surface detail, whereas DEMl provides an overview representation due to its lower spatial resolution. Overall, the integration of UAS photogrammetry and geospatial analysis proves effective for monitoring restored slopes, supporting precise erosion quantification and improved environmental management toward long-term landscape stability.

Sub-Watershed prioritization for soil and water conservation in the Upper Sebou Watershed (Middle Atlas, northern Morocco) using morphometric compound parameter analysis and GIS

Soil erosion and land degradation pose a persistent threat to semi-arid mountain catchments, where steep relief, erodible substrates, and concentrated seasonal runoff drive high sediment loss. This study prioritizes the 53 sub-watersheds of the Upper Sebou watershed (Middle Atlas, northern Morocco; 7368 km²) for soil and water conser - vation through quantitative morphometric analysis. Basic basin parameters were extracted from a digital elevation model (DEM) in ArcGIS, from which the linear, areal, and relief morphometric parameters were computed using established mathematical formulas. Each parameter was ranked across the sub-watersheds, and the ranks were averaged to obtain a compound parameter (Cp) expressing the relative erosion susceptibility and conservation priority of each unit. Compound parameter values ranged from 19.63 to 38 and were grouped into five priority classes; 12 sub-watersheds (≈23%) were classified as very high and 17 as high priority. The very-high units form a contiguous core along the upper Sebou channel in the center of the basin, together with a detached pocket on the eastern flank, where high drainage density and relief coincide with compact watershed shapes that favor rapid runoff concentration. The drainage network and relief are densest along the central drainage corridor, where the highest-priority sub-watersheds are concentrated; these units also coincide with the more erodible lithologies and the sectors of lowest vegetation cover, which corroborates the ranking with information not used in its calculation. Overall, the approach offers an effective, low-cost means of pinpointing land-degradation hotspots and prioritizing conservation interventions, readily transferable to other data-scarce semi-arid basins.