Dynamic monitoring and spatial evolution analysis of ungoverned Benggang using UAV oblique photogrammetry

This study focuses on unmanaged Benggang landforms in the Jingou small watershed, Jiangxi Province, utilizing UAV oblique photogrammetry for low-altitude remote sensing monitoring in 2017 and 2019 to analyze their spatial evolution patterns. Results indicate ongoing developmental stages of Benggang erosion processes. Key findings include: (1) Total Benggang area increased by 974.12 m² (8.38%) from 2017 to 2019; (2) Most severe erosion occurred in the south-southwest direction, with maximum erosion intensity observed at 180-195 m elevation, showing an annual erosion volume increase of 86.79 m³; (3) Vegetation cover within Benggang areas expanded by 945.58 m² (1.28%) during the study period. The study demonstrates that low-altitude UAV oblique photography provides an efficient methodology for dynamic erosion monitoring, particularly suitable for large-scale Benggang landform assessments. This approach enables high-frequency spatial data acquisition with millimeter-level precision, offering significant advantages over traditional surveying methods in terms of cost-efficiency and temporal resolution.